List of the Cenozoic life of South Dakota

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

A

 * †Adeloblarina
 * †Adeloblarina berklandi – or unidentified comparable form
 * †Adjidaumo
 * †Adjidaumo lophatus
 * †Adjidaumo minutus
 * †Aelurodon
 * †Aelurodon ferox
 * †Aelurodon taxoides
 * †Aepinacodon
 * †Aepinacodon deflectus – type locality for species
 * Aepycamelus Alticamelus hharder.jpg †[[Aepycamelus]]
 * †Agnotocastor
 * †Agnotocastor coloradensis
 * †Agnotocastor praetereadens – type locality for species
 * †Agriochoerus
 * †Agriochoerus antiquus
 * †Agriochoerus gaudryi – type locality for species
 * †Alilepus – tentative report
 * †Alismaphyllites
 * †Alismaphyllites grandifolius
 * †Allantodiopsis
 * †Allantodiopsis erosa
 * Alligator
 * Alligator prenasalis.JPG †[[Alligator prenasalis]] – type locality for species
 * †Allomys
 * †Allomys harkseni
 * †Allomys storeri – type locality for species
 * †Allophaiomys
 * †Allophaiomys pliocaenicus
 * †Alwoodia
 * †Ambystoma
 * †Ambystoma minshalli
 * †Ambystoma tigrinum
 * Amebelodon fricki.jpg †[[Amebelodon]]
 * †Ameiseophis
 * †Ameiseophis robinsoni
 * †Ampelopsis
 * †Ampelopsis acerifolia
 * †Amphechinus
 * †Amphechinus horncloudi
 * †Amphicaenopus
 * †Amphicaenopus platycephalus – type locality for species
 * †Amynodontopsis
 * †Amynodontopsis bodei
 * †Anchitherium
 * †Anchitherium clarencei
 * †Ansomys
 * †Ansomys cyanotephrus – type locality for species
 * Antilocapra
 * †Antilocapra americana
 * Apalone
 * †Apalone leucopotamica
 * †Aphelops
 * †Aphelops megalodus
 * †Apternodus
 * †Apternodus mediaevus
 * †Archaeocyon
 * †Archaeocyon leptodus
 * †Archaeocyon pavidus
 * †Archaeohippus
 * †Archaeohippus blackbergi – or unidentified comparable form
 * †Archaeolagus
 * †Archaeolagus macrocephalus – type locality for species
 * †Archaeolagus primigenius – type locality for species
 * Archaeotherium.jpg †[[Archaeotherium]]
 * †Archaeotherium lemleyi – type locality for species
 * †Archaeotherium marshi – type locality for species
 * †Archaeotherium mortoni
 * †Archaeotherium trippensis – type locality for species
 * †Arctodus
 * †Arctodus simus
 * †Arctonasua
 * †Arretotherium
 * †Arretotherium fricki
 * †Arretotherium leptodus – type locality for species
 * Azolla
 * †Azolla schopfi – type locality for species

B

 * Barbourofelis fricki.JPG †[[Barbourofelis]]
 * †Barbourofelis whitfordi
 * †Barbouromeryx
 * †Barbouromeryx trigonocorneus
 * †Bathornis
 * †Bathornis celeripes
 * †Bathornis veredus
 * Bison
 * †Bison latifrons
 * Blarina
 * †Blarina carolinensis – or unidentified comparable form
 * †Boochoerus
 * †Boochoerus angustus – type locality for species
 * †Bothriodon
 * †Bothriodon americanus – type locality for species
 * †Bothriodon rostratus
 * †Brachyerix
 * †Brachyerix incertis – or unidentified comparable form
 * †Brachygaulus – or unidentified comparable form
 * †Brachypsalis
 * †Brachypsalis modicus
 * Brachyrhynchocyon cropped.png †[[Brachyrhynchocyon]]
 * †Brachyrhynchocyon dodgei
 * †Brontops
 * †Brontops bicornutus
 * †Brontops brachycephalus
 * †Brontops dispar
 * †Brontops robustus – type locality for species
 * †Brontops tyleri – type locality for species
 * Bufo
 * †Bufo pliocompactilis
 * †Bufo woodhousei
 * Buteo
 * †Buteo grangeri – type locality for species

C

 * †Calamagras
 * †Calamagras angulatus
 * †Calamagras weigeli
 * †Calippus
 * †Calippus martini
 * †Calippus placidus
 * Camelus hesternus Sergiodlarosa.jpg †[[Camelops]]
 * Canis
 * †Canis dirus – or unidentified comparable form
 * †Canis latrans
 * †Canis lupus
 * †Capacikala
 * †Capacikala parvus
 * †Capatanka
 * †Capatanka gaulodon
 * †Capatanka minor
 * †Carpocyon
 * †Carpocyon robustus
 * Castor
 * †Castor canadensis – or unidentified comparable form
 * †Castor peninsulatus
 * †Catostomus
 * Celtis
 * †Centetodon
 * †Centetodon magnus
 * †Centetodon marginalis
 * †Centetodon wolffi
 * Cercidiphyllum
 * †Cercidiphyllum arcticum
 * Charina bottae.jpg [[Charina]]
 * †Charina prebottae
 * Chrysemys
 * †Chrysemys antiqua
 * †Clinopternodus
 * †Clinopternodus gracilis
 * Cnemidophorus
 * †Colodon
 * †Colodon cingulatus
 * †Colodon occidentalis
 * †Copemys
 * †Copemys longidens
 * †Coprophis – type locality for genus
 * †Coprophis dakotaensis – type locality for species
 * †Cormocyon
 * †Cormocyon haydeni – type locality for species
 * †Cormohipparion
 * †Cormohipparion fricki
 * †Cormohipparion quinni
 * †Cosoryx
 * †Cosoryx furcatus
 * Cranioceras unicornis life restoration.jpg Cranioceras, a relative of modern deer, with anachronistic human to scale]] †Cranioceras
 * †Cranioceras unicornis
 * Crotalus
 * †Crucimys
 * †Crucimys milleri
 * †Cupidinimus
 * †Cupidinimus smaragdinus – type locality for species
 * †Cymaprimadon
 * †Cymaprimadon kenni – type locality for species
 * †Cynarctoides
 * †Cynarctoides acridens
 * †Cynarctoides lemur
 * †Cynarctoides roii
 * †Cynarctus
 * †Cynarctus crucidens
 * †Cynodesmus
 * †Cynodesmus thooides
 * Cynomys

D

 * †Dakotallomys
 * †Dakotallomys lillegraveni
 * †Dakotallomys pelycomyoides
 * †Dakotaophis – type locality for genus
 * †Dakotaophis greeni – type locality for species
 * Daphoenus vetus restoration.jpg †[[Daphoenus]]
 * †Daphoenus hartshornianus
 * †Daphoenus vetus
 * †Dendrochen – type locality for genus
 * †Dendrochen robusta – type locality for species
 * †Desmathyus
 * †Desmathyus pinensis
 * †Desmatippus
 * †Desmatippus texanus
 * †Desmatochoerus
 * †Desmatochoerus megalodon
 * †Desmocyon
 * †Desmocyon thomsoni
 * †Diceratherium
 * †Diceratherium annectens
 * †Diceratherium armatum – type locality for species
 * †Diceratherium radtkei
 * †Diceratherium tridactylum – type locality for species
 * †Dikkomys
 * †Dikkomys matthewi
 * †Dinictis
 * †Dinictis felina
 * †Dinohyus
 * †Dipoides
 * †Disallomys
 * †Disallomys robustus
 * †Domnina
 * †Domnina dakotensis – type locality for species
 * †Domnina gradata
 * †Domnina greeni – type locality for species
 * †Domninoides
 * †Domninoides riparensis – type locality for species
 * †Douglassciurus
 * †Douglassciurus bjorki – type locality for species
 * †Downsimus
 * †Downsimus chadwicki – type locality for species
 * †Duchesnehippus
 * †Duchesnehippus intermedius
 * Duchesneodus-skull.png †[[Duchesneodus]]
 * †Duchesneodus uintensis

E

 * †Ectopocynus
 * †Ectopocynus antiquus
 * †Ekgmowechashala
 * †Ekgmowechashala philotau – type locality for species
 * Elaphe
 * †Elaphe nebraskensis
 * †Elaphe vulpina
 * †Elomeryx
 * †Elomeryx armatus – type locality for species
 * †Elomeryx garbanii – type locality for species
 * †Enhydrocyon
 * †Enhydrocyon crassidens – type locality for species
 * †Enhydrocyon pahinsintewakpa
 * Knight entelodont.jpg †[[Entelodon]]
 * †Entelodon coarctatus – or unidentified comparable form
 * †Entoptychus
 * †Entoptychus leptophrys
 * †Eopelobates
 * †Eopelobates grandis – type locality for species
 * †Epeiromys
 * †Epicyon
 * †Epicyon saevus
 * Equus
 * †Equus francisci
 * †Equus giganteus – or unidentified comparable form
 * †Etheostoma
 * Eubelodon cropped.jpg †[[Eubelodon]]
 * †Eubelodon morrilli
 * †Eucastor
 * †Eucastor tortus
 * †Eucommia
 * †Eucommia serrata
 * Eumeces
 * †Eumeces septentrionalis
 * †Eumys
 * †Eumys brachyodus
 * †Eumys elegans
 * †Eusmilus
 * †Eusmilus sicarius
 * †Eutypomys
 * †Eutypomys montanensis – or unidentified comparable form
 * †Eutypomys thomsoni – type locality for species
 * †Eutypomys wilsoni – or unidentified comparable form

F

 * Sycomoros old.jpg [[Ficus]]
 * †Ficus artocarpoides
 * †Ficus subtruncata
 * †Florentiamys
 * †Florentiamys agnewi – type locality for species
 * †Florentiamys tiptoni
 * †Fossorcastor
 * †Fossorcastor brachyceps

G

 * †Galbreathia
 * †Galbreathia novellus
 * Geomys
 * †Geringia
 * †Geringia gloveri
 * †Geringia mcgregori
 * †Gigantocamelus
 * †Gigantocamelus spatulus
 * Glyptostrobus
 * †Glyptostrobus nordenskioldi
 * Gomphotherium productum.jpg †[[Gomphotherium]]
 * †Gomphotherium obscurum
 * †Grangerimus
 * †Grangerimus dakotensis
 * Graptemys
 * †Gregorymys
 * †Gregorymys curtus – type locality for species
 * †Gregorymys formosus – type locality for species
 * †Gripholagomys – type locality for genus
 * †Gripholagomys lavocati – type locality for species
 * †Guildayomys
 * †Guildayomys hibbardi – or unidentified comparable form

H

 * †Haplomys
 * †Haplomys galbreathi – type locality for species
 * †Heliscomys
 * †Heliscomys senex
 * †Hemiauchenia
 * †Hemicyon
 * †Hemicyon barbouri
 * †Heptacodon
 * †Heptacodon curtus – type locality for species
 * †Heptacodon gibbiceps – type locality for species
 * †Heptacodon occidentale
 * †Herpetotherium
 * †Herpetotherium fugax
 * †Herpetotherium youngi
 * Cynodictis.jpg †[[Hesperocyon]]
 * †Hesperocyon gregarius
 * †Hesperolagomys – tentative report
 * †Hesperopetes
 * †Hesperopetes blacki – type locality for species
 * †Hesperopetes jamesi – type locality for species
 * †Hesperotestudo
 * †Hesperotestudo niobrarensis
 * Heterodon
 * †Heteromeryx
 * †Heteromeryx dispar – type locality for species
 * †Hibbarderix
 * †Hibbarderix obfuscatus
 * †Hibbardomys
 * †Hibbardomys marthae – or unidentified comparable form
 * †Hibbardomys zakrzewskii
 * Hipparion3.jpg †[[Hipparion]]
 * †Hipparion tehonense
 * †Hippotherium
 * †Hippotherium dolichops – type locality for species
 * †Hitonkala
 * †Hitonkala andersontau – type locality for species
 * †Homotherium – or unidentified comparable form
 * †Hoplophoneus
 * †Hoplophoneus cerebralis
 * †Hoplophoneus mentalis
 * †Hoplophoneus occidentalis
 * †Hoplophoneus primaevus
 * Hyaenodon NT small.jpg †[[Hyaenodon]]
 * †Hyaenodon brevirostrus – type locality for species
 * †Hyaenodon crucians
 * †Hyaenodon horridus
 * †Hyaenodon montanus – or unidentified comparable form
 * †Hyaenodon mustelinus – type locality for species
 * Hyla
 * †Hypertragulus
 * †Hypertragulus calcaratus
 * †Hypertragulus dakotensis – type locality for species
 * †Hypisodus
 * †Hypisodus minimus
 * Hypohippus.jpg †[[Hypohippus]]
 * †Hypolagus
 * †Hypolagus fontinalis – type locality for species
 * †Hypolagus vetus – or unidentified comparable form
 * †Hyporhina – type locality for genus
 * †Hyporhina antiqua – type locality for species
 * †Hyracodon
 * †Hyracodon leidyanus – type locality for species
 * †Hyracodon nebraskensis
 * †Hyracodon priscidens – or unidentified comparable form

I

 * Ictalurus
 * †Ischyrocyon
 * †Ischyrocyon gidleyi
 * Ischyromys.jpg †[[Ischyromys]]
 * †Ischyromys typus

J

 * †Javazapus
 * †Javazapus weeksi

K

 * †Kirkomys
 * †Kirkomys martintau
 * †Kirkomys nebraskensis

L

 * †Lambdoceras
 * †Lambdoceras hessei – type locality for species
 * Lampropeltis
 * †Lampropeltis similis
 * †Leidymys
 * †Leidymys blacki
 * †Leidymys juxtaparvulus
 * Lepisosteus
 * Lepomis
 * †Leptarctus
 * †Leptarctus primus – type locality for species
 * Leptauchenia by Apokryltaros cropped.png †[[Leptauchenia]]
 * †Leptauchenia decora – type locality for species
 * †Leptauchenia major – type locality for species
 * †Leptictis
 * †Leptictis dakotensis
 * †Leptictis haydeni
 * †Leptochoerus
 * †Leptochoerus elegans
 * †Leptochoerus supremus – type locality for species
 * †Leptocyon
 * †Leptocyon delicatus – type locality for species
 * †Leptocyon douglassi
 * †Leptocyon gregorii
 * †Leptocyon matthewi
 * †Leptocyon vafer – or unidentified comparable form
 * †Leptocyon vulpinus
 * Leptomeryx BW.jpg †[[Leptomeryx]]
 * †Leptomeryx evansi
 * †Leptoromys
 * †Leptoromys wilsoni – type locality for species
 * Lepus
 * †Lepus americanus – or unidentified comparable form
 * †Lepus ennisianus – or unidentified comparable form
 * †Lignimus
 * †Lignimus austridakotensis – type locality for species
 * †Limnoecus
 * †Limnoecus compressus – or unidentified comparable form
 * †Limnoecus niobrarensis
 * †Longirostromeryx
 * †Longirostromeryx wellsi – type locality for species

M

 * †Macrogenis
 * †Macrogenis crassigenis
 * †Macrognathomys
 * †Macrognathomys gemmacolis – type locality for species
 * †Macrorhineura – type locality for genus
 * †Macrorhineura skinneri – type locality for species
 * †Mammacyon
 * †Mammacyon obtusidens – type locality for species
 * †Mammuthus
 * Columbian mammoth cropped.png †[[Mammuthus columbi]]
 * †Mammuthus primigenius
 * †Manitsha – type locality for genus
 * †Manitsha tanka – type locality for species
 * Martes
 * †Martes campestris
 * †Megacerops
 * †Megacerops coloradensis
 * †Megacerops curtus
 * †Megachoerus – tentative report
 * †Megachoerus latidens – type locality for species
 * †Megalagus
 * †Megalagus primitivus – or unidentified comparable form
 * †Megalagus turgidus
 * †Megaleptictis
 * †Megaleptictis altidens
 * †Megalictis
 * †Megalictis ferox – type locality for species
 * †Megalonyx
 * †Megalonyx leptostomus
 * †Megalonyx wheatleyi
 * †Megapaloelodus – type locality for genus
 * †Megapaloelodus connectens – type locality for species
 * †Megasminthus
 * †Megasminthus gladiofex – type locality for species
 * †Megasminthus tiheni
 * †Megoreodon
 * †Megoreodon grandis
 * †Meniscomys
 * †Meniscomys hippodus
 * Menoceras NT small.jpg †[[Menoceras]]
 * †Menoceras barbouri
 * †Menops
 * †Menops marshi
 * †Menops serotinus
 * †Menops walcotti
 * †Merychippus
 * †Merychippus insignis
 * †Merychyus
 * †Merychyus arenarum
 * †Merychyus minimus
 * †Merychyus novomexicanus
 * Merycochoerus proprius.jpg †[[Merycochoerus]]
 * †Merycochoerus chelydra
 * †Merycochoerus matthewi – type locality for species
 * †Merycodus
 * †Merycodus major – or unidentified comparable form
 * †Merycodus necatus
 * †Merycoides
 * †Merycoides longiceps
 * †Merycoides pariogonus – or unidentified comparable form
 * †Merycoidodon
 * †Merycoidodon bullatus – type locality for species
 * †Merycoidodon culbertsoni – type locality for species
 * †Merycoidodon major
 * Mesocyon.jpeg †[[Mesocyon]]
 * †Mesocyon temnodon
 * †Mesohippus
 * †Mesohippus bairdi
 * †Mesohippus exoletus
 * †Mesoreodon
 * †Mesoreodon chelonyx
 * †Mesoreodon minor
 * †Mesoscalops
 * Knight Metamynodon.jpg †[[Metamynodon]]
 * †Metamynodon chadronensis – type locality for species
 * †Metamynodon planifrons
 * †Michenia
 * †Michenia exilis
 * Microtus
 * †Microtus meadensis
 * †Microtus paroperarius
 * Mictomys
 * †Mictomys kansasensis
 * †Mimomys
 * †Mimomys dakotaensis
 * †Miniochoerus
 * †Miniochoerus affinis
 * †Miniochoerus forsythae
 * †Miniochoerus gracilis
 * †Miniochoerus starkensis – type locality for species
 * †Mioheteromys
 * †Mioheteromys arcarius
 * Miohippus cropped.jpg †[[Miohippus]]
 * †Miohippus annectens – type locality for species
 * †Miohippus equiceps
 * †Miohippus equinanus
 * †Miohippus gemmarosae – or unidentified comparable form
 * †Miohippus gidleyi – type locality for species
 * †Miohippus grandis
 * †Miohippus intermedius – type locality for species
 * †Miohippus obliquidens – type locality for species
 * †Mionictis
 * †Mionictis pristinus
 * †Miortyx – type locality for genus
 * †Miortyx teres – type locality for species
 * †Miospermophilus – or unidentified comparable form
 * †Monosaulax
 * †Monosaulax curtus – or unidentified comparable form
 * †Moropus
 * Mustela
 * †Mustelavus
 * †Mustelavus priscus – type locality for species
 * †Mylagaulus
 * †Mylagaulus sesquipedalis – or unidentified comparable form
 * †Mystipterus
 * †Mystipterus martini – or unidentified comparable form

N

 * Nannippus jaw.JPG †[[Nannippus]]
 * †Nanotragulus
 * †Nanotragulus loomisi
 * †Nanotragulus ordinatus – type locality for species
 * †Nelumbago
 * †Nelumbago montanum
 * †Neohipparion – type locality for genus
 * †Neohipparion affine – type locality for species
 * †Neonatrix
 * †Neonatrix elongata
 * Neotoma
 * †Neotoma amplidonta – type locality for species
 * Nerodia
 * †Nerodia sipedon
 * Nettion
 * †Nettion greeni – type locality for species
 * †Nexuotapirus
 * †Nexuotapirus marslandensis
 * †Niglarodon
 * †Niglarodon koerneri
 * Nimravus gomphodus.jpg †[[Nimravus]]
 * †Nimravus sectator – type locality for species
 * †Nothodipoides
 * †Nothodipoides planus
 * Notophthalmus
 * †Notophthalmus crassus – type locality for species
 * †Nototamias
 * †Nototamias quadratus
 * †Notropis
 * †Noturus – tentative report

O

 * †Ocajila
 * †Ocajila makpiyahe – type locality for species
 * †Octacodon
 * †Octacodon valens – type locality for species
 * †Ogmophis
 * †Ogmophis miocompactus – type locality for species
 * †Oligoryctes
 * †Oligoryctes altitalonidus
 * †Oligoscalops
 * †Oligoscalops galbreathi
 * †Oligospermophilus
 * †Oligotheriomys
 * †Oligotheriomys magnus – type locality for species
 * Ondatra
 * †Ondatra annectens
 * Onychomys
 * †Onychomys pedroensis
 * †Oreodontoides
 * †Oreodontoides oregonensis
 * Ortalis
 * †Ortalis pollicaris – type locality for species
 * †Osbornodon
 * †Osbornodon sesnoni
 * †Otarocyon
 * †Otarocyon cooki
 * †Otarocyon macdonaldi – type locality for species
 * †Oxetocyon
 * †Oxetocyon cuspidatus – type locality for species
 * Oxydactylus longipes fm.jpg †[[Oxydactylus]]
 * †Oxydactylus lacota – type locality for species
 * †Oxydactylus wyomingensis – or unidentified comparable form

P

 * †Paciculus
 * †Paciculus cedrus – type locality for species
 * †Paciculus montanus – or unidentified comparable form
 * †Paciculus nebraskensis – or unidentified comparable form
 * †Paciculus woodi
 * †Palaeoborus
 * †Palaeoborus rosatus – type locality for species
 * Palaeocastor.jpg †[[Palaeocastor]]
 * †Palaeocastor peninsulatus
 * †Palaeocastor wahlerti
 * †Palaeogale
 * †Palaeogale dorothiae – type locality for species
 * †Palaeogale sectoria
 * †Palaeolagus
 * †Palaeolagus burkei
 * †Palaeolagus haydeni
 * †Palaeolagus hypsodus
 * †Palaeolagus intermedius
 * †Palaeolagus philoi – type locality for species
 * †Palaeonossax – type locality for genus
 * †Palaeonossax senectus – type locality for species
 * †Paleoheterodon
 * †Paleoheterodon tiheni
 * †Parablastomeryx
 * †Parablastomeryx gregorii
 * †Paracrax
 * †Paracrax gigantea – type locality for species
 * †Paracrax wetmorei – type locality for species
 * †Paradaphoenus
 * †Paradaphoenus minimus
 * †Paradaphoenus tooheyi – type locality for species
 * †Paradjidaumo
 * †Paradjidaumo trilophus
 * †Paraenhydrocyon
 * †Paraenhydrocyon robustus
 * †Parahippus
 * †Parahippus cognatus – or unidentified comparable form
 * †Parahippus pawniensis
 * †Parahippus pristinus – type locality for species
 * †Paramerychyus
 * †Paramerychyus harrisonensis
 * †Paramerychyus relictus
 * †Paramys
 * †Paramys relictus
 * †Paranymphaea
 * †Paranymphaea crassifolia
 * †Paranyroca – type locality for genus
 * †Paranyroca magna – type locality for species
 * †Parapliosaccomys
 * †Parapliosaccomys hibbardi – or unidentified related form
 * †Paratomarctus
 * †Paratomarctus euthos
 * †Paratylopus
 * †Paratylopus labiatus
 * †Parictis
 * †Parictis dakotensis – type locality for species
 * †Parictis gilpini – type locality for species
 * †Parictis major – type locality for species
 * †Parictis parvus – type locality for species
 * †Parvericius
 * †Parvericius montanus
 * Peltosaurus.JPG †[[Peltosaurus]]
 * †Peltosaurus granulosus
 * †Pelycomys
 * †Pelycomys placidus
 * †Penetrigonias
 * †Penetrigonias dakotensis
 * †Peraceras
 * †Peraceras superciliosum
 * †Perchoerus
 * †Perchoerus minor
 * †Perchoerus nanus
 * †Perchoerus probus – or unidentified comparable form
 * Perognathus
 * †Perognathus brevidens
 * †Perognathus coquorum – or unidentified comparable form
 * †Perognathus trojectioansrum
 * Peromyscus
 * †Philotrox
 * †Philotrox condoni
 * †Phlaocyon
 * †Phlaocyon minor
 * Phrynosoma
 * †Phrynosoma douglassi
 * †Planera
 * †Planera raynoldsi
 * Platygonus leptorhinus cropped.png of the genus Platygonus. Charles R. Knight (1922).]] †Platygonus
 * †Plesiosorex
 * †Plesiosorex coloradensis
 * †Plesiosorex donroosai – type locality for species
 * †Pleurolicus
 * †Pleurolicus clasoni
 * †Pleurolicus dakotensis – type locality for species
 * †Pleurolicus sulcifrons
 * †Pliauchenia
 * †Pliauchenia magnifontis
 * †Pliogale
 * †Pliogale manka
 * Pliohippus Pernix.jpg †[[Pliohippus]]
 * †Pliohippus pernix
 * †Pliophenacomys
 * †Pliophenacomys osborni – or unidentified comparable form
 * †Pliosaccomys
 * †Pliosaccomys dubius – or unidentified comparable form
 * †Poebrotherium
 * †Poebrotherium wilsoni
 * †Pogonodon
 * †Pogonodon brachyops
 * †Pogonodon cismontanus – type locality for species
 * †Pogonodon eileenae
 * †Problastomeryx
 * †Problastomeryx primus
 * †Procamelus
 * †Procamelus grandis
 * †Procastoroides
 * †Procastoroides sweeti – or unidentified comparable form
 * †Procrax – type locality for genus
 * †Procrax brevipes – type locality for species
 * †Prodipodomys
 * †Prodipodomys idahoensis
 * †Prodipoides
 * †Prodipoides dividerus
 * †Proharrymys
 * †Proharrymys fedti – type locality for species
 * †Proharrymys schlaikjeri
 * †Proharrymys wahlerti
 * †Proheteromys
 * †Proheteromys gremmelsi – type locality for species
 * †Proheteromys ironcloudi – type locality for species
 * †Proheteromys matthewi – type locality for species
 * †Promartes
 * †Promartes gemmarosae
 * †Promartes lepidus – type locality for species
 * †Promartes olcotti
 * Promerycochoerus cropped.png-like oreodont Promerycochoerus both onshore and in the water. Robert Bruce Horsfall (1913).]] †Promerycochoerus
 * †Promerycochoerus carrikeri
 * †Promerycochoerus superbus
 * †Promylagaulus
 * †Promylagaulus riggsi – type locality for species
 * †Proscalops
 * †Proscalops evelynae – type locality for species
 * †Proscalops secundus
 * †Proscalops tertius
 * †Prosciurus
 * †Prosciurus dawsonae
 * †Prosthennops
 * †Prosthennops niobrarensis – or unidentified comparable form
 * †Protapirus
 * †Protapirus obliquidens – type locality for species
 * †Protapirus simplex – type locality for species
 * †Proterix
 * †Proterix bicuspis
 * †Proterix loomisi
 * Knight Protoceras.jpg †[[Protoceras]]
 * †Protoceras celer
 * †Protoceras skinneri – type locality for species
 * †Protohippus
 * †Protohippus supremus – type locality for species
 * †Protolabis
 * †Protolabis heterodontus
 * †Protospermophilus
 * Pseudacris
 * †Pseudacris clarki – or unidentified comparable form
 * †Pseudaelurus
 * †Pseudhipparion
 * †Pseudhipparion gratum
 * †Pseudhipparion retrusum
 * †Pseudoblastomeryx
 * †Pseudoblastomeryx advena
 * †Pseudograptemys
 * †Pseudograptemys inornata – type locality for species
 * Pseudoprotoceras fossil.jpg †[[Pseudoprotoceras]]
 * †Pseudoprotoceras longinaris
 * †Pseudoprotoceras minor
 * †Pseudotheridomys
 * †Pseudotrimylus
 * †Pseudotrimylus dakotensis
 * †Pterogaulus
 * †Pterygoboa – type locality for genus
 * †Pterygoboa miocenica – type locality for species

Q

 * †Quadrodens
 * †Quadrodens wilsoni – type locality for species
 * Querquedula
 * †Querquedula integra – type locality for species

R

 * †Rana
 * North-American-bullfrog1.jpg †[[Rana catesbeiana]]
 * †Rana pipiens
 * Reithrodontomys
 * †Reithrodontomys moorei
 * Rhineura
 * †Rhineura hatcherii – type locality for species
 * †Rhineura sepultura – type locality for species
 * †Russellagus
 * †Russellagus vonhofi – or unidentified comparable form

S

 * Salvadora
 * †Salvadora paleolineata
 * †Sanctimus
 * †Sanctimus stuartae – type locality for species
 * †Scalopoides
 * †Scalopoides isodens – or unidentified comparable form
 * Scaphiopus
 * †Scaptohyus
 * †Scaptohyus altidens – type locality for species
 * †Schaubeumys
 * †Schaubeumys clivosus
 * †Schaubeumys galbreathi
 * †Schaubeumys grangeri – type locality for species
 * †Schizodontomys
 * †Schizodontomys harkseni
 * †Scottimus
 * †Scottimus exiguus
 * †Scottimus lophatus
 * †Semotelus – tentative report
 * †Sespia
 * †Sespia nitida – type locality for species
 * †Sinclairella
 * †Sinclairella dakotensis
 * Sorex
 * †Sorex cinereus
 * Spea
 * †Spea neuter – type locality for species
 * Spermophilus
 * Stegomastodon mirificus - Smithsonian.JPG †[[Stegomastodon]]
 * †Stegomastodon mirificus
 * †Steneofiber
 * †Steneofiber fossor
 * †Steneofiber gradatus
 * †Stibarus
 * †Stibarus obtusilobus
 * †Stibarus quadricuspis
 * Strix
 * †Strix dakota – type locality for species
 * Stylemys (1).jpg †[[Stylemys]]
 * †Stylemys nebrascensis
 * †Subhyracodon
 * †Subhyracodon mitis
 * †Subhyracodon occidentalis
 * †Sunkahetanka
 * †Sunkahetanka geringensis
 * Sylvilagus
 * †Sylvilagus floridanus

T

 * Tapirus
 * Teleoceras Horsfall cropped.jpg †[[Teleoceras]]
 * †Teleoceras major
 * †Teleodus – type locality for genus
 * †Teleodus avus – type locality for species
 * †Temperocastor
 * †Temperocastor valentinensis
 * †Tenudomys
 * †Tenudomys macdonaldi – type locality for species
 * Thamnophis
 * †Thamnophis sirtalis
 * †Thinohyus
 * Thomomys
 * †Tisisthenes
 * †Tisisthenes parvus
 * Titanotylopus nebraskensis skeleton.jpg †[[Titanotylopus]]
 * †Trigenicus
 * †Trigenicus profectus
 * †Trigonias
 * †Trigonias osborni
 * †Trigonias wellsi – type locality for species
 * †Trilaccogaulus
 * †Trilaccogaulus ovatus
 * †Triletes
 * †Triletes velus – type locality for species
 * †Tylionomys
 * †Tylionomys woodi
 * Tympanuchus
 * †Tympanuchus stirtoni – type locality for species
 * †Tyrannomys
 * †Tyrannomys harkseni

U

 * †Ursavus
 * †Ustatochoerus
 * †Ustatochoerus medius

W

 * †Wilsoneumys – tentative report
 * †Wilsoneumys planidens
 * †Wilsonosorex
 * †Wilsonosorex bateslandensis
 * †Woodoceras – type locality for genus
 * †Woodoceras brachyops – type locality for species

X

 * †Xenochelys
 * †Xenochelys formosa – type locality for species

Z

 * Zapus hudsonius.jpg [[Zapus]]
 * †Zapus sykesae
 * Zelkova
 * †Zelkova planeroides