,transcrib]'s note3 ,text enclos$ by und]scores is 9 italics 7italics74 ,text enclos$ by equal signs is 9 bold face 7bold74 ,?r\gh\t1 an a/]isk 7997 be=e a "n d5otes ext9ct g5]a_/species4 99 99 99 99 99 ,,univ]sity ,,( ,,kansas ,,publications ,,museum ,,( ,,natural ,,hi/ory ,vol4 #af1 ,no4 #f1 pp4 #dgc-egi1 #i figures 9 text ,augu/ #e1 #aifh ,evolution & ,classification ( ! ,pocket ,goph]s ( ! ,subfamily ,geomy9ae ,,by ,,rob]t ,j4 ,,russell ,,univ]sity ,,( ,,kansas ,,lawr5ce #aifh ,,univ]sity ,,( ,,kansas ,,publications1 ,,museum ,,( ,,natural ,,hi/ory ,editors3 ,e4 ,raymond ,hall1 ,*airman1 ,h5ry ,s4 ,fit*1 ,frank ,b4 ,cross1 ,j4 ,knox ,jones1 ,jr4 ,volume #af1 ,no4 #f1 pp4 #dgc-egi1 #i figs4 ,publi%$ ,augu/ #e1 #aifh ,,univ]sity ,,( ,,kansas ,lawr5ce1 ,kansas ,,pr9t$ ,,by ,,rob]t ,r4 7,,bob7 ,,s&]s1 ,,/ate ,,pr9t] ,,topeka1 ,,kansas #aifh ,illu/ration3 ,look = ! ,union label #ca-dfbh ,evolution & ,classification ( ! ,pocket ,goph]s ( ! ,subfamily ,geomy9ae ,,by ,,rob]t ,j4 ,,russell ,,cont5ts ,,page ,,introduction #dgg ,,mat]ials ,,& ,,ackn[l$gm5ts #dgg ,,taxonomic ,,*>act]s #dgh ,prismatic "* ( mol>s #dgh ,"* ( enamel patt]ns #dgi ,groov+ ( incisors #dhj ,masset]ic ridge & fossa #dhj ,basitemporal fossa #dha ,specializations ( skull #dha ,,fossil ,,record #dhd ,mioc5e #dhe ,plioc5e #dhf ,plei/oc5e #dij ,?omomys #dib ,zygogeomys #dif ,geomys #dif ,pappogeomys #ejc ,or?ogeomys #ejd ,,hi/ory ,,( ,,classifications #eje ,,classification #eab ,family ,geomyidae #eab ,subfamily 99,entopty*9ae #eac ,g5us 99,pleurolicus #ead ,g5us 99,gregorymys #ead ,g5us 99,grang]imus #ead ,g5us 99,entopty*us #ead ,subfamily ,geomy9ae #ead ,tribe 99,dikkomy9i #eae ,g5us 99,dikkomys #eaf ,g5us 99,pliosaccomys #eag ,tribe ,?omomy9i #eah ,g5us ,?omomys #eah ,subg5us 99,pleiso?omomys #eai ,subg5us ,?omomys #ebj ,tribe ,geomy9i #eba ,g5us 99,pliogeomys #ebb ,g5us ,zygogeomys #ebc ,g5us ,geomys #ebe ,g5us ,or?ogeomys #ebh ,subg5us ,or?ogeomys #ebi ,subg5us ,het]ogeomys #ecj ,subg5us ,macrogeomys #eca ,g5us ,pappogeomys #ecb ,subg5us ,pappogeomys #ecd ,subg5us ,cratogeomys #ece ,,phylog5y ,,( ,,! ,,geomyidae #ecf ,primitive ,morphotype #ecg ,entopty*id ,radiation #edj ,phyletic ,tr5ds 9 ,subfamily ,geomy9ae #edb ,plio-,plei/oc5e ,radiation ( ,geomy9i #eeh ,morphotype #eei ,specializations 9 ,g5]a #efj ,zygogeomys #efd ,geomys #efe ,or?ogeomys #efh ,pappogeomys #efi ,,lit]ature ,,cit$ #egb ,,introduction ,:5 ,c4 ,h>t ,m]riam wrote 8 monograph ( ! subfamily ,geomy9ae 9 #ahie1 he _h no opportunity to exam9e fossil specim5s4 ,no d\bt 8 phylog5etic conclusions & classification w\ld h be5 greatly influ5c$ _h he enjoy$ t opportunity because /udy ( fossil geomyids reveals ! hi/oric sequ5ce ( phyletic developm5t1 & ?is sequ5ce provides a firm basis = di/+ui%+ specializ$ f primitive *>act]s4 ,! hi/ory ( ! ,geomy9ae has be5 *>act]iz$ by ! evolution ( specializations4 ,^! evolution>y tr5ds beg91 z we pres5tly "k !m1 ) a g5]aliz$ ance/ral /ock 9 ! e>ly ,mioc5e4 ,! direction1 degree1 & rate ( *ange1 beg9n+ ) ! primitive morphotype ( ! subfamily1 has n be5 ! same 9 ! v>i\s l9eages4 ,! classification )9 ! subfamily is bas$ ^u ! phyletic int]pretations ( available data & ! relation%ips !y disclose4 ,9 turn1 a new1 & ,i hope m reali/ic1 phylog5y & classification is (f]$4 ,,mat]ials ,,& ,,ackn[l$gm5ts ,rec5t specim5s 7 /udi$ ( all ! kn[n g5]a1 subg5]a & #bi ( ! #cf liv+ species4 ,mo/ ( ! species n /udi$ are monotypic & h re/rict$ geographic ranges4 ,!y are3 ,geomys colonus1 ,g4 fontanelus1 & ,g4 cumb]l&ius1 ,or?ogeomys cuniculus & ,o4 pygacan?us ( ! subg5us ,or?ogeomys1 & ,o4 d>i5sis & ,o4 matagalpae ( ! subg5us ,macrogeomys4 ,exam9ation ( ^! mod]n species w\ld n radically *ange ! e/imation ( ! degree ( phyletic developm5t ( ! g5]a & subg5]a involv$4 ,all ( ! major polytypic & widespread species 7 /udi$4 ,specim5s ( ! ext9ct g5]a ,dikkomys1 ,pliosaccomys1 ,pliogeomys1 ,n]t]ogeomys1 & ,p>ageomys also 7 /udi$1 z 7 examples ( ! ext9ct species ,geomys qu9ni1 ,geomys tob95sis1 & ,or?ogeomys on]osus4 ,consid]able fossil mat]ial ( liv+ species1 especially ( ! g5]a ,geomys & ,pappogeomys1 0 us$4 ,inasmu* z ! pres5t acc\nt conc]ns ma9ly /ructural *anges 9 ! subfamily ,geomy9ae at ! level ( subg5]a & above1 & ! temporal sequ5ce ( ^? *anges1 no attempt is made 9 ! pres5t acc\nt to revise taxonomy bel[ ! level ( subg5]a4 ,consid]able modification ( ! classification bel[ t level 7= species & subspecies7 is to be expect$ 9 ,or?ogeomys & ,plei/oc5e taxa ( ,geomys :5 available specim5s are /udi$4 ,i ?ank ,pr(4 ,rob]t ,w4 ,wilson = 8 assi/ance 9 secur+ fossil geomyids = /udy1 & ^? 9 *>ge ( ! paleontological collections at ! ,cali=nia ,in/itute ( ,te*nology1 ,pr(4 ,bryan ,patt]son1 =m]ly ( ! ,field ,museum ( ,natural ,hi/ory1 & ,pr(4 ,claude ,w4 ,hibb>d ( ! ,univ]sity ( ,mi*igan1 ,museum ( ,zoology4 ,= _! k9dness 9 l5d+ ,rec5t species1 ,i ?ank ,mr4 ,hob>t ,m4 ,van ,dues5 ( ! ,am]ican ,museum ( ,natural ,hi/ory1 ,dr4 ,david ,h4 ,johnson ( ! ,u4 ,s4 ,national ,museum1 & ,dr4 ,oliv] ,p4 ,pe>son ( ! ,cali=nia ,museum ( ,v]tebrate ,zoology1 ! late ,col9 ,c4 ,sanborn ( ! ,field ,museum ( ,natural ,hi/ory1 & ,pr(s4 ,emmet ,t4 ,hoop] & ,william ,h4 ,burt ( ! ,univ]sity ( ,mi*igan ,museum ( ,zoology4 ,i am especially grateful to ,pr(4 ,e4 ,raymond ,hall = 8 guidance & helpful criticisms ) ! manuscript4 ,= assi/ance ) paleontological problems1 ,i ?ank ,drs4 ,rob]t ,w4 ,wilson & ,william ,a4 ,clem5s4 ,sev]al p]sons h (f]$ helpful sugge/ions & enc\ragem5t 9 ! c\rse ( my /udy4 ,= assi/ance ( v>i\s sorts ,i especially ?ank ,drs4 ,j4 ,knox ,jones1 ,jr41 ,roll9 ,h4 ,bak]1 ,a4 ,byron ,leon>d1 ,sydney ,&]son1 ,james ,s4 ,f9dley1 ,rob]t ,l4 ,pack>d1 & ,rob]t ,g4 ,&]son4 ,advice conc]n+ ! draw+s ( ! d5titions 0 g5]\sly giv5 by ,mr4 ,victor ,hogg1 & ! draw+s 7 done by ,mrs4 ,lorna ,cordonni] "u 8 direction & by ,mr4 ,?omas ,h4 ,swe>+54 ,= assi/ance ) secret>ial tasks ,i ?ank ,val]ie ,/all+s1 ,violet ,g\rd1 ,ann ,ma*91 ,toni ,w>d1 ,%eila ,mill]1 & my wife1 ,danna ,russell4 ,,taxonomic ,,*>act]s ,morphological features ( ! fossils & _! /ratigraphic prov5i5ce provide ! in=mation ^u :i* phylog5etic int]pretations are bas$4 ,al?\gh ! mo/ critical sequ5ces ( ! fossil record are lack+1 & al?\gh ! exi/+ fossils are mo/ly fragm5t>y & !re=e seldom furni% ideally suitable data = ! int]pretations t h be5 made1 phylog5etic conclusions drawn f fossil mat]ials are sup]ior to ^? drawn on o!r bases4 ,! especially relevant *>act]s are ^? disclos+ prim>y tr5ds 9 ! evolution ( ! mod]n assemblages4 ,! high] sy/ematic categories recogniz$ 9 ! foll[+ acc\nt are bas$ prim>ily ^u su* *>act]s4 ,! mo/ important *>act]s f\nd are 9 ! tee?1 al?\gh sev]al /ructural *anges 9 ! l[] jaw1 especially ^? associat$ ) ! ins]tion ( cranial musculature1 are almo/ z important4 ,prismatic ,"* ( ,mol>s ,9 primitive geomy9es ! mol> consi/$ ( two columns unit$ at _! mid-po9ts & =m+ a figure #h or ,h-patt]n 7see ,fig4 #d;,b74 ,bo? labial & l+ual re-entrant folds 7 =m$ betwe5 ! two columns4 ,! primitive patt]n is reta9$ 9 ! premol>s ( all kn[n ,geomy9ae4 ,!re=e1 9 ! e>lie/ 7,mioc5e7 memb]s ( ! subfamily1 ! patt]n ( ! mol>s 0 ess5tially l t ( ! premol>s4 ,9 ,plioc5e ,geomy9ae ! two columns ( ! mol>s t5d to m]ge into "o4 ,?is is evid5t on ! worn occlusal surface ( ! tee?2 ! lat]al re-entrant folds are %all[ v]tically & progressively rec$e lat]ally until only a slight inflection rema9s4 ,9 ! f9al /ages ( attrition1 ! inflection disappe>s & ! too? is a simple elliptical column4 ,9 ! ,plei/oc5e ! monoprismatic patt]n appe>s at e>li] /ages ( we> ow+ to ! decrease 9 dep? ( ! re-entrant folds1 & 9 ,geomy9ae ( ,rec5t "t ! initial /ages ( we> on ! enamel cap ( infants erase ! la/ ve/iges ( two columns 9 ! mol> tee?4 ,! g5]al tr5d 9 evolution1 !re=e1 has be5 f a bicolumn> to a monocolumn> patt]n4 ,! p>ticul> patt]ns ( we> *>act]iz+ ea* g5us are describ$ 9 detail beyond4 ,! ?ird upp] mol> has evolv$ less rapidly ?an ! fir/ & second & 9 "o ( ! mod]n l9eages 7tribe ,geomy9i7 t5ds to reta9 at lea/ a ve/ige ( ! primitive bicolumn> patt]n 9 ! f9al /age ( we>4 ,!re=e1 ! loss ( any trace ( ! bicolumn> patt]n 9 ,m#c is consid]$ to be a mu* specializ$ condition4 ,un=tunately1 ! fossil record ( ! ?ird upp] mol> is less complete ?an t = ! fir/ mol> & second mol>2 ! too? drops out ( its alveolus m (t5 ?an does any "o ( ! o!r mol>i=m tee? & is seldom recov]$4 ,"* ( ,enamel ,patt]ns ,9 ! primitive g5]a ! enamel patt]n is bilophate & ! enamel loop 7see ,fig4 #d;,b7 is cont9u\s on ! occlusal surface ( a worn mol>4 ,concomitant ) ! union ( ! d\ble columns1 ! bilophodont patt]n is r$uc$ to a s+le loph1 b ! enamel /ill completely encircles ! d5t9e4 ,9 ! mol>s ( mod]n geomy9es1 ! enamel loop is n cont9u\s b is int]rupt$ on ! sides ( ! cr[n by v]tical tracts ( d5t9e t are expos$ at ! occlusal surface ( ! too? dur+ e>ly /ages ( we>4 ,!re=e1 a cont9u\s enamel b& is to be f\nd only 9 a juv5al individual ^: tee? h be5 subject$ to only slight attrition on ! enamel cap4 ,9 mol>s lack+ enamel on ! labial & l+ual sides1 ant]ior & po/]ior enamel plates1 or blades1 are f\nd on ea* mol>4 ,! premol> also has an enamel plate on ! ant]ior surface & ano!r on ! po/]ior surface1 & 9 addition bo? re-entrant angles are protect$ by a ,v-%ap$ inve/m5t ( enamel4 ,"o or ! o!r ( ! v>i\s plates c be r$uc$ or lo/ acc\nt+ = ! sev]al di/9ctive too?-patt]ns ( ! mod]n geomy9es4 ,if loss occurs1 x usually is ! ant]ior plate 9 ! l[] d5tition & ! po/]ior plate 9 ! upp] d5tition1 includ+ ! upp] premol>4 ,:5 r$uction ( ! po/]ior plate ( ! upp] *eek tee? occurs1 enamel is fir/ lo/ f ! labial side ( ! too?1 ?us leav+ only a %ort ve/igial plate on ! l+ual end ( ! cr[n4 ,groov+ ( ,incisors ,! incisors are smoo? ) no trace ( a groove 9 ! ance/ral l9eage4 ,9 ! specializ$ assemblage 7tribe ,geomy9i7 pron\nc$ grooves are always develop$ on ! ant]ior face ( ! upp] incisor4 ,! patt]n ( groov+ is con/ant 9 ea* species & ?us provides *>act]s ( taxonomic wor? = gr\p+ species into g5]a4 ,! only incon/ancy not$ 0 an incisor ( ,geomys f ! ,tob9 local fauna ( ! middle ,plei/oc5e :i* has ?ree grooves r ?an ! normal two 7,no4 #fgah ,,ku74 ,! extra groove is an obvi\s abnormality1 & ! too? 0 associat$ ) o!rs ( ! same species f ! same qu>ry t 7 normally groov$4 ,grooves on ! l[] incisors are unkn[n4 ,! functional significance ( groov+ has be5 debat$ on num]\s occasions 9 ! lit]ature4 ,grooves appe> 9 a numb] ( only di/antly relat$ rod5ts & 9 lagomorphs4 ,! groov+ occurs always 9 small h]bivor\s mammals1 & 9 "s way may be relat$ to fe$+ habits4 ,! grooves provide a s]rat$ cutt+ edge on ! occlusal edge ( ! upp] incisor4 ,9 ! g5us ,geomys1 = example1 ! two incisors1 includ+ ! slight space betwe5 !m1 pres5t a total ( five s]rations1 :i* may facilitate cutt+ & pi]c+ tub]\s & fibr\s roots ^u :i* ,geomys fe$s4 ,also ! sulci w\ld p]=m ! same function z ! longitud9al groove on ! side ( a bayonet1 & w\ld aid ! animal 9 extract+ its upp] incisors f co>se1 fibr\s mat]ial4 ,9 ga!r+ food1 ! goph] s9ks its upp] incisors into a root1 & !n1 ) ! upp] incisors firmly an*or$1 slices (f small *unks by means ( ! l[] incisors4 ,!re=e1 9 pocket goph]s1 groov+ may be an adaptation = fe$+ on fibr\s or woody mat]ial4 ,f9ally1 grooves increase ! enamel surface ( ! incisor )\t additional broad5+ ( ! too? itself4 ,!re c\ld be a selective advantage = sulcation if ! extra enamel & ! s]rate patt]n /r5g!n ! incisors1 :i* are "u heavy /ress :ile p5etrat+ or pry+ (f pieces ( co>se mat]ial4 ,few brok5 incisors ( pocket goph]s are f\nd4 ,masset]ic ,ridge & ,fossa ,?is ridge & fossa are on ! lat]al surface ( ! ramus4 ,! cre/ on ! ridge beg9s at ! base ( ! angul> process & t]m9ates slightly ant]ior to ! plane ( ! l[] premol>4 ,! masset]ic fossa receives ! ins]tion ( ! ro/ral or sup]ficial division ( ! masset] muscle4 ,! m5tal =am5 lies imm$iately ant]ior1 or ant]ov5tral1 to ! fossa4 ,9 ! ance/ral l9eage1 ! ridge is di/9ct b relatively l[2 ! masset]ic fossa is %all[ & is a poorly develop$ area = atta*m5t ( ! sup]ficial masset] muscle4 ,9 mod]n ,geomy9ae ! ridge is massive & =ms a high cre/1 especially ant]iorly1 & ! masset]ic fossa is a deep1 prom95t cup along ! dorsal side ( ! cre/4 ,! elaboration ( ! cre/ & fossa evid5tly is associat$ ) an increase 9 size ( ! sup]ficial masset] muscle1 :i* enl>ges & provides increas$ p[] = ! propal9al type ( ma/ication4 ,a high cre/ has evolv$ indep5d5tly 9 bo? mod]n l9eages1 ,?omomy9i & ,geomy9i4 ,basitemporal ,fossa ,! "n basitemporal fossa is sugge/$ "h to d5ote ! deep pit t lies betwe5 ! l+ual base ( ! coronoid process & ! ?ird l[] mol>4 ,! basitemporal fossa receives ! ins]tion ( ! temporal muscle4 ,! fossa1 :i* until n[ has n be5 nam$1 is a unique feature 9 advanc$ ,geomy9ae1 be+ unkn[n 9 ei!r primitive ,geomy9ae or 9 o!r rod5ts4 ,! temporal is "o ( sev]al muscles hold+ ! occlusal surface ( ! l[] mol>i=m d5tition firmly aga9/ ! upp] *eek tee? dur+ ma/ication4 ,9 primitive geomy9es t ma/icate food by a plan+ action1 ! temporal muscle also moves ! m&ible po/]iorly & food is gr\nd betwe5 ! enamel plates :5 ! l[] jaw is retract$ z well z :5 x is mov$ =w>d4 ,! basitemporal fossa appe>s 9 late ,plioc5e geomy9es & increases ! atta*m5t surface ( ! temporal muscles t p[]s ! plan+ action important 9 utiliz+ woody & fibr\s foods4 ,! basitemporal fossa develop$ 9 only "o ( ! mod]n l9eages 7tribe ,geomy9i71 ! same l9eage 9 :i* groov$ incisors evolv$4 ,bo? features probably are adaptations = fe$+ on co>se food4 ,! fossa is n greatly develop$ 9 ei!r ! ance/ral tribe ,dikkomy9i or ! mod]n tribe ,?omomy9i1 al?\gh 9 "s specim5s a slight depression m>ks ! site ( ! basitemporal fossa4 ,illu/ration3 ,,fig4 #a4 ,types ( skulls 9 ! subfamily ,geomy9ae4 #a4 ,a4 & ,b4 ,g5]aliz$ type ( skull4 ,geomys burs>ius lutesc5s1 adult1 male1 ,no4 #ggiee ,,ku1 #aj mi4 ,n ,spr+view1 ,keya ,paha ,co41 ,nebraska4 ,a4 ,dorsal view ( skull4 ,b4 ,v5tral view ( l[] jaw4 ,c4 & ,d4 ,doli*ocephalic type ( skull4 ,or?ogeomys 7,or?ogeomys7 gr&is gu]r]5sis1 adult1 female1 ,no4 #cihjg ,,ku1 #a_/b mi4 ,e ,la ,mira1 #cjj ft41 ,mi*oacn1 ,mxico4 ,c4 ,dorsal view ( skull4 ,d4 ,v5tral view ( l[] jaw4 ,e4 & ,f4 ,platycephalic type ( skull4 ,pappogeomys 7,cratogeomys7 gymnurus tellus1 adult1 female1 ,no4 #ccded ,,ku1 #c mi4 ,w ,tala1 #dcjj ft41 ,jalisco1 ,mxico4 ,e4 ,dorsal view ( skull4 ,f4 ,v5tral view ( l[] jaw4 ,specializations ( ,skull ,! skull 9 mo/ geomy9es is g5]aliz$1 be+ nei!r extremely long & n>r[ nor %ort1 broad & flat z 9 specializ$ skulls 7see ,fig4 #a74 ,9 ,plei/oc5e l9eages ( ! mod]n tribe ,geomy9i1 long skulls & broad skulls evolv$ & h be5 t]m$ doli*ocephalic & platycephalic specializations1 respectively by ,m]riam 7#ahie3hh-aja74 ,he correlat$ !m ) two diametrically diff]5t me*anical me?ods ( ma/ication4 ,9 animals ) doli*ocephalic skulls ! pr9cipal movem5ts ( ! m&ible 9 ! ma/icatory process are ant]opo/]ior4 ,! result+ propal9al action ( enamel plates 9 opposition to ea* o!r *>act]izes also animals ) a g5]aliz$ skull1 & evid5tly is ! me?od ( ma/ication 9 ! primitive geomy9es1 b 9 animals ) a doli*ocephalic skull ! me?od is develop$ to a high degree by elongation ( ! cranium1 m&ible1 & tee?4 ,bo? ! m&ibul> & maxill>y too?-r[s are relatively long] ?an 9 ! g5]aliz$ skull1 provid+ a long] block = ! plan+ action ( ! l[] mol>i=m tee?4 ,all tee?1 especially ,p#d & ,m#c1 are long]4 ,9 ,m#c ! heel 7po/]ior loph7 9 p>ticul> is elongat$4 ,bo? ! ant]ior & po/]ior enamel plates usually are reta9$ 9 ,m#a & ,m#b4 ,! sup]ficial 7or ro/ral7 masset] muscle1 orig9ates on ! side ( ! ro/rum & ins]ts 9 ! masset]ic fossa & on ! masset]ic ridge4 ,! deep masset]1 especially ! zygomatic "p hav+ its orig9 along ! zygomatic ar*1 ins]ts on ! angul> process ( ! l[] jaw4 ,^! two divisions ( ! masset] muscle h a long] pull 7=w>d7 9 ! doli*ocephalic skull ?an 9 a non-doli*ocephalic skull4 ,! temporal & diaga/ric muscles retract ! l[] jaws4 ,o!r1 second>y1 modifications ( ! doli*ocephalic skull are %ort5+ ( ! angul> process ( ! m&ible1 broad5+ ( ! ro/rum1 & n>r[+ ( ! cranium & zygomata4 ,dep? ( ! po/]ior "p ( ! skull is un*ang$4 ,! skull appe>s to be deep & ( ne>ly equal bread? f nasals to occiput4 ,a good example ( a doli*ocephalic skull is t ( ,or?ogeomys 7see ,fig4 #a1 ,c & ,d74 ,9 ! platycephalic skull1 ! pr9cipal ma/icatory movem5t ( ! m&ible is ant]ooblique1 to "o side & !n to ! o!r4 ,! oblique passage ( ! enamel blades ( ! l[] tee? across ^? ( ! upp] tee? produces a %e>+ r ?an plan+ action 7,fig4 #a;,e1 ,f74 ,! ant]ooblique movem5t ( ! l[] jaw is possible because ( major ar*itectural *anges 9 ! cranium & m&ible4 ,^! *anges include3 7#a7 ,broad5+ ( ! po/ro/ral "p ( ! skull1 especially ! occiput 7ma/oidal bread? equals or exce$s zygomatic bread? 9 skulls ( "s taxa72 7#b7 flatt5+ ( ! skull2 7#c7 ant]opo/]ior compression ( ! mol>i=m tee?1 especially ! mol>s4 ,!re=e1 ! entire maxill>y too?-r[ is relatively %ort] ?an 9 ! doli*ocephalic skull4 ,only a ve/ige ( ! heel ord9>ily rema9s on ,m#c4 ,! loss ( ! po/]ior enamel blades ( ,p#d1 ,m#a1 & ,m#b elim9ates unnecess>y friction1 & ea* ( ^! tee? is wid] ?an long4 ,! di/ance betwe5 ! po/]ior ends ( ! l[] jaws is increas$ approximately 9 proportion to ! ext5t t ! occiput is wid5$4 ,z a result ( ! flatt5+ ( ! skull ! angul> processes ( ! l[] jaws are lat]al to ! zygomatic ar*es1 & approximately on ! same v]tical level ) !m4 ,consequ5tly ! ins]tions ( ma/icatory muscles are %ift$ lat]ally4 ,?is is especially true ( ! zygomatic division ( ! deep masset]1 :i* ins]ts on ! angul> process4 ,contraction ( t muscle division ( "o side ( ! skull moves ! l[] jaws obliquely =w>d4 ,! diaga/ric & temporal muscles ( c\rse retract ! l[] jaws4 ,! platycephalic skull is ! mo/ specializ$ skull 9 ! ,geomy9ae & is a result ( ! new 7= ! ,geomy9ae7 me?od ( ma/ication4 ,! subg5us ,cratogeomys 7see ,fig4 #a1 ,e & ,f7 has a platycephalic skull4 ,! tr5d t[>d platycephalic specialization has be5 ! major feature ( evolution 9 ,cratogeomys4 ,,fossil ,,record ,! fossil record ( ! subfamily ,geomy9ae beg9s 9 ! e>ly ,mioc5e ( we/]n ,nor? ,am]ica4 ,no geomyids h be5 recov]$ f b$s ( ! late ,mioc5e age4 ,beg9n+ ) ! e>ly ,plioc5e ! fossil record becomes progressively m complete1 & geomy9es are relatively abundant 9 deposits ( late ,plioc5e & ,plei/oc5e age4 ,al?\gh pocket goph]s ( ! subfamily ,geomy9ae are r>e 9 l[] ,mioc5e deposits1 memb]s ( ! subfamily ,entopty*9ae are relatively common & highly div]sifi$4 ,f\r g5]a & a numb] ( species h be5 describ$ 7see ,wood1 #aicf3d-be71 & ! subfamily rang$ widely 9 we/]n ,nor? ,am]ica4 ,i int]pret ?is to mean t ! geomy9es 7 inde$ uncommon 9 ! e>ly ,mioc5e & _! di/ribution re/rict$ s9ce s few ( _! rema9s h be5 recov]$ 9 comp>ison ) entopty*9es & ! kn[n records are only f ! nor!rn "p ( ! ,great ,pla9s4 ,on ! o!r h&1 entopty*9es enjoy$ a widespread di/ribution 9 we/]n ,nor? ,am]ica 7see discussion beyond74 ,probably ! geographic range ( ! geomy9es 0 l>gely allopatric to t ( ! m specializ$ entopty*9es4 ,! zone ( fossoral adaptation = h]bivor\s rod5ts is ecologically n>r[1 & z a result competition is sev]e4 ,z a rule1 ! outcome ( episodes ( int]gr\p competition is geographic exclusion4 ,if ^! rod5ts 7 fossorial 9 ! e>ly ,mioc5e--_! morphology sugge/s !y 7 at lea/ semi-fossorial--mutually exclusive patt]ns ( di/ribution are to be expect$4 ,mioc5e ,dikkomys is ! only g5us ( ! ,geomy9ae kn[n f ! e>ly & middle ,mioc5e4 ,dikkomys mat!wi 0 describ$ by ,wood 7#aicf7 on ! basis ( isolat$ tee? f l[] ,h>rison deposits 7,arik>eean 9 age7 ne> ,agate1 ,si\x ,c\nty1 ,nebraska4 ,lat]1 ,galbrea? 7#aidh3caf-cag7 describ$ ! features ( an almo/ complete m&ible recov]$ f ! y\ng] upp] ,rosebud deposits1 n[ consid]$ by ,mac,donald 7#aifc3adi-aej7 to be middle ,mioc5e1 ne> ,w\nd$ ,knee1 ,%annon ,c\nty1 ,s\? ,dakota4 ,m rec5tly ,black 7#aifa3ac7 has describ$ a new species1 ,dikkomys woodi1 f ! ,deep ,riv] ,=mation1 ,meagh] ,c\nty1 ,montana4 ,! ,deep ,riv] ,=mation is late ,hem+=dian 7middle ,mioc5e7 9 age4 ,no rema9s ( ,dikkomys h be5 id5tifi$ 9 ! ext5sive rod5t fauna ( ! ,john ,day b$s ( ! l[] ,mioc5e ( ,oregon1 al?\gh entopty*9es are abundant 9 ^! deposits4 ,9 ! pres5t acc\nt1 ,dikkomys is reg>d$ z ! ance/or f :i* ! ,plioc5e & mod]n geomy9es 7 d]iv$4 ,^! probably did n evolve f ! subfamily ,entopty*9ae because ! d5tition ( entopty*9es1 especially ! premol>s & ?ird mol>s1 0 already highly specializ$ by ,mioc5e "t4 ,! num]\s records ( ,?omomys & especially ,geomys report$ f suppos$ ,mioc5e or ,plioc5e deposits are )\t f\ndation 7see ,mat!w1 #ahii3ff2 #aiji3aad1 #aaf1 #aai2 #aiaj3fg1 #gb2 #aibc;a3#cfi2 #aibd3ff2 ,mat!w & ,cook1 #aiji3chb2 ,cook & ,cook1 #aicc3di2 & ,simpson1 #aide3hj74 ,mo/ ( ! records ( ,geomys date back to ! description ( ,geomys bisculcatus ,m>% 7#ahga3aba7 f ! ,l\p ,=k b$s ( ,nebraska 7ne> ,camp ,?omas on ! ,middle ,l\p ,riv]74 ,at fir/ ,m>% & o!r inve/igators ?\ght ^! b$s 7 ( ! late ,mioc5e age4 ,subsequ5tly ! ,l\p ,=k fauna 0 det]m9$ by ,mat!w 7#aibc;b7 to be mo/ly e>ly ,plioc5e 7,cl>5donian71 b ) a lat] ,plei/oc5e elem5t4 ,rec5tly1 ,s*ultz & ,/\t 7#aidh3efj7 h %[n t ! v>i\s ,l\p ,riv] faunas & also ^? f along ! ,niobr>a ,riv] 7,hay ,spr+s1 ,ru%ville1 ,gordon local faunas7 are ( middle ,plei/oc5e age1 ! fossil-be>+ b$s occurr+ j bel[ ! ,pe>lette ,a%4 ,^! b$s are ^? t]m$ ! ,l\p ,=k or ,nor? ,prong ( ,middle ,l\p by ! e>li] work]s :o suppos$ !m to be ( ,mioc5e or ,plioc5e age4 ,bo? ,geomys & ,?omomys h be5 recov]$ f mo/ ( ^! deposits1 b !y are no old] ?an middle ,plei/oc5e4 ,?is is n surpris+ 9 view ( ! primitive /ructure ( ! geomyids kn[n f ,mioc5e & ,plioc5e b$s1 b ! suppos$ e>ly appe>ance ( ,geomys & ,?omomys l$ to mu* confusion conc]n+ geomyid evolution 9 ! late ,t]ti>y4 ,! de>? ( geomy9es 9 ! ,mioc5e is c\nt]balanc$ by ! relatively abundant & highly diff]5tiat$ goph]s ( ! subfamily ,entopty*9ae4 ,!y rea*$ ! z5i? ( _! developm5t 9 ?is p]iod4 ,f\r g5]a & a numb] ( species are kn[n f ! we/]n "p ( ! ,unit$ ,/ates1 mo/ly f b$s along ! ,pacific ,coa/ & 9 ! nor!rn "p ( ! ,great ,pla9s4 ,! great div]sification ( ! gr\p 9 a relatively %ort p]iod sugge/s prior movem5t into a new adaptive zone & subsequ5t specialization 9 diff]5t subzones & !re=e an episode ( radial adaptation4 ,! radiation ( ! entopty*9es is discuss$ else:]e 9 ! acc\nt ( geomyid phylog5y1 b x %\ld be not$ "h t bo? ! ,geomy9ae & ! ,entopty*9ae appe> 9 ! fossil record at ab\t ! same "t 9 ! e>ly ,mioc5e4 ,! pr9cipal di/+ui%+ features ( ea* ( ! two l9eages 7 well develop$ at ! "t ( _! fir/ occurr5ce1 & ! entopty*9es 7 ! m successful 9 e>ly ,mioc5e4 ,! ,entopty*9ae are kn[n only f ! e>ly & middle ,mioc5e1 unless ! e>li] deposits ( ! ,john ,day ,=mation ( ,oregon f :i* mammals h be5 recov]$ are consid]$ to be late/ ,:itneyian 7late/ ,oligoc5e72 = correlations1 see ,wilson 7#aidi3ge74 ,bo? l9eages likely _h an e>li] hi/ory ext5d+ back to _! div]g5ce 9 ! ,oligoc5e4 ,plioc5e ,! olde/ & mo/ primitive ,plioc5e geomy9e is ,pliosaccomys dubius ,wilson 7#aicf3bj7 f ! ,smi? ,valley local fauna ( middle ,plioc5e 7,hemphillian7 age 9 ,nevada4 ,accord+ to ,wilson 7op4 cit43#ae7 ! b$s probably 7 deposit$ ne> ! middle ( ,hemphillian "t4 ,%otwell 7#aief3gcj7 record$ ,pliosaccomys dubius f ! ,mc,kay ,res]voir & f ! ,otis ,bas9 7#aifc3gc7 local faunas ( ! middle ,plioc5e 7,hemphillian7 ( ,oregon1 & ,gre5 7#aief3aee7 has recov]$ rema9s ( ,pliosaccomys 7cf4 dubius7 f ! ,wolf ,creek local fauna1 upp]mo/ "p ( ! l[] ,plioc5e 7late ,cl>5donian 9 age71 ( ,%annon ,c\nty1 ,s\? ,dakota4 ,rec5tly1 ,james 7#aifc3aja7 has describ$ a second species1 ,pliosaccomys wilsoni1 ( ?is primitive g5us4 ,! new species 0 f\nd 9 e>ly ,plioc5e deposits 7late ,cl>5donian7 f ! ,nettle ,spr+ local fauna 7,apa*e ,canyon71 9 ! ,cuyama ,valley1 ,v5tura ,c\nty1 ,cali=nia4 ,pliosaccomys wilsoni does n diff] greatly f ,p4 dubius2 h[ev]1 ! few diff]5ces 9 d5tal *>act]s seem to w>rant specific recognition4 ,! r$uction ( cusps on ! metalophid ( p#d f ?ree 7dubius7 to two 7wilsoni7 & ! lack ( accessory cuspules on ! protolophid ( p#d 9 wilsoni are probably specializations1 sugge/+ t ,p4 dubius ev5 ?\gh ! m rec5t 9 age is ! less advanc$ ( ! two4 ,p4 wilsoni is kn[n only f a l[] jaw ( a "y individual t _h dp#d 9 place1 along ) m#a & m#b4 ,! p]man5t premol> 0 9 ! process ( erupt+1 & ! decidu\s too? 0 remov$ s t ! unworn surface ( p#d c\ld be exam9$4 ,pliosaccomys occurr$ geographically 9 ! area t ! ,entopty*9ae _h occupi$ 9 ! e>ly ,mioc5e4 ,! ,smi? ,valley mat]ial includes d5titions 9 almo/ all /ages ( we> & ! *ronological sequ5ces 9 ! developm5t ( ! patt]ns ( we> c be recon/ruct$4 ,an und]/&+ ( ! d5tal patt]ns ( ! primitive geomy9es is bas$ mo/ly on ! int]pretation ( ! /ages ( we> 9 ,pliosaccomys4 ,no o!r pocket goph] is kn[n f ! area 9 :i* ,pliosaccomys occurr$1 & x is unkn[n aft] middle ,hemphillian age4 ,pliosaccomys has clos] aff9ities ) ,dikkomys ( ! e>ly ,mioc5e ?an ) any geomyid ( ! mod]n assemblage & gives no clue to ! orig9 ( ! l9eage culm9at+ 9 ! mod]n pocket goph]s ( ! tribe ,geomy9i4 ,pliogeomys buisi ,hibb>d 7#aied3cec7 0 f\nd 9 ! ,buis ,ran* local fauna1 ( late/ middle ,plioc5e1 on ! we/ side ( ,buck%ot ,arroyo1 ,beav] ,c\nty1 ,oklahoma4 ,! orig9al mat]ial includ$ a "r ramus be>+ ! premol> & fir/ two mol>s 7! holotype7 & five isolat$ premol>s & mol>s4 ,"o ( ! mol>s is slightly worn & f an immature individual4 ,"o premol> is a decidu\s too?4 ,hibb>d 7op4 cit43#cdb7 id5tifi$ ! b$s f :i* he obta9$ ! ,buis ,ran* local fauna z f ! l[]mo/ "p ( ! ,upp] ,plioc5e4 ,moreov]1 he judg$ ! ,buis ,ran* local fauna to be only slightly old] ?an ! ,saw ,rock ,canyon local fauna ( ,sew>d ,c\nty 9 s\?we/]n ,kansas4 ,previ\sly 7,hibb>d1 #aiec3djh-daj71 ! ,saw ,rock ,canyon local fauna _h be5 assess$ z old] ?an ! ,rexroad local faunas 7late/ late ,plioc5e7 &1 !re=e1 repres5tative ( ! e>ly "p ( ! late ,plioc5e4 ,m rec5tly1 ,hibb>d 7#aief3afd7 id5tifi$ ! ,buis ,ran* b$s z "p ( ! ,ogallala ,=mation1 :i* "h occurs uncon=mably j b5ea? ! ,rexroad ,=mation 7compos$ ( /rata ne>ly all ( late ,plioc5e age74 ,!re=e1 he reg>d$ ! ,buis ,ran* b$s z late/ middle ,plioc5e 9 age4 ,hibb>d 7#aied3cef7 sugge/$ t pocket goph] rema9s f ! ,saw ,rock ,canyon local fauna 7 ref]able to ,pliogeomys buisi1 &1 9 effect1 t5tatively assign$ !m to ,pliogeomys 79 8 description ( ! g5us ,hibb>d rem>k$ t ! upp] incisor is bisulcate z 9 ,geomys1 & ! only upp] incisor t he m5tions 0 "o ( ! ,saw ,rock ,canyon fossils & n "p ( ! ,buis ,ran* mat]ial74 ,pliogeomys has clos] aff9ities ) mod]n pocket goph]s ( ! tribe ,geomy9i ?an x does ) ! middle ,plioc5e g5us ,pliosaccomys4 ,! pocket goph] fauna kn[n f ! late ,plioc5e 0 m v>i$ ?an ! faunas kn[n f any e>li] "t4 ,9 addition to ! ext9ct ,pliogeomys1 :i* occurs 9 e>ly late ,plioc5e 7see discussion above71 ! liv+ g5]a ,zygogeomys1 ,geomys1 ,pappogeomys 79 ! s5se us$ on p4 #ecd71 & ,?omomys fir/ appe> 9 ! late ,plioc5e4 ,! only o!r liv+ g5us1 ,or?ogeomys1 makes its fir/ appe>ance 9 ! late ,plei/oc5e4 ,! e>lie/ record ( ! g5us ,?omomys is bas$ on a fragm5t ( a left m&ibul> ramus be>+ p#d & m#a1 ,?omomys gidleyi ,wilson 7#aicc;b3#abb71 f ! ,hag]man local fauna ( ,tw9 ,falls ,c\nty1 ,idaho4 ,wilson 7loc4 cit47 0 unc]ta9 z to age 7late ,plioc5e or e>ly ,plei/oc5e7 b subsequ5tly 7#aicg3ch & #fg-gj7 settl$ on ! middle "p ( ! late ,plioc5e4 ,hibb>d 7#aieh3aa7 lat] consid]$ ! age z e>ly ,plei/oc5e 7sugge/+ t ! deposits accumulat$ 9 ! ,aftonian int]glacial int]val7 b subsequ5tly 7,hibb>d et al41 #aife3eab71 on ! basis ( potassium argon age det]m9ations1 also settl$ on late ,plioc5e4 ,rema9s ( ,n]t]ogeomys ,zygogeomys h be5 f\nd 9 ! ,b5son local fauna1 ,co*ise ,c\nty1 ,arizona1 & ! ,rexroad local fauna ( ,kansas4 ,?is e>ly ,blancan goph] fir/ 0 describ$ z ,geomys m9or by ,gidley 7#aibb3abc71 & 0 lat] ref]r$ by ,gaz9 7#aidb3dhg7 to 8 new g5us ,n]t]ogeomys4 ,hibb>d 7#aiej3ach7 id5tifi$ specim5s f ! ,fox ,canyon locality1 "o ( ! localities ( ,meade ,c\nty1 ,kansas1 :]e ! ,rexroad local fauna is pres]v$1 z ,n]t]ogeomys1 & t5tatively ref]r$ !m to ! species ,n4 m9or4 ,n]t]ogeomys cf4 m9or has be5 recov]$ also f ,locality #c ( ! ,rexroad local fauna 7,hibb>d1 #aiej3aga7 ( ,meade ,c\nty1 ,kansas4 ,app>5tly ^! are also ! small goph]s ab\t :i* ,franz5 7#aidg3eh7 wrote4 ,%e assign$ !m to ! g5us ,geomys1 & !y may actually be a primitive =m ( ,geomys t repres5ts an int]m$iate /age 9 ! developm5t ( ! enamel patt]n f ! un9t]rupt$ loops ( ! ance/or to ! discont9u\s patt]n ( mod]n ,geomys4 ,i favor ?is int]pretation2 ! evid5ce1 h[ev]1 is inconclusive1 & ,i h1 !re=e1 reluctantly allocat$ !m1 along ) ! o!r specim5s ( ,n]t]ogeomys1 to ! g5us ,zygogeomys4 ,9 an e>ly pap]1 ,hibb>d 7#aich3bdd7 errone\sly ref]r$ ! same specim5s1 two upp] premol>s ( a "y individual1 to ! g5us ,?omomys1 & ! same mat]ial 0 id5tifi$ ) ! g5us ,geomys1 also )\t specific assignm5t1 9 a lat] pap] 7,hibb>d1 #aida;b3#bgh74 ,?omomys is unkn[n f ! late ,plioc5e ( ! ,great ,pla9s4 ,! specim5s previ\sly ref]r$ to ,n]t]ogeomys are assign$ to ! g5us ,zygogeomys = ! fir/ "t 9 ?is report2 = a discussion ( ! sy/ematic arrangem5t see ! acc\nts beyond4 ,! type & p>atype ( ,n]t]ogeomys f ! ,b5son local fauna ( ,arizona h no indication ( enamel r$uction4 ,specim5s ( ! g5us ,geomys f ! late ,plioc5e 7 ref]r$ to ! l>ge ,geomys qu9ni ,mc,grew1 fir/ by ,franz5 7#aidg3ee7 & lat] by ,hibb>d & ,riggs 7#aidi3hce7 & ,hibb>d 7#aiej3aga74 ,geomys qu9ni has be5 obta9$ f ! ,fox ,canyon locality & ,locality #c ( ! ,rexroad local fauna4 ,at ,locality #c1 bo? ,zygogeomys 7cf4 m9or7 & ,geomys qu9ni h be5 f\nd toge!r1 b ,geomys qu9ni c be di/+ui%$ by its mu* l>g] size & ! advanc$ enamel patt]n ( ! *eek tee? 7see sy/ematic acc\nts beyond74 ,all age classes are repres5t$ among ! specim5s ( ,geomys qu9ni2 !re=e1 x seems unlikely t ! small] goph]s ref]r$ to ,zygogeomys are actually ! "y ( ,geomys qu9ni4 ,hibb>d 7p]sonal communication1 ,may1 #aiff7 in=m$ me t specim5s ( ,geomys f ! late ,plioc5e 7,fox ,canyon & ,rexroad ,locality #c7 are errone\sly ref]r$ to ,g4 qu9ni4 ,accord+ to ,hibb>d1 ?is mat]ial repres5ts in/ead two di/9ct undescrib$ species1 descriptions ( :i* h be5 submitt$ by him = publication4 ,allocation ( late ,plioc5e specim5s ( ,geomys qu9ni to o!r species w re/rict qu9ni to ! e>ly ,plei/oc5e4 ,cratogeomys b5soni ,gidley 7#aibb3abc7 0 ( m$ium size4 ,! "n 0 bas$ on an upp] incisor be>+ a s+le m$ian sulcus & an associat$ l[] jaw conta9+ all ( ! *eek tee? f ! ,b5son local fauna1 ,co*ise ,c\nty1 ,arizona4 ,additional l[] jaws c>ry+ v>i\s tee? also 7 recov]$4 ,! specim5s might j z well h be5 assign$ to ! g5us ,pappogeomys s9ce ! l[] d5titions ( all ! g5]a ( ! tribe ,geomy9i h ! same enamel patt]n1 & ! subg5]a ,pappogeomys & ,cratogeomys h upp] incisors ) m$ian grooves4 ,! specim5s are too fragm5t>y to w>rant m ?an g5]ic id5tification4 ,ma9ly because ( _! late ,plioc5e age & primitive traits ! specim5s are "h reg>d$ z e>ly repres5tatives ( ! subg5us ,pappogeomys4 ,discov]y ( ! upp] mol>i=m d5tition w\ld make a m precise assignm5t possible4 ,plei/oc5e ,num]\s specim5s ( geomyids f _m localities & horizons are available f ! ,plei/oc5e ( ,nor? ,am]ica4 ,specim5s ( ! g5]a ,geomys & ,?omomys are especially common4 ,few specim5s are kn[n ( ! g5]a ,or?ogeomys & ,pappogeomys1 especially f ! e>ly & middle ,plei/oc5e1 ow+1 probably1 to slight k ( ! e>ly ,plei/oc5e ( ,mxico :]e ^! two g5]a are ?\ght to h evolv$ 7see map1 ,figure #b74 ,?is lack ( k ab\t e>ly ,plei/oc5e deposits 9 ,mxico is a h&icap 9 ! pres5t in/ance s9ce ! c5t] ( diff]5tiation = sev]al ( ! mod]n g5]a is judg$ to h be5 9 ,mxico1 probably on1 & at ! edge (1 ! ,c5tral ,plateau4 ,! relative abundance ( ! rema9s ( ,geomys & ,?omomys f ,plei/oc5e deposits f>!r nor?1 & ! m>k$ abs5ce ( o!r g5]a1 may mean t ,or?ogeomys & ,pappogeomys did n range nor?w>d f s\!rn & c5tral ,mxico 9 mo/ ( ! ,plei/oc5e4 ,"o species ( ,pappogeomys ev5tually rang$ into ! s\?we/]n ,unit$ ,/ates 9 ! late ,plei/oc5e 7t[>d ! end ( ! ,wiscons97 & x occurs !re today1 b ! g5us is ess5tially ,mexican4 ,! fossil record ( ,zygogeomys1 z ! g5us is "h und]/ood1 evid5tly cont9u$ 9 ! ,unit$ ,/ates w into ! ,middle ,plei/oc5e1 dep5d+ ^u ! /ratigraphic int]pretation ( ! age ( ! ,curtis ,ran* local fauna f s\!a/]n ,arizona4 ,hibb>d 7#aieh3be7 reg>d$ ! ,curtis ,ran* local fauna z ,irv+tonian 9 age1 a local fauna t liv$ ei!r 9 ! late ,kansan glacial or ! ,y>m\?ian int]glacial1 & 8 correlation is t5tatively foll[$ "h4 ,9 deposits laid d[n lat] ?an ^? ( ,irv+tonian age no rema9s ( ,zygogeomys h be5 f\nd4 ,today a s+le species exi/s z a relic 9 ! m\nta9s ( c5tral ,mxico & ,zygogeomys may h retreat$ s\?w>d to its pres5t refugium 9 ! late ,plei/oc5e4 ,p]haps1 ,zygogeomys occurr$ 9 nor!rn ,mxico & ! s\?we/]n ,unit$ ,/ates 9 ! e>ly & middle ,plei/oc5e 7see ,fig4 #b71 occupy+ ! area betwe5 ! ranges ( ,pappogeomys to ! s\? & ,geomys to ! nor?4 ,competition ) ,pappogeomys1 & especially ,geomys1 dur+ ,irv+tonian "t may h extirpat$ ,zygogeomys ov] mo/ ( ?is area1 & by late ,plei/oc5e 7,sangamon7 mu* ( ! =m] range ( ,zygogeomys came to be occupi$ by "o or ! o!r ( its competitors4 ,! occurr5ce ( ,geomys g>banii 9 s\!rn ,cali=nia 7see ,:ite & ,d[ns1 #aifa7 & ! unid5tifi$ species ( ,geomys 9 ,aguascali5tes 7,moos]1 #aiei2 = faunal correlation1 see ,hibb>d & ,moos]1 #aifc71 bo? f deposits ( ,irv+tonian age1 supports ?is sugge/ion4 ,illu/ration3 ,,fig4 #b4 ,probable di/ribution ( ! ,subfamily ,geomy9ae 9 ! e>ly ,plei/oc5e 7late ,blancan71 depict+ major areas ( diff]5tiation ( ! mod]n g5]a4 #a4 ,?omomys #b4 ,geomys #c4 ,zygogeomys #d4 ,pappogeomys #e4 ,or?ogeomys ,?omomys ,! e>lie/ ,plei/oc5e records ( ,?omomys are mo/ly isolat$ tee?4 ,al?\gh !y c be id5tifi$ z g5us ,?omomys1 mo/ ( ! mat]ials are too fragm5t>y to be id5tifi$ to species4 ,9 ,?omomys two di/9ct patt]ns ( occlusal surfaces ( ! mol>s c be recogniz$3 ! g5]aliz$ elliptical patt]n 9 ! subg5us ,pleiso?omomys1 n unlike ! patt]n 9 o!r geomyids1 & ! pe>-%ap$ patt]n 9 ! subg5us ,?omomys1 :i* results f con/riction ( ! upp] mol>s on ! labial side & con/riction ( ! l[] mol>s on ! l+ual side4 ,"s fossils assign$ to ,?omomys 7 n exam9$ ) ?is di/9ction 9 m9d by ! p]sons :o made ! assignm5ts4 ,consequ5tly "s ( ! id5tifications n[ 9 ! lit]ature may be subject to *ange4 ,?ree occurr5ces ( ,?omomys are f ! e>ly & middle ,plei/oc5e1 ) a possible f\r? 7dep5d+ ^u ! age ( ! ,hay ,spr+s local fauna ( ,nebraska74 ,! e>lie/ ,plei/oc5e record is f ! ,broadwat]-,lisco b$s along ! ,nor? ,platte ,riv] 9 ,morrill ,c\nty1 we/]n ,nebraska4 ,possibly ! specim5 f !re 0 misid5tifi$4 ,^? b$s are ,l[] ,plei/oc5e1 & are reg>d$ by ,s*ultz & ,/\t 7#aidh3efj-efa1 #egc7 & by ,hibb>d 7#aieh3aa71 z hav+ be5 deposit$ mo/ly dur+ ! ,aftonian int]glacial4 ,!re is also "s indication t "s ( ! /rata 7 deposit$ late 9 ! ,nebraskan glaciation4 ,!re are no o!r e>ly ,plei/oc5e records ( ,?omomys4 ,savage 7#aiea3bbh7 report$ ! g5us f ! ,irv+ton local fauna1 ,alam$a ,c\nty1 ,cali=nia4 ,! specim5s 7 n id5tifi$ to species1 al?\gh !y 7 describ$ z indi/+ui%able f ,?omomys bottae4 ,paulson 7#aifa3acg7 record$ specim5s f ! ,cudahy local fauna1 ,meade ,c\nty1 ,kansas4 ,^! fragm5t>y specim5s are ref]able to ! subg5us ,?omomys1 ow+ to ! /rong con/riction ( ! mol>s1 b h n be5 id5tifi$ to species4 ,! ,cudahy is an ,irv+tonian local fauna1 & is consid]$ to h be5 deposit$ dur+ ! late ,kansan glaciation4 ,! /ratum conta9+ ! ,cudahy local fauna imm$iately und]lies ! ,pe>lette ,a%4 ,! ,cudahy mat]ial includes five isolat$ mol>s & a fragm5t>y ramus be>+ only ! premol>4 ,! g5us ,?omomys has be5 recov]$ also f ! ,hay ,spr+s local fauna 9 ,%]idan ,c\nty1 nor?we/]n ,nebraska1 by ,%ultz & ,tann] 7#aieg3ga74 ,! ,hay ,spr+s local fauna is consid]$ to h be5 deposit$ 9 late ,kansan glaciation or 9 e>ly ,y>m\? int]glacial by ,%ultz & ,tann] 7op4 cit43#fi71 or ( ,irv+tonian age2 h[ev]1 ,hibb>d 7#aieh3be7 reg>d$ ! b$s conta9+ ?is fauna z ,ill9oian 7?us po/-,irv+tonian 9 age71 & equival5t 9 age to ! ,b]5ds local fauna ( ,oklahoma & ! ,butl] ,spr+s & ,mt4 ,scott local faunas ( ,kansas4 ,! ,?omomys f ,hay ,spr+s local fauna has n be5 ref]r$ to species4 ,! relative abundance ( ,geomys1 & r>ity ( ,?omomys1 9 ,great ,pla9s fossil b$s ( e>ly & middle ,plei/oc5e is probably due to allopatric di/ributions ( ! two g5]a4 ,! ,great ,pla9s area 0 evid5tly ! c5t] ( di/ribution & diff]5tiation ( ,geomys4 ,p]haps ,?omomys evolv$ e>li] to ! we/1 9 ! ,great ,bas9 & ,pacific ,coa/al regions1 & n on ! ,great ,pla9s4 ,upp] ,plei/oc5e records ( ,?omomys are m common4 ,! g5us 0 widespread 9 b$s id5tifi$ ) ! ,ill9oian & ,sangamon & ext5d$ its range ea/w>d to ! ,atlantic ,coa/4 ,/eph5s 7#aifj3aifa7 report$ ,?omomys f ! ,doby ,spr+s local fauna1 ,h>p] ,c\nty1 nor?we/]n ,oklahoma4 ,! mat]ial 7#cd isolat$ tee?7 0 too fragm5t>y to p]mit assignm5t to species4 ,! mol>s are con/rict$ on "o side1 indicative ( ! subg5us ,?omomys1 l ! ,cudahy specim5s report$ by ,paulson 7see discussion above74 ,/eph5s errone\sly m5tion$ t ! enamel plate on ! po/]ior face ( ! upp] premol> is unique 9 ,?omomys2 ?is plate occurs also 9 ,zygogeomys4 ,! ,doby ,spr+s local fauna 0 recov]$ f b$s t h be5 id5tifi$ z ,ill9oian deposits1 & x is correlat$ ) ! ,b]5ds local fauna 9 ,beav] ,c\nty1 ,oklahoma1 & ! ,butl] ,spr+s local fauna 9 ,meade ,c\nty1 ,kansas 7see ,/eph5s1 op4 cit43 #agjj74 ,local faunas 9 ,m>yl& & ,florida ( ,ran*olabrean age include ,?omomys1 9 e in/ance ref]able to ! subg5us ,pleiso?omomys on ! basis ( uncon/rict$ mol>s4 ,?omomys potomac5sis 7,gidley & ,gaz91 #aicc71 f ,cumb]l& ,cave local fauna1 ,allegany ,c\nty 9 we/]n ,m>yl&1 is ! type ( ! g5us ,pleiso?omomys ,gidley & ,gaz9 7#aicc3ced74 ,pleiso?omomys is "h reg>d$ z a subg5us4 ,! mat]ial us$ 9 ! orig9al description includ$ f\r l[] jaws1 "o ) a complete d5tition4 ,hibb>d 7#aieh3be7 po9t$ out t ! ,cumb]l& ,cave assemblage is a composite fauna includ+ bo? glacial & int]glacial =ms4 ,he plac$ ! /ratigraphic position ( ! fauna z def9itely ,upp] ,plei/oc5e1 probably deposit$ 9 bo? ,ill9oian glaciation & dur+ ! ,sangamon int]glacial4 ,t4 potomac5sis is significantly l>g] ?an ,t4 ori5talis ,simpson 7#aibh3f71 f ! ,sab]-too? ,cave local fauna1 ,citrus ,c\nty1 ,florida4 ,simpson's mat]ial includ$ a ro/ral fragm5t ) an incisor1 premol>1 & fir/ mol>4 ,! ,sab]-too? ,cave local fauna is reg>d$ by ,kurt5 7#aife3bai7 z hav+ be5 recov]$ f ,sangamon deposits4 ,?omomys is unkn[n f ,wiscons9 deposits 9 ! ea/]n ,unit$ ,/ates1 & today ! g5us does n occur ea/ ( ! ,great ,pla9s4 ,?omomys ( ,ran*olabrean prov9cial age f ! we/]n ,unit$ ,/ates & ,mxico is kn[n only f ,wiscons9 b$s4 ,?ree ext9ct species ( ,?omomys1 all ref]able to ! subg5us ,?omomys1 h be5 describ$4 ,?omomys microdon ,s9clair 7#aije3adf71 bas$ on ! ro/ral portion ( a skull )\t a m&ible1 is f ! ,pott] ,creek ,cave local fauna1 ,%a/a ,c\nty1 ,cali=nia1 & has be5 recov]$ also f ,samwel ,cave1 ,%a/a ,c\nty1 ,cali=nia4 ,t4 microdon closely resembles ,?omomys monticola t lives 9 ! area today4 ,?omomys scudd]i ,hay 7#aiba3fad7 is f ! ,fossil ,lake 7or ,*ri/mas ,lake7 local fauna 9 c5tral ,oregon4 ,elftman 7#aica3aj-aa7 ref]r$ ^! specim5s to ,?omomys t[ns5dii1 & he consid]$ ,t4 scudd]i to be a synonym ( ,t4 t[ns5dii4 ,davis 7#aicg3aef-aeh7 disagre$ ) ,elftman conc]n+ ! taxonomic /atus ( ,t4 scudd]i1 :i* he reg>d$ z a valid species4 ,accord+ to ,davis1 ,t4 scudd]i is m closely alli$ to ,?omomys bottae ?an to ,t4 t[ns5dii4 ,cope 7#ahgh3chi2 #ahhi3afj-afe7 _h ref]r$ ! same specim5s to ,?omomys clusius 7n[ ,?omomys talpoides clusius74 ,cope consid]$ ! b$s to be ,plioc5e 9 age4 ,9 all acc\nts ( ! ,fossil ,lake local fauna up to ,hay 7#aiba71 ! specim5s ( ,?omomys 7 ref]r$ to ! species clusius1 talpoides1 or bulbivorus 7see ,elftman1 loc4 cit474 ,! ,fossil ,lake local fauna is curr5tly consid]$ z be+ ( ,ran*olabrean prov9cial age1 probably dat+ f ! ,wiscons9 glacial maximum :5 ! lake rea*$ its greate/ size4 ,! ?ird ext9ct species describ$ f ! ,wiscons9 is ,?omomys vetus ,davis 7#aicg3aef71 also f ! ,fossil ,lake local fauna 9 ,lake ,c\nty1 ,oregon4 ,davis po9t$ out t ,t4 vetus diff]s f ,t4 scudd]i ,hay1 ( ! same fauna1 9 l>g] size & o!r cranial details1 & t x is closely alli$ to ! liv+ species ,?omomys t[ns5dii1 & n to ,?omomys talpoides1 :i* is ! only species ( ,?omomys liv+ 9 ! area today4 ,?omomys t[ns5dii 0 recov]$ by ,gaz9 7#aice3bii7 f ! ,am]ican ,falls b$s 7probably ,wiscons9 deposits7 9 ,idaho4 ,?omomys talpoides is report$ f ! ,h[>d ,ran* local fauna 9 ,h>deman ,c\nty1 we/]n ,texas1 by ,dalque/ 7#aife3fi-gj71 :o ref]r$ ! isolat$ tee? to ,t4 talpoides on geographic gr\nds1 app>5tly on ! errone\s assumption t ,t4 talpoides 0 ! species ( ,?omomys ne>e/ geographically to ,h>deman ,c\nty4 ,hay 7#aibg3bei7 report$ ,?omomys fuscus ,?omomys talpoides f late ,plei/oc5e b$s ne> ,w5at*ee1 ,*elan ,c\nty1 ,wa%+ton4 ,hibb>d 7#aiea3bbi7 record$ ,?omomys talpoides f late ,plei/oc5e deposits 9 ,greeley ,c\nty1 ,kansas1 & ,walt]s 7#aieg3edj7 report$ ! same species f late ,plei/oc5e deposits 9 ,cl>k ,c\nty1 ,kansas4 ,accord+ to ,hibb>d 7#aieh3ad7 o!r rema9s report$ z ,t4 talpoides h be5 recov]$ f num]\s areas ( ,wiscons9 glacial drift 9 we/]n ,nor? ,am]ica4 ,?omomys bottae has be5 id5tifi$ f ,wiscons9 age deposits 9 we/]n ,nor? ,am]ica1 z foll[s3 ,burnet ,cave1 ,gaudalupe ,mt41 ,new ,mexico 7,s*ultz & ,h[>d1 #aice3bhj72 ,c>p9t]ia ,asphalt1 ,cali=nia 7,wilson1 #aicc;a3#gj72 ,mc,kittrick ,asphalt1 ,k]n ,c\nty1 ,cali=nia 7,j4 ,r4 ,s*ultz1 #aich3bjf72 ,ran*o ,la ,brea1 ,los ,angeles ,c\nty1 ,cali=nia 7,dice1 #aibe3abe--specim5s describ$ z a new subspecies1 ,t4 b4 occipitalis72 ,papago ,spr+s ,cave1 ,santa ,cruz ,c\nty1 ,arizona 7,sk9n]1 #aidb3aej & #aeh--probably bottae1 b possibly umbr9us on ! assumption t ! two are specifically in/ead ( subspecifically di/9ct72 ,isleta ,cave1 ,b]nalillo ,c\nty1 ,new ,mexico 7,h>ris & ,f9dley1 #aifd3aae--"s ( ^! fossils may be po/-,wiscons9 9 age72 ,pott] ,creek ,cave & ,samwel ,cave1 ,%a/a ,c\nty1 ,cali=nia 7,s9clair1 #aije3adf--;id5tifi$ z ,t4 leucodon1 n[ a subspecies ( ,t4 bottae2 also see ,hay1 #aibg3bad-bae74 ,?omomys umbr9us has be5 report$ f ,san ,josecito ,cave1 ,nuevo ,len1 ,mxico 7,russell1 #aifj3edb72 ,upp] ,b]c]ra1 ,mxico 7,hibb>d1 #aiee;a3#ea--;id5tifi$ only z ,?omomys sp41 b und\bt$ly ref]able to ,t4 umbr9us74 ,po/-,wiscons9 rema9s ( ,?omomys umbr9us are report$ by ,alv>ez 7#aifd3f7 f capa ,,ii & capa ,,iii ( ! ,cueva ,la ,nopal]a1 s\?we/]n ,hidalgo4 ,hay 7#aibg3bbb-bbc7 report$ specim5s ( ! g5us ,?omomys f ,wiscons9 deposits 9 ,hawv] ,cave1 ,eldorado ,c\nty1 ,cali=nia1 b did n assign !m to species4 ,gilmore 7#aidg3aeh7 f\nd ! rema9s ( ,?omomys umbr9us 9 cave deposits ne> ,quatro ,cinegas 9 c5tral ,coahuila4 ,^! cave deposits may h be5 laid d[n dur+ ! ,wiscons91 b m likely accumulat$ 9 ! po/-,wiscons94 ,zygogeomys ,rema9s f\nd 9 ! ,curtis ,ran* local fauna1 ,co*ise ,c\nty1 9 s\!a/]n ,arizona are reg>d$ z ( middle ,plei/oc5e age4 ,see ,gaz9 7#aidb3dha-dhd71 ,wilson 7#aicg3ci-dj71 ,hibb>d 7#aieh3be71 & ,hibb>d et al4 7#aife3eaj-eaa74 ,al?\gh "s "q z to ! exact age ( ! ,curtis ,ran* local fauna /ill seems to exi/1 mo/ au?orities on ! ,plei/oc5e agree t ! age is n ,plioc5e & t x is old] ?an ,ran*olabrean4 ,gidley 7#aibb3abb7 describ$ ! pocket goph] f\nd 9 ! ,curtis ,ran* b$s z ,geomys p>vid5s1 :i* is preoccupi$ by ,geomys p>vid5s ,br[n 7#aijh3aid71 a "n propos$ = ! pocket goph] f ! ,con>d ,fissure ( ,arkansas2 !re=e1 ,hay 7#aibg3acf7 propos$ ! "n ,geomys p]similis = ! ,curtis ,ran* species to replace ,geomys p>vid5s ,gidley4 ,geomys p]similis ,hay became ! type species ( ,gaz9's g5us ,n]t]ogeomys 7#aidb3ejg74 ,9 ?is pap]1 ,n]t]ogeomys is consid]$ to be a junior synonym ( ,zygogeomys4 ,zygogeomys p]similis is repres5t$ by a ro/ral fragm5t be>+ all ! *eek tee? on ! left side & ! upp] incisors4 ,9 addition1 two l[] jaws1 "o ) ! fir/ ?ree *eek tee?1 are ref]r$ to ! species 7see ,gaz91 #aidb3ejg74 ,! fossils id5tifi$ z ,geomys f ! ,arroyo ,san ,francisco1 ,c$azo fauna1 9 ,aguascali5tes1 ,mxico1 by ,moos] 7#aiei3dac7 may be ref]able in/ead to ,zygogeomys4 ,i h n se5 ! specim5s & no figures are available2 ,moos] /ates t a cranium 0 recov]$4 ,if ei!r ! upp] premol> or ?ird mol> is 9 place1 g5]ic id5tification c\ld be made ) reasonable c]ta9ty4 ,no o!r fossils ( ,zygogeomys h be5 uncov]$ 9 late ,plei/oc5e deposits & ! significance ( ! abs5ce ( ,zygogeomys has be5 discuss$ 9 an e>li] p>agraph ( ?is section4 ,geomys has n be5 f\nd s f> s\? z ,aguascali5tes1 b ,zygogeomys occurs f>!r s\? n[ & presumably _h a m ext5sive range on ! plateau to ! nor? 9 ! ,plei/oc5e4 ,geomys ,geomys is common 9 ,plei/oc5e deposits1 especially on ! ,great ,pla9s4 ,c]ta9ly ! c5t] ( diff]5tiation = ,geomys 0 9 ?is region1 al?\gh at times1 probably :5 conditions 7 favorable1 ,geomys exp&$ its range into adjac5t areas1 rea*+ ! ,pacific ,coa/ 9 ,irv+tonian times & ! ,atlantic ,coa/ at ! "t ( ! ,ill9oian glaciation4 ,! e>lie/ ,plei/oc5e records ( ! g5us are f ! ,great ,pla9s4 ,mc,grew 7#aidd3di7 describ$ ,geomys qu9ni f ! ,s& ,draw local fauna1 ,br[n ,c\nty1 ,nebraska1 consid]$ by ,hibb>d 7#aieh3aa7 to be ,nebraskan 9 age4 ,z m5tion$ 9 ! acc\nt ( ,plioc5e geomyids1 ,geomys qu9ni occurs also 9 ! late ,plioc5e deposits ( s\?we/]n ,kansas4 ,also1 ,geomys qu9ni occurs 9 ! ,broadwat]-,lisco local fauna ( ,morrill & ,g>d5 c\nties1 we/]n ,nebraska 7,b>b\r & ,s*ultz1 #aicg3c2 ,s*ultz & ,/\t1 #aidh3efj-efc2 ,s*ultz et al41 #aiea3 table #a74 ,! ,broadwat]-,lisco is curr5tly reg>d$ z ,aftonian deposits 7,s*ultz & ,/\t1 loc4 cit42 ,hibb>d1 #aieh3aa74 ,hibb>d 7#aief3agd7 id5tifi$ ,geomys qu9ni f ! ,de] ,p>k local fauna1 probably deposit$ dur+ ! e>ly ,aftonian int]glacial1 ( ,meade ,c\nty1 ,kansas4 ,/ra9 7#aiff3cf7 describ$ ,geomys pa5eburs>ius on ! basis ( fossils obta9$ f e>ly ,plei/oc5e deposits ( ! ,hudspe? local fauna f we/]n ,hudspe? ,c\nty 9 ! ,trans-,pecos ( ,texas4 ,! ,hudspe? fossils 7 probably deposit$ dur+ ! ,aftonian int]glacial4 ,f ,k+man ,c\nty1 ,kansas1 ,hibb>d 7op4 cit43 #afd7 recov]$ isolat$ tee? ( ,geomys f ! ,dixon local fauna1 reg>d$ by him 7op4 cit43#aec-aed7 z deposit$ dur+ ! late/ ,nebraskan glaciation1 & correlat$ by him ) ! ,s& ,draw local fauna ( ,nebraska4 ,hibb>d 7#aieh3aa7 lat] reg>d$ ! ,dixon z a transitional fauna betwe5 ,nebraskan & ,aftonian4 ,! rema9s ( ,geomys f ! ,dixon are kn[n only f isolat$ tee?4 ,! tee? are small1 & sugge/ t a small] species ( ,geomys may h occurr$ along ) ! m common & l>g] ,g4 qu9ni dur+ ! e>ly ,plei/oc5e 7see discussion beyond ( ! ,saund]s ,geomys74 ,geomys qu9ni 0 widespread & common ?r\gh\t ! c5tral ,great ,pla9s f ! late ,plioc5e 7,rexroad fauna7 ?r\gh ! e>ly ,plei/oc5e 7,nebraskan & ,aftonian deposits74 ,hibb>d 7#aief3agi7 ref]r$ ! pocket goph] rema9s tak5 f ! ,saund]s local fauna 9 ,meade ,c\nty1 ,kansas1 to ,geomys tob95sis1 a small species hav+ cont9u\s enamel b&s ar\nd ! l[] premol> 9 y\ng] specim5s4 ,! ,saund]s local fauna 0 deposit$ 9 ! late ,aftonian & is y\ng] ?an ! ,de] ,p>k local fauna discuss$ above4 ,paulson 7#aifa3ach7 lat] po9t$ out t ! ,saund]s ,geomys is di/9ct f ,geomys tob95sis2 h5ce1 ! small pocket goph] f ! ,saund]s local fauna is probably an unnam$ species1 p]haps m closely alli$ to pa5eburs>ius ?an to qu9ni4 ,! small ,geomys report$ f ! ,aftonian ,broadwat]-,lisco local fauna ( ,nebraska 7,s*ultz & ,/\t1 #aidh3efc7 may also be ! same z ! ,saund]s pocket goph]1 b ! small] adult specim5s occurr+ 9 ! same b$ ) l>g] specim5s probably are females & ! l>g] specim5s males4 ,9 all liv+ ,geomy9i females h small] skulls ?an males4 ,! ,irv+tonian prov9cial age is curr5tly reg>d$ z ,middle ,plei/oc5e & includes ! late ,kansan glaciation 7t "p occurr+ aft] ! glacial maximum7 & ! ,y>m\?ian int]glacial 7see ,hibb>d et al41 #aife3eab-ead74 ,! ,irv+tonian prov9cial age1 !re=e1 foll[s ! late ,blancan prov9cial age ( ! e>ly ,plei/oc5e & is succe$$ by ! ,ran*olabrean prov9cial age ( ! late ,plei/oc5e4 ,no specim5 ( an ,irv+tonian ,geomys is ref]able to any liv+ species4 ,two ,irv+tonian species h be5 describ$4 ,hibb>d 7#aidd3gce7 nam$ ,p>ageomys tob95sis ,geomys tob95sis f ! ,tob9 local fauna ( ,russell ,c\nty1 ,kansas4 ,?is species s9ce has be5 report$ f ! ,cudahy local fauna ( ,meade ,c\nty1 ,kansas 7,paulson1 #aifa3acg74 ,hibb>d 7#aief3ahc7 also id5tifi$ z ,geomys tob95sis ! pocket goph] recov]$ f ! ,saund]s local fauna1 a late ,aftonian deposit ( ,meade ,c\nty1 ,kansas1 & r$uc$ ! te*nical "n ,p>ageomys f g5]ic to subg5]ic rank4 ,paulson 7op4 cit43#ach7 po9t$ out t ! ,saund]s specim5s diff] f ,g4 tob95sis1 & he1 !re=e1 re/rict$ ! "n to ! small ,geomys ( ! ,cudahy & ,tob9 local faunas ( ,irv+tonian prov9cial age4 ,g4 tob95sis is m>k$ly small] ?an ! ,blancan ,g4 qu9ni4 ,! ,cudahy & ,tob9 local faunas are ( approximately ! same age1 & pres5tly bo? are includ$ 9 "o unit1 ! ,cudahy fauna4 ,! ,cudahy fauna is consid]$ to h be5 deposit$ 9 late ,kansan z x occurs 9 /rata imm$iately bel[ ! ,pe>lette a%4 ,rec5tly1 ,:ite & ,d[ns 7#aifa3h7 describ$ a new ,irv+tonian species1 ,geomys g>banii1 f ! middle ,plei/oc5e ,vallecito ,creek local fauna ( ,san ,diego ,c\nty1 ,cali=nia4 ,_m well pres]v$ fossils ( ! new species 7 recov]$4 ,geomys g>banii is ( m$ium size 7approximately ! size ( "o ( ! l>g] subspecies ( ,g4 burs>ius71 & significantly l>g] ?an ! ,irv+tonian ,geomys tob95sis ( ! ,great ,pla9s4 ,! ,vallecito ,creek occurr5ce ( ,geomys is ! fir/ au!nticat$ record f ! ,pacific ,coa/ region4 ,mat!w 7#aijb3cbj7 errone\sly ref]r$ rema9s ( ,?omomys to ! g5us ,geomys 9 8 revis$ li/ ( ,cope's e>li] report on ! ,fossil ,lake 7or ,silv] ,lake7 fauna 7see discussion ( ,?omomys above74 ,a numb] ( ,irv+tonian fossil rema9s ( ,geomys h n be5 id5tifi$ ) p>ticul> species4 ,hibb>d 7#aida;a3#bjf7 f\nd ,geomys 9 ! ,bor*]s local fauna 7deposit$ 9 ! "t ( ! ,y>m\?ian int]glacial7 ( ,meade ,c\nty1 ,kansas4 ,also1 ,geomys has be5 report$ f sev]al sites 9 ,nebraska4 ,s*ultz & ,tann] 7#aieg3fg7 report$ ,geomys f ! ,angus fossil qu>ry 9 ,nuckolls ,c\nty1 s\?-c5tral ,nebraska4 ,! ,angus fossils 7 f\nd 9 s$im5ts ( ! ,sappa ,=mation consid]$ by ,s*ultz & ,tann] to be a ,y>m\?ian deposit4 ,fossil qu>ries 7,hay ,spr+s1 ,ru%ville1 & ,gordon7 along ! s\? side ( ! ,niobr>a ,riv] ,valley 9 ,%]idan ,c\nty1 ,nebraska1 h also provid$ records ( geomyids4 ,bo? a l>ge & small species ( ,geomys h be5 report$ f ! m rec5tly excavat$ ,ru%ville & ,gordon sites 7,s*ultz & ,/\t1 #aidh3efb-efg1 & table #c74 ,9 view ( ! great disp>ity 9 size ow+ to sex1 ^! may actually be males & females ( ! same species1 z m5tion$ above4 ,! "n ,hay ,spr+s has be5 us$ 9 ref]5ce to all ?ree sites4 ,! ages ( ! ,hay ,spr+s sites are approximately ! same1 b _! correlation is pres5tly "u debate4 ,s*ultz & ,tann] 7#aieg3fh-ga7 ma9ta9 t ! fossils are di/9ctly middle ,plei/oc5e1 & t !y 7 deposit$ dur+ late ,kansan glaciation1 or p]haps f e>ly ,y>m\?ian into e>ly ,ill9oian1 ) ! l>ge/ conc5tration com+ f ! ,sappa s&s ( pre-,ill9oian 7,y>m\?7 age4 ,hibb>d 7#aieh3be71 bas+ 8 op9ion on ! pres5ce ( ,microtus p5nsylvanicus1 & ! /age ( evolution ( o!r species 9 ! assemblage1 reg>ds ! ,hay ,spr+s sites z probably ,ill9oian deposits1 b c]ta9ly no old] ?an t4 ,moos] 7#aiei3dac7 id5tifi$ z ,geomys ! pocket goph] f ,irv+tonian deposits 9 ,arroyo ,san ,francisco 7loc4 no4 #e7 ne> ! city ( ,aguascali5tes1 ,mxico4 ,z sugge/$ else:]e 9 ?is acc\nt1 ^! fossils may be ref]able to ,zygogeomys r ?an ,geomys4 ,! ,irv+tonian prov9cial age ( ?is fauna 0 e/abli%$ by ,hibb>d & ,moos] 7#aifc3bde-bej74 ,o!r alleg$ occurr5ces h rec5tly be5 compil$ by ,alv>ez 7#aife3ai-bj74 ,maldonado-,ko]dell 7#aidh3bj7 not$ f\r fossil occurr5ces ( ! g5us ,geomys 9 ,mxico4 ,two ( ^! f ,san ,josecito ,cave 9 ,nuevo ,len h s9ce be5 id5tifi$ ) ! g5]a ,or?ogeomys & ,pappogeomys 7,russell1 #aifj3edc-edh72 ! ?ird li/$ by ,maldonado-,ko]dell f ne> ,ameca1 ,jalisco1 0 bas$ on ,br[n's 7#aiab3afg7 m5tion ( "s bones suppos$ly ( ! family ,geomyidae1 & ! f\r? ref]s to pocket goph] rema9s f ! ,ho*tals von ,mexiko li/$ z ,geomys by ,freud5b]g 7#aiba3aci74 ,8 g5]ic id5tification is d\btful & ! specim5s %\ld be comp>$ ) ,mexican g5]a ( ! ,geomy9ae4 ,upp] ,plei/oc5e records ( ,geomys also are common4 ,upp] ,plei/oc5e is "h und]/ood to include late ,ill9oian1 ,sangamon & ,wiscons9 deposits2 all are consid]$ to be ( ,ran*olabrean prov9cial age 7see ,hibb>d et al41 #aife3eab-eae7 & po/-,irv+tonian4 ,! pres5ce ( rema9s ( ,bison &_/or ,microtus p5nsylvanicus are curr5tly consid]$ mammalian index fossils ( ,ran*olabrean faunas4 ,9 ! ,ill9oian1 ,geomys ext5d$ its range to ! ,atlantic ,coa/ 9 ! s\!a/]n ,unit$ ,/ates4 ,! ea/]n & we/]n species-gr\ps evid5tly 7 isolat$ ?r\gh\t mu* ( ! late ,plei/oc5e1 &1 !re=e1 evolv$ sep>ately4 ,( ! two1 ! ea/]n1 or p9etis1 species-gr\p seems to h rema9$ some:at m g5]aliz$1 & ! we/]n1 or burs>ius1 species-gr\p has become m specializ$4 ,! ,ran*olabrean ,geomys f deposits 9 ! s\!a/]n ,unit$ ,/ates are ref]able 7see ,ray1 #aifc3cbe7 to ,geomys p9etis4 ,m>% 7#ahga3aba7 describ$ ,geomys bisulcatus f ! ,nor? ,prong ( ! ,l\p ,riv] 7ne> ,camp ,?omas71 ,nebraska4 ,^! b$s are also t]m$ ! ,l\p ,=k or ,l\p ,riv] fossil b$s 7see discussion on p4 #dhe71 & !y lie along ! upp] rea*es ( ! ,middle ,l\p ,riv] 9 ,?omas ,c\nty 7ne> ,s5ea71 ,hook] ,c\nty 7ne> ,mull571 & s\!a/]n ,*]ry ,c\nty 7probably ! ,nor? ,prong b$s nor?we/ ( ,mull574 ,^! b$s 7 at fir/ ?\ght to be ( ,mioc5e age1 b lat] 7 reg>d$ z e>ly ,plioc5e 7see ,s*ultz & ,/\t1 #aidh3efb-eff = a hi/orical acc\nt ( exp$itions to ^! fossil sites74 ,s*ultz & ,tann] 7#aieg3ga-gb7 po9t$ out t ! pr9cipal fossilif]\s b$s 9 ! ,middle ,l\p region are ( middle to late ,plei/oc5e age1 ) mo/ ( ! fossils com+ f ! ,crete s& & silt b$s :i* are probably e>ly ,ill9oian deposits1 &1 !re=e1 y\ng] ?an ! ,hay ,spr+s faunas4 ,"s fossils may h come f ! ,sappa deposits dat$ by ,s*ultz & ,tann] 7loc4 cit47 z mo/ly ,y>m\?ian deposits4 ,geomys bisulcatus1 judg+ f ! orig9al description & ,hibb>d's discussion ( ! cotypes 7#aied3ceg71 does n diff] significantly f ,geomys burs>ius4 ,h[ev]1 ,geomys bisulcatus is t5tatively reta9$ z a valid species4 ,bas$ on ! evid5ce cit$ above x seems unlikely t ,geomys bisulcatus occurr$ 9 pre-,irv+tonian times z (t5 sugge/$ 9 ! lit]ature4 ,! g5us ,geomys has be5 id5tifi$ 9 sev]al faunas ( ,ill9oian age1 all f ! ,great ,pla9s4 ,/eph5s 7#aifj3aifa7 report$ ! g5us f ! ,doby ,spr+s local fauna 9 ,h>p] ,c\nty1 ,oklahoma1 & ,/>rett 7#aief3aahh7 report$ x f ! ,b]5ds local fauna 9 ,beav] ,c\nty1 ,oklahoma4 ,s*ultz 7#aife3bdi7 assign$ #ba isolat$ tee?1 includ+ six incisors1 f ,butl] ,spr+s local fauna 7consid]$ by him to be late ,ill9oian1 foll[+ ! glacial maximum7 to ,geomys cf4 burs>ius4 ,hibb>d & ,taylor 7#aifj3afg7 report$ a baculum t5tatively id5tifi$ z t ( ,geomys f ! e>ly ,ill9oian ,butl] ,spr+s local fauna 7includ+ ! ,adams fauna7 ( ,meade ,c\nty1 ,kansas4 ,hibb>d 7#aifc3bjf7 record$ ! g5us ,geomys f ! ,mt4 ,scott local fauna 7late ,ill9oian deposits7 ( ,meade ,c\nty1 ,kansas2 ! specim5s probably are ref]able to ! liv+ species burs>ius4 ,f ,mc,pherson ,c\nty1 ,kansas1 ,hibb>d 7#aieb3g7 report$ ! g5us ,geomys f ! ,k5tuck ,assemblage1 :i* he 7#aieh3be7 reg>d$ z a composite ( ,ill9oian & ,sangamon species4 ,specific id5tification ( ! ,ill9oian pocket goph]s is unc]ta91 prim>ily due to ! fragm5t>y nature ( ! mat]ial4 ,on ! basis ( d5tal *>act]s alone mo/ specim5s c\ld be ref]r$ to ,g4 burs>ius2 h[ev] ! taxonomic /atus ( ,g4 bisulcatus is 9 d\bt1 & m complete mat]ial may indicate t ! ,ill9oian goph]s are specifically di/9ct f ! liv+ species4 ,consequ5tly1 mo/ au?ors1 includ+ myself1 h made no attempt to ref] ^! specim5s to species4 ,nev]!less1 ! ,ill9oian ,geomys f ! ,great ,pla9s is m closely alli$ to ! liv+ species ( ,geomys ?an x is to ! e>li] ,irv+tonian species4 ,geomys burs>ius has be5 collect$ f a numb] ( ,sangamon fossil sites on ! ,great ,pla9s4 ,al?\gh specific id5tification ( specim5s ( ,geomys f ,ill9oian faunas is unc]ta91 ! ,great ,pla9s ,geomys f ,sangamon & lat] deposits probably is ref]able to ! liv+ species z ,hibb>d & ,taylor 7#aifj3afe7 po9t$ out4 ,!y f\nd no diff]5ce betwe5 ,geomys recov]$ f ! ,crag9 ,qu>ry local fauna 7e>ly ,sangamon7 ( ,meade ,c\nty1 ,kansas1 & ! liv+ species ,geomys burs>ius4 ,isolat$ tee? ( ! same species 7 collect$ f ! ,j+lebob local fauna ( ,meade ,c\nty1 ,kansas 7,hibb>d1 #aiee;b3#bjf71 a fauna ( ! late ,sangamon4 ,hibb>d 7#aidc3bdj7 also record$ ! g5us ,geomys 7ref]able to ,g4 burs>ius7 f ! ,rezabek local fauna ( ,l9coln ,c\nty1 ,kansas4 ,accord+ to ,s*ultz et al4 7#aiea3f & table #a7 ! g5us ,geomys occurs 9 buri$ or fossil soils ( ,sangamon age1 ly+ j above ! ,lovel& ,loess1 9 ,nebraska4 ,no specific localities 7 giv5 by !m1 nor 7 any p>ticul> specim5s m5tion$4 ,dalque/ report$ ,geomys burs>ius f two ,sangamon faunas 9 nor!rn ,texas4 ,! species is repres5t$ 9 ! ,w>d ,qu>ry local fauna ( ,cooke ,c\nty1 ,texas 7#aifb;a3#db71 & ! ,good ,creek local fauna ( ,fo>d ,c\nty1 ,texas 7#aifb;b3#ege74 ,geomys burs>ius has be5 report$ f ,wiscons9 fossil deposits ( ! ,great ,pla9s & adjac5t areas z foll[s3 ,jones local fauna1 ,meade ,c\nty1 ,kansas 7,hibb>d & ,taylor1 #aifj3fd-ff72 ,two ,creeks ,=e/ b$s ( ! ?ird int]/adial soils =m$ betwe5 ,c>y & ,mankato glaciations1 late ,wiscons9 7,s*ultz et al41 #aiea3h & table #a72 ,cita ,canyon local fauna 9 ! nor!rn "p ( ! ,panh&le ( ,texas 7,johnson & ,savage1 #aiee3ci72 ,h[>d ,ran* local fauna ( ,h>deman ,c\nty 9 nor?we/]n ,texas 7,dalque/1 #aife3gj72 ,quitaque local fauna ( ,motley ,c\nty1 ,texas 7,dalque/1 #aifd3eja72 ,cle> ,creek local fauna ( ,d5ton ,c\nty 9 nor?-c5tral ,texas 7,slaught] & ,rit*ie1 #aifc3abj72 ,b5 ,frankl9 local fauna1 ( late ,wiscons9 b$s along ! ,nor? ,sulphur ,riv] 9 ,delta ,c\nty1 ,,ne ,texas 7,slaught] & ,hoov]1 #aifc3acg72 ,bulv]de ,cave 7,hay1 #aibj3adj2 #aibd3bdg7 & ,fries5hahn ,cave 7,tamsitt1 #aieg3cba71 bo? 9 ,bex> ,c\nty1 s\?-c5tral ,texas2 ,alton1 ,ill9ois 7,hay1 #aibc3cch-cci72 ,wiscons9 drift ( ,ill9ois1 )\t m5tion ( specific locality 7,bad] & ,te*t]1 #aiei3agb72 ,wiscons9 drift ( s\?we/]n ,wiscons9 & nor!a/]n ,i[a 7,hay1 op4 cit43#cdc72 ,wiscons9 drift ne> ,gal5a1 ,ill9ois1 & m\? ( ,platte ,riv] 9 ea/]n ,nebraska 7,leidy1 #ahfi3djf74 ,br[n 7#aijh3aid7 describ$ ,geomys p>vid5s f ! ,con>d ,fissure1 9 nor!rn ,arkansas4 ,hibb>d 7#aieh3be7 conclud$ t ! ,con>d ,fissure fauna repres5ts a glacial /age1 probably ! ,ill9oian1 & ,hibb>d et al4 7#aife3eaj-eaa7 reg>d$ ! fauna z a composite includ+ bo? ,irv+tonian & ,ran*olabrean elem5ts4 ,:ite & ,d[ns 7#aifa3ba7 consid]$ ,g4 p>vid5s to be a subspecies ( ,geomys burs>ius4 ,! fir/ ,plei/oc5e occurr5ce ( ,geomys 9 ! s\!a/]n ,unit$ ,/ates is f ! ,r$dick ,i deposits report$ by ,gut & ,ray 7#aifc3cbe71 :o f\nd ! rema9s ( ,geomys p9etis among ! fossils compris+ ! rod5t b$s ( ,m>ion ,c\nty1 ,florida4 ,gut & ,ray t5tatively id5tifi$ ! b$s z ,ill9oian1 b ,kurt5 7#aife3bai7 reg>d$ ! ,r$dick ,i fauna z e>ly ,sangamon4 ,simpson 7#aibh3b7 report$ ,geomys floridanus p9etis f ,sab]-too? ,cave deposits ( ,citrus ,c\nty1 ,florida4 ,! ,sab]-too? ,cave 7or ,lecanto ,cave7 local fauna is consid]$ by ,kurt5 7op4 cit43#bai7 also to be a ,sangamon deposit4 ,geomys floridanus p9etis 0 report$ f ! ,sem9ole ,field deposits by ,simpson 7#aibi3efc72 bo? ,simpson & ,kurt5 7op4 cit43#bba7 agre$ t ! ,sem9ole ,field fauna is ma9ly late ,wiscons91 al?\gh sub-,rec5t fossils occur at ! tops ( ! b$s4 ,ray 7#aieh3dcj7 collect$ rema9s ( ,geomys p9etis f ! ,melb\rne ,bone ,b$ ( ,brev>d ,c\nty1 ,florida4 ,! ,melb\rne local fauna is consid]$ to be f ,wiscons9 deposits by ,kurt5 7op4 cit43#bbj74 ,! ea/]n species ( ,geomys 7 probably d]iv$ f ,great ,pla9s /ock t rea*$ ! s\!a/]n ,coa/al ,pla9s 9 e>ly ,ran*olabrean 7,ill9oian7 "t4 ,pres5tly !re is no contact betwe5 ! ea/]n & we/]n populations ( ! g5us1 & x is assum$ t disjunction occurr$ z a result ( ,wiscons9 glaciation4 ,x is int]e/+ to note t ! g5us ,?omomys occurr$ 9 ?is region at approximately ! same "t2 bo? g5]a occur 9 ,sab]-too? ,cave deposits4 ,pappogeomys ,! g5us ,pappogeomys is n kn[n f ,plei/oc5e deposits old] ?an ! ,wiscons9 glaciation1 b a pre-,plei/oc5e occurr5ce 9 ! ,b5son b$s ( ,arizona 7see discussion ( ! ,plioc5e above7 %[s t ,pappogeomys _h be5 diff]5tiat$ by late ,plioc5e "t4 ,! abs5ce ( ,pappogeomys1 beg9n+ 9 ! e>ly ,plei/oc5e & cont9u+ well into ! late ,plei/oc5e1 is attribut$ to ! s\!rn di/ribution ( ! g5us1 :]e its range probably 0 c5t]$ on ! ,c5tral ,plateau ( ,mxico4 ,! paucity ( e>ly & middle ,plei/oc5e deposits f ?is critical region prev5ts any def9ite /atem5ts ab\t phyletic developm5t )9 ! g5us4 ,all ( ! late ,plei/oc5e records p]ta9 to ! subg5us ,cratogeomys 7long 9 use z a g5]ic "n b 9 ! pres5t pap] r$uc$ to subg5]ic rank 9 ! g5us ,pappogeomys74 ,s*ultz & ,h[>d 7#aice3bhj7 f\nd ,cratogeomys ,pappogeomys ca/anops 9 ,burnett ,cave 9 ! ,guadalupe ,m\nta9s ( s\?-c5tral ,new ,mexico4 ,! ,burnett deposits are probably late ,wiscons9 7see ,s*ultz & ,tann]1 #aieg3ge1 = discussion ( ! age ( ^! deposits bas$ on c>bon-#ad te/s74 ,^! writ]s 7loc4 cit47 also ref]r$ ! m&ible ( a small pocket goph] to ! g5us ,pappogeomys subg5us ,pappogeomys4 ,h[ev]1 nei!r g5]a nor subg5]a ( ! tribe ,geomy9i c be di/+ui%$ on ! basis ( _! inf]ior d5titions4 ,judg+ f ! di/ribution ( ! mod]n geomy9es1 x seems unlikely t ! subg5us ,pappogeomys has occurr$ beyond its pres5t range 9 ! late ,plei/oc5e2 !re=e ! small m&ible is mo/ likely t ( a "y individual ( ,pappogeomys ca/anops4 ,russell 7#aifj3edc7 ref]r$ specim5s collect$ at ,san ,josecito ,cave 9 ,nuevo ,len1 ,mxico1 to ! gr\p ( small subspecies ,cratogeomys ,pappogeomys ca/anops4 ,also1 ,russell 7loc4 cit47 id5tifi$ a ro/ral fragm5t z ( ! g5us ,cratogeomys subg5us ,cratogeomys al?\gh ! fragm5t _h a comb9ation ( features diff]5t ?an 9 any nam$ species ( ! g5us2 he did n "n ! fragm5t z a new species1 pref]r+ to wait = additional mat]ial t c\ld cl>ify its taxonomic relation%ips4 ,hibb>d 7#aiee;a3#eb-ec7 id5tifi$ ,cratogeomys ,pappogeomys tylorh9us f ! ,bec]ra ,sup]ior deposits 9 ! valley ( ,tequixquic 9 ! nor!rn "p ( ! /ate ( ,mxico4 ,! ,wiscons9 age ( ^! b$s sugge/s an e>li] ,plei/oc5e d]ivation ( ! gymnurus-gr\p ( species4 ,sev]al specim5s ( ! subg5us ,cratogeomys h be5 report$ f b$s ( late/ ,wiscons9 7c]ta9ly aft] ! glacial maximum7 or po/-,wiscons9 age4 ,gilmore 7#aidg3aeh7 f\nd fossil rema9s ( ,cratogeomys ,pappogeomys ca/anops commonly 9 ,quat]n>y cave deposits on ! m\nta9 slopes 9 ! vic9ity ( ,cuatro ,cinegas1 9 c5tral ,coahuila4 ,^! deposits actually may be ( po/-,wiscons9 orig9 7see discussion above74 ,alv>ez 7#aifd3h7 obta9$ fragm5ts ( ,cratogeomys ,pappogeomys tylorh9us f sub-,rec5t deposits ( ,capa ,,iii 9 ! ,cueva ,la ,nopal]a 9 s\?we/]n ,hidalgo1 ,mxico4 ,pappogeomys m]riami lives 9 ! area today4 ,may]-,oakes 7#aiei3cgc7 report$ rema9s ( ,cratogeomys ,pappogeomys m]riami f levels eight & elev5 ( ! excavations at ,el ,risco ,,ii1 9 ! nor!rn "p ( ,mexico ,city4 ,! ages ( ^! deposits are unkn[n to me1 b !y probably are no old] ?an late ,wiscons9 ) mo/ ( ! b$s dat+ f ! po/-,wiscons94 ,or?ogeomys ,?is g5us is n kn[n f ! ,plei/oc5e1 except = its occurr5ce 9 ! ,san ,josecito cave deposits ( s\?we/]n ,nuevo ,len1 ,mxico 7,russell1 #aifj3edd74 ,al?\gh ,or?ogeomys does n occur 9 ! imm$iate vic9ity ( ! cave at ! pres5t "t1 ! nor!rn limits ( its range is ne>by 9 s\!rn ,tamaulipas4 ,! ,or?ogeomys f ,san ,josecito ,cave diff]s f liv+ species1 & has be5 nam$ ,het]ogeomys ,or?ogeomys on]osus ,russell 7loc4 cit471 & is evid5tly ref]able to ! subg5us ,het]ogeomys4 ,z m5tion$ be=e1 ! ,san ,josecito ,cave local fauna repres5ts deposits ( ,wiscons9 glaciation4 ,,hi/ory ,,( ,,classification ,! acc\nt ( ! ,tucan or ,indian mole by ,h]n&ez 7sometimes li/$ z ,f]n&ez7 9 #afea probably is ! e>lie/ publi%$ "o ( a geomyid 7see ,m]riam1 #ahie3bja2 ,c\es1 #ahgg3fjg-fjh74 ,l9naeus 9 #ageh did n m5tion geomyids4 ,9 #aggb1 ,k]r describ$ ,h]n&ez's ,tucan "u ! "n ,sorex mexicana on ! basis ( ,h]n&ez's acc\nt )\t hav+ se5 any specim5s4 ,li*t5/e9 9 #ahbg appli$ ! te*nical "n ,ascomys mexicana to ?ree specim5s collect$ by ,deppe f unkn[n localities on ! tablel& ( ,mxico4 ,m]riam 7loc4 cit47 po9t$ out t ! "n mexicanus ( ,li*t5/e9 9 #ahbg is a nom5 nudum1 & t x is preoccupi$ by mexicanus us$ by ,k]r 9 #agib4 ,! latt] c n be te*nically id5tifi$ ) any p>ticul> species ( geomyid4 ,b>tram 9 #agia wrote ( ! pocket goph] ( ,florida1 )\t =mally describ+ x4 ,! fir/ available te*nical "n is ,mus burs>ius ( ,%aw 9 #ahjj4 ,raf9esque 9 #ahag propos$ ! fir/ g5]ic names = ! geomyids :5 he describ$ ,geomys & ,diplo/oma4 ,9 #ahci1 ,wat]h\se ref]r$ ! g5us ,geomys to 8 family ,arvicolidae1 consid]$ by him to be a subgr\p ( muroids4 ,9 #ahda1 he sugge/$ t ,geomys 0 relat$ to ,ba?y]gus & ,spalax4 ,wat]h\se 9 #ahdh 7p4 #h7 treat$ ! pocket goph]s z a subgr\p ( rod5ts "u ! gr\p "n ,saccomy9a1 9 :i* he includ$ ! g5]a ,het]omys1 ,saccomys1 ,p]ogna?us1 & ,dipodomys4 ,h5ce1 ,wat]h\se 0 ! fir/ to recognize ! relation%ip betwe5 ! het]omyids & geomyids4 ,9 ! next ye> ,g]vais erect$ ! family ,pseudo/omidae = a gr\p ( specializ$ squirrels to include ,geomys & ,?omomys & ! same g5]a 7at lea/ 9 "p7 ( het]omyids t ,wat]h\se classifi$ 9 ! family ,saccomy9a4 ,9 #ahci ! "n ,?omomys 0 propos$ by ,maximilian 7,wi$-,neuwi$74 ,all ( ! g5]ic names previ\sly propos$ = pocket goph]s 7 consid]$ by subsequ5t au?ors to be synonyms ( ,geomys4 ,a ?ird family "n1 ,sciurospalacoides1 0 propos$ by ,br&t 7#ahee3ahh7 :o ref]r$ ,geomys & ,?omomys to t family4 ,he plac$ 8 new family phylog5etically betwe5 ! family ,sciuridae & ! family ,spalacoides 7a gr\p 9 :i* ,br&t includ$ ! g5]a ,spalax1 ,sipheus1 & ,ellobius74 ,br&t took exception to ! classification ( ,wat]h\se 7#ahdh71 :o unit$ ! geomyids & het]omyids 9 "o family4 ,br&t plac$ ! het]omyid g5]a 9 o!r gr\ps3 ,p]ogna?us 9 ! ,muridae1 & ,macrocolus ,dipodomys 9 ! ,macrol9i1 a subfamily ( ! family ,dipodoides4 ,mod]n classification ( ! pocket goph]s beg9s ) ,baird 9 #aheh4 ,! important classifications are summ>iz$ 9 ,table #a2 a few t d n dep>t ess5tially f ^? li/$ h be5 omitt$ ow+ to limit$ space = ! tabul> arrangem5t1 b are discuss$ 9 ! foll[+ acc\nt4 ,baird probably 0 /rongly influ5c$ by ! arrangem5t propos$ by ,wat]h\se 9 #ahdh1 b 0 oppos$ to sep>at+ geomyids f het]omyids z 0 done by ,br&t4 ,baird 0 conv9c$ ( ! close relation%ip ( ! geomyids & het]omyids1 & ref]r$ bo? gr\ps to "o family1 ! ,saccomyidae1 z ,wat]h\se _h done e>li]4 ,9 ord] to recognize ! morphological specializations he us$ two subfamilies1 ,geomy9ae & ! ,saccomy9ae4 ,9 ! #bj ye>s t foll[$1 "s au?ors foll[$ ,br&t & o!rs foll[$ ,baird4 ,gill1 9 #ahgb 7p4 #ga71 propos$ a classification ess5tially l ,baird's ( #aheh1 b ,gill rais$ ,baird's subfamilies to ! rank ( family 7see ,table #a74 ,9 ref]r+ all pocket goph]s to ! ,geomyidae1 ,gill us$ t "n z a family t]m = ! fir/ "t4 ,also he e/abli%$ ! sup]family ,saccomyoidea to include 8 two families1 ,geomyidae & ,saccomyidae2 !re=e1 ! ,saccomyoidea 0 equival5t to ! gr\p ,saccomy9a ( ,wat]h\se 7#ahdh7 & ! ,saccomyidae ( ,baird 7#aheh74 ,c\es 7#ahgg71 9 8 classic monograph ( ! ,geomyidae foll[$ ! arrangem5t propos$ by ,gill 9 treat+ ! pocket goph]s z a family4 ,al/on 9 #ahgf propos$ ano!r classification bas$ on ,baird 7#aheh71 ) two subfamilies1 ! ,geomy9ae & ! ,het]omy9ae1 unit$ toge!r 9 ! family ,geomyidae2 ?us1 he recogniz$ t ! g5us ,saccomys ,frdric ,cuvi]1 #ahbc1 0 a synonym ( ,het]omys ,desm>e/1 #ahag1 z _h be5 po9t$ out by ,gray 7#ahfh3bja7 & ,pet]s 7#ahgd3cef74 ,c\es 7#ahgg3dhg-dij7 ackn[l$g$ ! invalidity ( ! g5us ,saccomys1 b refus$ to give up ! "n 9 sup]g5]ic classification4 ,w+e1 fir/ 9 #ahhg & subsequ5tly 9 #aibd1 classifi$ ! geomyids & het]omyids toge!r 9 ! family ,saccomyidae z did ,baird 9 #aheh1 & l ,c\es1 ,w+e too ignor$ ! synonymy ( ,saccomys ) ,het]omys & insi/$ on reta9+ ! te*nical t]ms ,saccomyidae & ,saccomy9i4 ,up to ! "t ( ,m]riam's classic revision ( ! ,rec5t ,geomyidae 9 #ahie all ! kn[n species ( liv+ pocket goph]s 7 ref]r$ to two g5]a1 ,geomys & ,?omomys4 ,m]riam describ$ mu* new mat]ial1 especially f ,mxico & ,c5tral ,am]ica1 & propos$ sev5 new g5]a 7see ,table #a74 ,8 complete & detail$ /udy ( ! d5titions & o/eology ( ! skull rema9s today z ! def9itive "w on ?is subject1 & is ! po9t :]e mo/ /udies ( ! ,geomyidae mu/ beg94 ,8 treatm5t ( ! ,rec5t g5]a surviv$ = #eb ye>s )\t *ange until ,hoop] 7#aidf3cig7 arrang$ ,platygeomys z a synonym ( ,cratogeomys4 ,h[ev]1 ,m]riam's g5]a h be5 recogniz$ 9 all subsequ5t classifications except = ! curr5t review 7see ,table #a74 ,cope describ$ ! fir/ kn[n fossil geomyids 9 #ahgh1 & publi%$ an excell5t review ( ! two g5]a1 ,pleurolicus & ,entoptycus1 9 #ahhd 7pp4 #hee-hgj1 pl4 #fd1 figs4 #a-i74 ,bo? g5]a 7 recov]$ f ! ,john ,day ,mioc5e deposits ( ,oregon4 ,cope did n propose a new sy/ematic arrangem5t ( ^! geomyids1 b ref]r$ !m to ! family ,saccomyidae & m5tion$ t ! ,saccomyidae 0 equival5t to ! family ,geomyidae ( ,al/on4 ,w+e1 9 #ahhg1 foll[$ ,cope 9 ref]r+ ,pleurolicus & ,entoptycus to ! ,saccomyidae along ) ! liv+ g5]a ,?omomys & ,geomys4 ,mill] & ,gidley 7#aiah71 9 _! synopsis ( ! sup]g5]ic gr\ps ( rod5ts1 propos$ a new subfamily1 ,entopty*9ae1 to include ! div]g5t ,mioc5e pocket goph]s4 ,mill] & ,gidley also reviv$ ! old subfamily ,geomy9ae ( ,baird 7#aheh71 b re/rict$ its application to ! mod]n pocket goph]s & _! imm$iate ance/ors4 ,9 #aicf1 ,a4 ,e4 ,wood revis$ ! taxa ( ! subfamily ,entopty*9ae1 & describ$ ! fir/ ,mioc5e g5us1 ,dikkomys1 ( ! ,geomy9ae4 ,he foll[$ ! sup]g5]ic classification ( ,mill] & ,gidley 7#aiah74 ,! rec5t classifications ( ,simpson 7#aide7 & ,wood 7#aiee7 h comb9$ ! classifications ( ,m]riam 7#ahie7 & ,wood 7#aicf74 ,wood 7#aiee7 br\ght up to date ! li/ ( g5]a1 includ+ ^? t 7 describ$ aft] ! publication ( ,simpson's classification 7#aide74 ,9 ,table #a1 ! li/ ( g5]a is pr9cipally f ,simpson 7#aide7 b g5]ic names us$ by ,wood 7#aiee7 are includ$4 ,?is is ! curr5tly accept$ classification4 ,! new classification propos$ 9 ?is pap] 7see ,table #a7 includes ?ree tribes propos$ z v]tical units2 !y are int5d$ to /ress ! phyletic tr5ds 9 ! kn[n evolution>y sequ5ces by plac+ imm$iate ance/ors toge!r ) _! desc5dants4 ,pliogeomys is plac$ 9 ! same tribe 7,geomy9i7 z ,zygogeomys1 ,geomys1 ,or?ogeomys1 & ,pappogeomys4 ,t tribe includes ! mo/ specializ$ ,geomy9ae4 ,zygogeomys1 ,geomys1 ,or?ogeomys1 & ,pappogeomys are l9eages result+ f a ,plei/oc5e radiation 9 :i* all ! l9eages div]g$ f a common ,plioc5e ance/or4 ,! radiation ( ! ,geomy9i 0 well "u way by ! close ( ! late ,plioc5e4 ,al?\gh ,pliogeomys may n be ! actual ance/or1 x closely resembles ! primitive morphotype4 ,,table #a4--;,hi/ory ( ! classification ( ! ,sup]family ,geomyoidea ,baird #aheh ,gill #ahgb ,w+e #ahhg ,m]riam #ahie ,c\es #ahgg & #aibd ,ell]man #aidj ---------------------------------------- ----------------------- ,family ,family ,family ,family ,saccomyidae ,geomyidae ,saccomyidae ,geomyidae ---------------------------------------- ----------------------- ,subfamily ,gr\p ,geomy9ae ,geomy9i -- -- -- -- -- -- -- -- -- ---- -- -- -- -- -- -- -- -- -- -- - ,?omomys ,?omomys ,?omomys ,?omomys ,zygogeomys ,geomys ,geomys ,geomys ,geomys ,or?ogeomys ,het]ogeomys ,macrogeomys ,pappogeomys ,cratogeomys ,platygeomys -- -- -- -- -- -- -- -- -- ---- -- -- -- -- -- -- -- -- -- -- - 99,pleurolicus 99,entopty*us ---------------------------------------- ----------------------- ,gr\p ,gymnopty*9e9999 ,gymnopty*us ---------------------------------------- ----------------------- ,subfamily ,family ,gr\p ,saccomy9ae ,saccomyidae ,saccomy9i ---------------------------------------- -------------------- ,wood #aice ,simpson #aide ,names us$ 9 ,wood #aicf ,wood #aiee pres5t pap] ---------------------------------------- --------------------- ,family ,family ,family ,geomyidae ,geomyidae ,geomyidae ---------------------------------------- --------------------- ,subfamily ,subfamily ,subfamily ,geomy9ae ,geomy9ae ,geomy9ae -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- - ,tribe ,dikkomy9i 99,dikkomys 99,dikkomys 99,dikkomys 99,pliosaccomys 99,pliosaccomys ,tribe ,?omomy9i 99,pleiso?omomys 99,pleiso?omomys ,?omomys ,?omomys ,?omomys ,tribe ,geomy9i 99,pliogeomys 99,pliogeomys ,zygogeomys ,zygogeomys 99,n]t]ogeomys ,zygogeomys ,geomys ,geomys 99,p>ageomys ,geomys ,or?ogeomys ,or?ogeomys ,het]ogeomys ,het]ogeomys ,or?ogeomys ,macrogeomys ,macrogeomys ,pappogeomys ,pappogeomys ,cratogeomys ,cratogeomys ,pappogeomys ,platygeomys ,platygeomys -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- - ,subfamily ,subfamily ,subfamily ,entopty*9ae ,entopty*9ae ,entopty*9ae 99,pleurolicus 99,pleurolicus 99,pleurolicus 99,gregorymys 99,gregorymys 99,gregorymys 99,grang]imus 99,grang]imus 99,grang]imus 99,entopty*us 99,entopty*us 99,entopty*us ---------------------------------------- --------------------- ,geomyidae ,geomyidae inc]tae s$is inc]tae s$is 99,gidleumys 99,diplolophus 99,diplolophus 99,griphomys 99,griphomys ---------------------------------------- --------------------- ,family ,family ,family ,het]omyidae ,het]omyidae ,het]omyidae ---------------------------------------- --------------------- 99 ,d5otes ext9ct g5]a4 9999 ,w+e includ$ 9 8 family ,saccomyidae ! gr\p ,gymnopty*9e & ! conta9$ g5us ,gymnopty*us ,cope1 #ahgc1 :i* g5us curr5tly is plac$ 9 ! family ,eomyidae4 ,! type ( ,gymnopty*us ,cope1 #ahgc1 is synonym\s ) ,is*yromys ,leidy1 #ahef1 & ! valid "n = ! g5us is ,adjidaumo ,hay1 #ahii4 ,pliosaccomys1 on ! o!r h&1 repres5ts ! t]m9al /ages ( a long tr5d t began ) ! ,dikkomys-l ,geomy9ae ( ! e>ly ,mioc5e4 ,9 ?is l9eage1 ! rate ( evolution 9 ! d5tition & ! skull 0 sl[2 !re=e1 ! diff]5ces betwe5 e>ly ,mioc5e 7,dikkomys7 & middle ,plioc5e 7,pliosaccomys7 are n great & ! two are unit$ into ! tribe ,dikkomy9i4 ,! ,dikkomy9i is ! ance/ral geomy95 trunk f :i* ! mod]n gr\ps h div]g$4 ,! ,plioc5e ance/or ( ,?omomys is unkn[n b probably resembl$ ,pliosaccomys1 ) :i* x may h be5 a contempor>y4 ,?omomys is ! lea/ specializ$ ( ! mod]n ,geomy9ae1 &1 consequ5tly1 %[s ! mo/ resemblance to ! ance/ral tribe4 ,! specializations ( ,?omomys1 h[ev]1 cle>ly preclude its ref]5ce to ! tribe ,dikkomy9i2 !re=e1 x is set ap>t 9 ! monotypic tribe ,?omomy9i4 ,t tribe has n und]gone an adaptive radiation comp>able to t ( ! tribe ,geomy9i or t ( ! ,entopty*9ae 9 ! e>ly ,mioc5e4 ,"h1 = ! fir/ "t1 ,?omomys is set ap>t 9 classification f ! o!r liv+ pocket goph]s4 ,m]riam's g5]a ,or?ogeomys1 ,het]ogeomys1 & ,macrogeomys are closely relat$4 ,ea* ( ^! taxa is reta9$ z a subg5us ( a s+le g5us1 ,or?ogeomys4 ,"s species ( ,macrogeomys seem to be m closely alli$ to ! subg5us ,or?ogeomys & o!rs to ! subg5us ,het]ogeomys4 ,a revision ( ! g5us is ne$$2 x might %[ t ! curr5tly recogniz$ subg5]a are artificial1 & t a diff]5t arrangem5t ( ! species w\ld m cle>ly express _! evolution>y relation%ips4 ,! subg5us ,het]ogeomys seems to be ! mo/ ne>ly uni=m ( ! subg5]a1 & x is ! lea/ specializ$4 ,radiation )9 ! g5us may h begun relatively rec5tly1 b ! _m special adaptations = tropical environm5ts sugge/ t ! g5us has be5 9 ! ,neotropical ,zone a long "t4 ,!re=e1 discov]y ( an e>ly di*otomy f ! common ance/ral /ock ( ! tribe w\ld come z no surprise4 ,n]t]ogeomys ,gaz9 "h is arrang$ z a junior synonym ( ,zygogeomys4 ,bo? are less specializ$ ?an any ( ! o!r ,geomy9i1 except ,pliogeomys4 ,! s+le liv+ species 7,zygogeomys tricopus7 is obvi\sly a relic4 ,its range is small4 ,! two subspecies diff] only 9 m9or features4 ,! liv+ species does h a few unique *>act]i/ics1 only to be expect$ 9 ! surviv+ species ( a long phyletic l9eage4 ,"s ( ^! are specializations4 ,o!rwise1 ,zygogeomys & ,n]t]ogeomys are closely relat$ & ! latt] is be/ plac$ z a synonym ( ! =m]4 ,bo? are admitt$ly closely relat$ to ,geomys4 ,zygogeomys & ,geomys %>e sev]al *>act]s1 p>ticul>ly primitive ones2 !re is consid]able p>allelism1 especially m>k$ 9 ,irv+tonian species ( ,geomys4 ,nev]!less1 ,geomys is m specializ$1 p>ticul>ly 9 ! d5tition1 & x has develop$ "s ,pappogeomys-l specializations4 ,zygogeomys has reta9$ m ( ! primitive *>act]s ( ! tribe4 ,a /rong case c\ld be made = recogniz+ only "o g5us1 ,geomys1 conta9+ ,zygogeomys z "o ( two subg5]a4 ,nev]!less1 ! *>act]s sep>at+ ,zygogeomys & ,geomys are ( consid]able importance & ,i consid] ! two k9ds to be di/9ct g5]a4 ,! species ( ,geomys1 bo? liv+ & ext9ct1 =m a di/9ct & well-m>k$ gr\p4 ,! g5us is less primitive 9 mo/ respects ?an ,zygogeomys & ,or?ogeomys & x is less specializ$ ?an ,pappogeomys1 exclud+ ! ance/ral /ock 7subg5us ,pappogeomys74 ,"s specim5s ( species ( ,irv+tonian age 7,geomys tob95sis & ,geomys g>banii1 especially ! =m]7 reta9 primitive enamel plates z does ,zygogeomys2 b ?is is true ( only a small p]c5tage ( ! individuals4 ,also ! adult d5tal patt]n develop$ some:at lat] 9 ontog5y 9 ^! middle ,plei/oc5e species ( ,geomys ?an 9 ei!r ,rec5t or late ,plioc5e & e>ly ,plei/oc5e repres5tatives 7,geomys pa5eburs>ius1 ,geomys qu9ni7 ( ! g5us4 ,:e!r ^! features repres5t a /age 9 ! evolution ( ! late ,plei/oc5e & ,rec5t species or a t]m9al /age 9 memb]s ( a /]ile & primitive bran* ( ! ma9 l9e ( evolution ( ,geomys is unc]ta94 ,at pres5t ,i favor ! latt] explanation1 & view ,g4 pa5eburs>ius & ,g4 qu9ni z e>ly progressive species t evolv$ d5tal specializations t 7 ma9ta9$ 9 ! ma9 l9e ( phylog5y4 ,hibb>d propos$ ! g5]ic "n ,p>ageomys 7#aidd3ee71 b lat] reg>d$ x z a subg5us ( ,geomys 7#aief3ahb7 t includes ^? species reta9+ cont9u\s enamel b&s until relatively late 9 ontog5y2 no o!r diff]5ces h be5 not$4 ,:5 ! e>ly phylog5y ( ,geomys is bett] und]/ood1 ,p>ageomys may s]ve z a subg5]ic taxon 9 :i* ! primitive species ( ,geomys c be gr\p$1 b z ( n[ ,p>ageomys is arrang$ z a synonym ( ,geomys4 ,pappogeomys & ,cratogeomys also =m a natural gr\p4 ,_! close relation%ip is be/ reflect$ 9 =mal taxonomy by includ+ !m 9 ! same g5us4 ,_! dissimil>ities are ( ! sort t sep>ate a primitive ance/ral l9eage f a div]g5t & progressively m specializ$ assemblage4 ,! fossil record is inadequate1 & ,i c only speculate t ,cratogeomys div]g$ f primitive ,pappogeomys-/ock 9 ! e>li] ,plei/oc5e1 at lea/ be=e ! end ( ! ,irv+tonian4 ,cratogeomys probably orig9at$ on ! ,mexican ,plateau & probably und]w5t its subsequ5t evolution !re4 ,! liv+ species ( ! subg5us ,pappogeomys are evid5tly relics ( ! ance/ral /ock ( ! g5us4 ,hoop] 7#aidf3cig71 ,i ?9k correctly1 consid]$ ,platygeomys z cong5]ic ) ,cratogeomys1 al?\gh ! highe/ degree ( specialization ( ! g5us is atta9$ 9 ^? species =m]ly class$ 9 ! g5us ,platygeomys4 ,ev5 s1 9 my op9ion1 ! diff]5ces are insuffici5t to w>rant ev5 subg5]ic recognition4 ,,classification ,family ,,geomyidae ,gill1 #ahgb ,rod5ts ( ! sup]family ,geomyoidea specializ$ = completely fossorial life 7e>ly ,plioc5e to ,rec5t72 specializ$ e>li] 7late8 ,oligoc5e & e>ly ,mioc5e7 = semi-fossorial habits2 body ?ickset1 fusi=m )\t app>5t neck 79 mod]n geomyids72 legs %ort2 =elegs especially /\t2 eyes & e>s small 7p9na r$uc$ to inconspicu\s cre/ conceal$ b5ea? pelage72 tail tactile1 %ort] ?an head & body2 lips clos+ beh9d incisors2 *eek p\*es ext]nal1 fur-l9$2 baculum rodlike1 ar*$1 hav+ exp&$ quadri=m platelike base2 pelage long1 s(t )\t und]fur1 cov]+ body 9 ?ick coat 79 "s species ( ,or?ogeomys scant1 h>% or scatt]$ bri/les72 color v>y+ f pale t9ts ( buffy 7almo/ :ite7 to metallic black4 ,skull ?ick-wall$1 massive1 angul>1 relatively broad1 & flatt5$2 di/9ctly mur9e =m1 b hav+ zygomasset]ic /ructure ( advanc$ sciuromorphs1 includ+ small infraorbital canal 7t transmits no "p ( masset] muscle7 & well-develop$1 broad zygomatic plate2 zygomata massive & widely fl>+1 jugals /\t2 ro/rum robu/1 relatively broad & deep1 & )\t evid5ce ( transv]se canal 7z 9 ,het]omyidae72 ant]ior projection ( nasals only slightly exce$+ t ( upp] incisors2 int]orbital region usually con/rict$1 n>r[] ?an ro/rum2 ant]ior op5+ ( infraorbital canal f> =w>d on side ( ro/rum1 ab\t half way betwe5 zygomatic plate & upp] incisor & j beh9d premaxill>y-maxill>y suture1 its op5+ c\nt]sunk 9 oblique sulcus 7= protection f muscle contraction72 po/orbital process lack+1 except = rudim5t>y knoblike projection 9 subg5us ,macrogeomys2 palate relatively n>r[1 its deeply sculptur$ surface slop+ /eeply d[nw>d po/]iorly caus+ region support+ maxill>y too?-r[ to be m>k$ly depress$2 palat9e bone r$uc$1 =m+1 on two abruptly diff]5t levels1 po/]ior m>g9 ( h>d palate beh9d too?-r[s2 p>ietals compress$ & n>r[1 & mo/ ( c]ebral cavity ro($ by squamosals 79 "s species squamosals ov]lap lat]al p>ts ( p>ietals72 tympanic bullae completely inf]ior 9 position & fully ossifi$1 ext]nal meatus be+ develop$ lat]ally z elongat$ tube2 ma/oid n inflat$1 b broadly expos$ at po/]olat]al m>g9 ( ! skull2 occiput l>ge1 its surface usually rugose1 & p>occipital processes l>ge & flangelike1 at lea/ 9 advanc$ gr\ps 7e>ly ,plioc5e to ,rec5t72 ramus relatively %ort & /\t1 hav+ di/9ct cre/ & ridges = muscle atta*m5ts2 coronoid process well develop$1 erect2 articul> condyle prom95t2 angul> process prom95t1 reflect$ lat]ally1 & 9 mod]n gr\ps lat]al ext5sion protrud+ f po/]ior bord] ( ramus ne>ly at "r angle2 capsule = root ( l[] incisor1 prom95t betwe5 angul> process & articul> condyle4 ,ant]ior surface ( incisors broad & flat1 always smoo? on l[] tee?1 b ei!r smoo? or groov$ on upp] tee? dep5d+ on taxon2 *eek tee? hypsodont1 becom+ progressively high] cr[n$ 9 mod]n gr\ps1 root$ 9 primitive gr\ps 7late8 ,oligoc5e to middle ,plioc5e71 rootless & ev]-gr[+ 9 mod]n gr\ps 7late ,plioc5e to ,rec5t72 upp] & l[] premol>s p]si/5tly bicolumn>2 upp] & l[] mol>s bicolumn> only 9 primitive gr\ps 7late8 ,oligoc5e & e>ly ,mioc5e71 becom+ progressively monocolumn> 9 advanc$ gr\ps 7e>ly ,plioc5e to ,rec5t71 primitive bicolumn> patt]n be+ reta9$ on occlusal surface only 9 e>ly /ages ( ontog5y & 9 ?ird mol> ?r\gh\t life2 enamel patt]n ( occlusal surface ( *eek tee? bas$ on sextitub]culate prototype 7see ,wood & ,wilson1 #aicf3chh-cia71 hav+ cusps arrang$ 9 two transv]se r[s ( ?ree cusps ea*1 except+ ?ree ant]ior cusps ( premol>s t are arrang$ 9 trefoil1 especially on p#d 7sometimes only "o or two1 r ?an ?ree1 cusps develop 9 a p>ticul> set1 especially 9 p#d71 conules abs5t2 proto/yle & endo/yle 9 upp] tee? & proto/ylid & hypo/ylid 9 l[] tee? =m$ f c+ulum2 cusps ( ea* r[ unit+ ) we> into transv]se enamel lophs 7or lophids71 ea* too? hav+ two lophs1 "o on ant]ior column1 protoloph & protolophid1 & "o on po/]ior column1 hypoloph & hypolophid1 t unite ) additional we> =m+ cont9u\s enamel b&2 enamel lack+ on sides ( ea* column 9 advanc$ l9eages1 !reby re/rict+ enamel to ant]ior & po/]ior walls2 ) extreme r$uction1 po/]ior plates ( upp] tee? &1 m commonly1 ant]ior plates ( l[] mol>s1 miss+4 ,d5tal =mula3 #a_/a1 #j_/j1 #a_/a1 #c_/c4 ,key to ! ,subfamilies ( ,geomyidae ,a ,angul> process ( ramus mo/ly bel[ alveol> level ( m&ibul> too?-r[2 patt]n ( premol> l t ( mol>s1 consi/+ ( two subequal cre/s unit$ at "o or bo? m>g9s ( too?2 mol>s p]si/5tly bicolumn>2 mol>i=m tee? always root$4 ,subfamily ,entopty*9ae p4 #eac ,a ,angul> process ( ramus mo/ly above level ( m&ibul> too?-r[2 patt]n ( p]mol> unlike t ( mol>s1 consi/+ ( two prisms diff]+ 9 size & unit$ at _! mid-po9ts b nev] at ei!r m>g92 mol>s progressively monocolumn>1 except = e>ly ,mioc5e =ms2 mol>i=m tee? root$ only 9 primitive g5]a 7late8 ,oligoc5e to middle ,plioc5e71 & rootless & ev]-gr[+ 9 lat] g5]a 7late ,plioc5e to ,rec5t74 ,subfamily ,geomy9ae p4 #ead ,subfamily ,,entopty*9ae ,mill] & ,gidley1 #aiah ,ant]ior face ( upp] incisor usually smoo?1 sometimes be>+ fa9t groove 9 c5t] or ne> m$ial m>g9 ( too?1 at lea/ 9 ,gregorymys2 *eek tee? hypsodont1 m$ium to high cr[n$1 & root$ 9 all b ,entopty*us 7has rootless1 ev]-gr[+ tee?72 *eek tee? id5tical 9 =m1 premol>s resembl+ mol>s & l[] *eek tee? mirror images ( upp] tee?2 cr[ns biprismatic1 hav+ two columns jo9$ at edge ( protom]es 7= description ( t]m1 see discussion ( primitive morphotype on page #ecg7 & ) p]si/5t lat]al fissure betwe5 !m2 lat]al re-entrant fold deep1 p5etrat+ at lea/ half wid? ( cr[n1 f ext]nal side 9 upp] tee? & int]nal side 9 l[] tee? 79 specializ$ g5us ,entopty*us lophs1 ^u additional we>1 jo9 also at edge ( p>am]es1 ?us unit+ columns at bo? ends & !reby enclos+ int]ior "p ( lat]al fissure z a transv]se fossette 9 c5t] ( too?72 enamel inve/m5t ( prisms usually complete1 includ+ inflection bord]+ re-entrant folds1 occlusal patt]n becom+ int]rupt$ ) we> only 9 ,entopty*us1 :]e enamel disappe>s fir/ f sides ( cr[ns 7foll[+ union ( ant]ior & po/]ior columns at bo? sides7 & lat]1 9 f9al /ages ( attrition1 f ant]ior wall ( l[] mol>s & po/]ior wall ( upp] mol>s4 ,maxill>y bone )\t pron\nc$ v]tical dep? 9 "p support+ *eek tee?1 its inf]ior bord] only slightly l[] ?an inf]ior bord] ( premaxill>y & alveol> lips ( mol>i=m tee? consequ5tly approximately level )1 or slightly bel[1 alveol> lip ( upp] incisor2 squamosal )\t lat]al expansion1 !re=e1 meatal tube ( auditory bulla sep>at$ f zygomatic process ( squamosal by deep1 well-develop$ po/gl5oid not*2 angul> "p ( m&ible bel[ alveol> level ( m&ibul> *eek tee?2 angul> process only slightly reflect$ lat]ally2 coronoid process l[1 tip only slightly above condyle4 ,= in=mation conc]n+ ! /ructure & relation%ips ( ! kn[n g5]a1 & = acc\nts ( species1 see ,wood 7#aicf74 ,a li/ ( ! nam$ g5]a 9 ord] ( specialization is z foll[s3 99,pleurolicus ,cope1 #ahgh4 ,proc4 ,am]4 ,phil4 ,soc41 #ah3ff4 99,gregorymys ,wood1 #aicf4 ,am]4 ,mus4 ,novit41 #hff3i4 99,grang]imus ,wood1 #aicf4 ,am]4 ,mus4 ,novit41 #hff3ac4 99,entopty*us ,cope1 #ahgh4 ,proc4 ,am]4 ,phil4 ,soc41 #ah3fd4 ,five new species h be5 describ$ s9ce ,wood's 7#aicf7 revision4 ,!y are3 ,pleurolicus clasoni ,mac,donald 7#aifc3ahj72 ,gregorymys kayi ,wood 7#aiej3cce72 ,gregorymys montan5sis ,hibb>d & ,ke5mon 7#aiej3aih72 ,grang]imus dakot5sis ,mac,donald 7#aifc3ahb72 ,grang]imus sell>dsi ,hibb>d & ,wilson 7#aiej3fbc74 ,subfamily ,,geomy9ae ,baird1 #aheh ,ant]ior face ( upp] incisor primitively smoo?1 grooves consi/5tly develop$ only 9 "o mod]n l9eage 7,geomy9i72 *eek tee? hypsodont1 primitively root$ & hav+ cr[n ( m$ium height 7late ,oligoc5e to middle ,plioc5e71 be+ high] cr[n$1 rootless & ev]-gr[+ 9 mod]n l9eages 7late ,plioc5e to ,rec5t72 primitively cr[ns ( *eek tee? biprismatic1 hav+ two columns jo9$ at mid-po9ts by n>r[ i/hmus & entire cr[n %ea!d 9 cont9u\s b& ( enamel2 premol>s reta9+ primitive biprismatic =m1 ant]ior & po/]ior columns nev] unit+ at edge ( protom]es or p>am]es1 & ) bo? lat]al re-entrant folds p]si/5t ?r\gh\t life2 primitive biprismatic patt]n becom+ decid$ly modifi$ 9 mol>s 7except 9 ,m#c71 hav+ two prisms progressively unit+ into "o column by r$uction & loss ( lat]al inflections1 primitive biprismatic patt]ns be+ reta9$ only 9 e>ly /ages ( ontog5y2 ?ird upp] mol>s reta9+1 at lea/ p>tially1 primitive bicolumn> patt]n 7except 9 ,?omomy9i71 ) relatively broad i/hmus & horizontally %all[ re-entrant folds1 l+ual fold sometimes want+2 enamel patt]n becom+ discont9u\s 7late ,plioc5e to ,rec5t7 ow+ to loss ( enamel f sides ( ea* column2 rema9+ enamel re/rict$ to ant]ior & po/]ior plates1 or cutt+ blades1 & enamel bord]+ lat]al inflections 9 premol>s 7consid]+ bo? sides toge!r1 ^! plates con/itute ess5tially two transv]se cutt+ blades72 enamel patt]n ( ,m#c v>y+1 dep5d+ on taxon2 ) specialization1 ant]ior plates ( l[] mol>s & po/]ior plates ( upp] premol> & mol>s may be r$uc$ or lo/2 except 9 primitive species 7e>ly ,mioc5e71 no enamel fossettes reta9$ 9 adult d5titions4 ,maxill>y bone hav+ pron\nc$ v]tical dep? 9 "p support+ *eek tee?1 inf]ior bord] ar*+ d[nw>d well bel[ inf]ior bord] ( premaxill>y2 consequ5tly1 alveol> lips ( mol>i=m tee? decid$ly bel[ level ( alveol> lip ( upp] incisor2 squamosal ) m>k$ lat]al expansion at exp5se ( po/gl5oid not*2 not* compress$ & r$uc$ betwe5 meatal tube ( auditory bulla & zygomatic process ( squamosal2 angul> "p ( m&ible mo/ly above alveol> level ( m&ibul> *eek tee?2 angul> process reflect$ lat]ally at "r angles to axis ( ramus & develop$ into heavy knoblike projection2 coronoid process well develop$1 tip decid$ly high] ?an condyle2 fossorial specializations rem>kably well develop$ 9 advanc$ l9eages1 degree ( specialization ( primitive ,mioc5e species unkn[n b probably only semi-fossorial z 9 ,entopty*9ae4 ,key to ! ,tribes ( ! ,geomy9ae ,a ,enamel inve/m5t complete & un9t]rupt$1 ev5 9 f9al 7adult7 /ages ( we>2 *eek tee? root$1 ) cr[ns ( m$ium height2 ?ird l[] mol> biprismatic1 ! two columns sep>at$ by inn] & out] re-entrant folds z 9 l[] premol>4 ,tribe ,dikkomy9i p4 #eae ,a ,enamel inve/m5t incomplete & discont9u\s1 r$uc$1 at lea/ 9 f9al 7adult7 /ages ( we>1 to int]rupt$ enamel plates2 *eek tee? rootless & ev]-gr[+ 7except 9 ext9ct g5us ,pliogeomys71 cr[ns ( maximum height2 ?ird l[] mol> monoprismatic1 )\t trace ( inn] & out] re-entrant folds z 9 fir/ & second l[] mol>s4 ,b ,upp] incisors smoo?1 occasionally ) a f9e indi/9ct groove ne> inn] m>g9 ( too?2 =m ( ?ird upp] mol> same z ,m#a & ,m#b1 monoprismatic1 ant]opo/]iorly compress$1 & hav+ transv]se enamel plates on bo? ant]ior & po/]ior faces1 & )\t sugge/ion ( ei!r labial or l+ual re-entrant folds2 basitemporal fossa abs5t 7except = a %all[ depression 9 "o ,rec5t species1 ,t4 t[ns5dii72 =efoot small & n>r[ ) claws n elongat$ = digg+4 ,tribe ,?omomy9i p4 #eah ,b ,upp] incisors groov$1 be>+ ei!r "o or two sulci2 =m ( ?ird upp] mol> di/9ctly diff]5t f ,m#a & ,m#b1 fully or p>tially biprismatic 7) a few exceptions discuss$ beyond71 )\t m>k$ ant]opo/]ior compression 7ei!r subtriangul>1 elongat$1 suborbicul> or quadri=m 9 cross-section1 b n elliptical z 9 ,m#a & ,m#b71 & hav+ typical transv]se ant]ior plate & two lat]al plates 7v>y+ 9 _! developm5t1 dep5d+ on taxa71 b no po/]ior plate1 & ) lat]al re-entrant folds usually develop$1 especially labial inflection 7al?\gh sometimes m9ute 9 a few species1 z describ$ beyond72 basitemporal fossa well-develop$1 al?\gh occasionally %all[ or abs5t 7primitive species ( ,zygogeomys72 =efoot l>ge & broad1 ) elongat$ claws = digg+4 ,tribe ,geomy9i p4 #eba ,tribe ,,dikkomy9i1 new tribe ,g5otype4--,dikkomys ,wood1 #aicf4 ,*ronologic & geographic range4--,e>ly to ,middle ,plioc5e 7e>ly ,arik>eean to mid-,hemphillian7 9 we/]n ,unit$ ,/ates4 ,kn[n f ,mioc5e fossil sites 9 ,montana1 ,s\? ,dakota1 & ,nebraska & ,plioc5e sites 9 ,s\? ,dakota1 ,oregon1 ,nevada1 & s\!rn ,cali=nia4 ,= precise localities see acc\nts ( ,dikkomys & ,pliosaccomys beyond4 ,diagnosis4--,small ,geomy9ae2 lack+ specializations ( m advanc$ tribes2 upp] incisors smoo?1 at lea/ 9 ,pliosaccomys2 mol>i=m tee? always root$ & hav+ cr[ns ( m$ium height2 enamel inve/m5t ( *eek tee? complete & un9t]rupt$ 9 all /ages ( we>2 cr[ns ( mol>s primitively biprismatic1 hav+ two columns unit$ at mid-po9ts1 ?us =m+ n>r[ i/hmus sep>at+ lat]al re-entrant folds z 9 premol>s1 &1 ) we>1 also unit+ second>ily at protom]es 7) exception ( ?ird l[] mol>s71 consequ5tly1 isolat+ remnant ( t inflection z %all[ fossette 7columns unit+ fir/ at protom]es 9 ,pliosaccomys72 ant]ior & po/]ior columns ( fir/ & second mol>s1 bo? above & bel[1 becom+ progressively unit$ into "o column 9 advanc$ ,dikkomy9i 7e>ly & middle ,plioc5e71 b m#c 7,m#c unkn[n7 reta9+ primitive biprismatic patt]n1 ) columns jo9$ at c5t]s b nev] at protom]es 7= details ( d5tition see g5]ic acc\nts72 m&ible /\t1 its angle mo/ly above m&ibul> too?-r[2 masset]ic ridge l[2 basitemporal fossa b>ely disc]nable 9 "s fragm5ts ( ,pliosaccomys2 po/cranial skeleton unkn[n4 ,key to ! ,g5]a ( ! ,tribe ,dikkomy9i ,a ,mol>s biprismatic ?r\gh\t life2 ant]ior & po/]ior lophs ( fir/ & second mol>s 9 pre-f9al /ages ( we> unit+ fir/ at _! mid-po9ts & lat] at edge ( protom]es2 ant]ior lophid ( l[] premol> hav+ di/9ct ant]oext]nal inflection4 ,g5us ,dikkomys p4 #eaf ,a' ,fir/ & second mol>s becom+ monoprismatic 9 f9al 7adult87 /ages ( we>1 biprismatic only 9 pre-f9al /ages ( we>2 ?ird mol>s p]si/5tly biprismatic2 ant]ior & po/]ior lophs ( fir/ & second mol>s unit+ fir/ at edge ( protom]es2 ant]ior lophid ( l[] premol> lack+ ant]oext]nal inflection4 ,g5us ,pliosaccomys p4 #eag ,g5us ,dikkomys ,wood #aicf4 ,dikkomys ,wood1 ,am]4 ,mus4 ,novit41 #hff3bf1 ,july #b4 ,type4--,dikkomys mat!wi ,wood1 #aicf1 f ,l[] ,h>rison deposits ne> ,agate1 ,si\x ,c\nty1 ,nebraska4 ,*ronologic range4--,e>ly ,mioc5e1 f e>ly ,arik>eean 7,l[] ,h>rison local fauna ( ,nebraska7 to middle ,mioc5e1 late ,hem+=dian 7,upp] ,rosebud local fauna1 ,s\? ,dakota1 & ! ,deep ,riv] ,=mation1 ,montana74 ,accord+ to ,mac,donald 7#aifc3adi-aej71 ! ,upp] ,rosebud is middle ,mioc5e r ?an e>ly ,mioc5e4 ,description4--,size small1 ab\t z 9 small k9ds ( ,?omomys2 kn[n only f fragm5t>y m&ible1 includ+ mol>i=m d5tition 9 place1 & isolat$ *eek tee?1 includ+ ,m#a 7see ,wood1 #aicf3bf-bh & fig4 #cb2 ,galbrea?1 #aidh3caf-cag & fig4 #a2 & ,black1 #aifa3ac-ad & fig4 #eh72 upp] incisors unkn[n2 *eek tee? hyposodont1 p]si/5tly root$1 & hav+ cr[ns ( m$ium height comp>$ ) ,rec5t geomyids2 enamel inve/m5t complete & un9t]rupt$ 9 all mol>i=m tee? 9 all /ages ( we>2 ,p#d unkn[n1 b probably =m$ l p#d2 p#d p]si/5tly biprismatic1 two cr[ns jo9$ at mid-po9ts by relatively n>r[ i/hmus sep>at+ lat]al re-entrant folds2 ant]ior lophid ( p#d hav+ di/9ct ant]oext]nal inflection2 mol>s also biprismatic ?r\gh\t life2 two lophids ( l[] mol>s fir/ unit+ at mid-po9ts z 9 p#d1 &1 ) additional we>1 m#a & m#b second>ily unit+ at edge ( protom]es & =m+ isolat$ enamel fossette betwe5 po9t ( connection 7detail$ description ( /ages ( we> discuss$ 9 acc\nt ( phylog5y ( subfamily72 m#c p]man5tly jo9$ at mid-po9t only1 )\t lat]al union at edge ( protom]es2 upp] mol>s1 judg+ by ,m#a 7,m#b & ,m#c unkn[n71 hav+ same patt]n z l[] mol>s1 b fir/ union ( lophs decid$ly on l+ual side ( c5t]1 consequ5tly1 l+ual re-entrant fold small2 ,m#a probably develop+ ,u-patt]n 9 advanc$ /ages ( we> by union ( protom]es1 ) m9ute l+ual fossette develop+ 9 transition z lophs second>ily become unit$ at l+ual edge ( columns2 m&ible /\t & geomyidlike2 masset]ic ridge weakly develop$2 basitemporal fossa abs5t4 ,evid5tly1 ,dikkomys mat!wi is m primitive ?an ,dikkomys woodi4 ,! modifi$ ,h-patt]n 9 m#a & m#b1 ) ! metalophid & hypolophid jo9$ at bo? _! mid-po9ts & also at _! protom]es 7by union ( ! proto/ylid & hypo/ylid 9 ! l[] d5tition71 is p]si/5t ?r\gh\t life4 ,!re=e1 ! enclos$ enamel fossette is n eradicat$ ) we>4 ,9 m#a & m#b ( ,dikkomys woodi1 ! fossette is %all[]1 &1 at lea/ 9 advanc$ /ages ( we>1 x w\ld disappe>1 !re=e1 =m+ a ,u-patt]n on ! occlusal surface1 z 9 ,m#a & ,m#b1 b lat]al inflection horizontally %all[ r ?an deep z 9 entopty*9es4 ,specim5 7,no4 ,p #bfbhd ,,fmnh7 report$ z ,dikkomys mat!wi by ,galbrea? 7#aidh3caf7 is ref]able to ! rec5tly describ$ species ,dikkomys woodi ,black1 #aifa4 ,specim5s exam9$4--,"o1 no4 ,p #bfbhd1 ,field ,mus4 ,nat4 ,hi/41 f upp] ,rosebud1 ,%annon ,co41 ,s\? ,dakota4 ,ref]r$ species4--two3 ,dikkomys mat!wi ,wood1 #aicf4 ,am]4 ,mus4 ,novit41 #hff3bf1 ,july4 ,type f e>ly ,arik>eean ,l[] ,h>rison deposits 7e>ly ,mioc5e7 ne> ,agate1 ,si\x ,c\nty1 ,nebraska4 ,dikkomys woodi ,black1 #aifa4 ,po/illa1 ,yale ,peabody ,museum1 #dh3ac1 ,janu>y #af4 ,type f ,deep ,riv] ,=mation1 late ,hem+=dian 7middle ,mioc5e71 ,meagh] ,c\nty1 ,montana2 also kn[n f ,upp] ,rosebud deposits 7middle ,mioc5e7 ne> ,w\nd$ ,knee1 ,%annon ,c\nty1 ,s\? ,dakota4 ,g5us ,pliosaccomys ,wilson #aicf4 ,pliosaccomys ,wilson1 ,c>negie ,in/4 ,wa%+ton ,publ41 #dgc3bj1 ,may #ba4 ,type4--,pliosaccomys dubius ,wilson1 #aicf1 f ,smi?s ,valley local fauna 9 ,lyon ,c\nty1 ,nevada4 ,*ronologic range4--,e>ly ,plioc5e1 late ,cl>5donian 7,wolf ,creek local fauna1 ,s\? ,dakota1 & ,nettle ,spr+s local fauna1 ,cali=nia7 to ,middle ,plioc5e1 middle "p ( ,hemphillian 7,smi?s ,valley local fauna1 ,nevada1 & ,mc,kay ,res]voir & ,otis ,bas9 local faunas1 ,oregon74 ,description4--,size small 7alveol> l5g? ( m&ibul> too?-r[ measur+ #f4j 9 holotype71 ab\t z 9 ,?omomys monticola2 upp] incisor relatively broad & flat1 hav+ ant]ior face smoo?1 )\t trace ( groov+2 cr[ns ( *eek tee? ( m$ium height & root$2 enamel inve/m5t cont9u\s & un9t]rupt$ 9 all /ages ( we>2 premol>s p]man5tly1 biprismatic2 ,p#d hav+ ant]ior prism subtriangul> & decid$ly small] t sub-cresc5tic po/]ior prism1 & jo9$ ne> c5t]s by n>r[1 obliquely ori5t$ i/hmus2 p#d hav+ ant]ior prism subovate1 po/]ior prism /rongly compress$ ant]opo/]iorly1 & jo9$ at mid-po9ts by relatively broad & /raight i/hmus2 fir/ & second mol>s1 bo? above & bel[1 monoprismatic 9 f9al 78adult7 /age ( we>1 d]iv$ ontog5etically f primitive bilophate patt]n by coalesc5ce ( two columns into "o2 ,m#a & ,m#b mirror images ( m#a & m#b 9 pre-f9al /ages ( we>1 two columns fir/ unit+ at edge ( protom]es =m+ ,u-patt]n1 & primitive ,h-patt]n nev] develop+ 9 ei!r s]ies 7= detail$ description ( /ages ( we>1 see acc\nt ( phylog5y1 p4 #edf72 m#c 7,m#c unkn[n1 b probably ) same =m z 9 ,geomy9i1 see p4 #eeb7 p]si/5tly biprismatic1 two columns jo9$ by relatively broad i/hmus at c5t]s1 consequ5tly1 =m+ ,h-patt]n ( primitive ance/ors2 ro/rum heavy & broad z 9 mod]n geomyids2 palate n>r[ & /rongly ribb$2 m&ible /\t2 masset]ic ridge & fossa well develop$2 basitemporal fossa abs5t4 ,specim5s exam9$4--,six1 nos4 #agif 7holotype7--#agii1 #ahjd & #ahjf 7,,cit7 n[ 9 ! ,los ,angeles ,c\nty ,museum1 all f ,smi?s ,valley local fauna1 ,middle ,plioc5e1 ,nevada4 ,ref]r$ species4--two3 99,pliosaccomys dubius ,wilson1 #aicf4 ,c>negie ,in/4 ,wa%+ton ,publ41 #gdc3bj1 ,may #ba4 ,kn[n f e>ly & middle ,plioc5e faunas includ+ ,wolf ,creek local fauna 7late ,cl>5donian71 ,%annon ,c\nty1 ,s\? ,dakota2 ,mc,kay ,res]voir local fauna & ,otis ,bas9 local fauna 7,hemphillian71 ,oregon2 type f ,smi?s ,valley local fauna 7probably middle ,hemphillian71 ,lyon ,c\nty1 ,nevada4 99,pliosaccomys wilsoni ,james1 #aifc4 ,univ4 ,cali=nia ,publ4 ,geol4 ,sci41 #de3aja1 ,june #bf4 ,type f ,nettle ,spr+s local fauna ( late ,cl>5donian 7e>ly ,plioc5e71 ,v5tura ,c\nty1 ,cali=nia4 ,tribe ,,?omomy9i1 new tribe ,type4--,?omomys ,wi$-,neuwi$1 #ahci4 ,*ronologic & geographic range4--,kn[n f late ,plioc5e 7e>ly ,blancan7 to ,rec5t4 ,kn[n prim>ily f we/]n ,nor? ,am]ica f s\!rn ,canada s\? to ,c5tral ,mxico 9 ,plioc5e1 ,plei/oc5e & ,rec5t & 9 middle & late ,plei/oc5e ( ,m>yl& & ,florida4 ,diagnosis4--,size small to m$ium 7basil> l5g? exclusive ( ,t4 bulbivorus1 measur+ f approximately #bd to #de1 includ+ bo? males & females72 upp] incisors )\t groov+1 except+ f9e1 indi/9ct sulcus r>ely ne> inn] m>g9 7groov+ m common 9 ,t4 monticola ?an 9 o!r ,rec5t species72 cr[ns ( *eek tee? high1 root$ & ev]-gr[+2 all mol>s1 includ+ ,m#c1 monoprismatic & ant]opo/]iorly compress$1 sometimes 7especially 9 subadults7 hav+ slight inflection on labial side 9 upp] tee? & l+ual side 9 l[] tee?2 mol>s bicolumn> 9 pre-f9al /ages ( we> 7se5 9 juv5al tee? only71 patt]ns ( we> 9 bo? upp] & l[] mol>s resembl+ ^? ( ,pliosaccomys1 except t cr[ns ( m#c & ,m#c unite into s+le column 9 f9al /ages ( we>2 enamel patt]n int]rupt$ 9 all *eek tee?1 loss occurr+ only at sides ( ea* column2 transv]se enamel blade completely cov]+ po/]ior face ( bo? ,p#d & p#d2 all upp] & l[] mol>s ) two transv]se enamel blades1 "o on ant]ior surface & "o on po/]ior surface1 ( ea* too?1 includ+ ,m#c2 small ?ird plate sometimes p]si/5t on broad side ( too?1 labial side 9 upp] mol>s & l+ual side 9 l[] mol>s 7,t4 bulbivorus72 skull g5]aliz$1 nei!r unusually n>r[ & deep or broad & flat2 usually )\t m>k$ cre/+ or rugosity2 masset]ic ridge well develop$ & massive2 basitemporal fossa abs5t1 sometimes %all[ depression =m+ 9 ,t4 t[ns5dii2 pelage s(t1 nev] h>% or hispid1 cov]+ body ) ?ick coat ( hair2 =efoot exceptionally small = fossorial mammal1 claws n especially long2 body =m rem>kably fossorial4 ,! tribe ,?omomy9i is monotypic1 includ+ only ! g5us ,?omomys4 ,g5us ,?omomys ,wi$-,neuwi$ #ahci4 ,?omomys ,wi$-,neuwi$1 ,nova ,acta ,phys4 ,m$4 ,acad4 ,caes>4 ,leop4-,c>ol41 #ai7a73cgg4 #ahcf4 ,oryctomys ,eyd\x & ,g]vais 79 "p71 ,mag4 de ,zool41 #f3bj1 pl4 #ba4 ,type3 ,oryctomys 7,saccophorus7 bottae1 f coa/ ( ,cali=nia1 probably ne> ,mont]ey4 #aijc4 ,megascapheus ,elliot1 ,field ,columb4 ,mus41 ,publ4 #gf1 ,zool4 ,s]41 #c7aa73aij1 ,july #be4 ,type3 ,diplo/oma bulbivorum ,ri*>dson1 f ,columbia ,riv]1 probably ne> ,portl&1 ,ore4 #aicc4 ,pleiso?omomys ,gidley & ,gaz91 ,j\r4 ,mamm4 #ad3ced4 ,type3 ,pleiso?omomys potomac5sis ,gidley & ,gaz91 f ,plei/oc5e1 ,cumb]l& ,cave local fauna1 ,allegany ,c\nty1 ,m>yl&4 ,*ronologic range4--,kn[n f late ,plioc5e to ,rec5t4 ,description4--,same z t giv5 = ! tribe ,?omomy9i above4 ,discussion4--,features *>act]iz+ ,?omomys & ! tribe ,?omomy9i are m advanc$ ?an ^? *>act]iz+ ! tribe ,dikkomy9i4 ,also1 ! ,?omomy9i reta9 m ( ! primitive features ( ! ,geomy9ae ?an d ! m specializ$ tribe ,geomy9i4 ,specializations are few1 b include ! ?ird mol> be+ a s+le column bo? above & bel[1 enamel plates1 & a masset]ic ridge4 ,key to ! ,subg5]a ( ,?omomys ,a ,mol>s sub-cresc5t or ovate 9 cross-section1 n becom+ abruptly n>r[] at "o end ( too?4 ,subg5us ,pleiso?omomys p4 #eai ,a ,mol>s pe>-%ap$1 n sub-cresc5t or ovate1 9 cross-section1 cr[n becom+ abruptly n>r[ at "o end ( too?4 ,subg5us ,?omomys p4 #ebj ,subg5us ,pleiso?omomys ,gidley & ,gaz9 #aicc4 ,pleiso?omomys ,gidley & ,gaz91 ,j\r4 ,mamm41 #ad3ced1 ,novemb] #ac4 ,type4--,pleiso?omomys potomac5sis ,gidley & ,gaz91 #aicc4 ,*ronologic range4--,late ,plioc5e 7,hag]man local fauna1 ,idaho7 to late ,plei/oc5e4 ,! late/ records are f ! fauna ( ,sab]-too? ,cave1 ,florida1 a late ,plei/oc5e assemblage t probably 0 deposit$ 9 ! ,sangamon4 ,! middle & late ,plei/oc5e records are f ! ea/]n ,unit$ ,/ates1 sugge/+ t ! subg5us ,pleiso?omomys 0 re/rict$ to t region :ile ! subg5us ,?omomys occupi$ ! we/]n ,unit$ ,/ates & p>ts ( ,canada & ,mxico z x does today4 ,description & ,comp>ison4--,sep>at$ f subg5us ,?omomys only on basis ( sub-cresc5tic %ap$ mol>s 7only jaw fragm5ts & isolat$ tee? kn[n71 seem+ly a primitive feature ( ! g5us4 ,?is d5tal /ructure cont9u$ into ! late ,plei/oc5e2 none ( ! ,rec5t species expresses ?is feature ( ! mol>s1 al?\gh ! mol>s ( ,?omomys vetus ( ! late ,plei/oc5e 7,wiscons9 deposits71 ref]r$ to ! subg5us ,?omomys on ! basis ( its alleg$ relation%ip to ,?omomys t[ns5dii 7see ,davis1 #aicg3aef-aeh71 are less di/9ctly pe>-%ap$1 & are m sub-cresc5tic1 ?an 9 any o!r kn[n species ( ! subg5us ,?omomys4 ,pleiso?omomys ,gidley & ,gaz9 7loc4 cit47 0 propos$ z a g5us b is "h consid]$ z ( no m ?an subg5]ic wor?1 & is recogniz$ because ( ! app>5t con/ancy ( ! sub-cresc5tic mol>s 9 ! e>li] memb]s ( ! g5us & 9 ^? populations ( ,?omomys occurr+ 9 ,plei/oc5e times 9 ! ea/]n ,unit$ ,/ates4 ,ref]r$ species4--,?ree 7all ext9ct73 99,?omomys gidleyi ,wilson1 #aicc4 ,c>negie ,in/4 ,wa%+ton ,publ4 #ddj3abb1 ,decemb]4 ,type f ,hag]man b$s1 late ,plioc5e1 ,idaho4 99,?omomys potomac5sis ,gidley & ,gaz91 #aicc4 ,j\r4 ,mamm41 #ad3ced1 ,novemb] #ac4 ,type f ,cumb]l& ,cave1 middle & late ,plei/oc5e1 ,m>yl&4 99,?omomys ori5talis ,simpson1 #aibh4 ,am]4 ,mus4 ,novit41 #cbh3f1 ,octob] #bf4 ,type f ,sab]-too? ,cave1 late ,plei/oc5e1 ,florida4 ,subg5us ,?omomys ,wi$-,neuwi$ #ahci4 ,?omomys ,wi$-,neuwi$1 ,nova ,acta ,phys4-,m$4 ,acad4 ,caes>4 ,leop4 ,c>ol41 #ai7a73cgg4 #aijc4 ,megascapheus ,elliot1 ,field ,columb4 ,mus41 ,publ4 #gf1 ,zool4 ,s]41 #c 7#aa73aij1 ,july #be4 ,type3 ,diplo/oma bulbivorum ,ri*>dson1 f ,columbia ,riv]1 probably ne> ,portl&1 ,oregon4 ,type4--,?omomys rufesc5s ,wi$-,neuwi$1 #ahci4 ,*ronologic range4--,e>ly ,plei/oc5e 7,broadwat]-,lisco local fauna1 ,nebraska7 to ,rec5t4 ,num]\s records1 mo/ly isolat$ tee?1 f ne>ly all /ratigraphic levels ( ! ,plei/oc5e 7= details1 see acc\nt ( fossil record74 ,description4--,mol>s pe>-%ap$ 9 cross-section1 becom+ abruptly n>r[ at "o end ( ! too?4 ,! tee? ( ! late ,plei/oc5e species ,?omomys vetus are less di/9ctly pe>-%ap$ ?an o!r ref]r$ species 7see rem>ks 9 ! description ( ! subg5us ,pleiso?omomys74 ,ess5tially on ! basis ( its significantly l>g] size & details ( ! skull1 ,elliott 7#aijc3aij7 propos$ subg5]ic recognition ( ,?omomys bulbivorus & describ$ ! subg5us ,megascapheus to include x4 ,also ! mol>s ( ,?omomys bulbivorus usually h a small enamel plate1 bo? above & bel[1 bord]+ ! p]si/5t inflection on ! protom]e end ( ! too?2 ea* lat]al plate is isolat$ f ! transv]se plates on ! ant]ior & po/]ior walls ( ! too?4 ,9 my op9ion ^! features d n w>rant subg5]ic recognition2 h[ev]1 ^! *>act]s d di/9ctly sep>ate ,?omomys bulbivorus f o!r gr\ps ( species1 & ! "* ( ! mol>s sugge/s ret5tion ( a primitive trait4 ,!re=e1 ,i propose t ! unique /ructure ( ?is species be recogniz$ by sett+ x ap>t 9 ! bulbivorus species-gr\p4 ,ref]r$ species4--,t5 species1 ?ree ext9ct1 plac$ 9 ?ree species-gr\ps 7! num]\s subspecies ( ?is g5us are li/$ 9 ,mill] & ,kellogg1 #aiee3bgf-ccb1 & ,hall & ,kelson1 #aiei3dab-ddg74 bulbivorus species-gr\p ,?omomys bulbivorus 7,ri*>dson1 #ahbi74 ,fauna ,boreali-,am]icana1 #a3bjf4 ,type f ,columbia ,riv]1 probably ne> ,portl&1 ,oregon4 umbr9us species-gr\p 99,?omomys scudd]i ,hay1 #aiba4 ,proc4 ,u4 ,s4 ,nat4 ,mus41 #di3fad4 ,type f ,fossil ,lake b$s1 late ,plei/oc5e1 ,oregon4 ,?omomys umbr9us 7,ri*>dson1 #ahbi74 ,fauna ,boreali-,am]icana1 #a3bjb4 ,type f s\!rn ,mxico1 probably ne> ,boca de ,monte1 ,v]acruz4 ,?omomys bottae 7,eyd\x & ,g]vais1 #ahcf74 ,mag4 de ,zool41 ,p>is1 #f3bc4 ,type f coa/ ( ,cali=nia1 probably ne> ,mont]ey4 99,?omomys vetus ,davis1 #aicg4 ,j\r4 ,mamm41 #ah3aef1 ,may #ab4 ,type f ,fossil ,lake b$s1 late ,plei/oc5e1 ,oregon4 ,?omomys t[ns5dii 7,ba*man1 #ahci74 ,j\r4 ,acad4 ,nat4 ,sci4 ,philadelphia1 #h3aje4 ,type probably f ne> ,nampa1 ,canyon ,co41 ,idaho 7errone\sly giv5 z ,columbia ,riv]74 talpoides species-gr\p 99,?omomys microdon ,s9clair1 #aije4 ,bull4 ,dept4 ,geol4 ,univ4 ,cali=nia1 #d3ade-afa4 ,type f ,pott] ,creek ,cave1 late ,plei/oc5e1 ,cali=nia4 ,?omomys monticola ,j4 ,a4 ,all51 #ahic4 ,bull4 ,am]4 ,mus4 ,nat4 ,hi/41 #e3dh1 ,april #bh4 ,type f ,mt4 ,tallac1 #gejj ft41 ,el ,dorado ,co41 ,cali=nia4 ,?omomys talpoides 7,ri*>dson1 #ahbh74 ,zool4 ,j\r41 #c3eah4 ,type locality fix$ at ne> ,=t ,c>lton 7,c>lton ,h\se71 ,saskat*ewan ,riv]1 ,saskat*ewan1 ,canada4 ,?omomys mazama ,m]riam1 #ahig4 ,proc4 ,biol4 ,soc4 ,wa%+ton1 #aa3bad1 ,july #ae4 ,type f ,anna ,creek1 #fjjj ft41 ne> ,crat] ,lake1 ,mt4 ,mazama1 ,klama? ,co41 ,wa%+ton4 ,tribe ,,geomy9i1 new tribe ,g5otype4--,geomys ,raf9esque1 #ahag4 ,*ronologic & geographic range4--,kn[n f late middle ,plioc5e deposits to ,rec5t4 ,! range ( liv+ memb]s ext5ds f extreme s\!rn ,manitoba & ! s\!a/]n ,unit$ ,/ates s\? to s\!rn ,panam1 & probably nor!rn ,colombia1 ,s\? ,am]ica4 ,diagnosis4--,size small to l>ge 7condylobasal l5g? ( skull #cc4j to #gc4j 9 adults1 includ+ bo? sexes72 sexual dimorphism m>k$1 sometimes /rongly1 females be+ small] ?an males1 especially 9 cranial dim5sions2 upp] incisors inv>iably groov$1 numb] & position ( grooves v>y+ accord+ to g5us2 *eek tee? high-cr[n$ & ev]-gr[+1 except 9 "o primitive g5us 7,pliogeomys72 all ?ree l[] mol>s & ,m#a & ,m#b monoprismatic1 & elliptical 9 cross-section 9 f9al /ages ( we> 7tee? ( "y1 subadult1 & adult animals72 primitive biprismatic patt]ns 7z kn[n f ,rec5t specim5s7 occurr+ only 9 pre-f9al /ages ( we> 7tee? ( juv5iles only72 biprismatic patt]ns ( l[] mol>s z 9 ,dikkomys1 & upp] mol>s z 9 ,pliosaccomys 7= detail$ description ( ^! patt]ns1 see acc\nt beyond ( ! phylog5y ( ! ,geomy9ae72 m#c becom+ monoprismatic1 ant]opo/]iorly compress$ & elliptical 9 cross-section l m#a & m#b1 b ,m#c rema9+1 ) r>e exceptions 7see acc\nts ( ,geomys & ,pappogeomys beyond71 at lea/ p>tially biprismatic ?r\gh\t life1 hav+ "o or bo? lat]al inflections usually p]si/+ 7) exceptions7 & develop+ v>i\s occlusal %apes 7subtriangul>1 elongate1 obcordate1 suborbiculate1 or quadri=m7 b nev] elliptical4 ,enamel ( *eek tee? r$uc$ to int]rupt$ plates1 ) exception ( p#d 9 ,pliogeomys2 plate on po/]ior wall ( ,p#d v>iable1 occurr+ completely across po/]ior surface 9 primitive memb]s1 b progressively r$uc$ to l+ual side only or completely lo/ 9 mod]n g5]a 7see g5]ic acc\nts beyond = detail$ description72 bo? ant]ior & po/]ior plates usually reta9$ 9 ,m#a & ,m#b1 po/]ior plate sometimes r$uc$ to l+ual side or completely lo/ 7z 9 ,pappogeomys7 b ant]ior plate always completely reta9$2 ,m#c usually hav+ ?ree plates1 "o ant]ior & two lat]al2 po/]ior plate want+ 7sometimes l+ual plate mov$ to po/]ior position72 plates reta9$ completely across po/]ior walls ( all l[] *eek tee? ) no r$uction1 b ant]ior plates ( m#a-c always lack+1 except 9 primitive g5us ,pliogeomys 7only ,geomy9i hav+ bo? ant]ior & po/]ior enamel plates on l[] mol>s74 ,skull primitively g5]aliz$1 b becom+ specializ$ t[>ds ei!r doli*ocephaly 7,or?ogeomys7 or platycephaly 7,pappogeomys7 9 two mod]n g5]a2 skull highly specializ$ = fossorial life2 m&ible /\t & deep1 angul> process be+ high & div]g+ lat]ally at "r angles to ramus2 masset]ic ridge & fossa weakly develop$ 9 primitive memb]s1 becom+ well develop$ & massive 9 mod]n g5]a2 basitemporal fossa abs5t 9 primitive =ms 7,pliogeomys & e>ly memb]s ( ,zygogeomys72 pelage usually s(t1 b h>% & hispid 9 "s g5]a2 =efeet broad & massive1 claws long & /\t = digg+2 body =m rem>kably fossorial4 ,! tribe ,geomy9i includes ! mo/ highly specializ$ memb]s ( ! subfamily ,geomy9ae4 ,key to ! ,g5]a ( ! ,tribe ,geomy9i ,a ,*eek tee? root$2 p#d ) un9t]rupt$ enamel loop2 enamel plates on bo? ant]ior & po/]ior walls ( m#a & m#b2 masset]ic ridge weakly develop$1 l[1 n massive4 ,g5us ,pliogeomys p4 #ebb ,a ,*eek tee? rootless1 ev]-gr[+2 p#d ) enamel inve/m5t int]rupt$ at ends ( columns1 consequ5tly1 =m+ f\r islot$ plates2 enamel plate reta9$ only on po/]ior wall ( m#a & m#b1 ant]ior wall )\t trace ( enamel 7except r>ely 9 pre-f9al /age ( we> 9 ,geomys tob95sis ( middle ,plei/oc5e72 masset]ic cre/ /rongly develop$ & massive4 ,b ,enamel plate on po/]ior wall ( ,p#d1 b usually re/rict$ to l+ual end ( too? 7usually abs5t 9 subg5us ,or?ogeomys ( g5us ,or?ogeomys72 ,m#c conspicu\sly bicolumn>1 long] ?an wide ow+ to elongation ( po/]ior loph4 ,c ,upp] incisor bisulcate2 skull g5]aliz$2 ro/rum relatively n>r[2 l5g? ( labial enamel plate ( ,m#c decid$ly less ?an l5g? ( l+ual plate2 pelage s(t & ?ick4 ,g5us ,zygogeomys p4 #ebc ,c ,upp] incisor unisulcate2 skull /rongly doli*ocephalic2 ro/rum rem>kably broad & massive2 l5g? ( l+ual plate ( ,m#c approximately equal to1 or great] ?an1 l5g? ( labial plate2 pelage h>%1 (t5 hispid & scant4 ,g5us ,or?ogeomys p4 #ebh ,b ,po/]ior wall ( ,p#d )\t trace ( enamel2 ,m#c n /rongly bicolumn>1 hav+ %all[ re-entrant fold on labial side1 & cr[n no long] ?an wide ow+ to %ortness ( po/]ior loph4 ,d ,upp] incisor bisulcate2 skull g5]aliz$2 bo? ant]ior & po/]ior walls ( ,m#a & ,m#b hav+ complete enamel plates4 ,g5us ,geomys p4 #ebe ,d ,upp] incisor unisulcate2 skull g5]aliz$ or t5d+ t[>ds platycephaly2 enamel plate on po/]ior wall ( ,m#a usually r$uc$ to l+ual side or abs5t 7complete only 9 "o species1 ,pappogeomys bull]i72 enamel plate on po/]ior wall ( ,m#b also abs5t 9 advanc$ species 7subg5us ,cratogeomys74 ,g5us ,pappogeomys p4 #ecb ,g5us ,pliogeomys ,hibb>d #aied4 ,pliogeomys ,hibb>d1 ,mi*igan ,acad4 ,sci41 ,arts & ,lett]s1 #ci3cec4 ,g5otype4--,pliogeomys buisi ,hibb>d1 #aied1 f ,buis ,ran* local fauna 7middle ,plioc5e71 ,beav] ,c\nty1 ,oklahoma4 ,*ronologic range4--,late/ ,middle ,plioc5e1 kn[n only f ! highe/ "p ( ! ,hemphillian mammalian fauna 7,buis ,ran* local fauna1 ,oklahoma74 ,pr(essor ,hibb>d in=ms me 7p]sonal communication7 t he f\nd ! type1 a "r ramus1 ly+ on ! surface ne> ! base ( ! fossil b$s4 ,! isolat$ tee? ( small geomyids f ! ,saw ,rock ,canyon local fauna 7see ,hibb>d1 #aiec3cib7 may also be ref]able to ?is g5us4 ,! ,saw ,rock ,canyon local fauna may also be middle ,plioc5e 9 age b is consid]$ to be f ! lat] "p ( ! late ,plioc5e1 &1 !re=e1 some:at y\ng] ?an ! ,buis ,ran* local fauna 7,hibb>d1 op4 cit43#cdb74 ,description & discussion4--,! size ( memb]s ( ?is small g5us ( ! ,geomy9ae is ab\t ! same z 9 small] adults ( ,geomys burs>ius4 ,accord+ to ,hibb>d 7op4 cit43#cec71 ! holotype is small] ?an specim5s f ! ,rexroad local fauna ref]r$ to ,geomys qu9ni & l>g] ?an specim5s ref]r$ to ,zygogeomys cf4 m9or4 ,! *eek tee? are root$1 & ! cr[ns are z high z ^? ( liv+ geomyids4 ,! upp] incisor is bisulcate1 & ! inn] groove is f9e & indi/9ct 9 places4 ,( ! mol>i=m d5tition only ! l[] premol> & fir/ two l[] mol>s are kn[n4 ,! enamel inve/m5t ( p#d is complete1 & w\ld n be subject to int]ruption at any /age ( we>2 ! two prisms are jo9$ at _! mid-po9ts1 & ! i/hmus ( d5t9e is relatively broad 7z 9 ,pliosaccomys7 :5 comp>$ ) mod]n pocket goph]s ( ?is tribe4 ,also1 ! re-entrant folds1 r ?an hav+ p>allel sides1 div]ge broadly to ! sides4 ,! div]g5ce is especially noticeable 9 ! labial fold4 ,! l[] decidu\s premol> w\ld h =m$ ess5tially ! same enamel patt]n ) we> z obs]v$ 9 ,n]t]ogeomys ,zygogeomys cf4 m9or 7see ,hibb>d1 #aied3;fig4 #e1 ,a & ,b7 & ,pliosaccomys dubius 7see ,wilson1 #aicf2 pl4 #a1 fig4 #a74 ,ea* mol> is a s+le column 9 ! f9al /ages ( we>2 pre-f9al /ages are unkn[n4 ,ant]ior & po/]ior enamel plates are pres5t on m#a & m#b 7m#c has n be5 recov]$74 ,! d5t9e tracts ( m#a are expos$ ov] a relatively wide surface2 !re=e1 ! enamel plates are di/9ctly sep>at$4 ,! tracts ( d5t9e ( m#b are mu* n>r[] ?an 9 m#a & ! enamel plates are b>ely sep>at$ at ! ant]olat]al m>g9 ( ! too?4 ,possibly ! enamel b& ( m#b 0 cont9u\s 9 an e>li] /age ( we>4 ,! m&ible is /\t & its g5]al con/ruction n unlike t 9 mod]n geomy9es4 ,! capsule at ! base ( ! angul> process t receives ! t]m9al end ( ! l[] incisor is well develop$4 ,! base ( ! angul> processes is pres]v$1 & sugge/s t ! process 0 %ort & decid$ly small] ?an 9 liv+ examples ( ! tribe4 ,! masset]ic ridge is di/9ct b weakly develop$1 & n at all massive z 9 liv+ pocket goph]s4 ,! m5tal =am5 is imm$iately ant]ior1 & slightly v5tral1 to ! ant]ior ext5sion ( ! cre/4 ,! basitemporal fossa is abs5t z su*1 b its position is m>k$ by a slight depression4 ,specim5s exam9$4--,two rami2 nos4 #biadg 7holotype7 & #ccddf2 sev]al isolat$ tee? #cjaid & #cjaie1 includ+ an upp] incisor & a dp#d 7decidu\s l[] premol>71 all f ,univ4 ,mi*igan ,mus4 ,paleo4 ,ref]r$ species4--,"o4 99,pliogeomys buisi ,hibb>d1 #aied4 ,pap]s ,mi*igan ,acad4 ,sci41 ,arts1 & ,lett]s1 #ci3cec4 ,type f ,buis local fauna1 late/ middle ,plioc5e1 ,beav] ,c\nty1 ,oklahoma4 ,g5us ,zygogeomys ,m]riam #ahie4 ,zygogeomys ,m]riam1 ,n4 ,am]4 ,fauna1 #h3aie1 ,janu>y #ca4 #aidb4 ,n]t]ogeomys ,gaz91 ,proc4 ,u4 ,s4 ,nat4 ,mus41 #ib3ejg 7type1 ,geomys p]similis ,hay1 #aibg74 ,type4--,zygogeomys tri*opus ,m]riam1 #ahie1 f ,nahuatz51 ,mi*oacn4 ,*ronologic range4--,late ,plioc5e 7,b5son & ,curtis ,ran* local faunas1 ,arizona1 & 8,rexroad ,=mation1 ,kansas7 to ,rec5t4 ,description & discussion4--,! size is small to m$ium = ! subfamily ,geomy9ae4 ,?is g5us is di/+ui%$ pr9cipally by ! ret5tion ( primitive features4 ,9 ! liv+ species1 ! skull is g5]aliz$1 r ?an specializ$ t[>d ei!r extreme doli*ocephaly or platycephaly4 ,! angul> process is %ort1 b>ely exce$+ ! lat]al ext5sions ( ! ma/oid process ( ! squamosal4 ,! ro/rum is rem>kably n>r[ 9 relation to its l5g?4 ,! jugal is r$uc$ & displac$ v5trally1 caus+ ! maxill>y arm ( ! zygomata to articulate ) ! squamosal arm ( ! zygomata along ! dorsal bord] ( ! zygomatic ar* 7a feature obs]v$ also 9 ,or?ogeomys *]riei co/>ic5sis74 ,! upp] incisor1 recov]$ 9 mat]ial f ! late ,plioc5e & middle ,plei/oc5e1 is bisulcate z 9 ! g5us ,geomys & ! primitive g5us ,pliogeomys4 ,! enamel plate across ! po/]ior wall ( ,p#d is ei!r complete 7late ,plioc5e to late ,plei/oc5e7 or re/rict$ to ! l+ual half ( ! too? 7always re/rict$ 9 liv+ species74 ,! ,plioc5e specim5s ( ! ,rexroad local fauna ref]r$ to ,n]t]ogeomys cf4 m9or by ,hibb>d 7#aiej3ach-aci7 are exceptional4 ,9 ^! specim5s ! l5g? & position ( ! po/]ior enamel plate is v>iable2 h[ev]1 all b "o specim5 _h p]si/ant enamel4 ,evid5tly1 9 approximately #dc p] c5t ( ! specim5s1 a complete enamel blade 0 pres5t 7see ,paulson1 #aifa3aci71 & 9 ! o!rs 7except ! "o )\t any enamel7 ! plate 0 re/rict$ to a small area ( ! v5tral surface1 usually on ! l+ual side ( ! loph4 ,hibb>d sugge/$ t ! decrease 9 size ( ! plate1 & its re/riction to ! l+ual side1 may be a function ( age4 ,h5ce1 mo/ adults w\ld be *>act]iz$ by ! r$uc$ po/]ior plate on ! upp] premol>4 ,al?\gh age may be ! important factor1 intragr\p v>iation _c be rul$ out4 ,x is ( int]e/ to note t 9 all specim5s f ! ,b5son 7type s]ies ( ,p4 m9or7 & ,curtis ,ran* local faunas1 ! =m] ( late ,plioc5e age & ! latt] ( middle ,plei/oc5e age1 ! enamel plates are complete on ! po/]ior face ( ! upp] premol>4 ,z m5tion$ be=e1 ! specim5s f ,kansas may actually repres5t ! transitional /ages ( ! e>ly evolution ( ,geomys 9 :i* ! po/]ior plate ( ,p#d is entirely lo/4 ,! enamel patt]n ( p#d is l t 9 o!r memb]s ( ! tribe 7except+ ! g5us ,pliogeomys74 ,! re-entrant angles ( ,p#d & p#d are widely op5 7obtuse7 9 ! examples recov]$ f late ,plioc5e & middle ,plei/oc5e deposits1 repres5t+ ret5tion ( a trait t is primitive 9 ! ,geomy9i 7see acc\nt ( phylog5y74 ,m#a & ,m#b are elliptical 9 cross-section & ea* has an enamel plate on bo? ! ant]ior & po/]ior surface4 ,9 ! liv+ species 7,z4 tri*opus71 ! po/]ior enamel plate fails to rea* ! labial m>g9 ( ! too? & is re/rict$ to ! l+ual two-?irds ( ! po/]ior surface2 h[ev]1 ! enamel plates are complete 9 ! late ,plioc5e species 7,z4 m9or7 & ! middle ,plei/oc5e species 7,z4 p]similis71 be+ only slightly sep>at$ f ! ant]ior plate by n>r[ tracts ( d5t9e on ! ends ( ! too?4 ,m#c is p>tly biprismatic 9 ! liv+ species1 ! two incompletely divid$ lophs be+ sep>at$ by a di/9ct out] sulcus4 ,! po/]ior loph is elongat$ & =ms a conspicu\s heel p>allel+ ! evolution ( ?is trait 9 ! g5us ,or?ogeomys2 !re=e1 ! cr[n is long] ?an wide4 ,! po/]ior "p ( ! too? is protect$ by two lat]al enamel plates2 ( ! two1 ! l+ual plate is especially long & ext5ds to ! end ( ! heel4 ,m#c has n be5 recov]$ 9 ! ,plioc5e species1 b 9 ! middle ,plei/oc5e species 7,z4 p]similis7 ,m#c is subtriangul>1 no long] ?an wide1 & ! lat]al inflections are weakly develop$4 ,! tr5d t[>ds elongation ( ,m#c evid5tly occurr$ 9 late ,plei/oc5e evolution ( ! g5us4 ,all ?ree ( ! inf]ior mol>s are elliptical1 & only ! po/]ior enamel plate is pres5t 7z 9 all o!r g5]a ( ! tribe except ,pliogeomys74 ,! masset]ic ridge ( ! m&ible is well develop$4 ,9 ! late ,plioc5e species ,z4 p]similis & ,z4 m9or ! m5tal =am5 is directly b5ea? ! ant]ior ext5sion ( ! masset]ic ridge1 b 9 ! liv+ species1 ,z4 tri*opus1 ! =am5 lies well ant]ior to ! ridge4 ,! basitemporal fossa 9 ! liv+ species is well develop$ & deep2 9 ! ,plioc5e species x is usually di/9ct b %all[ 7late ,plioc5e specim5s ( ,z4 m9or74 ,ref]r$ species4--,?ree 7two ext9ct & "o liv+2 ! la/ has two subspecies73 99,zygogeomys m9or 7,gidley71 #aibb4 ,u4 ,s4 ,geol4 ,surv4 ,pr(4 ,pap]1 #aca3abc1 ,decemb] #bf4 ,type f ,b5son local fauna 7late ,plioc5e71 ,co*ise ,c\nty1 ,arizona2 also kn[n f ! ,rexroad local fauna1 ,meade ,c\nty1 ,kansas4 99,zygogeomys p]similis ,hay1 #aibg4 ,c>negie ,in/4 ,wa%+ton ,publ41 #acf4 ,orig9ally describ$ by ,gidley1 #aibb 7,u4 ,s4 ,geol4 ,surv4 ,pr(4 ,pap]s1 #aca3abc1 ,decemb] #bf7 z ,geomys p>vid5s :i* 0 preoccupi$ by ,g4 p>vid5s ,br[n1 #aijh4 ,type f ,curtis ,ran* local fauna 7middle ,plei/oc5e71 ,co*ise ,c\nty1 ,arizona4 ,zygogeomys tri*opus tri*opus ,m]riam1 #ahie4 ,n4 ,am]4 ,fauna1 #h3aif1 ,janu>y #ca4 ,type f ,nahuatz51 ,mi*oacn4 ,zygogeomys tri*opus t>asc5sis ,goldman1 #aich4 ,proc4 ,biol4 ,soc4 ,wa%+ton1 #ea3baa1 ,decemb] #bc4 ,type f #f mi4 ,,se ,ptzcu>o1 #h1jjj ft41 ,mi*oacn4 ,g5us ,geomys ,raf9esque #ahag4 ,geomys ,raf9esque1 ,am]4 ,mon?ly ,mag41 #b7a73de1 ,novemb]4 #ahag4 ,diplo/oma ,raf9esque1 ,am]4 ,mon?ly ,mag41 #b7a73dd-de1 ,novemb]4 ,includ$ species3 ,diplo/oma fusca ,raf9esque ,mus burs>ius ,%aw & ,diplo/oma alba ,raf9esque ,mus burs>ius ,%aw f ! ,miss\ri ,riv] region4 #ahbj4 ,saccophorus ,kuhl1 ,beitr4 ,zool4 und ,v]gl4 ,anat41 pp4 #fe1 #ff4 ,type3 ,mus burs>ius ,%aw1 f upp] ,mississippi ,valley4 #ahbc4 ,pseudo/oma ,say1 ,long's ,expd4 ,rocky ,mts41 ,i1 pp4 #djf4 ,type3 ,pseudo/oma burs>ia ,mus burs>ius ,%aw1 f upp] ,mississippi ,valley4 #ahbe4 ,ascomys ,li*t5/e91 ,abh4 ,k4 ,akad4 ,wiss4 ,b]l9 7#ahbb71 p4 #bj41 fig4 #b4 ,type3 ,ascomys canad5sis ,li*t5/e9 ,mus burs>ius ,say1 probably f upp] ,mississippi ,valley4 #aidd4 ,p>ageomys ,hibb>d1 ,bull4 ,geol4 ,soc4 ,am]41 #ee3gce1 ,june4 ,type3 ,p>ageomys tob95sis ,hibb>d1 f ,plei/oc5e1 ,cudahy 7,tob97 local fauna1 ,russell ,co41 ,kansas4 ,type4--,geomys p9etis ,raf9esque1 #ahag1 re/rict$ to ,screv5 ,c\nty1 ,georgia1 9 region ( ! p9es4 ,*ronologic range4--,late ,plioc5e faunas ( ,blancan age 7,rexroad1 ,kansas1 & ,s& ,draw1 ,nebraska1 local faunas7 to ,rec5t4 ,report$ f num]\s ,plei/oc5e deposits ( all /ratigraphic levels1 especially f ! ,great ,pla9s1 :]e common today4 ,description & discussion4--,pocket goph]s ( ?is g5us are m$ium-siz$ geomyids2 none is s small z ! av]age-siz$ ,?omomys4 ,! skull is g5]aliz$ & lacks ! doli*ocephalic & platycephalic specializations se5 9 ! g5]a ,or?ogeomys & ,pappogeomys1 respectively4 ,geomys closely resembles ,zygogeomys1 b reta9s few] ( ! primitive *>act]s ( ! ance/ral /ock4 ,at ! same "t1 ,geomys has sev]al specializations4 ,ev5 s1 a consid]able am\nt ( p>allelism is evid5t 9 ! phyletic tr5ds ( ! two g5]a4 ,! upp] incisor ( ,geomys is bisulcate z 9 ,pliogeomys & ,zygogeomys2 ! deep] grove is m$ial & ! %all[] grove lies ne> ! inn] bord] ( ! too?4 ,! premol>1 above & bel[1 is bicolumn>2 & two columns are jo9$ at _! mid-po9ts 7deep re-entrant angles sep>ate ! columns at ! sides74 ,a p]man5t enamel plate protects ! ant]ior face ( ! ant]ior loph1 & enamel b&s outl9e ea* ( ! re-entrant folds4 ,9 p#d a complete enamel plate cov]s ! po/]ior surface ( ! po/]ior loph4 ,all ( ! enamel b&s are int]rupt$ by tracts ( d5t9e1 except 9 ! initial /ages ( we> ( ! occlusal surface ( ! newly erupt$ too?4 ,= a %ort "t 9 liv+ ,geomys1 ! enamel b&s are cont9u\s z obs]v$ 9 juv5iles ( ,geomys burs>ius major 7,,ku #efbh1 #heca1 & #daedj74 ,b1 ! enamel cap is ?9 & ! d5t9e tracts1 :i* are high on ! sides ( ! too?1 are soon reveal$ by a m9imum ( we> on ! cr[n4 ,!re=e1 ! adult1 or f9al1 patt]n *>act]iz$ by int]rupt$ enamel plates em]ges e>ly 9 life & rema9s ?r\gh\t ! life ( ! individual4 ,evid5ce f fossil ,geomys1 especially f specim5s f e>ly & late ,plei/oc5e deposits1 sugge/s t ! f9al adult patt]n appe>s lat]1 ontog5etically1 ?an 9 ,rec5t specim5s4 ,"s ( ! fossil premol>s 9 initial /ages ( we> h cont9u\s & un9t]rupt$ b&s ( enamel4 ,geomys qu9ni ( ! late ,plioc5e & e>ly ,plei/oc5e has ! int]rupt$ patt]n se5 9 late ,plei/oc5e & ,rec5t ,geomys4 ,also1 9 late ,plioc5e & e>ly ,plei/oc5e species1 ! re-entrant folds div]ge lat]ally & =m op5 angles4 ,9 lat] taxa 7middle ,plei/oc5e to ,rec5t7 ! folds are compress$ & p>allel-sid$1 & ! op5 folds are f\nd only 9 ! e>ly /ages ( we>4 ,! po/]ior enamel plate ( ,p#d disappe>s 9 ! f9al /ages ( we> z ! int]rupt$ enamel patt]n is =m$4 ,9 ! late ,plei/oc5e & ,rec5t ,geomys1 ! loss ( ! po/]ior plate occurs e>ly 9 life1 usually 9 ! fir/ phases ( we> on ! occlusal surface ( ! newly erupt$ too?1 b 9 fossils ( ,geomys ( correspond+ ontog5etic age f ! e>ly & middle ,plei/oc5e1 ! po/]ior plate is reta9$ 9 "s individuals until a lat] phase ( we>1 !reby delay+ ! appe>ance ( ! f9al patt]n4 ,inde$1 9 five or few] p] c5t ( ! individuals 7see ,paulson1 #aifa3ach-aci2 & ,:ite & ,d[ns1 #aifa3ah7 a ve/ige ( enamel is reta9$ ?r\gh\t life or at lea/ until late 9 adul?ood4 ,9 ,geomys tob95sis1 = example1 a ?91 b transv]sely complete1 plate ( enamel occurs all ! way d[n to ! base ( ! loph 7,paulson1 loc4 cit47 & w\ld p]si/ ?r\gh\t life4 ,9 ,geomys g>banii1 a ve/ige on ! l+ual side ( ! po/]ior surface ( a fully adult specim5 0 not$ by ,:ite & ,d[ns 7loc4 cit474 ,ve/iges ( ! po/]ior plate occur less frequ5tly 9 liv+ geomyids4 ,paulson 7loc4 cit47 f\nd a po/]ior plate 9 "o ( #ge specim5s ( ,geomys burs>ius dut*]i4 ,a "y 7suture pres5t betwe5 exoccipitals & supraoccipital7 female ( ,geomys p9etis au/r9us 7,,ku #bcceh7 has a ve/ige ( ! po/]ior plate on ! l+ual side ( ! too? z ,:ite & ,d[ns 7loc4 cit47 obs]v$ 9 a specim5 ( ,geomys g>banii4 ,! enamel1 ,i suspect1 t5ds to be ?ick] on ! l+ual ?an on ! labial side ( ! loph & ext5ds f>!r d[n ! l+ual surface 9 "s individuals2 !re=e1 we> on ! occlusal surface erodes x d[n to ! d5t9e m rapidly on ! labial ?an on ! l+ual side4 ,! t5d5cy ( enamel to be reta9$ is a primitive feature4 ,a l[] mol> ( ,geomys is a s+le elliptical column1 & enamel is re/rict$ to ! po/]ior surface z 9 ,zygogeomys1 ,or?ogeomys1 & ,pappogeomys4 ,paulson 7loc4 cit47 f\nd a ?9 enamel plate on ! ant]ior surfaces ( ! l[] mol>s 9 ab\t five p] c5t ( ! individuals ( ,geomys tob95sis f ! ,cudahy local fauna 7middle ,plei/oc5e1 deposits ( ! late ,kansan glaciation74 ,an ant]ior plate is unkn[n 9 o!r memb]s ( ! tribe ,geomy9i1 except 9 ! primitive g5us ,pliogeomys ( ! middle ,plioc5e4 ,occurr5ce ( ! plate 9 ,geomys tob95sis is an atavi/ic trait4 ,primitive d5tal patt]ns occur occasionally 9 geomyids1 z po9t$ out above1 b ! frequ5cy ( occurr5ce 9 ,g4 tob95sis is high] ?an w\ld be expect$4 ,m#a & ,m#b1 l ! l[] mol>s1 are elliptical 9 cross-section4 ,complete enamel plates on ! ant]ior & po/]ior surfaces are sep>at$ by tracts ( d5t9e on ! sides ( ea* too?4 ,m#c is usually suborbicul> 7sometimes subtriangul>7 9 cross-section4 ,! too? is n especially elongat$ po/]iorly & usually has no def9ite heel2 !re=e1 x is n significantly long] ?an wide4 ,liv+ species ( ,geomys r>ely h a well def9$ out] re-entrant fold on ,m#c2 less ?an #aj p] c5t ( ! individuals 7& usually only "o side 9 ea* individual 9 :i* x occurs7 h x1 al?\gh a %all[ inconspicu\s groove occurs m frequ5tly4 ,! biprismatic mol> *>act]i/ic ( ! ance/ral morphotype is less (t5 f\nd 9 ,geomys ?an 9 any o!r liv+ memb] ( ! tribe ,geomy9i4 ,! out] re-entrant fold & biprismatic patt]n are m (t5 pres5t 9 ! ext9ct species ,geomys g>banii ( ! ,middle ,plei/oc5e ?an 9 o!r species4 ,less ?an #bd p] c5t ( ! ?ird upp] mol>s 9 ,geomys g>banii lack a tract ( ! re-entrant fold & m ?an #ch p] c5t h a well develop$ out] fold 7see ,:ite & ,d[ns1 #aifa3ac1 #ah74 ,! bicolumn> patt]n1 al?\gh incomplete1 w\ld be cle>ly evid5t 9 ^? tee? hav+ a well m>k$ re-entrant fold2 ! patt]n occurs less frequ5tly 9 ^? tee? ) no fold or only a slight "o4 ,m#c ( geomyids is n usually recov]$ &1 !re=e1 ! occlusal patt]n ( ,m#c is unkn[n 9 mo/ ext9ct k9ds ( ,geomys4 ,9 ,rec5t ,geomys ! fold is m common 9 ! ea/]n p9etis species-gr\p ?an 9 ! we/]n burs>ius species-gr\p4 ,! masset]ic ridge on ! out] side ( ! m&ible is well develop$ 9 all species ( ! g5us4 ,! position ( ! m5tal =am5 relative to ! ant]ior "p ( ! ridge v>ies ) individuals & accord+ to species4 ,! basitemporal fossa is always pres5t1 b is %all[] 9 ! late ,plioc5e & ,plei/oc5e species ?an 9 ,rec5t species4 ,! angul> process is %ort4 ,ref]r$ species4--,! twelve species1 five ( :i* are ext9ct1 are z foll[s3 qu9ni species-gr\p 99,geomys qu9ni ,mc,grew1 #aidd4 ,geol4 ,s]41 ,field ,mus4 ,nat4 ,hi/41 #i 7#edf73di1 ,janu>y #bj4 ,type f ,s& ,draw local fauna 7late ,plioc5e71 ,br[n ,c\nty1 ,nebraska2 also kn[n f ,broadwat]-,lisco local faunas 7e>ly ,plei/oc5e71 ,morrill & ,g>d5 c\nties1 ,nebraska1 ,de] ,p>k local fauna 7e>ly ,plei/oc5e71 ,meade ,c\nty1 ,kansas4 99,geomys pa5eburs>ius ,/ra91 #aiff4 ,bull4 ,texas ,memorial ,mus41 #aj3cf4 ,type f ,hudspe? local fauna 7e>ly ,plei/oc5e71 ,hudspe? ,c\nty1 ,texas4 99,geomys tob95sis ,hibb>d1 #aidd4 ,bull4 ,geol4 ,soc4 ,am]41 #ee3gcf4 ,type f ,tob9 local fauna 7middle ,plei/oc5e71 ,russell ,c\nty1 ,kansas2 also kn[n f ,cudahy local fauna 7middle ,plei/oc5e71 ,meade ,c\nty1 ,kansas4 99,geomys g>banii ,:ite & ,d[ns1 #aifa4 ,contrib4 ,sci41 ,los ,angeles ,co4 ,mus41 #db3a-cd1 ,june #cj4 ,type f ,vallecito ,creek local fauna 7middle ,plei/oc5e71 ,san ,diego ,c\nty1 ,cali=nia4 99,geomys bisulcatus ,m>%1 #ahga4 ,am]4 ,j\r4 ,sci41 #c3aba4 ,type f ,l\p ,riv] fossil b$s1 ne> ,camp ,?omas1 ,nebraska 7probably late ,plei/oc5e74 burs>ius species-gr\p 99,geomys p>vid5s ,br[n1 #aijh4 ,mem4 ,am]4 ,mus4 ,nat4 ,hi/41 #i3aid4 7,an ext9ct subspecies ( ,geomys burs>ius accord+ to ,:ite & ,d[ns1 #aifa3f74 ,type f ,con>d ,fissure local fauna 7late ,plei/oc5e71 nor!rn ,arkansas4 ,geomys burs>ius 7,%aw1 #ahjj74 ,trans4 ,l9n4 ,soc4 ,london1 #e3bbg4 ,type f some:]e 9 ,upp] ,mississippi ,valley1 ,nor? ,am]ica4 ,geomys ar5>ius ,m]riam1 #ahie4 ,n4 ,am]4 ,fauna1 #h3aci1 ,janu>y #ca4 ,type f ,el ,paso1 ,el ,paso ,c\nty1 ,texas4 ,geomys p]sonatus ,true1 #ahhi4 ,proc4 ,u4 ,s4 ,nat4 ,mus41 #aa3aei1 ,janu>y #e4 ,type f ,padre ,isl&1 ,cam]on ,c\nty1 ,texas4 p9etis species-gr\p ,geomys p9etis ,raf9esque1 #ahjf4 ,am]4 ,mon?ly ,mag41 #b 7#a73de1 ,novemb]4 ,type locality re/rict$ to ,screv5 ,c\nty1 ,georgia4 ,geomys colonus ,bangs1 #ahih4 ,proc4 ,bo/on ,soc4 ,nat4 ,hi/41 #bh3agh1 ,m>*4 ,type f ,arnot ,plantation1 ab\t #d mi4 ,w ,/4 ,m>ys1 ,camd5 ,c\nty1 ,georgia4 ,geomys cumb]l&ius ,bangs1 #ahih4 ,proc4 ,bo/on ,soc4 ,nat4 ,hi/41 #bh3ahj1 ,m>*4 ,type f ,/af=d ,place1 ,cumb]l& ,isl&1 ,camd5 ,c\nty1 ,georgia4 ,geomys fontanelus ,%]man1 #aidj4 ,j\r4 ,mamm41 #ba3cda1 ,augu/ #ac4 ,type f #g mi4 ,,nw ,savannah1 ,*a?am ,c\nty1 ,georgia4 ,g5us ,or?ogeomys ,m]riam #ahie4 ,or?ogeomys ,m]riam1 ,n4 ,am]4 ,fauna #h3agb1 ,janu>y #ca4 #ahie4 ,het]ogeomys ,m]riam1 ,n4 ,am]4 ,fauna #h3agi1 ,janu>y #ca 7type1 ,geomys hispidus ,le ,conte1 #ahfb74 #ahie4 ,macrogeomys ,m]riam1 ,n4 ,am]4 ,fauna #h3ahe1 ,janu>y #ca 7type1 ,geomys het]odus ,pet]s1 #ahfe74 ,type4--,geomys scalops ,?omas1 #ahid1 f ,tehuantepec1 ,oaxaca1 ,mxico4 ,*ronologic range4--,late ,plei/oc5e ,wiscons9 deposits 7,san ,josecito ,cave local fauna1 ,nuevo ,len1 ,mxico7 to ,rec5t4 ,description & discussion4--,species ( ?is g5us are ( m$ium to l>ge size4 ,! skull is /rongly doli*ocephalic 9 mo/ species2 ! po/]ior "p ( ! skull is especially n>r[4 ,! angul> processes are rem>kably %ort1 especially 9 relation to ! l5g? ( ! m&ible4 ,! nasals & ro/rum are relatively broad & heavy4 ,! pelage is co>se1 & (t5 hispid4 ,9 "s species ! hairs are s sp>sely di/ribut$ t ! body appe>s almo/ nak$1 & none has s d5se a cov]+ ( hair z d o!r g5]a4 ,! g5us occurs entirely )9 ! tropical life-zones1 & mo/ ( ! ext]nal features seem to be associat$ ) adaptation to tropical conditions4 ,! upp] incisor is unisulcate2 ! sulcus is usually ne> ! inn] bord] ( ! too?1 b 9 "s species 7subg5us ,or?ogeomys7 x is m m$ial1 & 9 a few individuals ) an extremely wide groove ! out] lip ( ! sulcus may actually rea* ! middle ( ! too?4 ,! groove is compress$ or op54 ,! premol> is a d\ble column unit$ at ! mid-po9t4 ,! two prisms are ( approximately equal size1 & ! lat]al re-entrant folds are s compress$ t _! sides are p>allel4 ,enamel plates cov] ! ant]ior surface & bord] ! re-entrant angles 9 bo? upp] & l[] premol>s4 ,z 9 o!r memb]s ( ! tribe1 ! l[] premol> has a f\r? enamel plate on ! po/]ior surface ( ! po/]ior lophid4 ,9 ! upp] premol>1 ! enamel plate is r$uc$ to a n>r[ blade on ! l+ual side ( ! loph z 9 ! liv+ species ( ! g5us ,zygogeomys4 ,9 ! subg5us ,or?ogeomys ! po/]ior plate is usually abs5t1 & o!rwise is n>r[ & ne> ! l+ual bord] ( ! too?4 ,ea* l[] mol>1 9 ! f9al /age ( we>1 consi/s ( a s+le elliptical column hav+ an enamel plate only on ! po/]ior surface4 ,! fir/ & second upp] mol>s are s+le elliptical columns hav+ "o enamel plate on ! ant]ior surface & ano!r on ! po/]ior surface4 ,! plates are sep>at$ by a tract ( d5t9e on ea* side ( ! too?4 ,! ?ird upp] mol> is p>tly bilophodont1 & ! two lophs are sep>at$ by a deep out] re-entrant fold4 ,9 _m ( ! species an inn] re-entrant fold also is reta9$1 b 9 ! adult too? x is less di/9ct ?an ! out]4 ,9 all ( ! species ! po/]ior loph is long & =ms a conspicu\s heel2 consequ5tly ! cr[n is significantly long] !n wide4 ,moreov]1 ! po/]ior loph has an enamel plate on ea* side4 ,! labial plate always bord]s ! out] re-entrant fold1 & 9 ! subg5us ,or?ogeomys is infrequ5tly sep>at$ into two small plates4 ,! m&ible is relatively long4 ,its masset]ic ridge is well develop$ & massive4 ,! basitemporal fossa is usually deep & well def9$2 x t5ds to be %all[ 9 ! subg5us ,or?ogeomys1 & 9 "y individuals is h>dly m ?an a slight depression4 ,key to ! ,subg5]a ( ,or?ogeomys ,a ,frontal wide & greatly inflat$2 no int]orbital con/riction2 enamel plate on po/]ior wall ( ,p#d usually abs5t1 al?\gh sometimes hav+ small plate1 re/rict$ to l+ual end ( wall4 ,subg5us ,or?ogeomys p4 #ebi ,a ,frontal n>r[ & n greatly inflat$2 int]orbital region decid$ly con/rict$2 enamel plate on po/]ior wall ( ,p#d always pres5t b %ort & re/rict$ to l+ual end ( wall4 ,b ,ant]ior m>g9 ( mesopt]ygoid fossa ev5 ) plane ( po/]ior wall ( ,m#c2 po/orbital b> weakly develop$2 ant]opo/]ior occlusal l5g? ( ,m#c equal to1 or less ?an1 comb9$ l5g? ( ,m#a & ,m#b4 ,subg5us ,het]ogeomys p4 #ecj ,b ,ant]ior m>g9 ( mesopt]ygoid fossa decid$ly beh9d plane ( po/]ior wall ( ,m#c2 po/orbital b> /rongly develop$2 ant]opo/]ior occlusal l5g? ( ,m#c m ?an comb9$ l5g? ( ,m#a & ,m#b4 ,subg5us ,macrogeomys p4 #eca ,subg5us ,or?ogeomys ,m]riam #ahie4 ,or?ogeomys ,m]riam1 ,n4 ,am]4 ,fauna1 #h3agb1 ,janu>y #ca4 ,type4--,geomys scalops ,?omas1 #ahid1 f ,tehuantepec1 ,oaxaca1 ,mxico4 ,*ronologic range4--,kn[n only f ! ,rec5t4 ,description4--,skull elongat$ & n>r[ 7_m skulls ( ne>ly uni=m bread? ?r\gh\t71 be+ extreme 9 doli*ocephalic specializations2 m&ibles long & n>r[1 rami n spread+ lat]ally1 be+ m ne>ly p>allel-sid$ ?an 9 o!r subg5]a2 angul> processes %ort2 bread? across zygomata n significantly exce$+ bread? across ma/oid processes 79 _m skulls consid]ably less72 int]orbital area rem>kably broad1 lack+ deep con/riction2 frontals betwe5 orbits greatly inflat$ lat]ally1 po/orbital prom95ce inconspicu\s2 mesopt]ygoid fossa ext5d+ to level ( po/]ior m>g9 ( ,m#c2 ,i hav+ sulcus broad] ?an 9 o!r subg5]a1 mo/ly on inn] half ( ant]ior surface b sometimes ov]lapp+ mid-l9e2 enamel plate lack+ f po/]ior wall ( ,p#d1 r>ely reta9+ n>r[ ve/ige ne> l+ual bord] ( po/]ior loph2 ,m#c hav+ di/9ct heel1 bicolumn> patt]n ) inn] re-entrant fold usually m9ute1 occlusal l5g? less ?an 9 o!r subg5]a1 l5g? less ?an comb9$ l5g?s ( ,m#a-b2 hair g5]ally co>se1 sometimes hispid1 sp>se1 9 l[l& =ms1 s sp>se z to imp>t appe>ance ( nak$ness4 ,ref]r$ species & subspecies4--,f\rte5 taxa3 ,or?ogeomys gr&is all5i ,nelson & ,goldman1 #aicj4 ,j\r4 ,mamm41 #aa3aef1 ,may #i4 ,type f ne> ,acapulco1 #bjjj ft41 ,gu]r]o4 ,or?ogeomys gr&is annexus ,nelson & ,goldman1 #aicc4 ,proc4 ,biol4 ,soc4 ,wa%+ton1 #df3aie1 ,octob] #bf4 ,type f ,tuxtla ,guti]rez1 #bfjj ft41 ,*iapas4 ,or?ogeomys gr&is c>bo ,goodw91 #aief4 ,am]4 ,mus4 ,novit41 #ageg3e1 ,m>* #h4 ,type f ,excurano1 #bejj ft41 ,c]ro de ,san ,p$ro1 #bj km4 ,w ,mixtequilla1 ,oaxaca4 ,or?ogeomys gr&is felip5sis ,nelson & ,goldman1 #aicj4 ,j\r4 ,mamm41 #aa3aeg1 ,may #i4 ,type f ,c]ro ,san ,felipe1 #aj mi4 ,n ,oaxaca1 ,oaxaca4 ,or?ogeomys gr&is huixtlae ,villa1 #aidd4 ,anal4 ,in/4 ,biol4 ,univ4 ,nac4 ,mxico1 #ae3cai4 ,type f ,f9ca ,lubeca1 #ab km4 ,,ne ,huixtla1 #hej m41 ,*iapas4 ,or?ogeomys gr&is gr&is 7,?omas1 #ahic74 ,ann4 ,mag4 ,nat4 ,hi/41 s]4 #f1 #ab3bgj1 ,octob]4 ,type f ,duez1 ,guatemala4 ,or?ogeomys gr&is latifrons ,m]riam1 #ahie4 ,n4 ,am]4 ,fauna1 #h3agh1 ,janu>y #ca4 ,type f ,guatemala1 exact locality unkn[n4 ,or?ogeomys gr&is nelsoni ,m]riam1 #ahie4 ,n4 ,am]4 ,fauna1 #h3agf1 ,janu>y #ca4 ,type f ,mt4 ,zempoaltepec1 #hjjj ft41 ,oaxaca4 ,or?ogeomys gr&is pluto ,lawr5ce1 #aicc4 ,proc4 ,new ,engl& ,zool4 ,club1 #ac3ff1 ,may #h4 ,type f ,c]ro ,cantoral1 nor? ( ,tegucigalpa1 ,honduras4 ,or?ogeomys gr&is scalops 7,?omas1 #ahid74 ,ann4 ,mag4 ,nat4 ,hi/41 s]4 #f1 #ac3dcg1 ,may4 ,type f ,tehuantepec1 ,oaxaca4 ,or?ogeomys gr&is soconusc5sis ,villa1 #aidi4 ,anal4 ,in/4 ,biol4 ,univ4 ,nac4 ,mxico1 #ai3bfg1 ,april #h4 ,type f ,f9ca ,exp]anza1 #gaj m41 #de km4 7by road7 ,,nw ,huixtla1 ,*iapas4 ,or?ogeomys gr&is gu]r]5sis ,nelson & ,goldman1 #aicj4 ,j\r4 ,mamm41 #aa3aeh1 ,may #i4 ,type f ,el ,limn1 9 valley ( ,ro de las ,balsas approximately #bj mi4 ,,nw ,la ,unin1 ,gu]r]o4 ,or?ogeomys cuniculus ,elliot1 #aije4 ,proc4 ,biol4 ,soc4 ,wa%+ton1 #ah3bcd1 ,decemb] #i4 ,type f ,zanatepec1 ,oaxaca4 ,or?ogeomys pygacan?us ,dickey1 #aibh4 ,proc4 ,biol4 ,soc4 ,wa%+ton1 #da3i1 ,febru>y #a4 ,type f ,cacaguatique1 #cejj ft41 ,dept4 ,san ,miguel1 ,el ,salvador4 ,subg5us ,het]ogeomys ,m]riam #ahie4 ,het]ogeomys ,m]riam1 ,n4 ,am]4 ,fauna1 #h3agi1 ,janu>y #ba4 ,type4--,geomys hispidus ,le ,conte1 #aheb1 f ne> ,jalapa1 ,v]acruz4 ,*ronologic range4--,late ,plei/oc5e1 ,wiscons9 deposits 7,san ,josecito ,cave local fauna1 ,nuevo ,len7 to ! ,rec5t4 ,description4--,skull doli*ocephalic 7less s ?an 9 ! o!r subg5]a72 zygomata m widely spread+ ?an 9 ,or?ogeomys2 ramus & angul> process %ort2 int]orbital area noticeably con/rict$2 frontals betwe5 orbits nei!r exceptionally broad or inflat$2 mesopt]ygoid fossa ext5d+ to level ( po/]ior m>g9 ( ,m#c2 ,i hav+ sulcus on inn] ?ird ( ant]ior surface usually n>r[] ?an 9 subg5us ,or?ogeomys2 enamel plate on po/]ior wall ( ,p#d re/rict$ to l+ual half ( loph2 ,m#c di/9ctly biprismatic1 po/]ior loph usually circumscrib$ by %all[ inn] re-entrant fold & out] deep fold well develop$ 9 all memb]s ( g5us2 po/]ior loph =m+ conspicu\s heel long] ?an 9 subg5us ,or?ogeomys2 occlusal l5g? equal to or slightly less ?an comb9$ l5g?s ( ,m#a-b2 hair co>se & hispid b nev] s sp>se z to imp>t appe>ance ( nak$ness4 ,ref]r$ species & subspecies4--,elev5 taxa3 99,or?ogeomys on]osus 7,russell1 #aifj74 ,univ4 ,kansas ,publ41 ,mus4 ,nat4 ,hi/41 #i 7#ba73edd1 ,janu>y #ad4 ,type f ,san ,josecito ,cave local fauna1 ,upp] ,plei/oc5e1 ,nuevo ,len4 ,or?ogeomys hispidus cayo5sis 7,burt1 #aicg74 ,occ4 ,pap]s ,mus4 ,zool41 ,univ4 ,mi*igan1 #cfe3a1 ,decemb] #af4 ,type f ,m\nta9 ,p9e ,ridge1 #ab mi4 ,s ,el ,cayo1 ,briti% ,honduras4 ,or?ogeomys hispidus *iap5sis 7,nelson & ,goldman1 #aibi74 ,proc4 ,bio4 ,soc4 ,wa%+ton1 #db3aea1 ,m>* #cj4 ,type f ,t5ejapa1 #af mi4 ,,ne ,san ,cri/obal1 ,*iapas4 ,or?ogeomys hispidus concavas 7,nelson & ,goldman1 #aibi74 ,proc4 ,biol4 ,soc4 ,wa%+ton1 #db3adh1 ,m>* #cj4 ,type f ,p9al de ,amoles1 ,qu]t>o4 ,or?ogeomys hispidus hispidus 7,le ,conte1 #aheb74 ,proc4 ,acad4 ,nat4 ,sci4 ,philadelphia1 #f3aeh4 ,type f ne> ,jalapa1 ,v]acruz4 ,or?ogeomys hispidus latiro/ris 7,hall & ,alv>ez1 #aifa74 ,anal4 ,escuela ,nac4 ,ci5cias ,biol41 #aj3aba1 ,decemb] #bj4 ,type f ,haci5da ,tamiahua1 ,cabo ,rojo1 ,v]acruz4 ,or?ogeomys hispidus negatus 7,goodw91 #aiec74 ,am]4 ,mus4 ,novit41 #afbj3a1 ,may #d4 ,type f ,gomez ,f]ias1 #acjj ft41 ab\t #de mi4 ,s ,ciudad ,victoria1 #aj km4 ,w ,pan ,am]ican ,highway1 ,tamaulipas4 ,or?ogeomys hispidus tehuantepecus 7,goldman1 #aici74 ,j\r4 ,wa%+ton ,acad4 ,sci41 #bi3agd1 ,april #ae4 ,type f m\nta9s #ab mi4 ,,nw ,santo ,dom+o & ab\t #fj mi4 ,n ,tehuantepec1 #afjj ft41 ,oaxaca4 ,or?ogeomys hispidus torridas 7,m]riam1 #ahie74 ,n4 ,am]4 ,fauna1 #h3ahc1 ,janu>y #ca4 ,type f ,*i*icaxtle1 ,v]acruz4 ,or?ogeomys hispidus yucatan5sis 7,nelson & ,goldman1 #aibi74 ,proc4 ,biol4 ,soc4 ,wa%+ton1 #db3aej1 ,m>* #cj4 ,type f ,campe*e1 ,campe*e4 ,or?ogeomys lanius 7,elliot1 #aije74 ,proc4 ,biol4 ,soc4 ,wa%+ton1 #ah3bce1 ,decemb] #i4 ,type f ,xu*il1 ,v]acruz4 ,subg5us ,macrogeomys ,m]riam #ahie4 ,macrogeomys ,m]riam1 ,n4 ,am]4 ,fauna1 #h3ahe1 ,janu>y #ca4 ,type4--,geomys het]odus ,pet]s1 #ahfe1 f ,co/a ,rica1 exact locality unkn[n4 ,*ronologic range4--,kn[n only f ! ,rec5t4 ,description4--,skull doli*ocephalic 9 v>y+ degree 7ov]lapp+ subg5]a ,or?ogeomys & ,het]ogeomys 9 ?is respect72 m&ibles elongat$1 n spread+ f> lat]ally2 angul> processes decid$ly %ort2 bread? across zygomata 9 no in/ance significantly exce$+ ma/oid bread?2 int]orbital area /rongly con/rict$2 frontals betwe5 orbits slightly inflat$ lat]ally 7especially 9 =ms hav+ m /rongly doli*ocephalic skulls72 po/orbital prom95ce conspicu\s2 ant]ior m>g9 ( mesopt]ygoid fossa t]m9at+ well beh9d ,m#c2 ,i hav+ n>r[ & deep sulcus entirely on inn] ?ird ( ant]ior surface2 enamel plate on po/]ior wall ( ,p#d re/rict$ to inn] half ( loph2 ,m#c bilophodont 7out] & inn] re-entrant folds ea* circumscrib+ a loph71 po/]ior loph rem>kably elongat$ & =m+ pron\nc$ heel1 l5g? ( cr[n m ?an comb9$ l5g?s ( ,m#a-b2 hair wooly 9 "s individuals1 h>% 9 o!rs b seldom hispid1 nev] s sp>se z 9 subg5us ,or?ogeomys2 "s species hav+ :ite m>k+s1 especially on lumb> region & head4 ,ref]r$ species & subspecies4--,elev5 taxa3 ,or?ogeomys het]odus c>tago5sis 7,goodw91 #aidc74 ,am]4 ,mus4 ,novit41 #abbg3b1 ,april #bb4 ,type f ,paso ,an*o1 ,prov9ce ,c>tago1 ,co/a ,rica4 ,or?ogeomys het]odus doli*ocephalus 7,m]riam1 #ahie74 ,n4 ,am]4 ,fauna1 #h3ahi1 ,janu>y #ca4 ,type f ,san ,jos1 ,co/a ,rica4 ,or?ogeomys het]odus het]odus 7,pet]s1 #ahfe74 ,monatsb4 preuss4 ,acad4 ,wiss41 ,b]l91 #ahfe3agg4 ,type f ,co/a ,rica1 exact locality unkn[n4 ,or?ogeomys cavator nigresc5s 7,goodw91 #aidc74 ,am]4 ,mus4 ,novit41 #abbg3c1 ,april #bb4 ,type f ,el ,muneco 7,ro ,nav>ro71 #aj mi4 ,s ,c>tago1 #djjj ft41 ,prov9ce ,c>tago1 ,co/a ,rica4 ,or?ogeomys cavator pansa 7,bangs1 #aijb74 ,bull4 ,mus4 ,comp4 ,zool41 #ci3dd1 ,april4 ,type f ,bogava 7 ,bugaba71 #fjj ft41 ,*iriqu1 ,panam4 ,or?ogeomys d>i5sis 7,goldman1 #aiab74 ,smi?sonian ,misc4 ,coll41 #fj7b73h1 ,septemb] #bj4 ,type f ,cana1 #bjjj ft41 m\nta9s ( ea/]n ,panam4 ,or?ogeomys und]woodi 7,osgood1 #aica74 ,field ,mus4 ,nat4 ,hi/41 ,publ4 #bie1 ,zool4 ,s]41 #ahe3adc1 ,aug4 #c4 ,type f ,alto de ,jabillo ,pirris1 betwe5 ,san ,g]onimo & ,pozo ,azul1 we/]n ,co/a ,rica4 ,or?ogeomys *]riei c>los5sis 7,goodw91 #aidc74 ,am]4 ,mus4 ,novit41 #abbg3c1 ,april #bb4 ,type f ,cat>atos1 ,san ,c>los1 ,alajuela1 ,co/a ,rica4 ,or?ogeomys *]riei *]riei 7,j4 ,a4 ,all51 #ahic74 ,bull4 ,am]4 ,mus4 ,nat4 ,hi/41 #e3ccg1 ,decemb] #af4 ,type f ,santa ,cl>a1 ,co/a ,rica4 ,or?ogeomys *]riei co/>ic5sis 7,m]riam1 #ahie74 ,n4 ,am]4 ,fauna1 #h3aib1 ,janu>y #ca4 ,type f ,pacu>e1 ,co/a ,rica4 ,or?ogeomys matagalpae 7,j4 ,a4 ,all51 #aiaj74 ,bull4 ,am]4 ,mus4 ,nat4 ,hi/41 #bh3ig1 ,april #cj4 ,type f ,pea ,blanca1 ,matagalpa1 ,nic>agua4 ,g5us ,pappogeomys ,m]riam #ahie4 ,pappogeomys ,m]riam1 ,n4 ,am]4 ,fauna1 #h3ade1 ,janu>y #ca4 #ahie4 ,cratogeomys ,m]riam1 ,n4 ,am]4 ,fauna1 #h3aej1 ,janu>y #ca4 ,type3 ,geomys m]riami ,?omas4 #ahie4 ,platygeomys ,m]riam1 ,n4 ,am]4 ,fauna1 #h3afb1 ,janu>y #ca4 ,type3 ,geomys gymnurus ,m]riam2 ,hoop]1 ,j\r4 ,mamm41 #bg3cig1 ,novemb] #be1 #aidf4 ,type4--,geomys bull]i ,?omas1 #ahib1 f ne> ,talpa1 we/ slope ,si]ra de ,mascota1 #hejj ft4 7actually ab\t #ejjj ft471 ,jalisco4 ,*ronologic range4--,late ,plioc5e1 f deposits ( e>ly ,blancan age 7,b5son local fauna1 ,arizona7 to ! ,rec5t4 ,h[ev] 9 ! ,plei/oc5e1 only late ,plei/oc5e records are kn[n1 & ,pappogeomys has n be5 f\nd 9 e>ly 7late ,blancan7 or middle 7,irv+tonian7 ,plei/oc5e local faunas4 ,presumably ! g5us 0 re/rict$ to ,mxico dur+ ! ,plei/oc5e until po/-,wiscons9 "t4 ,description & discussion4--,! size ranges f z little z 9 ! small] k9ds ( ,?omomys to ! maximum atta9$ 9 ! subfamily & mat*$ else:]e p]haps 9 only a few ( ! l>g] subspecies ( ,or?ogeomys gr&is4 ,dep5d+ on ! species & subg5us1 ! =m ( ! skull v>ies f g5]aliz$ to specializ$4 ,! g5]aliz$ skulls are %ort & n especially n>r[2 ! zygomatic ar*es are spread lat]ally s f> t ! bread? across !m exce$s ! bread? across ! ma/oid processes4 ,! mo/ specializ$ skulls are platycephalic & ! bread? across ! ma/oid processes equals or exce$s ! bread? across ! zygomatic ar*es 7ev5 s1 ! zygomatic ar*es are /ill relatively widespread74 ,9 correlation ) ! great bread? ( ! po/]ior "p ( ! cranium1 ! rami ( ! m&ibles div]ge widely po/]iolat]ally & ! angul> processes are rem>kably elongat$4 ,! ro/rum is mod]ately broad 9 mo/ species1 b n ne>ly s broad & heavy z 9 ,or?ogeomys4 ,! s+le deep1 m$ian sulcus on ! out] surface ( ! upp] incisor is slightly displac$ to ! inn] side ( ! too?4 ,! po/]ior surface ( ,p#d lacks enamel 7small ve/ige f\nd on l+ual end ( po/]ior wall 9 only two adult individuals--,,ua #cbfj & ,,ku #ajjddb1 ( ! subg5us ,pappogeomys72 ! o!r ?ree plates are fully develop$ z usual4 ,! p#d is provid$ ) f\r fully develop$ enamel plates1 9 ! patt]n *>act]i/ic ( ! tribe ,geomy9i4 ,9 ! p#d ( ! late ,plioc5e species 7,p4 b5soni7 ! re-entrant angles are op5 7obtuse71 a trait t is evid5tly primitive 9 ! ,geomy9i4 ,all ?ree l[] mol>s are s+le1 compress$1 elliptical columns ) enamel on only ! po/]ior surfaces4 ,m#a & ,m#b are also elliptical 9 cross-section & decid$ly ant]opo/]iorly compress$1 l ! l[] mol>s4 ,nev]!less1 ! enamel patt]n is v>iable2 enamel plates may be reta9$ completely across bo? ! ant]ior & po/]ior walls ( ,m#a & ,m#b or only ! ant]ior plate may be reta9$ )\t r$uction & ! po/]ior plate may be r$uc$ s t only a ve/ige is reta9$ on ! l+ual f\r? ( ! too? or ! po/]ior plate may be completely lo/4 ,m#c t5ds to rema9 at lea/ incompletely bilophodont by reason ( reta9+ a p]man5t labial re-entrant fold 9 mo/ species 7) exceptions 9 ,pappogeomys bull]i & "s old adults ( ,p4 ca/anops74 ,primitively ! occlusal surface ( ,m#c is subtriangul> 7subg5us ,pappogeomys71 b 9 ! ca/anops species-gr\p ( ! advanc$ subg5us ,cratogeomys1 ! po/]ior loph usually is r$uc$ & ! occlusal surface is quadri=m or obcordate4 ,curi\sly1 ! tr5d t[>ds r$uction ( ! po/]ior loph is rev]s$ 9 "o subspecies 7,p4 m]riami fulvesc5s7 &1 ! loph has elongat$ into a pron\nc$ heel 9 "s specim5s1 resembl+ ! condition 9 ,or?ogeomys4 ,! entire range ( v>iation occurs 9 ,p4 m4 fulvesc5s4 ,! subtriangul> patt]n is reta9$ 9 ! mo/ specializ$ species ( ,cratogeomys :]e t patt]n is associat$ ) extreme platycephaly 9 ! gymnurus species-gr\p4 ,9 mo/ species ! po/]ior loph supports two lat]al plates1 ! out] "o always bord]+ ! labial re-entrant fold4 ,9 ,pappogeomys bull]i & 9 ! ca/anops species-gr\p1 ! out] re-entrant fold ( ,m#c t5ds to be obsolete1 & ! too? becomes quadri=m or suborbiculate 9 "s individuals & loses ! bilophodont patt]n t *>act]izes o!r species4 ,! l+ual enamel plate is displac$ to ! po/]ior surface ( ! too?1 & "o or bo? plates may disappe> ) advanc+ age4 ,consequ5tly1 only ! ant]ior enamel plate rema9s 9 "s adults1 & con/itutes ! maximum degree ( r$uction ( enamel on ,m#c 9 ! ,geomy9ae4 ,9 _m adults ( ,pappogeomys bull]i1 ! enamel inve/m5t ( ! po/]ior loph is complete & ! two lat]al plates are connect$1 )\t int]ruption ar\nd ! po/]ior apex ( ! too?1 evid5tly repres5t+ ! ret5tion ( a primitive "* ( ! ance/ral l9eage4 ,! m#c ( ,p4 b5soni f ! late ,plioc5e is di/+ui%$ by m9ute lat]al inflections sugge/+ ! primitive biprismatic patt]n4 ,also ! po/]ior enamel plates ( m#a & m#b are rem>kably long1 ext5d+ ar\nd ! ends ( ! too?4 ,! associat$ upp] incisor 0 unisulcate z 9 ! mod]n species1 & ! basitemporal fossa ( ! m&ible is well develop$ & deep4 ,! l[] jaw is /\t & relatively %ort4 ,! masset]ic ridge is well develop$ & has an especially ?ick cre/4 ,! basitemporal fossa is deep4 ,9 mo/ liv+ species1 ! pelage is s(t & d5se1 b 9 "o species1 ,pappogeomys fumosus1 ! hairs are co>se & hispid some:at z 9 ,or?ogeomys4 ,key to ! ,subg5]a ( ,pappogeomys ,a ,enamel plates completely develop$ across po/]ior walls ( ,m#a & ,m#b1 except 9 "o species 7,p4 alcorni7 hav+ enamel re/rict$ to l+ual f\r? 9 ,m#a2 sagittal cre/ lack+ ow+ to impressions ( temporal muscles rema9+ sep>at$ 7ev5 9 old adults72 zygomata sl5d]1 & )\t platelike expansion at lat]al angle4 ,subg5us ,pappogeomys p4 #ecd ,a ,enamel lack+ on po/]ior walls ( ,m#a & ,m#b2 pron\nc$ sagittal cre/ develop$ 9 adults ( bo? sexes by union ( temporal impressions at middorsal l9e2 zygomata /\t & wide1 ) lat]al angle exp&$ into broad plate4 ,subg5us ,cratogeomys p4 #ece ,subg5us ,pappogeomys ,m]riam #ahie4 ,pappogeomys ,m]riam1 ,n4 ,am]4 ,fauna1 #h3ade1 ,janu>y #ca4 ,type4--,geomys bull]i ,?omas1 #ahib1 f ne> ,talpa1 we/ slope ,si]ra de ,mascota1 #hejj ft4 7actually ab\t #ejjj ft471 ,jalisco4 ,*ronologic range4--,late ,plioc5e 7,b5son local fauna1 ,arizona7 to ,rec5t1 b no specim5s kn[n f ,plei/oc5e4 ,description4--,small1 approximately same size z small subspecies ( ,?omomys umbr9us b =efeet l>g] & claws long]2 skull ( g5]aliz$ %ape1 broad1 relatively %ort1 smoo?ly r\nd$1 n especially compress$ dorso-v5trally2 zygomatic bread? great b n exce$+ ma/oid bread?2 zygomata relatively sl5d] = geomyid & lack+ platelike expansions at lat]al angles2 ro/rum relatively n>r[2 sagittal cre/ lack+1 ow+ to impressions ( temporal muscles rema9+ sep>at$2 angul> process ( m&ible n especially elongat$2 enamel plates ext5d+ completely across po/]ior wall ( ,m#a & ,m#b1 except 9 "o species1 ,p4 alcorni1 :]e po/]ior plate ( ,m#a rema9s only on l+ual f\r? ( po/]ior wall 7rema9d] ( plate lack+72 ) we>1 plates sometimes exceptionally ?9 completely across po/]ior face ( ,m#b & especially ,m#a 9 a few individuals ( ,p4 bull]i mu* z ,paulson 7#aifa3ach-aci7 describes 9 ext9ct ,geomys tob95sis2 "o or bo? plates r>ely disappe> 9 f9al /ages ( attrition 9 old individuals result+ 9 same d5tal patt]n f\nd 9 ,cratogeomys2 ,m#a & ,m#b reta9+ enamel plate on ant]ior wall ?r\gh\t life2 ,m#c usually subtriangul> 9 cross-section b sometimes suborbiculate or ovoid1 cr[n slightly bilophodont ow+ to %all[ness ( labial re-entrant angle 9 mod]n species2 po/]ior loph ( ,m#c n especially elongat$ & cr[n n significantly long] ?an wide2 bo? lat]al enamel plates ( ,m#c usually well develop$ & approximately equal 9 l5g?1 occasionally plates r$uc$ 9 l5g? & r>ely "o or bo? plates are lo/ ) we> 9 old individuals2 pat* ( :iti% or buffy hairs surr\nd+ nose ( mo/ individuals4 ,! primitive "* ( ! l[] d5tition1 z describ$ 9 ! species acc\nt above1 sugge/ t ,cratogeomys ,pappogeomys b5soni ,gidley %\ld be ref]r$ to ! subg5us ,pappogeomys r ?an ,cratogeomys4 ,only ! upp] d5tition w\ld make positive id5tification possible2 h[ev]1 ref]5ce to ! subg5us ,pappogeomys seems to be ! be/ arrangem5t at ?is "t4 ,ref]r$ species4--,?ree 7"o ext9ct73 99,pappogeomys b5soni 7,gidley71 #aibb4 ,u4 ,s4 ,geol4 ,surv4 ,pr(4 ,pap]s1 #aca3abc4 ,type f ,b5son local fauna 7late ,plioc5e71 ,co*ise ,c\nty1 ,arizona4 ,pappogeomys alcorni ,russell1 #aieg4 ,univ4 ,kansas ,publ4 ,mus4 ,nat4 ,hi/41 #i7aa73cei4 ,type f #d mi4 ,w ,mazamitla1 ,jalisco4 ,pappogeomys bull]i ,?omas1 #ahib4 ,ann4 ,mag4 ,nat4 ,hi/41 ,s]4 #f1 vol4 #aj3aif1 ,augu/4 ,type f ne> ,talpa1 we/ slope ( ,si]ra ,madre de ,mascota1 ,jalisco4 ,subg5us ,cratogeomys ,m]riam #ahie4 ,cratogeomys ,m]riam1 ,n4 ,am]4 ,fauna1 #h3aej1 ,janu>y #ca4 #ahie4 ,platygeomys ,m]riam1 ,n4 ,am]4 ,fauna1 #h3afb1 ,janu>y #ca4 ,type3 ,geomys gymnurus ,m]riam1 #ahib4 ,type4--,geomys m]riami ,?omas1 #ahic1 f ,s\!rn ,mxico1 probably 9 ,valley ( ,mxico4 ,*ronologic range4--,late ,plei/oc5e1 f ,wiscons9 deposits 7,san ,josecito ,cave1 ,nuevo ,len1 ,upp] ,b]c]ra1 ,mxico1 & ,burnet ,cave1 ,new ,mexico1 local faunas7 to ! ,rec5t4 ,description4--,size m$ium to l>ge2 skull becom+ angul> & rugose ) age1 & t5d+ t[>ds platycephaly & dorso-v5tral compression2 zygomata /\t1 ea* be>+ platelike expansion at ant]olat]al angle into :i* ant]ior end ( jugal becomes mortic$2 bread? across zygomata great relative to l5g? ( skull2 ro/rum relatively broad2 squamosals exp&+ m$ially ) age ev5tually gr[+ ov] lat]al p>ts ( p>ietals1 & sometimes also exp&+ lat]ally displac+ po/gl5oid not*2 sagittal cre/ well develop$ 9 adults ( bo? sexes1 b especially high & bladelike 9 males2 lambdoidal cre/ prom95t 9 all b "y animals1 hav+ dorsal outl9e broadly convex po/]iorly 9 mo/ species b /rongly s9u\s 9 gymnurus-gr\p2 enamel plate on po/]ior wall ( ,p#d abs5t2 enamel plates pres5t only on ant]ior walls ( ,m#a & ,m#b2 ,m#c v>i=m 9 occlusal %ape 7z describ$ 9 species acc\nt71 ei!r subtriangul> 7gymnurus-gr\p71 quadri=m or obcordate 7ca/anops-gr\p1 ) exceptions z not$ be=e72 lat]al plates ( ,m#c usually pres5t 9 all species1 labial plate approximately z long z l+ual plate 9 gymnurus-gr\p 7l t 9 subg5us ,pappogeomys7 or di/9ctly %ort] 9 ca/anops-gr\p 7labial plate sc>cely ext5d+ beyond bord] ( labial re-entrant fold72 "o or bo? lat]al plates t5d+ to disappe> ) we> 9 ca/anops-gr\p1 ) l+ual plate usually disappe>+ fir/2 bread? across angul> processes cle>ly m ?an bread? across zygomatic processes1 especially 9 gymnurus-gr\p4 ,rem>ks4--,9 ! species ( ! ca/anops-gr\p ! skulls c be spok5 ( z g5]aliz$ & ! lea/ platycephalic ( ! subg5us4 ,inde$1 ! species ( ! ca/anops-gr\p are h>dly m specializ$ 9 ?is respect ?an is ! subg5us ,pappogeomys4 ,9 ^! skulls ! bread? across ! squamosal processes is less ?an t across ! zygomatic ar*es1 al?\gh ! two dim5sions are almo/ equal 9 "s examples ( ,p4 m]riami ( ! ca/anops-gr\p 7:]e squamosal bread? v>ies f #he to #ih ( zygomatic bread?74 ,9 ! species hav+ m>k$ platycephalic skulls 7gymnurus species-gr\p7 ! bread? across ! squamosal processes equals or exce$s ! bread? across ! zygomatic ar*es 7squamosal bread? r>ely #ig to #ii ( zygomatic bread?71 except 9 ,p4 z9s]i & ,p4 tylorh9us zodius4 ,! v>iable "* ( ! ?ird upp] mol> z betwe5 species sugge/s t ?is too? is pres5tly und]go+ active evolution4 ,! /ructure ( ?is too?1 al?\gh diff]+ betwe5 taxa1 is rem>kably /able 9 o!r k9ds ( ,geomy9i4 ,! mo/ rem>kable modification ( ,m#c 9 ,cratogeomys is ! obcordate patt]n develop$ 9 ,p4 m]riami ( ! ca/anops-gr\p4 ,! po/]ior loph & entire too? is %ort5$ some:at resembl+ 9 %ape t ( ,?omomys4 ,moreov]1 ! po/]ior loph is twi/$ labially2 consequ5tly1 its po/]ior surface n[ =ms ! labial bord] ( ! weakly def9$ po/]ior loph4 ,ow+ to ! torsion1 ! l+ual enamel plate has be5 rotat$ to ! po/]ior surface ( ! too?4 ,!re=e1 ! too? is provid$ ) two transv]se enamel plates1 includ+ ! plate on ! ant]ior wall ( ! too?4 ,! labial plate is greatly r$uc$1 its total surface be+ re/rict$ to ! small labial inflection4 ,! highly specializ$ obcordate ,m#c is n f\nd 9 ! mo/ specializ$ platycephalic skulls *>act]i/ic ( ! gymnurus species-gr\p4 ,in/ead ! gymnurus-gr\p reta9s ! primitive subtriangul> patt]n )\t significant modification4 ,ref]r$ species4--,sev53 ca/anops species-gr\p ,pappogeomys ca/anops 7,baird1 #aheb74 ,report ,/anbury's ,exp'd4 to ,great ,salt ,lake1 p4 #cac1 ,june4 ,type f ,prairie road to ,b5t's ,=t1 ne> pres5t t[n ( ,las ,animas1 ,colorado4 ,pappogeomys m]riami 7,?omas1 #ahic74 ,ann4 ,mag4 ,nat4 ,hi/41 s]4 #f1 #ab3bga1 ,octob]4 ,type f s\!rn ,mexico1 probably ,valley ( ,mxico 7see ,m]riam1 #ahie3aeb74 gymnurus species-gr\p ,pappogeomys fumosus 7,m]riam1 #ahib74 ,proc4 ,biol4 ,soc4 ,wa%+ton1 #g3afe1 ,septemb] #bi4 ,type f #c mi4 ,w ,colima1 ,colima4 ,pappogeomys gymnurus 7,m]riam1 #ahib74 ,proc4 ,biol4 ,soc4 ,wa%+ton1 #g3aff1 ,septemb] #bi4 ,type f ,zapotlan 7,ciudad ,guzman71 ,jalisco4 ,pappogeomys neglectus 7,m]riam1 #aijb74 ,proc4 ,biol4 ,soc4 ,wa%+ton1 #ae3fh1 ,m>* #bb4 ,type f ,c]ro de la ,cal5tura1 ab\t #h mi4 ,,nw ,p9al de ,amoles1 ,qu]t>o4 ,pappogeomys tylorh9us 7,m]riam1 #ahie74 ,n4 ,am]4 ,fauna1 #h3afg1 ,janu>y #ca4 ,type f ,tula1 ,hidalgo4 ,pappogeomys z9s]i 7,goldman1 #aici74 ,j\r4 ,mamm41 #bj3ia1 ,febru>y #ae4 ,type f ,lagos1 ,jalisco4 ,,phylog5y ,,( ,,! ,,geomyidae ,! fossil record ( ! ,geomyidae provides a sequ5ce ( morphotypes1 ea* repres5t+ a /age 9 ! phyletic developm5t ( ! family4 ,mo/ ( ! pres]v$ specim5s probably repres5t ! /uf5reihe r ?an ! ahn5reihe1 z ,simpson 7#aiec3bai-bbj7 po9ts out4 ,ev5 s1 ! /uf5reihe closely approximates ! g5]al tr5d ( evolution1 & ! level ( /ructural organization 9 ! diff]5t /ages ( phyletic developm5t may be asc]ta9$4 ,! actual ance/ral s]ies ( mo/ l9eages probably w rema9 unkn[n1 b hopefully "s ( ! exi/+ gaps w be fill$ by future discov]ies4 ,f ! e/abli%$ record1 sev]al cle>ly def9$ l9eages c be di/+ui%$2 9 fact ! sequ5ce ( orig91 patt]n ( evolution1 & specializations1 ( ! pr9cipal l9eages are reasonably well express$4 ,primitive ,morphotype ,9 ! e>lie/ kn[n geomyids f ! ,upp] ,oligoc5e & ,l[] ,mioc5e1 ! premol>s & mol>s are biprismatic & bilophodont4 ,9 rod5ts1 ?is is itself a specializ$ patt]n1 & is ?\ght to h evolv$ f a m primitive sextitub]culate prototype by ! union ( individual cusps1 & probably also cuspules1 =m+ ! two transv]se enamel lophs4 ,! primitive1 common ance/or ( ! ,geomyidae & ,het]omyidae ) sextitub]culate tee? 9 ! e>ly ,t]ti>y is unkn[n4 ,z soon z geomyids atta9$ ! e>ly bilophodont /age ( evolution1 ! basic morphological /ructure ( ! family 0 e/abli%$4 ,! family probably fir/ became cle>ly di/+ui%$ f o!r ,geomyoidea at ?is /age4 ,9 ! e>ly bilophodont /ages ( evolution1 ow+ to ! relatively deep valley betwe5 !m1 ! two columns probably fail$ to unite 9 ! normal cycle ( we>1 z !y d 9 all lat] geomyids4 ,griphomys describ$ by ,wilson 7#aidj3ic7 f ! late ,eoc5e ( ,cali=nia1 has a bilophate patt]n 9 :i* ! ant]ior & po/]ior lophs are sep>at$ by a p]si/5t transv]se valley4 ,! occlusal patt]n ( ,griphomys closely resembles a /age ?r\gh :i* ! ance/ors ( ! e>ly ,mioc5e geomyids mu/ h pass$ 9 _! pre-,mioc5e evolution1 z ,wilson sugge/s 7#aidi3aae-aaf74 ,al?\gh he 7#aidj3ie2 #aidi3aaj-aah7 t5tatively ref]r$ ,griphomys to ! sup]family ,geomyoidea & ,simpson 7#aide3hj7 w5t s f> z to ref] x to ! family ,geomyidae1 ) a notation ( inc]tae s$is1 its exact relation%ip to ! pocket goph]s is unc]ta94 ,h[ev]1 ! /ructure ( ! mol>i=m d5tition ( ,griphomys does n exclude x f ! phyletic ance/ry ( ! ,geomyidae4 ,9 subsequ5t /ages ( evolution ! ant]ior & po/]ior columns become unit$4 ,!reby "p ( ! valley floor betwe5 ! transv]se prisms 0 progressively elevat$1 to ! /age :]e attrition on ! occlusal surface w\ld unite ! two columns4 ,on ! unworn enamel cap ( liv+ geomyids ! two transv]se enamel folds are sep>at$ by a %all[ b well def9$ valley1 briefly reflect+ ! anci5t ance/ral patt]n4 ,union ( ! lophs may h be5 ei!r at ! mid-po9ts ( ! two columns or at ! edge ( _! protom]es4 ,a protom]e is ! half ( a too? conta9+ ! protocone or protoconid--l+ual side ( upp] too? & labial side ( l[] too?4 ,! p>am]e is ! opposite half ( a giv5 too?--labial side ( upp] too? & l+ual side 9 l[] too?4 ,see ,mill] & ,gidley1 #aiah3dcd4 ,union ( ! columns at ! mid-po9ts w\ld h produc$ ! figure-#h occlusal patt]n 7or ,h-patt]n71 :i* is *>act]i/ic ( ! e>ly ,mioc5e ,geomy9ae 7,dikkomys74 ,union ( ! two columns at ! protom]es w\ld h produc$ ! ,u-%ap$ patt]n ( ! ,entopty*9ae1 :i* also occurr$ 9 ! e>ly ,mioc5e & 7 contempor>y ) ! e>lie/ ,geomy9ae4 ,s9ce pre-,mioc5e geomyids are unkn[n1 ! actual phyletic developm5t ( ! d5tition is a matt] ( speculation4 ,probably ! developm5t ( ! two div]g5t l9eages1 "o lead+ to ! ,entopty*9ae & ! o!r to ! subfamily ,geomy9ae1 occurr$ 9 ! ,oligoc5e 7z depict$ 9 ,fig4 #c74 ,( ! two l9eages1 ! subfamily ,geomy9ae1 9 my view1 is ! m primitive & less specializ$4 ,support = ?is view is furni%$ by a recon/ruction ( ! patt]n ( occlusal we> 9 ,dikkomys & ,pliosaccomys1 especially on ! fir/ & second mol>s4 ,9 ,dikkomys1 ! ant]ior & po/]ior column fir/ unite ne> _! mid-po9ts 9 ! fir/ /ages ( we> ?us produc+ a figure-#h %ap$ 7,h-%ap$7 occlusal patt]n 9 ! premol> & all ?ree mol>s4 ,evid5tly 9 ! fir/ two upp] mol>s1 ! columns unite clos] to _! l+ual m>g9s ?an _! mid-po9ts1 b at any rate bo? out] & inn] re-entrant folds are evid5t at ?is /age ( we>4 ,) cont9u$ attrition on m#a & m#b ( ,dikkomys1 ! ant]ior & po/]ior columns second>ily unite at ! edge ( _! labial m>g9s ?us enclos+ a fossette ( enamel 9 ! labial half ( ! too?4 ,! lat]al coalesc5ce at ! ends ( ! protom]es occurs because ( ! %all[ v]tical dep? ( ! labial re-entrant fold1 & ! fossette itself does n rea* ! base ( ! cr[n & ) cont9u$ we> x too w\ld disappe>1 b n until ! la/ /ages ( we>1 at lea/ 9 ,dikkomys mat!wi4 ,! l+ual re-entrant fold is deep1 & !re=e1 p]si/5t ?r\gh all /ages ( we>4 ,al?\gh ! am\nt ( we> requir$ = its effacem5t w\ld be great1 ! occlusal configuration ( ! fir/ & second l[] mol>s 9 ,dikkomys c\ld be ev5tually gr\nd d[n to a ,u-patt]n z 9 ! entopty*ids4 ,only "o upp] mol> ( ,dikkomys1 ! fir/1 has be5 recov]$ 7see ,wood1 #aicf3bc1 fig4 #cb;,b74 ,al?\gh ! too? is 9 an e>ly /age ( we>1 ! l+ual valley is m9ute4 ,less attrition ?an requir$ 9 m#a & m#b w\ld progressively r$uce ! l+ual fold until x too w\ld ess5tially =m a ,u-patt]n1 p]haps reta9+ a slight l+ual inflection4 ,h5ce1 ! fir/ upp] mol> becomes a mirror image ( ! fir/ l[] mol>1 & ! second upp] mol> probably _h ! same patt]n z ! fir/ 7at lea/ x does s 9 ,pliosaccomys74 ,bo? ( ! lat]al re-entrant folds ( ! premol> are deep v]tically1 & consequ5tly w\ld n disappe> ) occlusal we>4 ,!re=e1 ! ,h-patt]n ( ! premol>s is reta9$ ?r\gh\t life4 ,! m#c 7,m#c unkn[n = ,dikkomys or ,pliosaccomys7 also has deep lat]al folds2 h5ce1 x too reta9s ! ,h-patt]n 9 all /ages ( attrition1 al?\gh ! i/hmus betwe5 ! two prisms may become wid] 9 ! f9al phases ( we> 7z x does 9 ,pliosaccomys74 ,9 ,pliosaccomys1 ! /ages ( we> are ess5tially ! same z ^? describ$ = ,dikkomys1 except t ! ant]ior & po/]ior loph ( ! fir/ & second mol>s t5d to unite clos] to "o side ( ! too?1 l+ual side 9 upp] mol>s & labial 9 l[]4 ,only a slight inflection ( ! re-entrant fold is evid5t on ! side ( union1 & ! inflection disappe>s 9 ! fir/ phases ( we> z ! columns unite4 ,concomitant ) ! lat]al %ift 9 ! initial po9t ( coalesc5ce ( ! transv]se lophs1 ! occlusal p5etration ( ! re-entrant fold f ! opposite side increases 9 horizontal dep?1 & ! fold ext5ds m$ially m ?an half way across ! occlusal surface1 ?us =m+ a patt]n ess5tially l t ( ! entopty*ids4 ,! ,u-patt]n 9 ,pliosaccomys appe>s 9 ! initial /ages ( we> )\t go+ ?r\gh an e>li] ,h-patt]n z is ! case 9 its ,mioc5e ance/ors ( ! g5us ,dikkomys1 unless ! m9ute inflection is consid]$ z indicative ( t /age4 ,! two columns ( ! premol> & m#c are jo9$ ne> _! mid-po9ts z 9 ,dikkomys2 !re=e1 !y reta9 _! primitive ,h-patt]n1 a feature unique to ! ,geomy9ae4 ,! evolution>y tr5d t[>d an ontog5etically e>li] ,u-patt]n 9 ! fir/ two mol>s 9 ! primitive l9eage ( ! ,geomy9ae sugge/s t ! ,u-patt]n *>act]i/ic ( ! ,entopty*9ae 0 simply an e>li] t5d5cy t[>d ! same specialization t occurr$ lat] 9 ! subfamily ,geomy9ae4 ,if s1 e>ly entopty*9es w\ld h be5 *>act]iz$ by an ,h-patt]n 9 ! fir/ /ages ( attrition1 l ,dikkomys1 & lat] develop$ union at ! edge ( ! protom]es4 ,h[ev]1 9 ! entopty*9es1 all ! mol>i=m d5tition1 & n m]ely ! fir/ & second mol>1 became specializ$2 consequ5tly ! ,u-patt]n 0 produc$ on ! occlusal surfaces ( ea* ( ! *eek tee?4 ,z 9 ,pliosaccomys1 ! transitional phase1 9 :i* ! two columns 7 unit$ at _! mid-po9ts1 0 ev5tually elim9at$ f ! patt]n ( we> & only ! ,u-patt]n1 t n[ appe>$ 9 ! initial /ages ( we>1 0 reta9$4 ,9 ! entopty*9es ( ! e>ly ,mioc5e !re is no sugge/ion ( ! ,h-patt]n t *>act]izes ! ,geomy9ae1 except 9 ! position ( ! cusps be=e we> 9 ! l[] mol>s ( ,pleurolicus sulcifrons1 :i*1 accord+ to ,wood 7#aicf3f71 sugge/s ! ,h-patt]n4 ,9 e>li] unkn[n ,oligoc5e /ages ( evolution1 ! prisms possibly unit$ fir/ at _! mid-po9ts1 & ! columns may h jo9$ at ! side ( ! too? only 9 ! t]m9al /ages ( we>4 ,! ,u-patt]n ( pre-,mioc5e entopty*9es1 !re=e1 may h become ! dom9ant occlusal patt]n only 9 ! lat] /ages ( phyletic developm5t4 ,accord+ to ! rec5tly express$ views ( sev]al paleontologi/s1 ! ,entopty*9ae con/itute ! primitive l9eage ( ! family & ! e>ly ,geomy9ae con/itute a specializ$ (f%oot ( ! entopty*9e ance/ral assemblage4 ,! /ructure ( ! ,entopty*9ae1 especially ( ! less advanc$ g5]a1 closely approximates t ( ! hypo!tical primitive morphotype4 ,b1 accord+ to my view1 ! subfamily ,geomy9ae con/itutes ! ance/ral assemblage & its /ructure is ess5tially t ( ! primitive morphotype ( ! family4 ,at any rate ! /ructure ( ! e>ly geomy9es m closely approximates ! /ructure ( ! ance/ral /ock ?an ! m div]g5t entopty*9es4 ,!re=e1 ! g5us ,dikkomys ( ! e>ly ,mioc5e1 ! fir/ kn[n geomy9e1 is consid]$ to be a g5]aliz$ geomyid1 &1 al?\gh x is a contempor>y ( ! m specializ$ entopty*id assemblage1 is consid]$ to be m closely alli$ to ! ance/ral /ock4 ,! entopty*9es 7 ! dom9ant & mo/ highly diff]5tiat$ geomyids ( ! e>ly & middle ,mioc5e4 ,nev]!less1 !y became ext9ct 9 ! middle ,mioc5e1 & ! geomy9es ( t "t surviv$ & lat] gave rise to ! mod]n pocket goph]s4 ,!re=e1 ! e>ly hi/ory ( ! family ,geomyidae is *>act]iz$ by an e>ly radiation & tr5d t[>d specialization1 foll[$ by survival ( ! less specializ$ ,geomy9ae & ext9ction ( ! m specializ$ ,entopty*9ae4 ,entopty*id ,radiation ,! mo/ abundant geomyids ( ! e>ly & middle ,mioc5e1 ! ,entopty*9ae1 consi/$ ( at lea/ #bd species 7see ,wood1 #aicf3d-be7 classifi$ 9 f\r g5]a3 ,pleurolicus1 ,gregorymys1 ,grang]imus1 & ,entopty*us4 ,! g5]a 7 ess5tially contemporane\s 7see ,figure #c74 ,ev5 s1 ! subfamily 0 morphologically v>i$1 po9t+ to an e>li] orig9 9 ! ,oligoc5e 7actually a "p ( ! ,john ,day ,fauna1 includ+ ,pleurolicus may be correlat$ ) late ,oligoc5e ,:itneyian age7 foll[$ by a relatively rapid radiation includ+ all f\r g5]a 9 ! e>ly ,mioc5e4 ,two g5]a1 ,pleurolicus & ,gregorymys1 cont9u$ into ! ,middle ,mioc5e 7,hem+=dian74 ,?is div]g5ce1 specialization1 & subsequ5t radiation sugge/ t ! entopty*9es evolv$ into a new major adaptive zone1 9 ! s5se describ$ by ,simpson 7#aide3aii-bjf74 ,! radiation is correlat$ geographically & temporally ) ! s\?w>d retreat ( ! ,neotropical flora ( ! ,t]ti>y f ! we/]n ,unit$ ,/ates & s\?w>d movem5t ( ! ,arctic flora ( ! ,t]ti>y 7see ,axl]od1 #aiej2 ,b]ry1 #aicg3ca-df2 ,*aney1 #aidg3aci-adh2 & ,k5deigh1 #aifa3bhj-bhc74 ,9 ! e>ly ,t]ti>y ! ,neotropical-t]ti>y ge(lora occurr$ nor?w>d to at lea/ #di latitude 9 we/]n ,nor? ,am]ica1 & ! boreal ,arctic-t]ti>y flora 0 re/rict$ to a circumpol> zone4 ,! s\?w>d & ea/w>d %ift ( ! ,neotropical-t]ti>y flora1 associat$ ) ! dry+ & *ill+ ( ! cont95t1 began 9 ! middle or late ,oligoc5e & 0 concurr5t ) ! div]g5ce & radiation ( ! ,entopty*9ae4 ,beg9n+ 9 late ,oligoc5e & cont9u+ at lea/ into middle ,mioc5e1 mo/ ( ! region 9 :i* ! entopty*9es occurr$ 0 occupi$ by ! ,arcto-t]ti>y ge(lora ( :i* ! temp]ate =e/ division contribut$ ! dom9ate plant associations4 ,! maples1 *e/nuts1 dogwoods1 bee*es1 walnuts1 oaks1 elms1 bir*es1 & sycamores ( t flora 7 ! =]unn]s ( today's ea/]n decidu\s =e/4 ,x is my view t ! entopty*9es became adapt$ to ! conditions ( ?is paleoecological environm5t & radiat$ rapidly 9 ! ,arik>eean :5 ! major *ange occurr$ 9 climax vegetation4 ,! ance/ral /ock ( ! ,geomy9ae 0 n s successful 9 ! ,arcto-t]ti>y climax1 & mo/ ( x probably 0 displac$ s\?w>d along ) ! tropical flora4 ,! skeleton 9 ! entopty*9es is n s /rongly fossorial z 9 ! mod]n geomyids 7,wilson1 #aidi3aag71 & ^! e>ly geomyids probably 7 semi-fossorial ) some:at ! same burr[+ habits z ^? ( ! liv+ m\nta9 beav] 7,aplodontia74 ,inasmu* z ! morphology & taxonomy ( ! entopty*9es 7 discuss$ 9 detail by ,cope 7#ahhd7 & review$ lat] by ,wood 7loc4 cit471 !re is no ne$ to rec\nt ! details "h4 ,accord+ to ,wood 7op4 cit41 #bg-bh71 ,pleurolicus occupi$ a c5tral position 9 ! entopty*id radiation & p]haps appe>$ slightly e>li] ?an ! o!r g5]a4 ,wilson 7#aidi7 sugge/$ t ! l[] "p ( ! ,john ,day may actually be ,upp] ,oligoc5e r ?an ,l[] ,mioc5e1 & ?is arrangem5t is foll[$ "h4 ,also1 ,pleurolicus is less specializ$ ?an ! o!r g5]a & occurs 9 deposits ( bo? ! ,great ,pla9s & ! ,pacific ,coa/4 ,gregorymys1 also little specializ$1 occurr$ only on ! ,great ,pla9s4 ,! m specializ$ g5]a1 ,grang]imus & ,entoptycus1 evid5tly appe>$ some:at lat] ?an ,pleurolicus & evolv$ f x4 ,except = a record f s\!rn ,texas report$ rec5tly by ,hibb>d & ,wilson 7#aiej3fba-fbc7 & ! new species describ$ by ,mac,donald 7#aifc3ahb7 f ! ,%>ps ,=mation ( ,s\? ,dakota 7e>ly ,arik>eean71 ,grang]imus is kn[n only f ! ,pacific coa/4 ,entoptycus 0 re/rict$ to ! ,pacific ,coa/ 7,john ,day fauna74 ,entoptycus is ! mo/ specializ$ ( ! kn[n g5]a2 x has pron\nc$ fossorial adaptations1 especially 9 ! skull4 ,its mol>i=m tee? are rootless & ev]-gr[+ z 9 ! mod]n geomy9es4 ,moreov]1 ! cont9u\s enamel b&s on only mod]ately worn tee? become sep>at$ 9 ! f9al /ages ( we> into ant]ior & po/]ior enamel plates by tracts ( d5t9e t ext5d t[>d ! cr[n on ! sides ( ea* too?4 ,?is ext5sion 0 made possible by ! union ( ! two columns at bo? ! l+ual & labial m>g9s ( ! too? =m+ an ,o-patt]n1 & ! cr[n is ess5tially monoprismatic save = ! isolat$ enamel fossette 9 ! c5t] ( ! too?4 ,! fossette is all t rema9s ( ! lat]al re-entrant fold t *>act]iz$ ! prec$+ ,u-patt]n ( ! e>li] /ages ( we>4 ,late 9 ! sequ5ce ( we>1 ! ant]ior enamel plate is lo/ 9 ! l[] mol>s & ! po/]ior plate 9 ! upp] mol>s4 ,! ,u-patt]n *>act]izes ! f9al /ages ( attrition 9 ! o!r g5]a ( ! ,entopty*9ae2 none develop$ ! d5tal specializations se5 9 ,entoptycus4 ,rootless1 ev]-gr[+ *eek tee?1 discont9u\s enamel patt]ns1 & monoprismatic mol>s 7 n evolv$ 9 ! subfamily ,geomy9ae until ! late ,plioc5e4 ,phyletic ,tr5ds 9 ,subfamily ,geomy9ae ,! subfamily ,geomy9ae is made up ( ?ree gr\ps1 recogniz$ taxonomically = ! fir/ "t 9 ?is acc\nt z tribes--,dikkomy9i1 ,?omomy9i1 & ,geomy9i 7= full discussion ( classification1 see previ\s acc\nt74 ,! phylog5y propos$ by me is illu/rat$ 9 ,figure #c4 ,! tribe ,dikkomy9i is *>act]iz$ by g5]aliz$ & primitive features t toge!r =m ! basic /ructural f\ndation ( ! subfamily4 ,evolution )9 ! ,dikkomy9i result$ 9 ! acquisition & p]fection ( fossorial adaptations4 ,! ,?omomy9i & ,geomy9i are consid]ably m specializ$ ?an ! ance/ral ,dikkomy9i f :i* !y evolv$4 ,! ,geomy9i are cle>ly m specializ$ ?an ! ,?omomy9i1 sugge/+ clos] aff9ity betwe5 ! ,?omomy9i & ! ,dikkomy9i ?an betwe5 ! ,geomy9i & ! ,dikkomy9i4 ,! specializations 9 ! d5tition & ! associat$ *anges 9 ! skull ( ! ,?omomy9i & ,geomy9i p]mit m effici5t ma/ication ( fibr\s vegetation4 ,along ) ^! specializations1 fossorial adaptations inh]it$ f ! ,dikkomy9i are reta9$ )\t notewor?y modification4 ,dikkomys1 ! e>lie/ kn[n g5us ( ! tribe ,dikkomy9i1 c be tak5 z a />t+ po9t ( evolution = ! subfamily ,geomy9ae4 ,! ,plioc5e g5us ,pliosaccomys is ! only o!r kn[n geomy9e hav+ primitive features closely resembl+ ^? ( ,dikkomys4 ,! relatively close b previ\sly unrecogniz$ relation%ip betwe5 ,dikkomys & ,pliosaccomys c be und]/ood :5 patt]ns ( we> on ! occlusal surfaces ( ! *eek tee? are tak5 into acc\nt4 ,x appe>s t ,pliosaccomys desc5d$ f ,dikkomys-l /ock1 if n ,dikkomys itself4 ,al?\gh ,dikkomys is t[>ds ! beg9n+ ( ?is phyletic sequ5ce & ,pliosaccomys t[>ds ! end ( ! sequ5ce1 ! primitive features %>$ by ! two provide a g5]aliz$ morphotype = ! subfamily ,geomy9ae4 ,9 ! mol>i=m d5tition1 an almo/ complete s]ies ( /ages ( we> 9 ,pliosaccomys has be5 pres]v$1 & ^? ( ,dikkomys c be recon/ruct$ ) reasonable accuracy f ^? t are kn[n 7see ,fig4 #d73 7#a7 ,9 ! initial /age ( we> 9 ,dikkomys ! ant]ior & po/]ior columns are sep>at$ by an int]v5+ valley 7,fig4 #d;,a71 & ! occlusal surface ( ea* column be>s a loph ( d5t9e surr\nd$ by a r+ ( enamel3 protoloph on ! ant]ior column & metaloph on ! po/]ior column ( ! upp] tee? 7protolophid & hypolophid 9 correspond+ positions 9 ! l[] tee?74 ,actually ?is /age is n pres]v$ 9 ! kn[n mat]ial ( ,dikkomys1 b does occur 9 bo? geomy9es & entopty*9es 9 all /ages ( evolution1 & x mu/ h also occurr$ 9 ,dikkomys 9 ord] = ! next two /ages1 :i* are pres]v$1 to h develop$4 7#b7 ,! occlusal surfaces are gr\nd d[n to a level :]e ! enamel loops ( ! two columns jo9 at _! mid-po9ts1 ?us =m+ an ,h-%ap$ patt]n 7,fig4 #d;,b71 or m exactly a patt]n resembl+ a figure #h4 ,probably ?is 0 ! primitive patt]n 9 ! f9al /age ( we> 9 ! geomyid ance/or ( ! ,oligoc5e4 ,illu/ration3 ,,fig4 #c4 ,diagram depict+ geologic range & probable phyletic relation%ips ( ! family ,geomyidae4 ,da%$ l9es repres5t p>ts ( l9eages t are n repres5t$ by fossil records1 & solid l9es repres5t p>ts ( l9eages v]ifi$ by actual specim5s4 ,"q m>ks indicate unc]ta9ty ( sugge/$ ance/ry ( kn[n taxa4 ,! relation%ips )9 ! subfamily ,entopty*9ae are modifi$ aft] ,wood 7#aicf71 & ! temporal range ( ! ,mioc5e geomyids h be5 adju/$ to agree ) curr5t /ratigraphic correlations4 ,h5ce1 ,pleurolicus1 ,gregorymys & ,dikkomys are illu/rat$ z rang+ into ! ,hem+=dian1 r ?an be+ conf9$ to ! ,arik>eean 7see ,mac,donald1 #aifc1 & ,black1 #aifa74 7#c7 ,9 ! pre-f9al /age ( we>1 ! ant]ior & po/]ior lophs ( ! fir/ & second mol>s unite second>ily at ! edge ( _! protom]es 7labial side 9 ! l[] & l+ual 9 ! upp]71 ?us enclos+ an isolat$ enamel fossette 7,fig4 #d;,c74 ,lat]al union occurs 9 ! l[] tee? because ! v]tical dep? ( ! labial re-entrant angle is less ?an ! dep? ( ! l+ual re-entrant fold4 ,9 ! upp] tee? ! rev]se is true4 ,! re-entrant angle on "o side ( ! premol> is z deep v]tically z ! angle on ! o!r side ( t too?1 & bo? rea* ! base ( ! cr[n2 !re=e1 !y d n disappe> at any /age ( attrition4 ,! same p]ta9s 9 ! ?ird l[] mol>4 7#d7 ,9 ! f9al /age ( we> 7,fig4 #d;,d71 ! enamel fossette disappe>s z a result ( cont9u$ attrition on ! occlusal surface 9 ! upp] s]ies4 ,! fossette may v>y some:at 9 v]tical dep? 9 m#a & m#b1 b ! am\nt ( we> requir$ = its effacem5t w\ld be great] ?an 9 ! upp] tee?4 ,!re=e1 ^u we>1 ! ,u-patt]n w\ld become *>act]i/ic ( ! f9al /age 9 ,m#a 7& probably also ,m#b71 b ! modifi$ ,h-patt]n describ$ 9 ,fig4 #d;,c w\ld prevail 9 m#a & m#b4 ,p]haps1 9 extremely worn tee?1 ! labial fossette ( m#a & m#b w\ld disappe>4 ,if ?is advanc$ /age ( effacem5t is obta9$1 !n ! two columns w\ld be unit$ across ! entire surface ( _! protom]es f ! c5t] ( ! cr[n to its labial edge1 & ! occlusal patt]n w\ld be 9 ! %ape ( a ,u4 ,! occlusal patt]n1 at lea/ 9 ,m#a & ,m#b1 9 ! f9al /ages ( we> 9 ,dikkomys resembles t 9 ! subfamily ,entopty*9ae1 b ! ,u-patt]n develops on only ! fir/ & probably ! second mol> 9 ,dikkomys & n on all ( ! *eek tee? z x does 9 ! entopty*9es4 ,judg+ f ! mat]ial t has be5 describ$1 ! ,u-patt]n did n develop 9 ! l[] tee? ( ,dikkomys until ! ,hem+=dian 7,d4 woodi71 upp] ,rosebud1 & specim5s ( ,d4 mat!wi f ! e>li] ,arik>eean1 l[] ,h>rison1 sugge/ t ! modifi$ ,h-patt]n1 ) second>y coalesc5ce at ! edge ( ! protom]es1 p]si/$ ?r\gh\t life1 )\t develop+ ! ,u-patt]n 9 ! f9al /ages ( we>4 ,ess5tially ! same patt]ns ( we> *>act]ize ! g5us ,pliosaccomys1 except t ! e>li] /ages 7 telescop$ & ! second /age 0 omitt$ :ile ano!r 7f9al7 /age 0 add$4 ,! /ages are recon/ruct$ 9 sequ5ce 9 figure #d1 & all are bas$ on pres]v$ d5titions1 z foll[s3 7#a7 ,! fir/ phases ( we> produc$ ! patt]n 7,fig4 #d;,e & ,i7 describ$ = ,dikkomys 9 ! previ\s acc\nt 7,fig #d;,a74 7#b7 ,a small additional am\nt ( we> produc$ ! #bnd /age 7,fig4 #d;,f & ,j7 *>act]iz$ by a ,u-patt]n1 =m$ by union ( ! ant]ior & po/]ior columns at ! edge ( ! protom]es ( ! fir/ & second mol>s1 bo? above & bel[1 )\t fir/ =m+ an ,h-%ap$ patt]n4 ,union at ! mid-po9ts ?us 0 omitt$ f ! sequ5ce ( we> 9 ^! two tee?4 ,9 ! premol>s & ?ird mol>s ! primitive ,h-patt]n did =m1 z 9 ,dikkomys4 ,! patt]n ( we> 9 ! fir/ two mol>s is ! same z 9 ! entopty*9es ( ! e>ly ,mioc5e4 ,! tr5d ( evolution ?r\gh :i* ! ,pliosaccomys l9eage pass$ mu/ h featur$ a progressively e>li] union at ! edge ( ! too? until ! lat]al coalesc5ce occurr$ simultane\sly ) ! m$ian union4 ,at t /age1 emphasis 0 %ift$ to ! union at ! edge ( ! too?1 & ev5tually ! tee? fail$ to unite at _! mid-po9ts & ! ,u-patt]n develop$ directly4 ,!re=e1 ! horizontally deep re-entrant fold t sep>ates ! two lophs ( ! ,u-patt]n is equival5t to "o fold plus ! apex ( ! opposite fold4 7#c7 ,! horizontal re-entrant fold ( ! ,u-patt]n 0 rem>kably %all[ v]tically & disappe>$ ) little additional we>4 ,?us ! two p>ts ( ,m#a1 & also ( ,m#b1 are unit$ into a s+le column except = a slight inflection on ! labial side & ?is is true also ( m#a & m#b except = a slight inflection on ! l+ual side 7,fig4 #d;,g & ,k74 ,! inflection appe>s to h p]si/$ 9 ! upp] tee? 7,fig4 #d;,h71 b evid5tly ) slight we>1 disappe>$ 9 ! l[] tee? 7,fig4 #d,l74 ,! f9al monocolumn> patt]n 0 atta9$ e>ly ontog5etically1 evid5tly be=e ! p]man5t premol> _h fully erupt$2 h5ce1 ! e>li] /ages occurr$ only 9 transition1 p]si/$ = only a brief int]val 9 ! tee? ( juv5iles1 & ! f9al /age develop$ 9 ! "y animal & la/$ ?r\gh\t ! re/ ( its life 9 ,pliosaccomys4 ,9 ,dikkomys ! two columns nev] unit$ into a s+le column1 & a bilophodont occlusal patt]n p]si/$ ?r\gh\t life4 ,! e>ly phyletic developm5t ( ! subfamily ,geomy9ae took place 9 ! tribe ,dikkomy9i f ! e>ly ,mioc5e into ! e>ly ,plioc5e4 ,comp>$ ) ! rapid evolution ( ! specializations t di/+ui% ! ,entopty*9ae1 ! /ructural *anges 9 ! e>ly ,geomy9ae occurr$ at a rem>kably sl[ rate4 ,9 fact ! l9eage *ang$ b little f ,dikkomys to ,pliosaccomys1 9 p>ts ( ! animal t c be comp>$1 z illu/rat$ by ! l[-cr[n$ & root$ *eek tee?1 ! cont9u\s enamel b&s1 ! lack ( groov+ ( ! upp] incisor1 ! ret5tion ( ! primitive ,h-patt]n1 bo? above & bel[1 9 ! premol> & ?ird l[] mol>1 & ! ridges & fossae ( ! m&ible to :i* ! muscles ( ma/ication atta*4 ,! only major *anges detect$ 9 ! kn[n fragm5ts are 9 ! patt]n ( we> & ! f9al configuration ( ! fir/ & second mol>s1 z describ$ above4 ,! unification ( ! two lophs 9 ea* ( ^! two tee? into a s+le column 0 a significant /ep 9 ! evolution ( ! ,geomy9ae1 & is a /age betwe5 ! primitive bilophodont patt]n ( ! e>ly & middle ,mioc5e geomy9es hav+ cont9u\sly bicolumn> tee? & ! monolophodont patt]n 9 ! mod]n pocket goph]s ( bo? l9eages 9 :i* ^! tee? consi/ ( a s+le column 9 all b ! initial /ages ( we>4 ,! monocolumn> /ructure ( ! fir/ & second mol>s 9 ! f9al /ages ( we>1 !re=e1 is clos] to t 9 ! l9eage ( ,?omomys ?an x is to t ( ,dikkomys4 ,o!r specializations 9 ! d5tition ( ,pliosaccomys1 especially 9 m#a & m#b :]e ! ,h-patt]n has be5 completely elim9at$ f ! sequ5ce ( we>1 are too f> advanc$ = ,pliosaccomys to h giv5 rise to ! tribe ,geomy9i4 ,! tee? 9 ! imm$iate ance/or ( ! ,geomy9i mu/ h be5 less specializ$ 9 m#a & m#b1 p]haps ab\t z 9 ,dikkomys4 ,9 ! m#a & m#b ( ! tribe ,geomy9i1 ! ,h-patt]n is =m$ 9 ! initial /ages ( we>2 !re=e1 9 ! e>ly ,plioc5e ance/or1 pres5tly unkn[n 9 ! fossil record1 ! ,h-patt]n probably 0 pres5t4 ,ev5 s1 ! ance/or ( ! ,geomy9i & t ( ,pliosaccomys probably 7 closely alli$ o!rwise1 & bo? probably _h atta9$ ! highly specializ$ fossorial adaptations *>act]iz+ all mod]n pocket goph]s1 be=e ! div]g5ce ( ,pliosaccomys & ! ,geomy9i took place4 ,! evid5ce po9ts to a major div]g5ce ( ! geomy9es t liv$ 9 ! late/ ,mioc5e or ! e>ly ,plioc5e 7probably ! latt]7 & t gave rise to ! two mod]n l9eages1 ,?omomy9i & ,geomy9i 7see ,fig4 #c74 ,"o1 ! mo/ primitive ( ! two1 gave rise to ! ,?omomy9i l9eage t ev5tually evolv$ into ,?omomys4 ,pliosaccomys is closely alli$ to ! ance/ry ( ?is l9eage1 al?\gh x is probably n ! actual ance/or1 z m5tion$ previ\sly4 ,aside f ! a=em5tion$ specializations ( ! fir/ & second mol>s1 ! features ( ! ,?omomy9i are less advanc$ ?an 9 ! o!r specializ$ l9eage 7tribe ,geomy9i74 ,primitive traits reta9$ 9 ! tribe ,?omomy9i 7& also *>act]i/ic ( ! ance/ral tribe ,dikkomy9i7 are3 7#a7 ,small size1 9 g5]al no l>g] ?an ! ance/ral morphotype2 7#b7 lack ( groov+ on ! upp] incisor 7al?\gh a slight rudim5t>y groove is develop$ r>ely 9 "s liv+ species72 7#c7 ret5tion ( ant]ior & po/]ior enamel plates 9 l[] & upp] *eek tee?2 7#d7 premol>s hav+ widely op5 re-entrant folds2 7#e7 smoo? & g5]aliz$ skull lack+ m>k$ angul>ity1 regosity or cre/+ 7nei!r ! sagittal nor ! lambdoidal cre/ are ord9>ily well develop$ except 9 ,?omomys bulbivorus72 7#f7 =efoot small1 less modifi$ = digg+ ?an 9 ! ,geomy9i4 ,illu/ration3 ,,fig4 #d4 ,draw+s ( ! mol>i=m d5titions ( ,dikkomys & ,pliosaccomys 7,tribe ,dikkomy9i7 depict+ ! patt]ns ( we> on ! occlusal surfaces4 ,ontog5etically1 ! /ages ( we> are arrang$ f left to "r 9 ea* r[4 ,/ages n repres5t$ by actual specim5s h be5 c>efully recon/ruct$ f in=mation provid$ by kn[n /ages 9 ! sequ5ce ( we> & ! d5titions ( o!r geomy9es4 #e4 ,a-,d4 ,dikkomys woodi1 "r l[] too?-r[1 includ+ p#d-m#c4 ,patt]ns bas$ on ,no4 ,p#bfbhd 7,,fmnh7 f ,upp] ,rosebud 7,middle ,mioc5e71 ,%annon ,co41 ,s\? ,dakota 7,b above74 ,e-,h4 ,pliosaccomys dubius1 left upp] too?-r[1 includ+ ,p#d-,m#b 7,m#c unkn[n74 ,patt]ns bas$ on ,nos4 #agih & #agii 7,,lam7 f ,smi?s ,valley 7,middle ,plioc5e71 ,lyon ,co41 ,nevada4 ,i-,l4 ,pliosaccomys dubius1 "r l[] too?-r[1 includ+ p#d-m#c4 ,patt]ns bas$ on ,nos4 #agif 7holotype71 #ahjd1 & #ahjf 7,,lam7 f ,smi?s ,valley 7,middle ,plioc5e71 ,lyon ,co41 ,nevada4 ,! l9eage ( ! ,?omomy9i is ess5tially rectil9e> & )\t ! major bran*+ se5 9 ! tribe ,geomy9i4 ,! "o g5us1 ,?omomys1 appe>s fir/ 9 ! ,upp] ,plioc5e 7e>ly ,blancan "t71 & ! specializations *>act]iz+ ! l9eage _h already develop$ by t "t4 ,evid5tly1 ! e>ly /ages ( div]g5ce f ! ance/ral /ock result$ 9 ! developm5t ( rootless1 ev]-gr[+1 m hypsodont *eek tee?1 simplification ( ,m#c1 & enl>gem5t ( ! masset]ic ridge on ! m&ible4 ,! enamel inve/m5t on ! sides ( ! mol>i=m tee? is int]rupt$ ow+ to intrusion ( tracts ( d5t9e on ! sides ( ea* column4 ,ev5 s1 complete ant]ior & po/]ior plates are reta9$ on all ( ! *eek tee? 7,fig4 #e1 ,k & ,l7 & !re is no tr5d t[>d additional loss ( enamel z 9 ! ,geomy9i4 ,! enamel on ! sides ( ! column has little functional value1 & its elim9ation probably r$uces friction dur+ ! ant]opo/]ior movem5ts ( ! l[] jaw1 !reby increas+ ! effici5cy ( ! cutt+ blades on ! ant]ior & po/]ior wall ( ! too?4 ,! simplification ( ,m#c 0 a*iev$ by union ( ! two columns ( ! primitive patt]n into a s+le column & oblit]ation ( bo? ! labial & l+ual re-entrant folds 9 ! fir/ /ages ( we>4 ,! adult too? 7see ,fig4 #e,l7 is )\t trace ( ! bilophate patt]n & is n elongat$2 !re=e1 its /ructure is ess5tially ! same z t ( ! fir/ & second upp] mol>s4 ,9 ! ,?omomy9i1 ! two lophs ( ! unworn mol>s unite entirely across ! wid? ( _! surfaces ) ! fir/ traces ( we> 7see ,fig4 #e1 ,i & ,j71 ow+ to ! %all[ & uni=m dep? ( ! transv]se valley4 ,9 ! mol>s1 ! f9al patt]n is acquir$1 !re=e1 be=e ! decidu\s premol> has be5 replac$ by ! p]man5t too?4 ,a relatively %all[ re-entrant inflection betwe5 ! ends ( ! p>am]es sometimes is reta9$1 al?\gh x also w disappe> ) slight additional we>4 ,!re=e1 bo? lophs t5d to unite completely ) ! fir/ /ages ( we> 9 ! ,?omomy9i1 ?us omitt+ bo? ,u & ,h patt]ns f ! sequ5ce ( we>4 ,?is is ! highe/ degree ( specialization atta9$ 9 ! ,geomyidae 9 reg>d to ! patt]ns ( we>1 s9ce a sequ5ce ( bilophodont patt]ns appe> 9 bo? ! ,dikkomy9i & ,geomy9i be=e ! monoprismatic patt]n is develop$4 ,illu/ration3 ,,fig4 #e4 ,draw+s ( mol>i=m d5titions repres5tative ( ! tribes ,geomy9i & ,?omomy9i depict+ patt]ns ( we> on ! occlusal surface4 ,a-,d repres5t1 9 ontog5etic sequ5ce f left to "r1 upp] too?-r[s ( ! tribe ,geomy9i4 ,e-,h repres5t1 9 ! same sequ5ce ( /ages1 l[] too?-r[s ( ! tribe ,geomy9i4 ,i-,l repres5ts bo? upp] & l[] too?-r[s ( bo? pre-f9al & f9al /ages ( we> 9 ! tribe ,?omomy9i4 ,all #e4 ,a & ,e4 ,geomys burs>ius majusculus1 ,no4 #bidh 7,,ku71 ,d\glas ,co41 ,kansas4 ,"r upp] 7,a7 includ+ ,,dp#d-,m#c2 l[] left 7,e7 includ+ dp#d-m#c4 ,b & ,f4 ,pappogeomys bull]i burti1 ,no4 #ajjddd 7,,ku71 #aj mi4 ,,nnw ,b>ra de ,navidad1 ,jalisco4 ,"r upp] 7,b7 includ+ ,p#d-,m#c2 "r l[] 7,f7 includ+ p#d-m#c 7bo? ,p#d & p#d ) unworn enamel caps74 ,c & ,g4 ,pappogeomys bull]i alb9asus1 ,no4 #cajdd 7,,ku71 #aj mi4 ,s & #h mi4 ,w ,guadalaj>a1 ,jalisco4 ,"r upp] 7,c7 includ+ ,p#d-,m#c2 "r l[] 7,g7 includ+ p#d-m#c4 ,d & ,h4 ,pappogeomys bull]i alb9asus1 ,no4 #cajjb 7,,ku71 ,w side ,la ,v5ta1 #ac mi4 ,w & #d mi4 ,n ,guadalaj>a1 ,jalisco4 ,"r upp] 7,d7 includ+ ,p#d-,m#c2 "r l[] 7,h7 includ+ p#d-m#c4 ,i & ,j4 ,?omomys talpoides bridg]i1 ,no4 #fhfe 7,,ku71 #b mi4 up ,m9k ,creek1 ,pocatella1 ,bannock ,co41 ,idaho4 ,left upp] 7,i71 ,,dp#d-,m#c2 left l[] 7,j71 dp#d-m#c4 ,k & ,l4 ,?omomys talpoides fossor1 ,no4 #acbje 7,,ku71 ,wasson ,ran*1 #c mi4 ,e ,cre$e1 ,m9]al ,co41 ,colorado4 ,"r l[] 7,k71 p#d-m#c2 left upp] 7,l71 ,p#d-,m#c4 ,relation%ip ( ! ,geomy9i ) ! ance/ral ,dikkomy9i is mo/ cle>ly demon/rat$ 9 ! sequ5ce ( we> on ! occlusal surfaces ( ! mol>s4 ,z 9 all geomyids1 ! upp] "p ( ! cr[n is biprismatic 9 ! newly erupt$ too?1 & ! two columns are sep>at$ by an int]v5+ valley4 ,) slight attrition on ! unworn enamel cap1 ! weakly develop$ cusps m]ge & =m a transv]se enamel loop on ea* ( ! two columns 7see ?ird mol> 9 ,fig4 #e1 ,a & ,e71 ea* loop enclos+ a core ( d5t9e t _h become expos$4 ,! valley betwe5 ! two columns is %all[1 & ^u fur!r we> ( ! too?1 ! two loops unite4 ,! two columns become jo9$ at diff]5t po9ts 9 ! upp] & l[] mol>s dep5d+ on ! v>y+ dep? ( ! valley 9 diff]5t tee?4 ,!re=e1 upp] & l[] mol>s develop di/9ctly diff]5t occlusal configurations4 ,9 ! l[] mol>s1 ! patt]n *>act]i/ic ( ,dikkomys 7,fig4 #d;,c7 is pres]v$ )\t significant modification1 z illu/rat$ 9 an immature specim5 ( ,geomys 7see ,fig4 #e;,e74 ,! ,h-patt]n & modifi$ ,h-patt]n are develop$ 9 ! same sequ5ce ( we> 9 ! ,geomy9i4 ,a juv5al female 7n illu/rat$71 ,,ku #bica1 provides an example ( ! int]m$iate ,h-patt]n4 ,9 ?is specim51 ! protolophid & hypolophid ( ! left m#b are unit$ only at _! mid-po9ts1 indicat+ t ! patt]n ( we> occurs 9 ! same sequ5ce 9 ! ,geomy9i z x did 9 ! ,mioc5e g5us ,dikkomys4 ,aft] ! two columns h become unit$ at _! mid-po9ts1 a second>y union is =m$ at ! edge ( _! protom]es1 ?us enclos+ ! enamel fossette z illu/rat$ 9 ,figure #e;,e 7?is is ! modifi$ ,h-patt]n m5tion$ above74 ,h[ev]1 ! fossette itself is %all[ & soon disappe>s ) slight we>4 ,at ?is /age1 ! occlusal configuration w\ld be 9 a ,u-patt]n 7m#a 9 ,fig4 #e;,e74 ,! l+ual re-entrant fold is also %all[ 9 v]tical dep?2 !re=e1 x is oblit]at$ by we> foll[+ ! eradication ( ! labial fossette4 ,consequ5tly1 ! two columns are unit$ into "o4 ,9 m#c 7see ,figs4 #e;,e1 ,f1 & ,g71 ! two columns m]ge by progressive lat]al expansion ( ! m$ial i/hmus4 ,9 ! fir/ & second upp] mol>s1 ! two columns unite across ! entire surface ( _! protom]es f ne> ! l+ual edge ( ! cr[n to ne> its c5t]4 ,a m9ute inn] inflection may be tempor>ily reta9$ 9 "s tee?4 ,at ?is /age 7see ,fig4 #e;,b71 ! p>am]es are /ill sep>at$ by ! labial fissure1 & ! occlusal patt]n is 9 ! %ape ( a ,u1 resembl+1 b n exactly duplicat+1 ! pre-f9al patt]n ( ,ml & ,m#b 9 ! g5us ,pliosaccomys 7see ,fig4 #d;,h74 ,! labial fissure is %all[1 &1 ) fur!r we>1 ! inflection is worn away & ! p>am]es also unite1 !reby =m+ a monoprimatic cr[n 9 ! f9al /age4 ,9 ,m#c1 ! two lophs fir/ become unit$ ne> ! edge ( _! protom]es 7see ,fig4 #e;,b71 !re=e =m+ a ,u-patt]n simil> to t develop$ 9 ,ml & ,m#b ( ,pliosaccomys4 ,! connection ( ! two lophs is n directly at ! end ( ! protom]e2 consequ5tly a %all[ l+ual inflection rema9s4 ,! l+ual edge ( ! valley is also %all[1 &1 ) cont9u$ we> a second union ( ! two lophs takes place ne> ! ends ( _! p>am]es1 & ! deep]1 int]ior "p ( ! valley rema9s z an isolat$ enamel fossette 7see ,fig4 #e;,c74 ,! two prim>y lophs ( ! too? are n[ jo9$ ne> bo? sides1 hav+ %all[ l+ual & labial re-entrant angles on ! sides & ! enamel isl& 9 ! c5t]4 ,) cont9u$ effacem5t ( ! occlusal surface1 ! fossette w be eradicat$1 & ! patt]n ( ! occlusal surface w become ! p>tially biprismatic patt]n ( ! f9al /ages 7adult7 ( we> 7see ,fig4 #e;,d74 ,m#c's ( ,dikkomys & ,pliosaccomys are n kn[n2 h[ev]1 x seems reasonable to assume t ! patt]n ( we> 9 ! ,m#c ( ,dikkomy9i 0 n ess5tially diff]5t f t ( ! ,geomy9i1 except t x is likely t ! ,u-patt]n ( ! second /age ( we> 9 ! ,geomy9i 0 probably ! f9al /age 9 ! g5us ,dikkomys4 ,judg+ f ! pre-f9al /ages ( we>1 ! d5tition ( ! ,geomy9i provides a curi\s comb9ation ( patt]ns t resemble 9 "p ! ,mioc5e g5us ,dikkomys & 9 "p ! e>ly & middle ,plioc5e g5us ,pliosaccomys4 ,!re is no significant v>iation 9 ! premol>s or ?ird mol>s 7at lea/ 9 ! l[] tee?7 ( ! ,geomy9ae f ! e>ly ,mioc5e to late ,plioc5e2 !re=e1 deviations ( major significance are 9 ! "* ( ! fir/ & second mol>s4 ,9 ! ,geomy9i1 ! patt]ns ( we> ( m#a & m#b are ! same z ^? ( ,dikkomys1 & are di/9ctly diff]5t f ^? ( ,pliosaccomys :]e ! two columns fir/ unite at ! edge ( _! protom]es to =m a ,u-patt]n1 r ?an at _! mid-po9ts to =m an ,h-patt]n4 ,ev5 ?\gh ! int]m$iate /ages ( ontog5y 9 m#a & m#b ( ,pliosaccomys & ! ,geomy9i are entirely diff]5t1 ! bicolumn> cr[ns ( bo? ev5tually unite1 ^u we>1 into a s+le column4 ,on ! o!r h&1 ! patt]ns ( ,m#a & ,m#b 9 ! ,geomy9i mo/ closely resemble ^? ( ,pliosaccomys1 r ?an ,dikkomys4 ,9 ?is reg>d x %\ld be po9t$ out t ! upp] mol>s ( ,dikkomys are pres5tly repres5t$ by only "o too?1 an ,m#a 9 an e>ly /age ( we>4 ,z describ$ already1 ! patt]ns ( ,m#a-b evid5tly w\ld be mirror images ( m#a-b 9 correspond+ /ages ( we>4 ,h[ev]1 ! initial union ( ! two columns1 9 ! ,m#a t is kn[n1 is some:at to ! l+ual side ( c5t] & ! relatively small l+ual valley does n rea* ! base ( ! cr[n1 indicat+1 t ev5tually ) we>1 ! two columns ( ,dikkomys might h become unit$ across ! entire surface ( _! protom]es z 9 ,pliosaccomys4 ,ev5 s1 ! two columns ( ,m#a d initially jo9 clos] to _! mid-po9ts ?an !y d 9 ,pliosaccomys1 &1 if !y did actually unite across _! protom]es1 ! union w\ld h occurr$ ) subsequ5t we>4 ,t is1 ! fir/ occlusal patt]n w\ld be ,h-%ap$ 7b ) ! connection clos] to ! l+ual ?an ! labial side71 z 9 m#a & m#b1 & x w\ld become ,u-%ap$ only aft] additional we>4 ,?is sequ5ce ( patt]ns ( ,m#a & ,m#b1 z already po9t$ out1 does n p]ta9 9 ,pliosaccomys or ! ,geomy9i1 s9ce ! ,u-patt]n is =m$ ) ! fir/ union ( ! two columns at ! edge ( _! protom]es1 & ! primitive ,h-patt]n is nev] develop$1 unless "o c\nts ! slight l+ual inflection1 t occasionally is =m$ j aft] ! two columns unite1 z be+ indicative ( ! primitive patt]n4 ,z 9 ! l[] tee?1 ! bicolumn> cr[ns ( e>ly ontog5y 9 bo? ,pliosaccomys & ! ,geomy9i become ev5tually unit$1 ) we>1 into a s+le column4 ,bas$ ^u ! =ego+ evid5ce1 x w\ld seem likely t ! ,geomy9i evolv$ f an e>ly ,plioc5e 7p]haps late ,mioc5e7 ,dikkomy9i ance/or t _h evolv$ ! specializations ( ,m#a & ,m#b t *>act]ize its relative1 ,pliosaccomys1 b _h n also evolv$ ! specializations ( m#a & m#b t di/+ui% ,pliosaccomys4 ,!re=e1 ! ance/or ( ! ,geomy9i diff]$ f ! ,pliosaccomys-,?omomy9i l9eage 9 its ret5tion1 unmodifi$1 ( ! primitive patt]ns 9 m#a & m#b t *>act]iz$ ! e>lie/ kn[n ,geomy9es 7,dikkomys74 ,! same patt]ns are pres]v$ 9 m#a & m#b ( its mod]n desc5d5ts1 ! liv+ ,geomy9i4 ,9 ! ,pliosaccomys-,?omomy9i l9eage ! patt]n ( m#a & m#b are entirely diff]5t1 z describ$ above4 ,! e>lie/ record ( ! ,geomy9i is ! ext9ct g5us ,pliogeomys 7see ,fig4 #f7 9 ! late/ ,hemphillian 7middle ,plioc5e7 & e>lie/ ,blancan 7late ,plioc5e74 ,pliogeomys is m primitive ?an any mod]n g5us ( ! ,geomy9i1 seems to h be5 a late survivor ( ! primitive /ock1 b 0 itself probably a collat]al l9eage & n on ! direct l9e ( desc5t4 ,! *eek tee? 9 ,pliogeomys are root$ & less hypsodont ?an 9 ! late ,plioc5e examples ( ! mod]n g5]a1 & ! ant]ior enamel plate ( ! l[] mol>s %[s no indication ( r$uction1 z w\ld be expect$ if ,pliogeomys 7 9 ! direct l9e ( evolution4 ,sep>ation ( ,pliogeomys f ! ma9 /em ( ! ,geomy9i probably occurr$ aft] sev]al specializations _h already be5 a*iev$ by ! ,geomy9i4 ,two inh]itances might h be5 groov+ on ! upp] incisors & "s r$uction 9 am\nt ( enamel on ! sides ( ! *eek tee?4 ,! d5t9e tracts on ! sides ( ! *eek tee? ( ,pliogeomys are n>r[ 7see ,fig4 #g;,a7 & b>ely sep>ate ! enamel blades & !re is no disc]nible r$uction 9 ! ant]ior enamel blades on its l[] mol>s4 ,^? blades evid5tly 7 lo/ 9 ! ma9 l9eage be=e ! ,plei/oc5e radiation ( ! liv+ g5]a took place4 ,pliogeomys is 9 an int]m$iate /age 9 evolution1 & 0 n s advanc$ z 0 ! ma9 l9eage at ! "t ,pliogeomys di$ out4 ,its /ructure does provide clues z to phyletic developm5t t took place 9 ! ma9 l9eage4 ,specializ$ tr5ds 9 ! e>ly phylog5y ( ! ,geomy9i includ$3 developm5t ( rootless1 ev]-gr[+ *eek tee? & an increase 9 hypsodonty2 loss ( ! bicolumn> /ructure ( ! fir/ & second mol>s1 &1 consequ5tly1 ! =mation ( a s+le elliptical column 9 ! f9al /age ( we>2 int]ruption ( ! enamel inve/m5t ( ! mol>i=m tee? & =mation ( ant]ior & po/]ior enamel plates2 & enl>gem5t ( ! masset]ic ridge & fossa4 ,ea* ( ^! tr5ds occurr$ indep5d5tly 9 ! ,?omomy9i1 & ea* is an example ( p>allelism 9 ! phyletic evolution ( ! two l9eages4 ,?ree additional specializations lack+ 9 ! ,?omomy9i are ! groov+ on upp] incisors1 loss ( ant]ior enamel plate 9 l[] mol>s1 & developm5t ( a basitemporal fossa on ! m&ible4 ,evid5tly1 two grooves evolv$ 9 ! ance/ral incisors 9 ! same bisculcate patt]n pres]v$ 9 ,pliogeomys1 ,zygogeomys & ,geomys4 ,! inn]mo/ groove is weakly develop$ 9 ,pliogeomys1 sugge/+ t ?is "* 0 9 an int]m$iate /age ( evolution 9 ! ance/ral l9eage at ! "t t ,pliogeomys split (f4 ,num]\s o!r specializations 9 ! ,geomy9i appe>$ lat]1 b evolv$ 9 ! diff]5t g5]a t div]g$ f ! ance/ral l9eage & are discuss$ sep>ately 9 ! next acc\nt4 ,only two ( ! major features *>act]iz+ ! ,dikkomy9i are reta9$ 9 ! ,geomy9i3 ! ,h-patt]n on ! occlusal surface ( ! m#a & m#b develop$ dur+ ! initial /ages ( we>1 & ! bicolumn> patt]n ( ,m#c4 ,adaptive radiation produc$ ! liv+ g5]a ( ! ,geomy9i 9 ! late ,plioc5e & e>ly ,plei/oc5e 7see ,fig4 #f7 & subsequ5t specialization ( ! ance/ral morphology foll[$4 ,p>allelism 9 ! mol>s ( lat] geomy9es & ! ,entopty*9ae is illu/rat$ by ! lat]al int]ruption ( ! enamel inve/m5t & loss ( enamel plates & by ! omission ( ! ,h-patt]n /age 9 ! fir/ & second mol>s 79 ,pliosaccomys74 ,resemblance ( d5titions 9 c]ta9 /ages ( we> 9 ,pliosaccomys & 9 entopty*9es l$ "s inve/igators1 = in/ance1 ,hibb>d 7#aiec3ceg71 to sugge/ t ,pliosaccomys desc5d$ f "o ( ! less specializ$ entopty*9es1 possibly ,grang]imus b probably ,gregorymys4 ,actually1 ! highly specializ$ upp] & l[] premol>s & ?ird mol>s ( ! entopty*9es rule !m out z ance/ors ( ! lat] geomy9es4 ,! evolution ( entopty*9e-l features 9 ,pliosaccomys is reg>d$ z an example ( it]ation1 a patt]n ( p>allelism 7see ,simpson1 #aiec3bdh-bec7 :]e an allo*ronic & indep5d5t l9eage und]goes ! same evolution>y tr5d t phyletically *>act]iz$ an e>li] l9eage1 usually aft] ! latt] has become ext9ct4 ,9 ?is case1 ! l9eage giv+ rise to ,pliosaccomys pass$ ?r\gh ! same phyletic /ages 9 its evolution 9 ! e>ly ,plioc5e 7& possibly ! late ,mioc5e7 z did ! entopty*9es 9 ! late ,oligoc5e & e>ly ,mioc5e4 ,ano!r p>allelism by it]ation1 occurr+ 9 ! middle & late ,plioc5e 9 bo? ! ,?omomy9i & ,geomy9i1 is ! loss ( enamel f ! lat]al surfaces ( ! *eek tee?1 &1 9 ! ,geomy9i only1 ! ev5tual loss ( ! ant]ior plate 9 ! l[] tee? & ! po/]ior plate 9 ! upp] tee?4 ,bo? features 7 evolv$ m ?an an epo* e>li] 9 ! specializ$ entopty*id g5us ,entopty*us ( ! l[] ,mioc5e4 ,9 ,entopty*us1 only ! po/]ior plate ( ! l[] mol>s & ! ant]ior plate ( ! upp] mol>s rema9$ 9 ! f9al /ages ( attrition1 al?\gh a c5tral enamel fossette1 a remnant ( ! re-entrant fold1 rema9$ ?r\gh\t life4 ,it]ation is also express$ 9 ! subfamily ,geomy9ae by ! developm5t ( groov+ on ! upp] incisor & ! =mation ( ! basitemporal fossa4 ,a %all[ b di/9ct basitemporal fossa occurs betwe5 ! coronoid process & ! ?ird l[] mol> 9 ! g5us ,entopty*us & a sulcat$ upp] incisor1 a s+le %all[ groove usually ne> ! m$ian bord] ( ! too?1 is f\nd 9 ! g5us ,gregorymys ( ! subfamily ,entopty*9ae4 ,bo? features are reg>d$ z advanc$ specializations 9 ! tribe ,geomy9i1 ev5 ?\gh ea* 0 evolv$ 9 ! entopty*9es ( ! ,l[] ,mioc5e4 ,! po/cranial skeleton ( liv+ g5]a ( pocket goph]s1 z befits animals t sp5d mo/ ( _! life )9 und]gr\nd burr[s1 are highly specializ$ = a fossorial life4 ,elem5ts ( ! po/cranial skeleton recov]$ f ,l[] ,mioc5e deposits indicate t ! entopty*9es 7 only semi-fossorial 7see ,cope1 #ahhd3heg2 ,wood1 #aicf3d-e2 ,wilson1 #aidi3aag-aah74 ,"o ( ! basic tr5ds ( ! entopty*9es 0 t[>ds great] fossorial adaptation2 ! skeleton ( ,entopty*us %[s a great] degree ( fossorial adaptation ?an e>li] g5]a ( ! subfamily4 ,!re is no reason to suppose t ! geomy9e g5us ,dikkomys1 :i* liv$ at ! same times z ! entopty*9es1 _h acquir$ any m advanc$ fossorial adaptations ?an _h ! entopty*9es4 ,! mo/ pron\nc$ fossorial adaptations seem to h evolv$ only 9 ! ance/ral l9eage ( ! mod]n geomy9es1 probably 9 ! latt] "p ( ! ,mioc5e & 9 ! e>ly ,plioc5e1 be=e ! mod]n ,?omomy9i & ,geomy9i div]g$4 ,extreme fossorial adaptations 9 h]bivor\s rod5ts1 su* z ^? *>act]i/ic ( ! mod]n pocket goph]s & _! imm$iate ance/ors1 are ?\ght to h evolv$ only 9 response to pron\nc$ arid conditions4 ,! ,entopty*9ae & evid5tly ! e>ly geomy9es liv$ 9 environm5ts t 7 ei!r tropical or temp]ate1 & "u conditions m mesic ?an ,i w\ld consid] necess>y to br+ ab\t selection pressure result+ 9 fossorial specializations4 ,9 late ,oligoc5e & e>ly ,mioc5e1 accord+ to ,axelroad 7#aieh3dcc-eji71 arid conditions did n exi/ 9 ! ,unit$ ,/ates1 & ! only x]ophytic environm5ts 9 ,nor? ,am]ica occurr$ on ! ,c5tral ,plateau ( ,mxico4 ,moreov] 7,axelroad1 loc4 cit471 arid conditions did n develop 9 ! we/]n ,unit$ ,/ates until ! e>ly ,plioc5e4 ,geomyids evid5tly became ext9ct 9 ?is region at ! close ( ! ,middle ,mioc5e1 & none appe> 9 fossil deposits 9 ! we/]n ,unit$ ,/ates until ! late/ ,l[] ,plioc5e 7,cl>5donian74 ,! reappe>ance ( geomyids1 ,pliosaccomys1 9 ! we/]n ,unit$ ,/ates co9cides ) a tr5d t[>d aridity & ! nor?w>d movem5t ( ! ,madro-t]ti>y ge(lora into ! ,great ,bas9 & ,great ,pla9s f its place ( orig9 on ! ,c5tral ,plateau ( ,mxico 7,axelroad1 loc4 cit474 ,lat]1 9 ! middle & lat] ,plioc5e1 ! ,madro-t]ti>y ge(lora gave rise to ! mod]n x]ophytic plants t n[ *>act]ize ! des]t vegetation ( ,nor? ,am]ica4 ,! ,madro-t]ti>y climax does n appe> z a major flora until ! ,mioc5e1 b probably orig9at$ e>li]4 ,accord+ to ,axelroad 7loc4 cit471 ?is x]ophytic flora evolv$ f elem5ts ( ! ,neotropical-t]ti>y ge(lora t became adapt$ to arid conditions t develop$ 9 ! ra9 %ad[ ( ! high m\nta9s flank+ ! ,c5tral ,plateau ( ,mxico4 ,orig9ally1 ! ,madro-t]ti>y flora consi/$ ( small trees1 %rubs1 & grasses4 ,al?\gh "s elem5ts ( ?is flora mov$ nor?w>d 9 ! late ,mioc5e1 ! major "p ( x rema9$ 9 ,mxico until ! e>ly ,plioc5e4 ,9 ! we/]n ,unit$ ,/ates1 m\nta9 =mation increas$ 9 int5sity 9 ! ,plioc5e & cont9u$ on into ! e>ly ,plei/oc5e4 ,z ! m\nta9s became m elevat$1 especially ! ,si]ra ,nevada & ,cascade ranges1 !y block$ ! prevail+ w9ds f ! ,pacific ,ocean & ext5sive aridity develop$ on _! leew>d side4 ,z x]ic conditions became widespread1 ! ,madro-t]ti>y flora successfully occupi$ ! dri] regions ( s\!rn ,cali=nia1 ! ,great ,bas91 & ! we/]n p>ts ( ! ,great ,pla9s4 ,:ile ! ,entopty*9ae probably evolv$ 9 response to ! ,arcto-t]ti>y flora1 ! late ,t]ti>y geomy9es probably evolv$ 9 response to ! ,madro-t]ti>y ge(lora on ! ,c5tral ,plateau ( ,mxico4 ,"s ( ^! e>ly geomy9es1 especially ance/ors ( ! mod]n l9eages1 probably 7 pu%$ s\?w>d by competition ) ! m specializ$ entopty*9es4 ,mo/ geomy9es 7 pu%$ out ( ! nor!rn area ( di/ribution1 except = ,dikkomys t surviv$ 9 association ) ! entopty*ids ?r\gh\t ! e>ly & middle ,mioc5e4 ,dur+ ?is "t1 & probably cont9u+ on into ! late ,mioc5e1 ! geomy9es occurr+ to ! s\? 9 ,mxico became adapt$ to ! arid environm5ts ( ! ,madro-t]ti>y ge(lora4 ,( c\rse1 in=mation is lack+ ab\t climates 9 sev]al p>ts ( ! late ,mioc5e & e>ly ,plioc5e4 ,:5 su* in=mation becomes available x conceivably c\ld modify ! hypo!sis outl9$ imm$iately above4 ,! pr9cipal tr5d ( evolution 9 ^! semi-fossorial rod5ts 0 t[>d m complete fossorial adaptation1 & ! pron\nc$ fossorial features *>act]i/ic ( ! mod]n pocket goph]s 7 p]fect$4 ,?is tr5d cont9u$ 9 response to ! int5se selection pressures 9 ?is arid environm5t4 ,! pr9cipal /ructural *>act]s effect$ 7 9 ! po/cranial anatomy1 especially 9 ! skeletal & muscul> sy/ems4 ,consequ5tly1 x is n surpris+ t 9 skull & d5tition1 ,pliosaccomys diff]s b little f ,dikkomys4 ,!re=e1 mo/ ( ! basic /ructural specializations s f> develop$ = subt]ranean exi/5ce probably _h evolv$ by ! "t geomy9es mov$ back nor? 9 ! e>ly ,plioc5e4 ,bo? mod]n l9eages1 ! tribes ,?omomy9i & ,geomy9i1 h ess5tially ! same fossorial features1 & x seems unlikely t ^! features 7 acquir$ indep5d5tly 9 ! relatively %ort p]iod ( "t available to !m aft] _! div]g5ce2 probably !y 7 inh]it$ f a common ance/or4 ,^! probabilities indicate t ! evolution ( ! fossorial specialization 0 9 ! lat] phyletic developm5t ( ! tribe ,dikkomy9i4 ,plio-,plei/oc5e radiation ( ,geomy9i ,unlike ! l9eage ( ! ,?omomy9i t rema9$ ess5tially rectil9e> ?r\gh out its hi/ory1 ! ,geomy9i 9 ! late ,plioc5e & ! e>ly ,plei/oc5e und]w5t adaptive radiation 9 a degree comp>able to ! e>li] radiation ( ! ,entopty*9ae1 & all ( ! lat] hi/ory ( ! tribe is dom9at$ by ! radiation--! result+ /ructural div]sity4 ,at lea/ f\r l9eages 7 produc$ by ! ,plio-,plei/oc5e radiation 7see ,fig4 #f72 ea* orig9at$ at ess5tially ! same "t 7late ,plioc5e7 presumably f ! same ance/ral /ock4 ,ea* ( ^! l9eages )9 ! ,geomy9i has giv5 rise to "o ( ! f\r mod]n g5]a3 ,zygogeomys1 ,geomys1 ,or?ogeomys1 & ,pappogeomys4 ,illu/ration3 ,,fig4 #f4 ,plio-,plei/oc5e radiation ( ! ,tribe ,geomy9i4 ,morphotype ,! imm$iate1 unkn[n1 ance/or probably liv$ on ! ,c5tral ,plateau ( ,mxico4 ,aft] ! radiation began ! ance/ors ( ,geomys & ,zygogeomys ext5d$ _! ranges nor?w>d4 ,features ( ! hypo!tical morphotype1 t w\ld p]mit d]ivation ( ! mod]n g5]a w\ld include ! foll[+3 7#a7 ,skull g5]aliz$1 nei!r excessively long & n>r[ or %ort & broad2 7#b7 skull smoo?ly r\nd$1 )\t pron\nc$ angul>ity1 rugosity or cre/+ 7sagittal cre/ probably lack+1 ev5 9 old individuals72 7#c7 zygomata sl5d]1 )\t lat]al platelike expansions2 7#d7 ro/rum mod]ately broad2 7#e7 upp] incisors bisulcate1 two grooves 9 patt]n f\nd 9 ,pliogeomys1 ,zygogeomys & ,geomys2 7#f7 lat]al re-entrant angles ( premol>s obtuse2 7#g7 p#d hav+ f\r enamel plates 7"o on ant]ior wall1 "o on po/]ior wall1 & two lat]al plates7 & l[] mol>s hav+ "o enamel plate on ! po/]ior wall ( too? 7ant]ior plate is lack+72 7#h7 ,p#d hav+ f\r enamel plates1 9 same patt]n z describ$ = p#d1 ,m#a hav+ two enamel plates 7"o ant]ior & "o po/]ior71 ,m#b same z ,m#a1 ,m#c hav+ ?ree plates 7"o ant]ior1 two lat]al on sides ( po/]ior loph1 none po/]ior72 7#i7 ,m#c subtriangul> 9 cross-section1 di/9ctly bicolumn>1 two columns m>k$ by %all[ re-entrant folds & connect$ by broad i/hmus2 7#aj7 masset]ic ridge l>ge1 =m+ high cre/ bord]+ masset]ic fossa2 7#aa7 basitemporal fossa %all[2 7#ab7 angul> process ( m&ible %ort1 its lat]al projection b>ely exce$+ t ( zygomatic ar*4 ,specializations 9 ,g5]a ,9 relation to ! primitive morphotype1 increase 9 size1 simplification ( d5tition1 & *anges 9 %ape ( skull are reg>d$ z specializations4 ,consid]able p>allelism betwe5 ! f\r l9eages is se54 ,b ea* l9eage is di/+ui%$ by a comb9ation ( specializ$ features1 & ?ree by a few unique specializations4 ,among tr5ds result+ 9 simplification ( ! d5tition1 r$uction ( enamel on ! po/]ior wall ( ! upp] *eek tee? has occurr$ 9 v>i\s degrees 9 all l9eages ( ! ,geomy9i ev5 to loss ( all enamel on ! po/]ior wall ( ! premol>s & mol>s 9 two g5]a4 ,loss ( "s enamel is m common on ,p#d ?an on ,m#a-b1 & has occurr$ 9 all g5]a 7see ,figs4 #g & #i47 ,9 evolution>y sequ5ce loss ( enamel f ,m#a & ,m#b usually occurs aft]1 b nev] prec$+1 ! r$uction ( enamel on ,p#d4 ,loss ( enamel plates f ! po/]ior face ( ,m#a & ,m#b is associat$ ) ! evolution ( an effici5t ant]otransv]se %e>+ action ( ! tee?4 ,on ! ant]ior wall ( ^? tee? no r$uction ( ! cutt+ blade has be5 obs]v$2 a complete ant]ior plate is reta9$ 9 all liv+ ,geomy9i4 ,pres5ce ( bo? ! po/]ior & ant]ior plates decreases ! effici5cy ( transv]se %e>+1 by provid+ two upp] plates 7ant]ior plate ( "o too? & po/]ior plate ( ! prec$+ too?7 ov] :i* ! l[] cutt+ blade simultane\sly mu/ pass ) ea* movem5t4 ,! advantages ( %e>+ ov] ! m common me*anics ( plan+ are l>gely lo/ unless ! po/]ior plates are elim9at$4 ,also1 none ( ! liv+ ,geomy9i h reta9$ a def9itive po/]ior enamel plate on ,m#c1 ! la/ upp] mol>2 b two well-develop$ lat]al plates1 t ext5d almo/ all ( ! way back to ! po/]ior apex ( ,m#c1 h be5 reta9$1 &1 toge!r function z a po/]ior plate4 ,loss ( ei!r or bo? ( ! lat]al plates ( ,m#c is r>e1 & occurs only 9 old individuals4 ,_! loss 9 ! f9al /ages ( we> may repres5t ! beg9n+ ( a new tr5d 9 ^? species :]e x occurs 7! ca/anops-gr\p ( ! subg5us ,cratogeomys74 ,9 any case1 r$uction ( enamel takes place by transv]se %ort5+ ( ! plate ?r\gh ! complete loss ( enamel on "o end1 ! dim9ution beg9n+ fir/ on ! labial end & proce$+ by progressive atrophy to ! l+ual end ( ! plate4 ,evid5tly1 :5 enamel has be5 elim9at$ f ! labial end ( a plate1 ! rate ( loss decreases m>k$ly1 & ! la/ /ages ( evolution1 t]m9at+ 9 complete loss ( an enamel plate1 occurs m sl[ly4 ,evolution may be arre/$ be=e complete loss has occurr$1 & t "p ( ! enamel t rema9s =ms a %ort1 ve/igial plate re/rict$ to ! l+ual "o-f\r? or "o-?ird ( ! wall4 ,! enamel patt]n ( ! l[] d5tition is ! same 9 all ( ! div]g+ l9eages1 ) no evid5ce ( additional loss ( enamel f t :i* _h already occurr$ 9 _! common ance/or 7see ,figs4 #g & #i74 ,r$uction & loss ( enamel plates began & 0 t]m9at$ 9 ! l[] d5tition be=e r$uction began 9 ! upp] d5tition4 ,o!r d5tal specializations h occurr$ 9 ! %ape ( ! ?ird upp] mol> & 9 ! patt]n ( groov+ 9 ! upp] incisor4 ,unlike ,m#c ( ! ,?omomy9i1 t ( ! ,geomy9i diff]s 9 %ape f ,m#b1 & its enamel inve/m5t diff]s f t ( ,m#b4 ,primitively1 ,m#c 0 probably subtriangul> 9 cross-section1 & ! po/]ior loph evid5tly project$ po/]iorly z a %ort1 rudim5t>y heel t =m$ ! apex ( ! triangle4 ,o!r %apes ( ,m#c are consid]$ to be specializations t h be5 d]iv$ f ! primitive =m4 ,9 addition to ! primitive subtriangul> patt]n1 ! ,m#c ( liv+ ,geomy9i may be suborbicul>1 quadri=m1 elongate1 or obcordate 9 %ape4 ,usually ea* l9eage is *>act]iz$ by only "o patt]n1 b 9 "o g5us 7,pappogeomys7 all patt]ns occur4 ,( ! diff]5t =ms1 ! elongate & obcordate seem to be ! mo/ highly specializ$ deviations f ! triangul>-%ap$ too?4 ,! bicolumn> patt]n is acc5tuat$ 9 ! elongate type 7,fig4 #g;,d1 ,f1 ,h7 by deep lat]al re-entrant folds1 on bo? ! l+ual & labial sides1 & by ! elongation ( ! po/]ior loph into a pron\nc$ heel4 ,tee? hav+ ?is patt]n h be5 illu/rat$ by ,m]riam 7#ahie3gf-hb7 9 ,figures #bg 7#f & #g71 #bh 7c & d71 #cd 7#g ?r\gh #ae71 & #ce 7#h74 ,illu/ration3 ,,fig4 #g4 ,mol>i=m d5titions ( ! ,tribe ,geomy9i4 ,draw+s illu/rat+ enamel patt]ns *>act]i/ic ( ,pliogeomys1 ,zygogeomys1 & ! subg5]a ( ,or?ogeomys 7,or?ogeomys1 ,het]ogeomys & ,macrogeomys74 #e4 ,a4 ,pliogeomys buisi1 ,no4 #biaeg 7,,ummp71 holotype1 ,buis ,ran* 7,upp] ,middle ,plioc5e71 ,beav] ,co41 ,oklahoma4 ,"r l[]1 p#d-m#b 7m#c unkn[n74 ,b & ,c4 ,zygogeomys tri*opus tri*opus1 adult female1 ,no4 #eaiga 7,,fmnh71 ,mt4 ,tanct>o1 #aj1ejj ft41 ,mi*oacn4 ,left upp] 7,b71 ,p#d-,m#c2 "r l[] 7,c71 p#d-m#c4 ,d & ,e4 ,subg5us ,or?ogeomys4 ,or?ogeomys gr&is gu]r]5sis1 adult female1 ,no4 #cihjg 7,,ku71 #a_/b mi4 ,e ,la ,mira1 #cjj ft41 ,mi*oacn4 ,left upp] 7,d71 ,p#d-,m#c2 "r l[] 7,e71 p#d-m#c4 ,f & ,g4 ,subg5us ,het]ogeomys4 ,or?ogeomys hispidus hispidus1 adult female1 ,no4 #bcige 7,,ku71 #d km4 ,w ,tlapacoyan1 #gjj ft41 ,v]acruz4 ,left upp] 7,f71 ,p#d-,m#c2 "r l[] 7,g71 p#d-m#c4 ,h & ,i4 ,subg5us ,macrogeomys4 ,or?ogeomys het]odus c>tago5sis1 adult female1 ,no4 #fjffd 7,,ku71 ,ran*o ,r$&o1 ,volcn ,lroz1 ,prov4 ,san ,jos1 ,co/a ,rica4 ,left upp] 7,h71 ,p#d-,m#c2 "r l[] 7,i71 p#d-m#c4 ,! subcordate =m is *>act]iz$ by pron\nc$ ant]opo/]ior compression1 & ret5tion ( a di/9ct labial re-entrant fold4 ,! po/]ior loph app>5tly has be5 rotat$ 9 su* a way t :at 0 previ\sly its po/]ior bord] n[ lies on ! out] m>g9 ( ! too?2 !re=e1 ! axis ( ! po/]ior loph is /rongly oblique 9 relation to ! ant]opo/]ior be>+ ( ! maxill>y too?-r[1 & ! m$ian enamel plate also has be5 rotat$ & s lies transv]sely across ! po/]ior wall ( ! too?4 ,ow+ to ! rotation ( ! po/]ior loph1 ! apex ( ! obcordate too? is at its l+ual side4 ,! subcordate type is illu/rat$ by ,m]riam 7loc4 cit47 9 ,figures #bg 7#c & #d71 #bh 7a & b71 #cd 7#c & #d71 & #ce 7#e1 #f1 & #g74 ,! suborbicul> & quadri=m types are less specializ$ ?an ! two describ$ above4 ,bo? are *>act]iz$ by r$uction1 (t5 oblit]ation1 ( ! bicolumn> patt]n ( ! subtriangul> ance/ral =m1 especially m>k$ by ! decrease 9 dep? ( ! lat]al re-entrant folds & ! decrease 9 l5g? ( ! po/]ior projection ( ! po/]ior loph4 ,) ^! *anges1 ! too? becomes ess5tially monocolumn>1 its occlusal surface oval 9 outl9e 9 "o & squ>i% 9 %ape 9 ! o!r4 ,occlusal views ( ! suborbicul> =m are pres5t$ by ,m]riam 7loc4 cit47 9 ,figure #cc 7#a1 #e1 #f1 #g1 #aa1 & #ab7 & ! quadri=m too? is depict$ 9 ,figure #bi4 ,groov$ upp] incisors are *>act]i/ic ( ! liv+ ,geomy9i1 b v>iation occurs 9 ! numb] ( grooves1 &1 if only "o groove is pres5t1 its position on ! ant]ior face ( ! too? v>ies4 ,except = ! previ\sly m5tion$ 7p4 #dhj7 abnormal too? hav+ ?ree grooves1 incisors ) no m ?an two grooves are f\nd 9 ^! pocket goph]s1 & ?is numb] ( grooves is tak5 to be primitive4 ,loss ( "o or ! o!r ( ! two grooves ( ! bisulcate patt]n1 !re=e1 is reg>d$ z specialization4 ,h[ev]1 complete loss ( bo? grooves nev] occurs 9 ! ,geomy9i4 ,ea* ( ! f\r major l9eages is *>act]iz$ by "o ( ! ?ree patt]ns ( groov+1 & ! p>ticul> groove-patt]n is rem>kably /able 9 ea* gr\p4 ,%ape ( skull v>ies f doli*ocephalic to platycephalic4 ,! morphology ( ea* has be5 describ$ 9 =ego+ acc\nts4 ,! doli*ocephalic skull is highly specializ$ = plan+1 a gr9d+ action ( ! tee?2 :]eas1 ! platycephalic skull is highly specializ$ = %e>+1 a slic+ action ( ! tee?4 ,( c\rse1 concomitant specializations ( ! d5tition1 z describ$ above1 are closely associat$ ) bo? specializ$ tr5ds 9 ! skull4 ,mo/ k9ds ( liv+ ,geomy9i h g5]aliz$ skulls t %[ no t5d5cy t[>d ei!r ( ! specializ$ conditions4 ,increase 9 size ( body & skull is se5 9 mo/ ,plei/oc5e l9eages ( ! ,geomy9i4 ,judg+ f ! smallness ( ! skull 9 late ,plioc5e species1 repres5t+ ! base ( ?ree ( ^! l9eages1 ! ance/ral species ( ! liv+ assemblage 7 no l>g] ?an ! liv+ species ( ! subg5us ,pappogeomys or ! small] subspecies ( ,geomys burs>ius4 ,! record$ range ( v>iation 9 condylobasal l5g? is #cf4a to #de4e 9 ,pappogeomys bull]i1 includ+ bo? adult males & females4 ,probably ! skulls ( ! ance/ral species 7 n significantly l>g]4 ,maximum dim5sions ( males 9 liv+ species are #gd4e 7subg5us ,cratogeomys7 & #ge4j 7subg5us ,or?ogeomys74 ,^! are m ?an twice ! m9ima obs]v$ 9 ,pappogeomys bull]i4 ,zygogeomys ,?is is ! lea/ specializ$ & mo/ primitive ( ! f\r l9eages1 has a g5]aliz$ type ( skull1 two grooves on ! ant]ior face ( ea* upp] incisor1 an enamel plate on ! po/]ior wall ( ,p#d1 op5 or div]g5t lat]al re-entrant angles on ! premol>s1 & a bicolumn> & elongat$ ,m#c4 ,all ( ^! features are primitive & ess5tially z 9 ! ance/ral morphotype4 ,no o!r mod]n g5us reta9s s mu* ( ! primitive /ructure4 ,phyletic tr5ds 9 ,zygogeomys are n well docum5t$ 9 ! fossil record2 & only a few fossils are kn[n & !y are fragm5t>y z discuss$ be=e4 ,! g5us is repres5t$ 9 ! late ,plioc5e 7,z4 m9or71 middle ,plei/oc5e 7,z4 p]similis71 & ,rec5t 7,z4 tri*opus74 ,! liv+ species is a relict population 9 ! m\nta9s ( ,c5tral ,mxico4 ,judg+ f ! kn[n mat]ial1 ! phyletic tr5ds 9 ! g5us h be5 increase 9 size1 r$uction ( enamel on ! po/]ior face ( ,p#d 7occurr+ only 9 ! liv+ species7 :]e a %ort enamel plate is reta9$ on ! l+ual side ( ! too? 7see ,fig4 #g;,b71 loss ( ! out] f\r? ( ! enamel blade on ! po/]ior wall ( ,m#a & ,m#b 7also occurr+ only 9 ! liv+ species71 developm5t ( a m pron\nc$ heel on ! ,m#c by progressive elongation ( ! po/]ior loph1 r$uction 9 size ( ! jugal & its displacem5t v5trally1 :i* all[s ! maxill>y & squamosal bones to meet along ! dorsal bord] ( ! zygomatic ar*4 ,! la/ specialization is se5 9 at lea/ "o taxon ( ,or?ogeomys 7,or?ogeomys *]riei co/>ic5sis74 ,9 my op9ion1 too mu* weight has be5 giv5 to ?is feature 9 pa/ classifications4 ,r$uction ( enamel 9 ! upp] d5tition evid5tly occurr$ 9 ! late ,plei/oc5e1 s9ce ! po/]ior plates on ! upp] *eek tee? 7 complete 9 specim5s f ! middle ,plei/oc5e 7,z4 p]similis74 ,geomys ,geomys1 slightly m specializ$ ?an ,zygogeomys1 mu/ also be reg>d$ z "o ( ! mo/ primitive ( ! liv+ g5]a4 ,primitive features t h be5 reta9$ are ! g5]aliz$ type ( skull1 ! bisulcate patt]n ( grooves on ! upp] incisor1 & ! ret5tion ( enamel plates on bo? ! ant]ior & po/]ior walls ( ,m#a & ,m#b 7see ,fig4 #i;,a74 ,all ( ^! primitive features are %>$ ) ,zygogeomys4 ,9 addition1 ?ree o!r tr5ds1 or specializations1 9 evolution *>act]ize ! phyletic developm5t ( ,geomys4 ,"o major tr5d is t[>d loss ( ! enamel plate f ! po/]ior wall ( ,p#d4 ,no trace ( enamel rema9s on ! po/]ior wall ( ?is too? 9 late ,plei/oc5e or ,rec5t species ( ,geomys1 & at lea/ "o ( ! e>li] species 7qu9ni7 0 also *>act]iz$ by loss ( ?is enamel plate4 ,secondly1 ,m#c reta9s only a ve/ige ( ! primitive bicolumn> patt]n aft] ! initial /ages ( we>4 ,9 mo/ ,rec5t specim5s1 especially ( ! species ,g4 burs>ius1 ! lat]al re-entrant fold & ! heel ( ,m#c are small1 & ! re-entrant inflection is h>dly evid5t4 ,! lat]al fold is m frequ5tly well-develop$ 9 ,irv+tonian species ?an 9 liv+ species 7,:ite & ,d[ns1 #aifa3ac71 illu/rat+ progressive loss ( ! bicolumn> patt]n 9 ,plei/oc5e evolution4 ,a ?ird tr5d involves ! modification ( ! lat]al folds ( ! premol>s4 ,primitively ! angles ( ^! folds are broadly op5 or div]g5tly ,v-%ap$1 & "s ( ! e>lie/ species ( ,geomys1 = example ,g4 qu9ni1 h reta9$ ?is feature ?r\gh\t life4 ,nev]!less1 ! ma9 tr5d is t[>d progressive compression ( ! folds result+ 9 _! walls be+ m ne>ly p]p5dicul>1 & p>allel1 to ! long axis ( ! too?4 ,obtuse re-entrant angles p]si/ 9 premol>s ( "y individuals ( ,irv+tonian species1 b ! adults are *>act]iz$ by well-compress$ folds1 z 9 ,rec5t species4 ,rema9s ( ,geomys are abundant1 especially f ,plei/oc5e deposits ( ! ,great ,pla9s1 b 9 mo/ in/ances specific assignm5t is difficult or impossible s9ce only isolat$ tee? or fragm5ts ( skulls h be5 pres]v$4 ,e/imates ( phyletic relation%ips ( ! kn[n species ( ,geomys are depict$ 9 ,figure #h2 ^? e/imates are useful 9 discuss+ ! phyletic developm5t ( ! g5us4 ,"o ( ! e>lie/ kn[n species1 ,geomys qu9ni1 ranges f ,upp] ,plioc5e to ! lat] /ages ( ! ,l[] ,plei/oc5e 7,aftonian int]glacial deposits74 ,! d5tition ( ,g4 qu9ni is ess5tially ! same z 9 ! liv+ species except t op5 lat]al re-entrant angles are reta9$ 9 ! premol>s4 ,geomys pa5eburs>ius1 also ( ! e>ly ,plei/oc5e1 is a small] species & seems to be m directly 9 ! l9e ( evolution ( ! mod]n species4 ,z yet unnam$ small] species ( ,geomys f ! ,rexroad fauna 7late ,plioc5e7 & ,saund]s fauna 7late/ ,aftonian7 may also be on ! ma9 l9e ( evolution4 ,surpris+ly1 ,geomys tob95sis & ,geomys g>banii ( lat] ,irv+tonian prov9cial age are less specializ$ ?an ei!r ,geomys qu9ni or ,geomys pa5eburs>ius4 ,x is likely t ,g4 tob95sis & ! unnam$ species f ! ,dixon are clos] to ! ma9 l9e ( desc5t ?an ,g4 pa5eburs>ius sugge/+ t ! direct ance/ral l9eage ( ! liv+ species ( ,geomys 0 m cons]vative & less specializ$ ?an ,geomys pa5eburs>ius ( ! ,l[] ,plei/oc5e4 ,geomys qu9ni & ,g4 pa5eburs>ius seem to h acquir$ specializ$ d5tal features 9 ! e>ly ,plei/oc5e4 ,geomys qu9ni 0 successful on ! ,great ,pla9s1 & p]si/$ into ! late ,blancan4 ,! ma9 l9e may be repres5t$ 9 ! e>ly ,plei/oc5e by ,geomys pa5eburs>ius f ! ,hancock =mation ( ! ,texas ,trans-,pecos4 ,! /ructure ( ,g4 pa5eburs>ius indicates t x is 9 or close to ! ma9 l9e ( desc5t1 & probably evolv$ f "o ( ! m primitive late ,plioc5e species ( ,geomys f ! ,rexroad fauna4 ,illu/ration3 ,,fig4 #h4 ,t5tative arrangem5t ( species ( ! g5us ,geomys1 depict+ phylog5etic tr5ds & probable relation%ips )9 ! g5us4 ,isolat$ tee?1 to :i* ! "n ,geomys bisulcatus probably applies1 f ,ill9oian deposits on ! ,great ,pla9s1 %[ t ! d5tition *>act]i/ic ( ! liv+ ,geomys _h be5 develop$ by t "t4 ,actually1 ! ,ill9oian mat]ial is too fragm5t>y to %[ cle>ly its taxonomic or phyletic aff9ities ) ! species ( ! lat] ,plei/oc5e4 ,ev5 s1 ! two ma9 /ocks ( liv+ ,geomys1 ,g4 burs>ius & ,g4 p9etis1 _h c]ta9ly be5 diff]5tiat$ by ,sangamon "t4 ,! o!r liv+ species evid5tly evolv$ f "o or ! o!r ( ^! two /ocks 9 a p]iod ( isolation f ! ma9 population1 probably 9 ei!r ! ,wiscons9 or po/-,wiscons94 ,= example1 ,geomys ar5>ius cle>ly diff]5tiat$ f populations ( ,geomys burs>ius t 7 isolat$ by ! ea/w>d retreat ( ! ma9 population f ! s\?we/]n ,unit$ ,/ates z t region became m arid 9 ! po/-,wiscons94 ,9 review1 x seems t ! ,rec5t species1 repres5t$ basically by burs>ius & p9etis1 evolv$ f ,ill9oian species 7,geomys bisulcatus871 :i* desc5d$ 9 turn f ! m primitive species ( ! e>ly ,plei/oc5e1 possibly ,geomys pa5eburs>ius or possibly f desc5dants ( ! ,saund]s species4 ,actually ! ,saund]s species may prove to be ,geomys pa5eburs>ius4 ,at any rate1 ?ree tr5ds t took place dur+ ! ,plei/oc5e /age ( evolution1 9 ! direction ( ! mod]n species1 7 an increase 9 size1 progressive loss ( ! po/]ior enamel plate on ,p#d1 & a decrease 9 ! v]tical dep? ( ! enamel cap z a result ( :i* ! d5t9e is rea*$ 9 ! initial phases ( attrition on ! too? ( a juv5ile4 ,geomys g>banii1 occurr+ at ! p]iph]y ( ! range ( ! g5us1 is reg>d$ z a /]ile (f%oot ( ! primitive tob95sis-l9e ( evolution4 ,or?ogeomys ,?is is "o ( ! m specializ$ g5]a ( ! ,geomy9i4 ,save = "o record 9 ! late ,plei/oc5e 7,or?ogeomys on]osus71 !re is no fossil hi/ory ( ! g5us ^u :i* to recon/ruct its phylog5y2 !re=e1 its phyletic developm5t mu/ be e/imat$ by comp>+ x & ! primitive morphotype ( ! tribe4 ,results ( t comp>ison sugge/ t ,or?ogeomys has clos] aff9ities ) ,zygogeomys ?an ) any ( ! o!r g5]a1 & t ,or?ogeomys may h orig9at$ 9 an e>ly di*otomy ( primitive ,zygogeomys /ock in/ead ( desc5d+ f ! ance/ral /ock ( ! tribe4 ,except = ! unisulcate incisors & ! long] po/]ior loph on ! ?ird upp] mol>s1 ! tee? ( ! two g5]a d n diff] significantly4 ,z 9 ,zygogeomys1 ! enamel blade on ! po/]ior wall ( ,p#d has be5 r$uc$ to a %ort plate re/rict$ to ! l+ual ?ird ( ! too? 7see ,fig4 #g;,f & ,h74 ,9 ,or?ogeomys1 ! tr5d 9 r$uction ( enamel is c>ri$ to its extreme only 9 ! subg5us ,or?ogeomys1 :]e ?is plate has be5 completely lo/ 9 mo/ taxa 7see ,fig4 #g;,d74 ,! mo/ significant tr5ds 9 ,or?ogeomys1 & ! pr9cipal basis = recogniz+ ! g5us1 are ! doli*ocephalic specializations ( ! skull1 z describ$ else:]e1 & ! adaptive traits t h equipp$ ! g5us = liv+ 9 tropical environm5ts4 ,! doli*ocephalic features are m %>ply def9$ 9 ! subg5]a ,or?ogeomys & ,macrogeomys1 & are less develop$ 9 ! subg5us ,het]ogeomys4 ,aside f ! g5]al doli*ocephalic specializations1 tr5ds 9 ,or?ogeomys include3 ,increase 9 size2 loss ( ! m$ian "o ( ! two grooves on ! ant]ior face ( ! upp] incisor 9 ! ance/ral /ock2 increase 9 ! ant]opo/]ior l5g? ( ea* ( ! *eek tee?1 z well z ! a=em5tion$ elongation ( ! po/]ior loph ( ,m#c2 compression ( ! lat]al angles ( ! premol>s2 & ! rem>kable increase 9 ! size ( ! ro/rum4 ,pappogeomys ,! g5us ,pappogeomys1 z x is conceiv$ ( 9 ?is /udy1 is compris$ ( two subg5]a2 "o1 ,pappogeomys1 is g5]aliz$ & primitive1 & ! o!r1 ,cratogeomys1 is specializ$1 & includes ! mo/ highly specializ$ ( ! mod]n pocket goph]s4 ,! subg5us ,pappogeomys is reg>d$ z ! ance/ral l9eage1 & ! subg5us ,cratogeomys is reg>d$ z an e>ly (f%oot1 probably 9 ! e>ly ,plei/oc5e1 t became progressively m specializ$ 9 ! c\rse ( its subsequ5t evolution4 ,9 ! same p]iod ( "t1 ! subg5us ,pappogeomys *ang$ little4 ,x is kn[n only f late ,plioc5e fragm5ts & f ! liv+ species4 ,! ance/ral morphotype is pres]v$ 9 ,pappogeomys4 ,primitive *>act]s are3 7#a7 ,small size2 7#b7 skull g5]aliz$ & smoo?ly r\nd$2 7#c7 temporal ridges sep>ate 7n unit+ into a sagittal cre/72 7#d7 enamel plates reta9$ on bo? ant]ior & po/]ior walls ( ,m#a & ,m#b2 7#e7 ,m#c bilophate1 its po/]ior loph %ort4 ,basic specializations are few & include loss ( ! inn] groove f ! ant]ior face ( ! upp] incisor2 ant]opo/]ior compression ( ! lat]al re-entrant folds ( ! premol>s2 & loss ( enamel f ! po/]ior wall ( ,p#d4 ,all ?ree features h be5 p]petuat$ 9 ! advanc$ subg5us ,cratogeomys1 sugge/+ t !y 7 already develop$ 9 ! e>ly evolution ( ! subg5us ,pappogeomys be=e ,cratogeomys div]g$4 ,agreem5t ) ,geomys is demon/rat$ by ! lack ( enamel on ! po/]ior wall ( ,p#d 7see ,fig4 #i7 & by ret5tion ( ! po/]ior enamel plate on ,m#a & ,m#b4 ,9 ,pappogeomys 7,pappogeomys7 alcorni ! enamel f ! po/]ior face ( ,m#a has be5 lo/ f all b ! l+ual f\r? or s ( ! po/]ior wall 7,fig4 #i;,e74 ,r$uction ( enamel 9 ,m#a provides an example ( p>allelism ) ! m advanc$ subg5us ,cratogeomys1 discuss$ bel[4 ,!re is no record z yet ( ! e>ly evolution ( ! subg5us ,cratogeomys4 ,! features t *>act]ize ! subg5us 7 already well develop$ 9 ! fir/ kn[n fossils :i* are f ,wiscons9 deposits ( ! late ,plei/oc5e4 ,cratogeomys is n a homog5\s assemblage2 in/ead x is compos$ ( two gr\ps ( liv+ species1 ! g5]aliz$ ca/anops gr\p & ! specializ$ gymnurus gr\p4 ,! ca/anops gr\p may be survivors ( ! ance/ral l9eage t div]g$ 9 two diff]5t /ages 9 ! phyletic developm5t ( ! ma9 l9e4 ,ev5 s1 ! ca/anops gr\p has acquir$ its peculi> specializations4 ,inde$1 ,p4 m]riami ( ! ca/anops gr\p diff]s f ! hypo!tical /em m ?an does ,p4 ca/anops4 ,judg+ f ! /ructure ( ! liv+ species ( ! subg5us ,cratogeomys & f ! primitive subg5us ,pappogeomys1 ! subg5us ,cratogeomys featur$ five major tr5ds3 7#a7 ,increase 9 size2 7#b7 =mation ( sagittal cre/ by union ( ! temporal impressions2 7#c7 increase 9 rugosity & angul>ity ( ! skull2 7#d7 progressive developm5t ( platycephalic specializations1 includ+ ! elongation ( ! angul> process ( ! m&ible2 7#e7 complete loss ( enamel plates f ! po/]ior wall ( ,m#a & ,m#b4 ,ea* tr5d is ?\ght to be adaptive4 ,illu/ration3 ,,fig4 #i4 ,mol>i=m d5titions ( ! ,tribe ,geomy9i4 ,draw+s illu/rat+ enamel patt]ns *>act]i/ic ( ,geomys & ,pappogeomys 7includ+ ! subg5]a ,pappogeomys & ,cratogeomys74 #e4 ,a & ,b4 ,geomys burs>ius burs>ius1 adult female1 ,no4 #dfbge 7,,ku71 ,elk ,riv]1 ,%]borne ,co41 ,m9nesota4 ,left upp] 7,a71 ,p#d-,m#c2 "r l[] 7,b71 p#d-m#c4 ,c & ,d4 ,subg5us ,pappogeomys4 ,pappogeomys bull]i alb9asus1 adult female1 ,no4 #cajjb 7,,ku71 ,w side ,la ,v5ta1 #ac mi4 ,w & #d mi4 ,n ,guadalaj>a1 ,jalisco4 ,left upp] 7,c71 ,p#d-,m#c2 "r l[] 7,d71 p#d-m#c4 ,e & ,f4 ,subg5us ,pappogeomys4 ,pappogeomys alcorni1 adult female1 ,no4 #cajea 7,,ku71 holotype1 #d mi4 ,w ,mazamitla1 #ffjj ft41 ,jalisco4 ,left upp] 7,e71 ,p#d-,m#c2 "r l[] 7,f71 p#d-m#c4 ,g & ,h4 ,subg5us ,cratogeomys4 ,pappogeomys gymnurus tellus1 adult female1 ,no4 #cajea 7,,ku71 #a mi4 ,,ne ,tala1 #ddjj ft41 ,jalisco4 ,left upp] 7,g71 ,p#d-,m#c2 "r l[] 7,h71 p#d-m#c4 ,loss ( enamel is a tr5d common to all liv+ g5]a ( ! tribe ,geomy9i1 b ! greate/ loss has occurr$ 9 ,cratogeomys4 ,x has lo/ ! plates on ! po/]ior walls ( ,m#a & ,m#b 7,fig4 #i;,g74 ,if ! lat]al plates ( ,m#c are consid]$ z "o functional plate & ! lat]al plates on ei!r side ( ,p#d toge!r z two transv]se plates1 !n1 ! transv]se cutt+ blades 9 ,cratogeomys numb] sev5 9 ! upp] & sev5 9 ! l[] *eek tee? comp>$ ) #aj 9 ! upp] & sev5 9 ! l[] 9 ! primitive morphotype4 ,inde$1 9 "s species ( ! subg5us1 "o or bo? ( ! lat]al plates on ,m#c is also lo/1 usually 9 old age1 result+ 9 ev5 great] r$uction ( enamel4 ,loss ( enamel f ! po/]ior walls ( ! upp] mol>s may be associat$ ) *anges 9 ! me*anics ( ma/ication f ant]opo/]ior plan+ to ant]otransv]se %e>+1 z discuss$ else:]e4 ,m]riam 7#ahie3ie-if7 argues conv9c+ly t ! po/]ior cutt+ blades ( ! upp] mol>s w\ld h9d] effici5t %e>+ action ( ! tee?2 h5ce1 selection w\ld favor _! r$uction & ev5tual loss4 ,*anges 9 ! %ape ( ! skull also seem to be correlat$ ) ! %ift f a plan+ to a %e>+ type ( ma/ication4 ,m effici5t %e>+ action1 :i* dep5ds ^u lat]al movem5t ( ! jaw1 c be develop$ if ! functional muscles ins]t f>!r lat]ally ?an is possible 9 ! g5]aliz$ type ( skull4 ,!re=e1 platycephalic specializations involv$ lat]al expansion ( ! bra9case & m&ible4 ,pron\nc$ lat]al expansion has be5 develop$ only 9 ! gymnurus gr\p ( species1 sugge/+ t ! d5tal specializations evolv$ e>li] 9 ! evolution ( ! subg5us ?an did ! platycephalic specializations ( ! skull1 & t ! ca/anops gr\p sep>at$ f ! gymnurus gr\p be=e ! common ance/or _h develop$ ! m extreme tr5ds 9 platycephaly4 ,x is int]e/+ to note t ! subtriangul> ,m#c 7,fig4 #i;,g7 po/ulat$ = ! ance/ral morphotype & t *>act]izes ! subg5us ,pappogeomys is reta9$ also 9 ! gymnurus gr\p4 ,,lit]ature ,,cit$ ,,al/on1 ,e4 ,r4 #ahgf4 ,on ! classification ( ! ord] ,glires4 ,proc4 ,zool4 ,soc4 ,london1 #ahgf3fa-ih1 #a pl41 ,june4 ,,alv>ez1 ,t4 #aifd4 ,nota sobre re/os oseos de mamif]os del ,reci5te1 encontrados c]ca de ,tepeapulco1 ,hidalgo1 ,mexico4 ,publ4 ,in/4 ,nac4 ,antro1 e ,hi/41 #ae3a-ae4 #aife4 ,catlago ,paleoma/ozoolgico ,mexicano4 ,publ4 ,in/4 ,nac4 ,antro1 e ,hi/41 #ag3a-gj4 ,,axl]od1 ,d4 ,i4 #aiej4 ,/udies 9 late ,t]ti>y paleobotany4 ,c>negie ,in/4 ,wa%+ton ,publ41 #eij3a-cbb4 #aieh4 ,evolution ( ! ,madro-t]ti>y ge(lora4 ,bot4 ,rev41 #bd3dcc-eji4 ,,bad]1 ,r4 ,s41 & ,,te*t]1 ,d4 #aiei4 ,a li/ & bibliography ( ! fossil mammals ( ,ill9ois4 ,nat4 ,hi/4 ,misc41 ,*icago ,acad4 ,sci41 #agb3a-h1 ,octob] #cj4 ,,baird1 ,s4 ,f4 #aheh4 ,mammals4 ,"p ,i4 ,g5]al report ^u ! zoology ( ! sev]al ,pacific railroad r\tes4 ,repts41 explorations & surveys = a railroad r\te f ! ,mississippi ,riv] to ! ,pacific ,ocean4 ,wa%+ton1 ,d4 ,c41 vol4 #h1 pp4 xlviii #geg1 #ce figs41 #dc pls41 ,july #ad4 ,,b>b\r1 ,h41 & ,,s*ultz1 ,c4 ,b4 #aicg4 ,an e>ly ,plei/oc5e fauna f ,nebraska4 ,am]4 ,mus4 ,nat4 ,hi/4 ,novit41 #idb3a-aj1 ,septemb] #aj4 ,,b]ry1 ,e4 ,w4 #aicg4 ,t]ti>y floras ( ,nor? ,am]ica4 ,bot4 ,rev41 #c3ca-df4 ,,black1 ,c4 ,c4 #aifa4 ,rod5ts & lagomorphs f ! ,mioc5e ,=t ,logan & ,deep ,riv] ,=mations ( ,montana4 ,po/illa1 ,yale ,peabody ,museum1 #dh3a-bj1 #f figs41 ,janu>y #af4 ,,br&t1 ,j4 ,f4 #ahee4 ,beitrge zur mh]n ,k5ntiss d] ,suge?i]e ,russl&s4 ,acad4 ,imp4 des ,sci5ces ,/4 ,pet]sburg1 #g3gi-ccf1 #aa pls4 ,,br[n1 ,b4 #aijh4 ,! ,con>d fissure1 a ,plei/oc5e bone deposit 9 nor!rn ,arkansas ) description ( two g5]a #bj new species ( mammals4 ,mem4 ,am]4 ,mus4 ,nat4 ,hi/41 #i3aeg-bjh1 #b pls41 #c figs4 #aiab4 ,bra*yo/racon1 a new g5us ( glyptodont f ,mexico4 ,bull4 ,am]4 ,mus4 ,nat4 ,hi/41 #ca3afg-agg1 ,augu/ #b4 ,,*aney1 ,r4 ,w4 #aidg4 ,t]ti>y c5t]s & migration r\tes4 ,ecol4 ,monog41 #ag3aci-adh4 ,,cook1 ,h4 ,j41 & ,,cook1 ,m4 ,c4 #aicc4 ,faunal li/s ( ! ,t]ti>y ,v]tebrata ( ,nebraska & adjac5t areas4 ,nebraska ,geol4 ,surv41 ,pap] ,no4 #e3di4 ,,cope1 ,e4 ,d4 #ahgh4 ,description ( new ext9ct ,v]tebrata f ! upp] ,t]ti>y & ,dakota =mations4 ,bull4 ,u4 ,s4 ,geol4 & ,geog4 ,surv41 #d3cgi-cif4 #ahhd4 ,! ,:ite ,riv] & ,john ,day faunae1 pp4 #gei-ajjb1 pl4 #fd1 figs4 #a-i4 ,9 ,! ,v]tebrata ( ! ,t]ti>y =mations ( ! we/4 ,book ,i4 ,"p second4 ,rept4 ,u4 ,s4 ,geol4 ,surv4 ,t]r4 7,f4 ,v4 ,hayd571 vol4 #c4 #ahhi4 ,! v]tebrate fauna ( ! ,equus b$s4 ,am]4 ,nat41 #bc3afj-afe4 ,,c\es1 ,e4 #ahgg4 ,monographs ( ,nor? ,am]ican ,rod5tia4 ,no4 #h1 ,saccomy9ae1 pp4 #dhc-edb1 & ,no4 #aj1 ,geomy9ae1 pp4 #fja-fbi1 pl4 #g1 ,augu/4 ,,dalque/1 ,w4 ,w4 #aifb;a4 ,a record ( ! giant bison 7,bison latifrons7 f ,cooke ,c\nty1 ,texas4 ,texas ,j\r4 ,sci41 #ac3da-dd1 ,m>*4 #aifb;b4 ,! ,good ,creek ,=mation ( ,texas1 & its fauna4 ,j\r4 ,paleont41 #cf3efh-ehb4 #aifd4 ,a new ,plei/oc5e local fauna f ,motley ,c\nty1 ,texas4 ,trans4 ,kansas ,acad4 ,sci41 #fg3dii-eje1 #d figs41 ,decemb] #aa4 #aife4 ,new ,plei/oc5e ,=mation & local fauna f ,h>deman ,c\nty1 ,texas4 ,j\r4 ,paleont41 #ci3fc-gb1 #b figs41 ,janu>y4 ,,dice1 ,l4 ,r4 #aibe4 ,rod5ts & lagomorphs ( ! ,ran*o ,la ,brea ,deposits4 ,c>negie ,in/4 ,wa%+ton ,publ41 #cdi3aai-acj4 ,,davis1 ,w4 ,b4 #aicg4 ,v>iations 9 ,t[ns5d pocket goph]s4 ,j\r4 ,mamm41 #ah3ade-aeh1 ,may #ab4 ,,ell]man1 ,j4 ,r4 #aidj4 ,! families & g5]a ( liv+ rod5ts4 ,vol4 ,i4 ,rod5ts o!r ?an ,muridae4 ,briti% ,museum 7,nat4 ,hi/471 ,london1 pp4 xxvi #fhi1 #ahi figs41 ,june #h4 ,,elliott1 ,d4 ,g4 #aijc4 ,a li/ ( mammals obta9$ by ,edmund ,hell] f ! coa/ region ( nor!rn ,cali=nia & ,oregon4 ,field ,columb4 ,mus4 ,publ41 #gf1 zool4 s]4 vol4 #c7aa73age-aig1 ,july #be4 ,,elftman1 ,h4 ,o4 #aica4 ,plei/oc5e mammals ( ,fossil ,lake1 ,oregon1 ,am]4 ,mus4 ,novit41 #dha3a-ba1 #aj figs41 ,july #ad4 ,,franz51 ,d4 ,s4 #aidg4 ,! pocket goph]1 ,geomys qu9ni ,mc,grew1 9 ! ,rexroad fauna1 ,blancan age1 ( s\?we/]n ,kansas4 ,trans4 ,kansas ,acad4 ,sci41 #ej3ee-ei4 ,,freud5b]g1 ,w4 #aiba4 ,geologie von ,mexiko4 ,b]l91 pp4 viii #bcb4 ,,galbrea?1 ,e4 ,c4 #ahdh4 ,an additional specim5 ( ! rod5t ,dikkomys f ! ,mioc5e ( ,nebraska4 ,trans4 ,kansas ,acad4 ,sci41 #ea3caf-cag4 ,,gaz91 ,c4 ,l4 #aice4 ,annotat$ li/ ( ,plei/oc5e ,mammalia f ,am]ican ,falls1 ,idaho1 ,j\r4 ,wa%+ton ,acad4 ,sci41 #be3big-cjb4 #aidb4 ,! late ,c5ozoic v]tebrate fauna f ! ,san ,p$ro ,valley1 ,arizona4 ,proc4 ,u4 ,s4 ,nat4 ,mus41 #ib7caee73dge3eah1 #b pls41 #i figs4 ,,g]vais1 ,p4 #ahdi4 ,rongeurs4 ,9 ,dictionnaire univ]sel d'hi/orie naturelle1 ,dirig p> ,m ,*4 d',orbigny1 ,p>is1 ,m4 ,m4 ,r5>d1 ,m>t9et et ,cie1 vol4 #aa3aih-bjd4 ,,gidley1 ,j4 ,w4 #aibb4 ,prelim9>y report on fossil v]tebrates ( ! ,san ,p$ro ,valley1 ,arizona1 ) descriptions ( new species ( ,rod5tia & ,lagomorpha4 ,u4 ,s4 ,geol4 ,surv4 ,pr(4 ,pap]s1 #aca3aai-acj1 pls4 #cd & #ce4 ,,gidley1 ,j4 ,w41 & ,,gaz91 ,c4 ,l4 #aicc4 ,new ,mammalia 9 ! ,plei/oc5e fauna f ,cumb]l& ,cave4 ,j\r4 ,mamm41 #ad3cdc-ceg1 #i figs4 ,,gill1 ,t4 ,h4 #ahgb4 ,arrangem5t ( ! families ( mammals ) analytical tables4 ,smi?sonian ,misc4 ,coll41 #aa1 art4 #a1 pp4 vi #ih4 ,,gilmore1 ,r4 ,m4 #aidg4 ,report on a collection ( mammal bones f ar*eologic cave-sites 9 ,coahuila1 ,mexico4 ,j\r4 ,mamm41 #ch3adg-afe1 ,june #a4 ,,gray1 ,j4 ,e4 #ahfh4 ,synopsis ( ! species ,saccomy9ae or p\*$ mice 9 ! collection ( ! ,briti% ,museum4 ,proc4 ,zool4 ,soc4 ,london1 #ahfh3aii-bjf1 ,may4 ,,gre51 ,m4 #aief4 ,! l[] ,plioc5e ,ogallala-,wolf ,creek v]tebrate fauna1 ,s\? ,dakota4 ,j\r4 ,paleo41 #cj7a73adf-afi1 #ab figs41 ,janu>y4 ,,gut1 ,h4 ,j41 & ,,ray1 ,c4 ,e4 #aifc4 ,! ,plei/oc5e v]tebrate fauna ( ,r$dick1 ,florida4 ,qu>t4 ,j\r4 ,florida ,acad4 ,sci41 #bf3cae-cbh4 ,,hall1 ,e4 ,r41 & ,,kelson1 ,k4 ,r4 #aiei4 ,! mammals ( ,nor? ,am]ica4 #b vols41 xxx #ajhc pp41 #eec figs41 #ejj maps1 ,m>* #ca4 ,,h>ris1 ,a4 ,h41 & ,,f9dley1 ,j4 ,s4 #aifd4 ,plei/oc5e--,rec5t fauna ( ! ,isleta ,caves1 ,b]nalillo ,c\nty1 ,new ,mexico4 ,am]4 ,j\r4 ,sci41 #bfb3aad-abj1 ,janu>y4 ,,hay1 ,o4 ,p4 #aibj4 ,description ( "s ,plei/oc5e v]tebrates f\nd 9 ! ,unit$ ,/ates4 ,proc4 ,u4 ,s4 ,nat4 ,mus41 #eg3hc-adf1 #h pls41 #d figs4 #aiba4 ,description ( species ( ,plei/oc5e v]tebrate types ( specim5s ( mo/ ( :i* are pres]v$ 9 ! ,u4 ,s4 ,national ,museum4 ,proc4 ,u4 ,s4 ,nat4 ,mus41 #ei3eii-fdb4 #aibc4 ,! ,plei/oc5e ( ,nor? ,am]ica & its v]tebrat$ animals f ! /ates ea/ ( ! ,mississippi ,riv] & f ! ,canadian prov9ces ea/ ( longitude #ie4 ,c>negie ,in/4 ,wa%+ton1 ,publ4 #cbb3 #a-dii1 ,febru>y #bd4 #aibd4 ,! ,plei/oc5e ( ! middle region ( ,nor? ,am]ica & its v]tebrat$ animals4 ,c>negie ,in/4 ,wa%+ton1 ,publ4 #cbb;,a3#a-cdf4 #aibg4 ,! ,plei/oc5e ( ! we/]n region ( ,nor? ,am]ica & its v]tebrate animals4 ,c>negie ,in/4 ,wa%41 ,publ4 #cbb;,b1 pp4 v #cdf1 #ab pls41 #ba maps1 #aj text figs4 ,,hibb>d1 ,c4 ,w4 #aich4 ,an ,upp] ,plioc5e fauna f ,meade ,c\nty1 ,kansas4 ,trans4 ,kansas ,acad4 ,sci41 #dj3bci-bfe1 #e pls41 #b figs4 #aida;a4 ,! ,bor*]s fauna1 a new ,plei/oc5e int]glacial fauna f ,meade ,c\nty1 ,kansas4 ,bull4 ,/ate ,geol4 ,surv4 ,kansas1 #ch3aig-bbj1 #b pls41 ,july #ad4 #aida;b4 ,mammals ( ! ,rexroad ,fauna f ! ,upp] ,plioc5e ( s\?we/]n ,kansas4 ,trans4 ,kansas ,acad4 ,sci41 #dd3bfe-cac1 #d pls4 #aidc4 ,! ,rezabek fauna1 a new ,plei/oc5e fauna f ,l9coln ,c\nty1 ,kansas4 ,univ4 ,kansas ,sci4 ,bull41 #bi3bce-bdg1 ,octob] #ae4 #aidd4 ,/ratigraphy & v]tebrate paleontology ( ,plei/oc5e deposits ( s\?we/]n ,kansas4 ,geol4 ,soc4 ,am]4 ,bull41 #ee3gjg-ged1 #c pls41 #bj figs4 #aiej4 ,mammals ( ! ,rexroad ,=mation f ,fox ,canyon1 ,meade ,c\nty1 ,kansas4 ,univ4 ,mi*igan ,paleo4 ,contrib41 #h7f73aac-aib1 #e pls41 #bc figs4 #aiea4 ,?omomys talpoides 7,ri*>dson7 f a late ,plei/oc5e deposit 9 ,kansas4 ,j\r4 ,mamm41 #cb3bbi-bcj4 #aieb4 ,v]tebrate fossils f late ,c5ozoic deposits ( c5tral ,kansas4 ,univ4 ,kans4 ,paleont4 ,contrib41 ,v]tebrata1 #b3a-ad1 ,m>* #bj4 #aiec4 ,! ,saw ,rock ,canyon fauna & its /ratigraphic significance4 ,pap]s ,mi*igan ,acad4 ,sci41 ,arts1 & ,lett]s1 #ch3chg-daa4 #aied4 ,a new ,plioc5e v]tebrate fauna f ,oklahoma4 ,pap]s ,mi*igan ,acad4 ,sci41 ,arts1 ,lett]s1 #ci3cci-cei4 #aiee;a4 ,plei/oc5e v]tebrates f ! upp] ,b]c]ra 7,b]c]ra ,sup]ior7 ,=mation1 valley ( ,tecquixquiac1 ,mexico1 ) notes on o!r ,plei/oc5e =ms4 ,contribution f ,mus4 ,paleo41 ,univ4 ,mi*igan1 #ab3dg-if1 #i pls41 #e figs41 ,febru>y #ah4 #aiee;b4 ,! ,j+lebob int]glacial 7,sangamon87 fauna f ,kansas & its climatic significance4 ,contrib4 ,mus4 ,paleo41 ,univ4 ,mi*igan1 #ab3 #agi-bbh1 #b pls41 #h figs41 ,septemb] #a4 #aief4 ,v]tebrate fossils f ! ,meade ,=mation ( s\?we/]n ,kansas4 ,pap]s ,mi*igan ,acad4 ,sci41 ,arts1 & ,lett]s1 #da3ade-bjj4 #aieh4 ,summ>y ( ,nor? ,am]ican ,plie/oc5e mammalian local faunas4 ,pap]s ( ,mi*igan ,acad4 ,sci41 ,arts1 & ,lett]s1 #dc3a-cb4 #aifc4 ,a late ,ill9oian fauna f s\?we/]n ,kansas & its climatic significance4 ,pap]s ,mi*igan ,acad4 ,sci41 ,arts & ,lett]s1 #dh3ahg-bba1 #h figs4 ,,hibb>d1 ,c4 ,w41 & ,,ke5mon1 ,k4 ,a4 #aiej4 ,new evid5ce ( ! ,l[] ,mioc5e age ( ! ,blacktail ,de] ,creek ,=mation 9 ,montana4 ,contrib4 ,univ4 ,mi*igan ,mus4 ,paleo41 #h3aic-bjd1 #c figs41 #a map1 ,july #bh4 ,,hibb>d1 ,c4 ,w41 & ,,moos]1 ,o4 #aifc4 ,a porcup9e f ! ,plei/oc5e ( ,aguascali5tes1 ,mexico4 ,contrib4 ,mus4 ,paleo4 ,univ4 ,mi*igan1 #ah3bde-bej1 ,novemb] #bb4 ,,hibb>d1 ,c4 ,w41 ,,ray1 ,d4 ,e41 ,,savage1 ,d4 ,e41 ,,taylor1 ,d4 ,w41 ,,guilday1 ,g4 ,e4 #aife4 ,quat]n>y mammals ( ,nor? ,am]ica4 ,9 ,quat]n>y ( ! ,unit$ ,/ates4 ,eds4 ,h4 ,e4 ,wright1 ,jr41 & ,d4 ,g4 ,frey4 ,pr9ceton ,univ4 ,press1 ,pr9ceton1 pp4 x #ibb4 ,,hibb>d1 ,c4 ,w41 & ,,riggs1 ,e4 #aidi4 ,upp] ,plioc5e v]tebrates f ,keef ,canyon1 ,meade ,c\nty1 ,kansas4 ,geol4 ,soc4 ,am]4 ,bull41 #fj7e73hbi-hfj1 #aa figs41 #e pls4 ,,hibb>d1 ,c4 ,w41 & ,,taylor1 ,d4 ,w4 #aifj4 ,two late ,plei/oc5e faunas f s\?we/]n ,kansas4 ,contrib4 ,univ4 ,mi*igan ,mus4 ,paleo41 #af7a73a-bbc1 #af pls41 #ah figs4 ,,hibb>d1 ,c4 ,w41 & ,,wilson1 ,j4 ,a4 #aiej4 ,a new rod5t f subsurface /ratum 9 ,bee ,c\nty1 ,texas4 ,j\r4 ,paleo41 #bd3fba-fbc1 ,septemb]4 ,,hoop]1 ,e4 ,t4 #aidf4 ,two g5]a ( pocket goph]s %\ld be cong5]ic4 ,j\r4 ,mamm41 #bg3cig-cii1 ,novemb]1 #aife4 ,,james1 ,g4 ,t4 #aifc4 ,paleontology & nonm>9e /ratigraphy ( ! ,cuyama ,valley ,badl&s1 ,cali=nia4 ,"p ,i4 ,geology1 faunal int]pretations1 & sy/ematic descriptions ( ,*iropt]a1 ,insectivora1 & ,rod5tia4 ,univ4 ,cali=nia ,publ4 ,geol4 ,sci41 #de3;iv #agj1 #h pls41 #ec figs41 ,june #bf4 ,,johnson1 ,c4 ,s41 & ,,savage1 ,d4 ,e4 #aiee4 ,a survey ( v>i\s ,late ,c5ozoic v]tebrate faunas ( ! ,panh&le ( ,texas1 ,"p ,i4 ,univ4 ,cali=nia ,publ4 ,geol4 ,sci41 #ca3bg-ej4 ,,k5deigh1 ,c4 ,s4 #aifa4 ,animal ,ecology4 ,pr5tice ,hall1 ,inc41 ,englewood ,clifts1 ,new ,j]sey1 pp4 x #dfh4 ,,kurt51 ,b4 #aife4 ,! ,plei/oc5e ,felidae ( ,florida4 ,bull4 ,florida ,/ate ,mus41 #i7f73bae-bgc1 ,june #h4 ,,leidy1 ,j4 #ahfi4 ,! ext9ct mammalian fauna ( ,dakota & ,nebraska--toge!r ) a synopsis ( ! mammalian rema9s ( ,nor? ,am]ica4 ,philadelphia1 #dgb pp41 #cj pls4 ,,macdonald1 ,j4 ,r4 #aifc4 ,! ,mioc5e faunas f ! ,w\nd$ ,knee area ( we/]n ,nor? ,dakota4 ,bull4 ,am]4 ,mus4 ,nat4 ,hi/41 #abe3ada-cbh1 #cj figs41 ,augu/ #bf4 ,,maldonado-,,ko]dell1 ,m4 #aidh4 ,los v]tebrados fosiles del ,cuat]n>io en ,mexico4 ,rev4 ,soc4 ,mex4 ,hi/4 ,nat41 #i3a-ce1 ,june4 ,,m>%1 ,o4 ,c4 #ahga4 ,notice ( "s new fossil mammals & birds f ! ,t]ti>y =mations ( ! we/4 ,am]4 ,j\r4 ,sci4 & ,art1 #c3abj-abg4 ,,mat!w1 ,w4 ,d4 #ahii4 ,a provisional classification ( ! fre%-wat] ,t]ti>y ( ! ,we/4 ,bull4 ,am]4 ,mus4 ,nat4 ,hi/41 #ab3ai-ge1 ,m>* #ca4 #aijb4 ,li/ ( ! ,plei/oc5e fauna f ,hay ,spr+s1 ,nebraska4 ,bull4 ,am]4 ,mus4 ,nat4 ,hi/41 #af3cag-cbb1 ,septemb] #be4 #aiji4 ,faunal li/s ( ! ,t]ti>y mammalia ( ! we/4 ,bull4 ,u4 ,s4 ,geol4 ,surv41 #cfa3ia-ach4 #aiaj4 ,notes on ! o/eology & relation%ips ( ,p>amys1 & ! aff9ities ( ! ,is*yromyidae4 ,bull4 ,am]4 ,mus4 ,nat4 ,hi/41 #bh3 #dc-gb1 #ai figs41 ,m>* #bb4 #aibc;a4 ,fossil bones 9 ! rock4 ,! fossil qu>ry ne> ,agate1 ,si\x ,c\nty1 ,nebraska4 ,nat4 ,hi/41 #bc3ceh-cfi4 #aibc;b4 ,! occurr5ce ( ! ,hesp]opi!cus too?4 ,am]4 ,mus4 ,novit41 #ec3aa-ac1 ,janu>y #f4 #aibd4 ,?ird ,contribution to ! ,snake ,creek ,fauna4 ,bull4 ,am]4 ,mus4 ,nat4 ,hi/41 #ej3ei-baj1 ,july #c4 ,,mat!w1 ,w4 ,d41 & ,,cook1 ,h4 ,j4 #aiji4 ,a ,plioc5e fauna f we/]n ,nebraska4 ,bull4 ,am]4 ,mus4 ,nat4 ,hi/41 #bf3cfa-dad4 ,,may]-,,oakes1 ,w4 ,j4 #aiei4 ,a /ratigraphic excavation at ,el ,risco1 ,mexico4 ,proc4 ,am]4 ,phil4 ,soc41 #ajc3ccb-cgc1 ,june #ae1 #aiei4 ,,mcgrew1 ,p4 ,o4 #aidd4 ,an e>ly ,plei/oc5e 7,blancan7 fauna f ,nebraska4 ,field ,mus4 ,nat4 ,hi/41 ,geol4 ,s]41 #i7b73cc-ff1 ,janu>y #bj4 ,,m]riam1 ,c4 ,h4 #ahie4 ,monographic revision ( ! pocket goph]s1 family ,geomyidae 7exclusive ( ! species ( ,?omomys74 ,n4 ,am]4 ,fauna1 #h3a-beh1 #ai pls41 #d maps1 #ha figs41 ,janu>y #ca4 ,,mill]1 ,g4 ,s41 ,,jr41 & ,,gidley1 ,j4 ,w4 #aiah4 ,synopsis ( ! sup]g5]ic gr\ps ( rod5ts4 ,j\r4 ,wa%+ton ,acad4 ,sci41 #h3dca-ddh1 ,july #ai4 ,,mill]1 ,g4 ,s41 ,,jr41 & ,,kellogg1 ,r4 #aiee4 ,li/ ( ,nor? ,am]ican ,rec5t mammals4 ,bull4 ,u4 ,s4 ,nat4 ,mus41 #bje3xii #ied1 ,m>* #c4 ,,moos]1 ,o4 #aiei4 ,la fauna ,c$azo del ,plei/oc5o en ,aguascali5tes4 ,an4 ,in/4 ,biol4 ,mex41 #bi7a & #b73dji-deb1 #bi figs4 ,,paulson1 ,g4 ,r4 #aifa4 ,! mammals ( ! ,cudahy fauna4 ,pap]s ,mi*igan ,acad4 ,sci41 ,arts1 & ,lett]s1 #df3abg-aec4 ,,pet]s1 ,w4 #ahgd4 ,ub] die ,tas*5mause und e9e neue ,art d]selb51 ,het]omys adsp]sus1 aus ,panama4 ,monatsb]4 ,k4 ,acad4 ,wiss5s*4 ,b]l91 pp4 #ced-cei1 #a pl4 ,,ray1 ,c4 ,e4 #aieh4 ,additions to ! ,plei/oc5e mammalian fauna f ,melb\rne1 ,florida4 ,bull4 ,mus4 ,comp4 ,zool41 #aai3dba-ddi1 #e figs41 ,novemb]4 ,,russell1 ,r4 ,j4 #aifj4 ,plei/oc5e pocket goph]s f ,san ,josecito ,cave1 ,nuevo ,len1 ,mxico4 ,univ4 ,kansas ,publ41 ,mus4 ,nat4 ,hi/41 #i3eci-edh1 ,janu>y #ad4 ,,savage1 ,d4 ,e4 #aiea4 ,late ,c5ozoic v]tebrates ( ! ,san ,francisco ,bay ,region4 ,univ4 ,cali=nia ,publ4 ,geol4 ,sci41 #bh3bae-cad1 ,m>* #bc4 ,,s*ultz1 ,c4 ,b41 & ,,h[>d1 ,e4 ,b4 #aice4 ,! fauna ( ,burnet ,cave1 ,guadalupe ,m\nta9s1 ,new ,mexico4 ,proc4 ,acad4 ,nat4 ,sci4 ,philadelphia1 #hg3bgc-bih1 #cg figs41 #f pls4 ,,s*ultz1 ,c4 ,b41 ,,lu5+ho5]1 ,g4 ,c41 & ,,frank=t]1 ,w4 ,d4 #aiea4 ,a graphic rsum ( ! ,plei/oc5e ( ,nebraska4 ,bull4 ,univ4 ,nebraska ,/ate ,mus41 #c7f73a-da1 ,july4 ,,s*ultz1 ,c4 ,b41 & ,,/\t1 ,t4 ,m4 #aidh4 ,plei/oc5e mammals & t]races 9 ! ,great ,pla9s4 ,bull4 ,geol4 ,soc4 ,am]41 #ei3eec-ehi1 ,june4 ,,s*ultz1 ,c4 ,b41 & ,,tann]1 ,l4 ,g4 #aieg4 ,m$ial ,plei/oc5e fossil v]tebrate localities 9 ,nebraska4 ,univ4 ,nebraska ,/ate ,mus41 #d7d73ei-ha1 ,septemb]4 ,,s*ultz1 ,g4 ,e4 #aife4 ,plei/oc5e v]tebrates f ! ,butl] ,spr+s local fauna1 ,meade ,c\nty1 ,kansas4 ,pap]s ,mi*igan ,acad4 ,sci41 ,arts1 & ,lett]s1 #ej3bce-bfe4 ,,s*ultz1 ,j4 ,r4 #aich4 ,a late ,quat]n>y mammal fauna f ! t> seeps ( ,mc,kittrick1 ,cali=nia4 ,c>negie ,in/4 ,wa%+ton ,publ41 #dhg3aaa-bae1 ,july #f4 ,,%otwell1 ,j4 ,a4 #aief4 ,hemphillian mammalian assemblage f nor!a/]n ,oregon4 ,bull4 ,geol4 ,soc4 ,am]41 #fg3gag-gch1 #g figs41 ,june4 #aifc4 ,! ,juntura ,bas93 /udies 9 e>? hi/ory & paleoecology4 ,mammalian fauna ( ! ,drewsey ,=mation1 ,b>tlett ,m\nta9s1 ,dr9kwat] & ,otis ,bas9 local faunas4 ,trans4 ,am]4 ,phil4 ,soc41 n4s41 #ec7a73a-gg1 ,april4 ,,simpson1 ,g4 ,g4 #aibh4 ,plei/oc5e mammals f a cave 9 ,citrus ,c\nty1 ,florida4 ,am]4 ,mus4 ,novit41 #cbh3a-d1 ,octob] #bf4 #aibi4 ,plei/oc5e ,mammalian fauna ( ! ,sem9ole ,field1 ,p9ellas ,c\nty1 ,florida4 ,bull4 ,am]4 ,mus4 ,nat4 ,hi/41 #ef3efa-eii4 #aide4 ,! pr9ciples ( classification & a classification ( mammals4 ,bull4 ,am]4 ,mus4 ,nat4 ,hi/41 #he3 pp4 xvi #cej1 ,octob] #e4 #aiec4 ,! major features ( evolution4 ,columbia ,univ4 ,press1 ,new ,york1 pp4 xx #dcd1 #eb figs4 ,,s9clair1 ,w4 ,j4 #aije4 ,new ,mammalia f ! ,quat]n>y caves ( ,cali=nia4 ,bull4 ,dept ,geol4 ,univ4 ,cali=nia1 #d3ade-afa1 pls4 #ai & #bc4 ,,sk9n]1 ,m4 ,f4 #aidb4 ,! fauna ( ,papago ,spr+s ,cave1 ,arizona4 ,bull4 ,am]4 ,mus4 ,nat4 ,hi/41 #hj3adc-bbj1 ,novemb] #f4 ,,slaught]1 ,b4 ,h41 & ,,hoov]1 ,b4 ,r4 #aifc4 ,sulphur ,riv] ,=mation & ! ,plei/oc5e mammals ( ! ,b5 ,frankl9 local fauna4 ,j\r4 ,grad4 ,resc4 ,c5t]1 #ca7c73acb-adh1 ,june4 ,,slaught]1 ,b4 ,h41 & ,,rit*ie1 ,f4 #aifc4 ,plei/oc5e mammals ( ! ,cle> ,creek local fauna1 ,d5ton ,c\nty1 ,texas4 ,j\r4 ,grad4 ,resc4 ,c5t]1 #ca7c73aag-aca1 ,june4 ,,/>rett1 ,a4 #aief4 ,plei/oc5e mammals ( ! ,b]5ds fauna ( ,oklahoma4 ,j\r4 ,paleo41 #cj3aahg-aaib4 ,,/eph5s1 ,j4 ,j4 #aifj4 ,/ratigraphy & paleontology ( a late ,plei/oc5e ,bas91 ,h>p] ,co41 ,oklahoma4 ,bull4 ,geol4 ,soc4 ,am]41 #ga3afge-agjb1 ,novemb]4 ,,/ra91 ,w4 ,s4 #aiff4 ,blancan mammalian fauna & ,plei/oc5e =mations1 ,hudspe? ,c\nty1 ,texas4 ,bull ,texas ,memorial ,mus41 #aj3a-ee1 #h figs41 #ac pls41 ,febru>y4 ,,tamsitt1 ,j4 ,r4 #aieg4 ,p]omyscus f ! ,late ,plei/oc5e ( ,texas4 ,! ,texas ,j\r4 ,sci41 #i7c73cee-cfc1 ,septemb]4 ,,wat]h\se1 ,g4 ,r4 #ahci4 ,obs]vations on ! ,rod5tia1 ) a view to po9t out ! gr\ps1 z indicat$ by ! /ructure ( ! crania1 9 ?is ord] ( mammals4 ,mag4 ,nat4 ,hi/41 new s]ies1 #c3ij-if1 #ahd-ahh1 #bgd-bgi1 #eic-fjj1 #a pl4 #ahda4 ,obs]vations on ! ,rod5tia4 ,ann4 ,mag4 ,nat4 ,hi/41 #h3ha-hd1 pl4 #b4 #ahdh4 ,a natural hi/ory ( ! mammalia4 ,vol4 #b1 conta9+ ! ord] ,rod5tia1 or gnaw+ mammalia4 ,hippolyte ,bailli]e1 ,london1 #ejj pp41 #ba pls4 ,,wat]s1 ,j4 ,h4 #aieg4 ,second f9d ( ,?omomys talpoides f late ,plei/oc5e 9 ,kansas4 ,j\r4 ,mamm41 #cg3edj-edb4 ,,:ite1 ,j4 ,a41 & ,,d[ns1 ,t4 #aifa4 ,a new ,geomys f ! ,vallecito ,creek ,plei/oc5e ( ,cali=nia1 ) notes on v>iation 9 ,rec5t & fossil species4 ,contr4 9 ,sci5ce1 ,los ,angeles ,co4 ,mus41 #db3a-cd1 ,june #cj4 ,,wilson1 ,r4 ,w4 #aicc;a4 ,plei/oc5e mammalian fauna f ! ,c>p9t]ia asphalt4 ,c>negie ,in/4 ,wa%+ton ,publ41 #ddj3ei-gf1 ,novemb]4 #aicc;b4 ,a rod5t fauna f ! lat] ,c5ozoic b$s ( s\?we/]n ,idaho4 ,c>negie ,in/4 ,wa%+ton ,publ4 #ddj3aag-ace1 #h figs41 #b pls41 ,decemb]4 #aicf4 ,a ,plioc5e rod5t fauna f ,smi?'s ,valley1 ,nevada4 ,c>negie ,in/4 ,wa%+ton ,publ41 #dgc3ae-cd4 #aicg4 ,plioc5e rod5ts ( we/]n ,nor? ,am]ica4 ,c>negie ,in/4 ,wa%+ton ,publ4 #dhg3ba-gc1 ,july #bc4 #aidj4 ,two new ,eoc5e rod5ts f ,cali=nia4 ,c>negie ,in/4 ,wa%+ton ,publ41 #ead3he-ie1 ,june #bg4 #aidi4 ,e>ly ,t]ti>y rod5ts ( ,nor? ,am]ica4 ,c>negie ,in/4 ,wa%+ton ,publ41 #ehd3fg-afd1 ,june #bb4 ,,w+e1 ,h4 #aibd4 ,patt$yr-,slaegt]4 ,vol4 #b1 ,rod5tia1 ,c>nivora1 ,primates4 ,h4 ,hag]ups ,=lag1 ,cop5hag51 #cba pp4 ,,wood1 ,a4 ,e4 #aice4 ,evolution & relation%ip ( ! het]omyid rod5ts4 ,ann4 ,c>negie ,mus41 #bd3gc-bfb1 ,may #ac4 #aicf4 ,geomyid rod5ts f ! ,middle ,t]ti>y4 ,am]4 ,mus4 ,novit41 #hff3a-ca1 ,july #b4 #aiej4 ,a new geomyid rod5t f ! ,mioc5e ( ,montana4 ,ann4 ,c>negie ,mus41 #ca3cce-cch1 #a fig4 #aiee4 ,a ,revis$ classification ( rod5ts4 ,j\r4 ,mamm41 #cf3afe-ahg1 ,may #bf4 ,,wood1 ,a4 ,e41 & ,,wilson1 ,r4 ,w4 #aicf4 ,a sugge/$ nom5clature = ! cusps ( ! *eek tee? ( rod5ts4 ,j\r4 ,paleo41 #aj3chh-cia1 #b figs41 ,july4 ,transmitt$ ,may #bi1 #aifg4 99 99 99 99 99 ,transcrib]'s note3 ,all obvi\s typographical errors 7 correct$4 ,m9or *anges 7 made to /&>dize ! text to mat* ! mo/ preval5t =m us$4 ,typographical ,corrections ,page ,correction #dgg cumb]l&icus cumb]l&ius #ece brea? bread?