# List of the Cenozoic life of Utah

This list of the Cenozoic life of Utah contains the various prehistoric life-forms whose fossilized remains have been reported from within the US state of Utah and are between 66 million and 10,000 years of age.

## A

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* E
* F
* G
* H
* I
* J
* K
* L
* M
* N
* O
* P
* Q
* R
* S
* T
* U
* V
* W
* X
* Y
* Z
* Abies
* †Achaenodon
** †Achaenodon uintensis – type locality for species
* †Acmeodon
* †Acrocera
** †Acrocera hirsuta – type locality for species
* †Aenocyon
** †Aenocyon dirus – or unidentified comparable form
* †Aepinacodon
* †Aethomylos
** †Aethomylos simplicidens
* †Ageina – or unidentified comparable form
* Life restoration of the Eocene-Oligocene even-toed ungulate Agriochoerus †Agriochoerus
** †Agriochoerus maximus
* Alligator
* †Allognathosuchus – or unidentified comparable form
* †Allophaiomys
** †Allophaiomys pliocaenicus
* Amia
** †Amia uintensis
* Amyda
** †Amyda crassa – type locality for species
** †Amyda gregaria
* †Amynodon
** †Amynodon advenus
** †Amynodon reedi
* †Anaptomorphus
** †Anaptomorphus aemulus
* †Anemorhysis
* †Anisonchus
** †Anisonchus athelas
** †Anisonchus oligistus
** †Anisonchus onostus
** †Anisonchus sectorius
* Fossilized shell of the Eocene-Oligocene turtle Anosteira †Anosteira
** †Anosteira ornata
* Anthonomus
** †Anthonomus soporus
* †Antiacodon
** †Antiacodon pygmaeus
* Antilocapra
** †Antilocapra americana – or unidentified comparable form
* Apalone
* †Apataelurus
** †Apataelurus kayi – type locality for species
* †Apatemys
** †Apatemys bellulus – or unidentified comparable form
** †Apatemys bellus – or unidentified comparable form
** †Apatemys rodens – or unidentified comparable form
** †Apatemys uintensis – type locality for species
* †Aphronorus
** †Aphronorus simpsoni
* Restoration of an Arctodus, or short-faced bear, with a human to scale †Arctodus
** †Arctodus simus
* †Armintodelphys
** †Armintodelphys dawsoni
* †Artemisia
* †Asilopsis – type locality for genus
** †Asilopsis fusculus – type locality for species
* †Asilus
** †Asilus palaeolestes – type locality for species
* †Aulobaris
** †Aulobaris circumscripta
** †Aulobaris comminuta – type locality for species
* †Auxontodon
** †Auxontodon pattersoni

## B

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* †Baena
** †Baena arenosa – type locality for species
** †Baena emiliae
* †Baptemys
* †Basirepomys
** †Basirepomys robertsi – type locality for species
* †Bembidium
** †Bembidium exoletum – type locality for species
* Bison
** †Bison latifrons – tentative report
* †Bittacus
** †Bittacus egestionis – type locality for species
* †Blickomylus
** †Blickomylus moroni – type locality for species
* †Bootherium
** †Bootherium bombifrons
* Fossilized skeleton of the Eocene crocodilian Boverisuchus †Boverisuchus
** †Boverisuchus vorax – type locality for species
* †Brachyhyops
** †Brachyhyops wyomingensis
* Brachylagus
** †Brachylagus idahoensis – or unidentified comparable form
* †Bridgeremys
** †Bridgeremys pusilla – tentative report
* †Bunomeryx
** †Bunomeryx montanus – type locality for species

## C

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* Life restoration of the Pliocene-Holocene camel Camelops †Camelops
** †Camelops hesternus – or unidentified comparable form
* Camponotus
** †Camponotus vetus – type locality for species
* Canis
** †Canis latrans – tentative report
** †Canis lupus
* †Capricamelus
* †Carabites
** †Carabites eocenicus – type locality for species
** †Carabites exanimus – type locality for species
* †Catopsalis
** †Catopsalis fissidens
* †Cedrelospermum
** †Cedrelospermum nervosum
* †Centetodon
** †Centetodon bembicophagus
** †Centetodon pulcher
* Life restoration of the Late Cretaceous-Eocene choristoderan reptile Champsosaurus †Champsosaurus
* Chara
* Cheilosia
** †Cheilosia scudderi
* †Chipetaia
** †Chipetaia lamporea – type locality for species
* †Chisternon
** †Chisternon undatum – type locality for species
* †Chriacus
** †Chriacus baldwini
* †Cicindelopsis – type locality for genus
** †Cicindelopsis eophilus – type locality for species
* †Colodon
* †Compsemys
** †Compsemys victa
* †Conacodon
** †Conacodon kohlbergeri
* †Coniatus
** †Coniatus refractus
* †Conoryctella – type locality for genus
** †Conoryctella dragonensis – type locality for species
** †Conoryctella pattersoni
* †Copemys
** †Copemys mariae – or unidentified related form
* †Coryphodon
** †Coryphodon lobatus
* †Cristadjidaumo – type locality for genus
** †Cristadjidaumo mckennai – type locality for species
* Crocodylus
** Fossilized skull of the Eocene crocodilian Crocodylus acer †Crocodylus acer – type locality for species
** †Crocodylus affinis
* †Crypholestes
* Culex
** †Culex proavitus – type locality for species
* †Cupidinimus
* †Cuterebra
** †Cuterebra ascarides
* †Cyttaromyia – type locality for genus
** †Cyttaromyia fenestrata – type locality for species

## D

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* †Desmatoclaenus
** †Desmatoclaenus hermaeus
* Dicranomyia
** †Dicranomyia primitiva – type locality for species
** †Dicranomyia rostrata – type locality for species
** †Dicranomyia stigmosa – type locality for species
* Mounted fossilized skeleton of the Miocene-Pliocene horse Dinohippus †Dinohippus
* †Diplacodon
** †Diplacodon elatus
** †Diplacodon emarginatus – type locality for species
* †Diplobunops
** †Diplobunops crassus
** †Diplobunops matthewi
* †Diprionomys
** †Diprionomys minimus – or unidentified comparable form
* †Dipsalidictis
** †Dipsalidictis transiens
* †Draconodus
** †Draconodus apertus
* †Dracontolestes
** †Dracontolestes aphantus – type locality for species
* †Duchesnehippus
** †Duchesnehippus intermedius
* †Duchesneodus
** †Duchesneodus uintensis

## E

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* Z
* Fossilized shell of the Eocene turtle Echmatemys †Echmatemys
** †Echmatemys depressa – type locality for species
** †Echmatemys douglassi – type locality for species
** †Echmatemys septaria – type locality for species
** †Echmatemys uintensis
* †Ectoconus
** †Ectoconus ditrigonus
** †Ectoconus symbolus
* †Ellipsodon
** †Ellipsodon grangeri
** †Ellipsodon lemuroides
** †Ellipsodon sternbergi – type locality for species
* †Elliptio
* Life restoration of a pair of the Eocene uintathere mammal Eobasileus. Charles R. Knight (1890s). †Eobasileus
** †Eobasileus cornutus
* †Eobracon – type locality for genus
** †Eobracon cladurus – type locality for species
* †Eocaenonemonyx
** †Eocaenonemonyx kuscheli – type locality for species
* †Eoconodon
* †Eodiploglossus
** †Eodiploglossus borealis
* †Eoformica
** †Eoformica pinguis – type locality for species
* †Eomoropus
** †Eomoropus amarorum – type locality for species
** †Eomoropus anarsius
* †Eonessa – type locality for genus
** †Eonessa anaticula – type locality for species
* †Epicaerus
** †Epicaerus effossus
** †Epicaerus eradicatus
** †Epicaerus evigoratus
** †Epicaerus exanimis
** †Epicaerus subterraneus
** †Epicaerus terrosus
* †Epihippus
** †Epihippus gracilis
* †Epiphanis
** †Epiphanis deletus – type locality for species
* †Epitriplopus
** †Epitriplopus uintensis
* Equus
** †Equus conversidens – tentative report
* Erethizon
** †Erethizon dorsatum – tentative report
* †Eucastor
** †Eucastor tortus – or unidentified comparable form
* Fossil of the Eocene bee Euglossopteryx †Euglossopteryx – type locality for genus
** †Euglossopteryx biesmeijeri – type locality for species
* Eutamias
** †Eutamias minimus

## G

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* M
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* †Glyptosaurus
** †Glyptosaurus sylvestris
* †Gnoriste
** †Gnoriste dentoni – type locality for species
* †Goniacodon
** †Goniacodon hiawathae
* †Griphomys

## H

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* †Hadrianus
** †Hadrianus corsoni
** †Hadrianus utahensis – type locality for species
* †Haplaletes
** †Haplaletes andakupensis
* †Haploconus
** †Haploconus angustus
** †Haploconus elachistus
* †Haplolambda – or unidentified comparable form
** †Haplolambda simpsoni – type locality for species
* Fossilized skull of the mesonychian mammal Harpagolestes †Harpagolestes
** †Harpagolestes brevipes – type locality for species
** †Harpagolestes leotensis – type locality for species
** †Harpagolestes uintensis
* †Helaletes
** †Helaletes nanus
* †Helodermoides – tentative report
* †Heptacodon
* †Herpetotherium
** †Herpetotherium innominatum
* †Hesperolagomys
** †Hesperolagomys galbreathi
* †Hessolestes
** †Hessolestes ultimus – type locality for species
* †Heteraletes
** †Heteraletes leotanus
* †Hoplochelys
* Life restoration of the Eocene-Miocene creodont mammal Hyaenodon †Hyaenodon
** †Hyaenodon vetus – or unidentified comparable form
* Hydrobia – or unidentified comparable form
* †Hylobius
** †Hylobius deleticius – type locality for species
* †Hylomeryx
** †Hylomeryx annectens
** †Hylomeryx quadricuspis – type locality for species
* †Hyopsodus
** †Hyopsodus minusculus
** †Hyopsodus paulus
** †Hyopsodus uintensis – type locality for species
* †Hypohippus
* †Hypolagus
** †Hypolagus vetus
* †Hyrachyus
** †Hyrachyus eximius
** †Hyrachyus modestus
* †Hyracodon
** †Hyracodon medius
* †Hyracotherium
** †Hyracotherium vasacciense

## I

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* †Isectolophus – type locality for genus
** †Isectolophus annectens – type locality for species

## J

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* †Janimus
** †Janimus rhinophilus – type locality for species

## K

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* †Kimbetohia
** †Kimbetohia campi

## L

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* Laccophilus
* †Lambdotherium
* †Lasioptera
** †Lasioptera recessa – type locality for species
* †Leistotrophus
** †Leistotrophus patriarchicus – type locality for species
* Lemmiscus
** †Lemmiscus curtatus
* Lepisosteus
** †Lepisosteus simplex
* Life restoration of the Eocene-Oligocene even-toed ungulate Leptomeryx †Leptomeryx
* †Leptoreodon
** †Leptoreodon marshi
* †Leptotragulus
** †Leptotragulus clarki
** †Leptotragulus medius – type locality for species
** †Leptotragulus proavus
* Lepus
** †Lepus townsendii – or unidentified comparable form
* †Limalophus
** †Limalophus compositus
** †Limalophus receptus – type locality for species
* Top view of a fossilized skull of the Eocene creodont mammal Limnocyon †Limnocyon
** †Limnocyon potens
** †Limnocyon verus – or unidentified comparable form
* †Liodontia
* †Lioplacoides – or unidentified comparable form
* †Litaletes
** †Litaletes gazini
* †Lithadothrips – type locality for genus
** †Lithadothrips vetusta – type locality for species
* †Loxolophus
** †Loxolophus pentacus
** †Loxolophus spiekeri
* A living Lynx Lynx
** †Lynx canadensis – or unidentified comparable form

## M

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* †Macrotarsius
** †Macrotarsius jepseni – type locality for species
* †Mammut
** †Mammut americanum
* †Mammuthus
** †Mammuthus columbi
** Life restorations of a Mammut americanum, or American mastodon (right), and a Mammuthus primigenius, or wooly mammoth (left) †Mammuthus primigenius
* Marsilea
** †Marsilea sprungerorum
* †Megalamynodon
** †Megalamynodon regalis – type locality for species
* †Megalonyx
** †Megalonyx jeffersonii
* †Menops
** †Menops marshi
* †Merriamoceros
* †Mesomeryx – type locality for genus
** †Mesomeryx grangeri – type locality for species
* Life restoration of the Eocene mammal Mesonyx †Mesonyx
** †Mesonyx obtusidens
* †Metaliomys – type locality for genus
** †Metaliomys sevierensis – type locality for species
* †Metanoiamys
** †Metanoiamys lacus
* †Metarhinus
** †Metarhinus diploconus
** †Metarhinus fluviatilis – type locality for species
** †Metarhinus parvus
* †Metatelmatherium
** †Metatelmatherium ultimum – type locality for species
* Life restoration of the Paleocene-Eocene mammal Miacis †Miacis
** †Miacis parvivorus – or unidentified comparable form
* †Microparamys
** †Microparamys dubius
** †Microparamys minutus
* †Micropternodus
* †Microsyops
* Microtus
** †Microtus montanus
** †Microtus paroperarius
* Mictomys
** †Mictomys borealis
* †Mimomys
** †Mimomys dakotaensis – or unidentified comparable form
* †Mimotricentes
* †Miocyon
** †Miocyon major – or unidentified comparable form
** †Miocyon scotti – type locality for species
** †Miocyon vallisrubrae – type locality for species
* Mustela
** †Mustela richardsonii – tentative report
* †Myrmecoboides
* †Mytonolagus
** †Mytonolagus petersoni – type locality for species
* †Mytonomeryx
** †Mytonomeryx scotti – type locality for species
* †Mytonomys
** †Mytonomys mytonensis
** †Mytonomys robustus – type locality for species

## N

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* †Nemotelus
** †Nemotelus eocenicus – type locality for species
* Neogale
** †Neogale vison
* †Neoplagiaulax
** †Neoplagiaulax macintyrei
* Neoptochus – tentative report
* Neotamias
* Neotoma
* †Notharctus
** Mounted fossilized skeleton of the Eocene primate Notharctus tenebrosus †Notharctus tenebrosus – or unidentified comparable form
* †Nyctitherium
** †Nyctitherium serotinum

## O

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* A living Odocoileus deer Odocoileus
* †Oliveremys
** †Oliveremys uintaensis
* †Omomys
** †Omomys carteri
** †Omomys lloydi – type locality for species
* Ondatra
* †Onychodectes
** †Onychodectes tisonensis – or unidentified comparable form
* †Oodectes – tentative report
* Ophryastes
** †Ophryastes petrarum
* †Ophryastites
** †Ophryastites digressus – type locality for species
* †Orelladjidaumo – or unidentified comparable form
* †Oromeryx
** †Oromeryx plicatus – type locality for species
* †Ourayia
** †Ourayia hopsoni
** †Ourayia uintensis – type locality for species
* †Oxyacodon
** †Oxyacodon apiculatus
** †Oxyacodon ferronensis – type locality for species
** †Oxyacodon marshater – type locality for species
* †Oxyaenodon
** †Oxyaenodon dysodus
* †Oxyclaenus
** †Oxyclaenus pugnax
* †Oxygonus
** †Oxygonus mortuus – type locality for species
* †Oxytomodon
** †Oxytomodon perissum

## P

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* †Pachymerus
** †Pachymerus petrensis – type locality for species
* †Paenemarmota
** †Paenemarmota sawrockensis
* †Palaeictops
** †Palaeictops bridgeri
* †Palaeoeristalis – type locality for genus
** †Palaeoeristalis tesselatus – type locality for species
* †Palaeothrips – type locality for genus
** †Palaeothrips fossilis – type locality for species
* †Palaeoxantusia
* †Pantolestes
** †Pantolestes longieundus – or unidentified comparable form
* †Paradjidaumo
** †Paradjidaumo alberti – or unidentified comparable form
** †Paradjidaumo trilophus
* Fossilized skeleton of the Pliocene-Pleistocene ground sloth Paramylodon †Paramylodon
** †Paramylodon harlani – or unidentified comparable form
* †Paramys
** †Paramys compressidens – type locality for species
** †Paramys delicatus
** †Paramys leptodus
* †Parasauromalus
** †Parasauromalus olseni
* †Parectypodus
* †Pareumys
** †Pareumys grangeri
** †Pareumys guensburgi – type locality for species
** †Pareumys milleri – type locality for species
** †Pareumys troxelli
* †Paromomys
** †Paromomys depressidens
* †Paronychomys
** †Paronychomys lemredfieldi
* †Paropsocus – type locality for genus
** †Paropsocus disjunctus – type locality for species
* †Passaliscomys – type locality for genus
** †Passaliscomys priscus – type locality for species
* †Pauromys
* †Penetrigonias
** †Penetrigonias dakotensis
* †Pentacemylus
** †Pentacemylus leotensis
** †Pentacemylus progressus – type locality for species
* †Peradectes
** †Peradectes chesteri
* Fossilized mandible of the Eocene-Miocene mammal Peratherium †Peratherium
** †Peratherium marsupium
* †Periptychus
** †Periptychus carinidens
** †Periptychus coarctatus
* Peromyscus
** †Peromyscus maniculatus
* Phenacomys
** †Phenacomys gryci – or unidentified comparable form
** †Phenacomys intermedius
* †Phygadeuon
** †Phygadeuon petrifactellus – type locality for species
* Phyllobius
** †Phyllobius avus
** †Phyllobius carcerarius
* †Phyllophaga
** †Phyllophaga avus – type locality for species
* Physa
* Picea
* A living Pinus, or pine tree Pinus
* †Plastomenoides
** †Plastomenoides lamberti
* †Plastomenus
* Plecia
** †Plecia woodruffi – type locality for species
* †Plesiolestes
** †Plesiolestes nacimienti
* †Poabromylus
** †Poabromylus kayi – type locality for species
* †Poebrodon
** †Poebrodon kayi – type locality for species
* †Polemonium – or unidentified comparable form
* †Presbyorniformipes
** †Presbyorniformipes feduccii – type locality for species
* Life restoration of the Paleocene-Eocene waterfowl Presbyornis †Presbyornis – type locality for genus
** †Presbyornis pervetus – type locality for species
** †Presbyornis recurvirostrus – type locality for species
* †Procaimanoidea – type locality for genus
** †Procaimanoidea kayi
** †Procaimanoidea utahensis – type locality for species
* †Procas
** †Procas vinculatus
* †Procynodictis
** †Procynodictis vulpiceps
* †Prodaphaenus
** †Prodaphaenus uintensis – type locality for species
* †Promioclaenus
* †Pronophlebia – type locality for genus
** †Pronophlebia rediviva – type locality for species
* †Propalaeosinopa – tentative report
* †Protadjidaumo
** †Protadjidaumo typus – type locality for species
* †Protictis
** †Protictis haydenianus
* Restorative models in multiple views of the Eocene brontothere Protitanotherium (figure 3) †Protitanotherium
* †Protochriacus
** †Protochriacus simplex
* †Protoptychus
** †Protoptychus hatcheri
* †Protoreodon
** †Protoreodon minor – type locality for species
** †Protoreodon parvus
** †Protoreodon petersoni – type locality for species
** †Protoreodon pumilus – type locality for species
* †Protoselene
** †Protoselene griphus
* Illustration of a fossilized skull of the Eocene camel Protylopus †Protylopus
** †Protylopus annectens – type locality for species
** †Protylopus petersoni
* Fossilized skeleton of the Eocene creodont mammal Proviverra †Proviverra
** †Proviverra longipes
* †Proviverroides
** †Proviverroides piercei – or unidentified comparable form
* †Proxestops – or unidentified comparable form
** †Proxestops silberlingii
* †Pseudodiplacodon
* †Pseudosalix – type locality for genus
** †Pseudosalix handleyi – type locality for species
* †Pseudotomus
** †Pseudotomus eugenei – type locality for species
** †Pseudotomus petersoni – type locality for species
* Illustration of a fossilized skull of the Paleocene multituberculate mammal Ptilodus †Ptilodus
** †Ptilodus mediaevus
** †Ptilodus tsosiensis – or unidentified comparable form

## R

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* †Reithroparamys
** †Reithroparamys sciuroides – type locality for species
* A living Rhinoclemmys, or Neotropical wood turtle Rhinoclemmys – report made of unidentified related form or using admittedly obsolete nomenclature

## S

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* Fossilized skeleton of the Eocene monitor lizard Saniwa †Saniwa
** †Saniwa ensidens
* †Sargus
** †Sargus vetus – type locality for species
* †Scenopagus
** †Scenopagus edenensis
** †Scenopagus priscus
* †Sciuravus
** †Sciuravus altidens – type locality for species
** †Sciuravus eucristadens
** †Sciuravus popi – type locality for species
* †Simidectes – type locality for genus
** †Simidectes magnus – type locality for species
** †Simidectes medius – type locality for species
* †Simimeryx
** †Simimeryx minutus
* †Simimys – or unidentified comparable form
* †Sinopa
** †Sinopa agilis
** †Sinopa major
** †Sinopa rapax
* †Smilodectes
** †Smilodectes gracilis
* Life restoration of the Pleistocene-Holocene saber-tooth cat Smilodon †Smilodon
** †Smilodon fatalis – or unidentified comparable form
* Sorex
** †Sorex palustris
* Spermophilus
** †Spermophilus armatus – or unidentified comparable form
* †Sphenocoelus
** †Sphenocoelus hyognathus
* †Sthenodectes
** †Sthenodectes incisivum – type locality for species
* †Stygimys
** †Stygimys kuszmauli
* †Stylemys
** †Stylemys uintensis – type locality for species
* Life restoration of the Eocene taeniodont mammal Stylinodon mirus †Stylinodon
** †Stylinodon mirus
* †Syntomostylus
** †Syntomostylus rudis

## T

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* Restoration of the Paleocene multituberculate mammal Taeniolabis †Taeniolabis
** †Taeniolabis taoensis
* †Talpavus
** †Talpavus duplus – type locality for species
** †Talpavus nitidus
* †Tapocyon
** †Tapocyon robustus
* Taxidea
** †Taxidea taxus
* †Thisbemys
** †Thisbemys medius
** †Thisbemys uintensis – type locality for species
* Thomomys
** †Thomomys talpoides
* †Tilgidopsis – type locality for genus
** †Tilgidopsis haesitans – type locality for species
* Tinosaurus
** †Tinosaurus stenodon
* †Tricentes
** †Tricentes subtrigonus – type locality for species
* †Triplopus
** †Triplopus implicatus
** †Triplopus obliquidens
** †Triplopus rhinocerinus – type locality for species
* †Trogosus
* †Tylocephalonyx

## U

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* †Uintaceras
** †Uintaceras radinskyi – type locality for species
* †Uintacyon
** †Uintacyon acutus – type locality for species
* †Uintanius
** †Uintanius ameghini
* †Uintasorex
** †Uintasorex parvulus – or unidentified comparable form
* Life restoration of the Eocene mammal Uintatherium †Uintatherium
* †Utahia
** †Utahia kayi – type locality for species

## V

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* †Valenia
** †Valenia wilsoni
* †Viverravus
** †Viverravus gracilis
** †Viverravus minutus
** †Viverravus sicarius
* Viviparus
* Vulpes
** A living Vulpes vulpes, or red fox †Vulpes vulpes

## X

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* †Xestops
** †Xestops vagans
* †Xylotosyrphus – type locality for genus
** †Xylotosyrphus pulchrafenestra – type locality for species

## Z

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* A living Zapus jumping mouse Zapus
* †Zionodon – type locality for genus
** †Zionodon satanus – type locality for species
** †Zionodon walshi – type locality for species