List of the Cenozoic life of Texas

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

A

 * †Abdounia
 * †Abdounia enniskilleni
 * †Abdounia recticona
 * Abra
 * †Abra nitens
 * †Abra petropolitana
 * Acanthocardia aculeata 001.jpg [[Acanthocardia]]
 * †Acanthocardia tuomeyi
 * Acar
 * †Acar aspera
 * Acirsa
 * †Acirsa whitneyi
 * †Aclistomycter
 * †Aclistomycter dunagani – type locality for species
 * †Aclistomycter middletoni – type locality for species
 * Acris
 * †Acris crepitans
 * Acteocina cropped.png [[Acteocina]]
 * Acteon
 * †Acteon idoneus
 * †Acteon pomilis
 * †Acteon pomilius
 * †Acteon punctatus
 * Adeonellopsis – tentative report
 * †Adjidaumo
 * †Adjidaumo minutus – or unidentified comparable form
 * Admetula
 * †Admetula irregularis – type locality for species
 * Adrana
 * †Adrana aldrichiana
 * Aedes
 * †Aelurodon
 * †Aelurodon ferox
 * †Aelurodon taxoides
 * Aepycamelus Alticamelus hharder.jpg †[[Aepycamelus]]
 * Agaronia
 * †Agaronia bombylis
 * †Agaronia media
 * †Agaronia mediavia
 * Agkistrodon
 * †Agriocharis
 * †Agriocharis anza
 * †Agriochoerus
 * †Agriochoerus antiquus
 * †Agriotherium
 * †Agriotherium schneideri
 * †Agrobuccinium
 * †Agrobuccinum
 * †Agrobuccinum mansfieldi
 * †Aguascalientia
 * †Aguispira
 * †Aguispira alternata
 * Akera
 * †Akera texana
 * †Alforjas
 * †Alforjas taylori – type locality for species
 * Aliculastrum
 * †Alilepus
 * †Alilepus wilsoni
 * †Allaeochelys – or unidentified comparable form
 * Alligator
 * †Alligator mississipiensis
 * †Alligator mississippiensis
 * Alligator olseni.jpg †[[Alligator olseni]]
 * †Allognathosuchus
 * †Allomorone
 * †Allomorone burlesonis
 * †Allophaiomys
 * †Allophaiomys pliocaenicus
 * †Altaspiratella
 * †Altaspiratella bearnensis – tentative report
 * Alvania
 * †Alveinus
 * †Alveinus minutus
 * Amaea
 * †Amaea macula – type locality for species
 * †Amaea texana – type locality for species
 * †Amaurellina
 * †Amaurellina plummeri – type locality for species
 * †Amaurellina singleyi
 * †Amblema
 * †Amblema plicata
 * †Ambystoma
 * †Ambystoma tigrinum
 * Amebelodon fricki.jpg †[[Amebelodon]]
 * †Amebelodon britti
 * †Amebelodon floridanus
 * †Amebelodon fricki – or unidentified comparable form
 * †Ameiurus
 * †Amentogerdiopollenites – type locality for genus
 * †Amentogerdiopollenites oligocenensis – type locality for species
 * †Amentoplexipollenites – type locality for genus
 * †Amentoplexipollenites catahoulaensis – type locality for species
 * Amnicola
 * †Amnicola integra
 * †Amphicyon
 * †Amphicyon longiramus
 * †Amphicyon pontoni
 * Machairodus giganteus 1.jpg †[[Amphimachairodus]]
 * †Amphimachairodus coloradensis – or unidentified comparable form
 * Amphiuma
 * †Amphiuma antica – type locality for species
 * †Amplobalanus – type locality for genus
 * †Amplobalanus texensis – type locality for species
 * †Ampullina
 * †Ampullina dumblei
 * †Ampullina recurva
 * Amuletum
 * †Amuletum curvocostatum
 * Amusium
 * †Amusium zinguli – type locality for species
 * †Amynodon
 * †Amynodon advenus
 * †Amynodontopsis
 * †Amynodontopsis bodei
 * Anadara
 * †Anadara vaughani
 * Anancus NT small.jpg †[[Anancus]]
 * †Anancus defloccatus – type locality for species
 * †Anancus orarius – type locality for species
 * †Anchitheriomys
 * †Anchitherium
 * †Anchitherium navasotae – type locality for species
 * Ancilla
 * †Ancilla staminea – type locality for species
 * †Ancilla staminea punctulifera
 * †Angelarctocyon
 * †Angelarctocyon australis – type locality for species
 * †Angulithes
 * †Angulithes elliotti
 * †Anilioides
 * †Anilioides nebraskensis – or unidentified comparable form
 * †Anisaster
 * †Anisaster mossomi
 * Sugar apple with cross section.jpg †[[Annona]]
 * †Annona ampla
 * Anodontia
 * †Anodontia reklawensis – type locality for species
 * †Anomalofusus
 * Anomia
 * †Anomia argentaria
 * †Anomia ephippioides
 * †Anomia lisbonensis
 * Antalis
 * †Antalis minutistriatum
 * †Antalis mississippiense
 * †Antalis palmerae – type locality for species
 * Anthonomus – tentative report
 * †Antiguastrea
 * †Antiguastrea cellulosa
 * Antillophos
 * †Antillophos multilineatum – type locality for species
 * Antrozous
 * †Antrozous pallidus
 * †Aphelops
 * †Aphelops malacorhinus
 * †Aphelops megalodus
 * †Aphelops mutilus
 * †Aplexia
 * †Aplexia hypnorum
 * Aplodinotus
 * †Aplodinotus grunniens
 * †Apocynophyllum
 * †Apocynophyllum wilcoxense
 * †Apternodus
 * †Apternodus iliffensis
 * Aquila
 * †Aquila chrysaetos
 * Arca
 * †Arca petropolitana
 * †Archaeohippus
 * †Archaeohippus blackbergi – type locality for species
 * †Archaeolagus
 * †Archaeolagus acaricolus – or unidentified comparable form
 * †Archaeolagus buangulus – type locality for species
 * Archaeotherium.jpg †[[Archaeotherium]]
 * †Archaeotherium mortoni – or unidentified comparable form
 * Architectonica
 * †Architectonica aldrichi – type locality for species
 * †Architectonica alveatum
 * †Architectonica amoena
 * †Architectonica bellensis
 * †Architectonica bellistriata
 * †Architectonica bimixta
 * †Architectonica elaborata
 * †Architectonica fimbriaea – type locality for species
 * †Architectonica geminicostata – type locality for species
 * †Architectonica huppertzi
 * †Architectonica meekana
 * †Architectonica ornata
 * †Architectonica phoenicea
 * †Architectonica planiformis
 * †Architectonica reklawensis – type locality for species
 * †Architectonica texcarolina
 * †Architectonica vespertina
 * Arcopagia
 * †Arcopagia trumani
 * †Arctocyon
 * †Arctocyon mumak – or unidentified comparable form
 * ArctodusSimusReconstruct.jpg †[[Arctodus]]
 * †Arctodus simus
 * †Arctonasua
 * †Arctonasua gracilis – or unidentified comparable form
 * †Ardynomys
 * †Ardynomys occidentalis
 * Argobuccinum
 * Argyrotheca
 * †Argyrotheca powersi
 * Arius – or unidentified comparable form
 * Arizona
 * †Arizona elegans
 * †Arretotherium
 * †Arretotherium acridens
 * †Artocarpus
 * †Artocarpus lessigiana
 * Astarte
 * Asthenotoma
 * †Asthenotoma eximia
 * †Astrohippus
 * †Astrohippus ansae – type locality for species
 * †Astrohippus stockii
 * Athleta ficulina 01.JPG [[Athleta]]
 * †Athleta dalli
 * †Athleta kerensensis
 * †Athleta limopsis
 * †Athleta limposis
 * †Athleta lisbonensis
 * †Athleta olssoni
 * †Athleta petrosa
 * †Athleta rugatus
 * †Athleta stenzeli
 * †Athleta symmetricus
 * †Athleta texanus
 * †Athleta wheelockensis
 * †Athletea
 * †Athletea petrosus
 * Atlanta
 * †Atlanta eocenica
 * †Atopomys
 * †Atopomys texensis
 * Atractosteus
 * †Atractosteus spatula
 * †Atractosteus tristoechus – tentative report
 * Atrina
 * †Atrina cawcawensis
 * †Atrina gardnerae
 * Aturia alabamensis by Apokryltaros.png †[[Aturia]]
 * †Aturia brazoensis
 * †Aturia laticlavia
 * †Aturia triangula
 * †Aturia turneri
 * Atys
 * †Atys atysopsis
 * †Atys trapaquara
 * †Aulolithomys
 * †Aulolithomys bounites
 * †Australocamelus
 * †Australocamelus orarius – type locality for species
 * †Auxontodon
 * †Awateria
 * †Awateria retifera

B

 * †Baioconodon
 * Baiomys
 * †Baiomys rexroadi
 * †Baiotomeus
 * †Baiotomeus douglassi
 * Bairdia
 * †Bairdia oviformis
 * Cup coral064.jpg [[Balanophyllia]]
 * †Balanophyllia augustinensis – type locality for species
 * †Balanophyllia desmophyllum
 * †Balanophyllia irrorata
 * †Balanophyllia ponderosa
 * Balanus
 * Balcis
 * †Balcis exilis
 * †Balcis tenua
 * †Balcis wheeleri
 * Carditidae - Venericardia ameliae.JPG †[[Baluchicardia]]
 * †Baluchicardia bulla
 * †Baluchicardia hesperia
 * †Baluchicardia moa
 * †Baluchicardia whitei
 * †Baluchicardia wilcoxensis
 * Bankia
 * †Bankia petalus – type locality for species
 * †Baptemys – or unidentified comparable form
 * Barbatia
 * †Barbatia cuculloides
 * †Barbatia deusseni
 * †Barbatia ludoviciana
 * †Barbatia reklawensis – type locality for species
 * †Barbatia salebrosus – type locality for species
 * †Barbatia uxorispalmeri
 * Barbourofelis fricki.JPG †[[Barbourofelis]]
 * †Barbourofelis whitfordi
 * Bassariscus
 * †Bassariscus casei
 * Bathyarca
 * †Bathyarca claibornica – type locality for species
 * †Bathygenys
 * †Bathygenys reevesi – type locality for species
 * Bathytoma
 * †Bathytoma nonplicata – or unidentified comparable form
 * Bathytormus
 * †Bathytormus flexurus
 * †Batrachosauroides
 * †Batrachosauroides dissimulans
 * †Bauzaia – type locality for genus
 * †Bauzaia lamberi – type locality for species
 * †Bauzaia melrosensis
 * †Bauzaia mucronata
 * †Beckiasorex
 * †Beckiasorex hibbardi
 * Bela – report made of unidentified related form or using admittedly obsolete nomenclature
 * †Bela rebeccae
 * †Belosaepia
 * †Belosaepia pennae – type locality for species
 * †Belosaepia ungula
 * †Belosaepia ungulata
 * †Belosepia
 * †Belosepia pennae – type locality for species
 * †Bensonomys
 * †Bensonomys coffeyi
 * †Beretra
 * †Beretra ornatula – or unidentified related form
 * Bison
 * †Bison alaskensis
 * †Bison antiquus
 * Bison latifrons fossil buffalo.jpg †[[Bison latifrons]]
 * Bittiolum – report made of unidentified related form or using admittedly obsolete nomenclature
 * †Bittiolum webbi
 * Bittium
 * †Bittium anita
 * †Bittium estellense
 * †Bittium estellensis
 * †Bittium henryleai
 * †Bittium ridgei – type locality for species
 * †Bittium tresquatrum – type locality for species
 * †Blancocamelus
 * †Blancocamelus meadei
 * †Blancotherium – type locality for genus
 * †Blancotherium buckneri – type locality for species. Formerly known as Gnathabelodon buckneri.
 * Blarina
 * †Blarina brevicauda – or unidentified comparable form
 * †Blastomeryx
 * †Blastomeryx vigoratus – type locality for species
 * Boavus idelmani.JPG †[[Boavus]] – tentative report
 * †Boavus affinis
 * †Bolis
 * †Bolis enterogramma
 * †Bombacacidites
 * †Bombacacidites paulus
 * †Bomburia – or unidentified comparable form
 * †Bonellitia
 * †Bonellitia bastropensis
 * †Bonellitia parilis
 * †Borealosuchus
 * Bornia
 * †Bornia prima
 * †Bornia zapataensis
 * Borophagus cropped.png genus Borophagus preying on a camel. Jay Matternes (1964).]] †Borophagus
 * †Borophagus diversidens
 * †Borophagus hilli – type locality for species
 * †Borophagus pugnator – or unidentified comparable form
 * †Borophagus secundus
 * †Bouromeryx
 * †Bouromeryx submilleri
 * †Boverisuchus
 * †Boverisuchus vorax – or unidentified comparable form
 * Brachidontes
 * †Brachidontes alabamensis
 * †Brachidontes saffordi
 * †Brachidontes texanus
 * Brachiodontes
 * †Brachyerix – tentative report
 * †Brachyerix hibbardi – type locality for species
 * †Brachyhyops
 * †Brachyhyops viensis
 * †Brachyhyops wyomingensis
 * †Brachyopsigale
 * †Brachyopsigale dubius
 * Brachyrhynchocyon cropped.png †[[Brachyrhynchocyon]]
 * †Brachyrhynchocyon dodgei
 * †Brauzaia
 * †Brauzaia melrosensis
 * †Brazosiella – type locality for genus
 * †Brazosiella kokeni – type locality for species
 * †Brazosiella moselevi
 * †Brazosiella moseleyi – type locality for species
 * Bregmaceros
 * †Bregmaceros troelli – type locality for species
 * Brissus
 * †Brissus exiguus
 * †Bryozoan
 * Bufo
 * Bufo cognatus1.jpg (formerly Bufo cognatus), or Great Plains toad]] †Bufo cognatus''
 * †Bufo woodhousei
 * †Buisnictis
 * †Buisnictis breviramus
 * Bulimulus
 * †Bulimulus dealbatus
 * Bullia
 * †Bullia altilis – type locality for species
 * †Bullia ancillops
 * †Bullia ellipticum – type locality for species
 * †Bullia tenera
 * †Bulovia
 * †Bulovia weisbordi

C

 * Cadulus
 * †Cadulus abruptus
 * †Cadulus aldrichi
 * †Cadulus bisissura – type locality for species
 * †Cadulus ouachitensis
 * †Cadulus phoenicea
 * †Cadulus subcoarcuatus
 * †Cadulus turgidus
 * Caecum – or unidentified comparable form
 * †Caenolambda
 * †Caenolambda jepseni
 * Caestocorbula
 * †Caestocorbula wailesiana
 * †Calamagras
 * †Calamagras weigeli
 * Calappidae - Calappilia mainii.JPG †[[Calappilia]]
 * †Calappilia diglypta
 * †Calippus
 * †Calippus cerasinus – or unidentified comparable form
 * †Calippus circulus – type locality for species
 * †Calippus large informal
 * †Calippus martini
 * †Calippus placidus
 * †Calippus proplacidus
 * †Calippus regulus – type locality for species
 * Callianassa
 * †Callianassa brazoensis
 * †Callianassa wechesensis
 * Callucina
 * †Callucina sabelli
 * †Calorhadia
 * †Calorhadia bella
 * †Calorhadia compsa
 * †Calorhadia diminutia – type locality for species
 * †Calorhadia opulenta
 * Calyptraea
 * †Calyptraphorus
 * †Calyptraphorus aldrichi
 * †Calyptraphorus popenoe
 * †Calyptraphorus trinodiferus
 * †Calyptraphorus velatus
 * Camelops hesternus.jpg †[[Camelops]]
 * †Camelops hesternus – type locality for species
 * †Camelops minidokae
 * †Camptoceratops
 * †Camptoceratops priscus – type locality for species
 * Cancellaria
 * †Cancelrana
 * †Cancelrana finexa
 * Candona
 * †Candona lactea – or unidentified comparable form
 * †Candona nyensis
 * Canis
 * †Canis armbrusteri
 * †Canis dirus
 * †Canis edwardii
 * †Canis latrans
 * †Canis lepophagus – type locality for species
 * Cantharus
 * †Cantharus casteri
 * Capromeryx minor p1350725.jpg †[[Capromeryx]]
 * †Capromeryx furcifer
 * Capulus
 * †Capulus americanus
 * Carapus
 * †Carapus smithvillensis – type locality for species
 * Carcharhinus
 * †Carcharhinus gibbesi
 * Cardiomya
 * †Cardiomya fredsmithi – type locality for species
 * Cardium (bivalve)
 * †Caricella
 * †Caricella cherokeensis
 * †Caricella demissa
 * †Caricella heilprini
 * †Caricella stenzeli
 * †Carpocyon
 * †Carpocyon robustus
 * †Carpolithus
 * Carychium
 * †Carychium exiguum
 * Caryocorbula
 * †Caryocorbula cappa
 * †Caryocorbula coloradoensis
 * †Caryocorbula deusseni
 * †Caryocorbula engonatoides
 * †Caryocorbula kennedyi
 * †Caryocorbula marquezensis – type locality for species
 * Caryophyllia2610.jpg [[Caryophyllia]]
 * †Caryophyllia constricta – type locality for species
 * †Caryophyllia mediavia – type locality for species
 * †Caryophyllia texana – type locality for species
 * Castor
 * †Castor canadensis
 * Catagonus
 * †Caveola
 * †Caveola ostium – type locality for species
 * Celleporaria
 * †Celleporaria granulosa
 * Celtis
 * †Centetodon
 * †Centetodon chadronensis
 * †Centetodon pulcher
 * Centropomus – tentative report
 * Ceratobulimina
 * †Ceratobulimina eximia
 * Nsthornedgopher-hlmwh-rbh13.jpg †[[Ceratogaulus]]
 * †Ceratogaulus anecdotus – or unidentified comparable form
 * †Cerdocyon
 * †Cerdocyon texanus – type locality for species
 * Cerithiella
 * †Cerithiella terebropsis
 * †Cerithioderma
 * †Cerithioderma primum
 * Cerithiopsis
 * Cerithium – tentative report
 * Chaetodipus
 * †Chaetodipus hispidus
 * Chama
 * †Chama taylorensis – type locality for species
 * Charina
 * †Charina prebottae
 * †Charophyte
 * †Charophyte oogonia
 * Chasmaporthetes fossil cropped.png †[[Chasmaporthetes]]
 * †Chasmaporthetes ossifragus
 * †Chiromyoides
 * †Chiromyoides minor – or unidentified comparable form
 * †Chiromyoides potior
 * Chironomus
 * †Chironomus kirklandi – type locality for species
 * Chlamys
 * †Chlamys beverlyi
 * †Chlamys burlesonensis
 * †Chriacus
 * †Chriacus baldwini
 * †Cimolodon
 * †Cimomia
 * †Cimomia vaughani – type locality for species
 * Cirsotrema
 * †Cirsotrema nassulum
 * Cissus
 * †Cissus pulcherrima
 * †Claibornichthys
 * †Claibornichthys troelli – type locality for species
 * Clavilithes noae 01.JPG [[Clavilithes]]
 * †Clavilithes acus – type locality for species
 * †Clavilithes chamberlaini
 * †Clavilithes kennedyanus
 * †Clavilithes parvetorbis – type locality for species
 * †Clavilithes penrosei
 * †Clavilithes regexus
 * †Clavilithes texanus
 * Clavus – tentative report
 * †Clavus dipta
 * †Cleonidius
 * †Cleonidius channingensis – type locality for species
 * †Cleonidius ritablancaensis – type locality for species
 * Clithrocytheridea
 * †Clithrocytheridea garretti
 * Closia
 * †Closia semen
 * †Closia semenoides
 * Clypeaster
 * †Clypeaster oxybaphon – or unidentified comparable form
 * †Clypeaster rogersi
 * †Cochlefusia
 * †Cochlefusia serrae – type locality for species
 * Cochlespira radiata 001.jpg [[Cochlespira]]
 * †Cochlespira bastropensis
 * †Cochlespira bella
 * †Cochlespira columbaria
 * †Cochlespira engonata
 * †Cochlespira greggi – tentative report
 * †Cochlespirella
 * †Cochlespirella nana
 * †Cochlespiropsis
 * †Cochlespiropsis engonata
 * Cochliolepis
 * †Cochliolepis palaeocenica – type locality for species
 * Cochlodesma
 * †Cochlodesma howei – or unidentified comparable form
 * †Cochlodesma ovalis – type locality for species
 * †Colodon
 * †Colodon stovalli
 * Coluber
 * Coluber constrictor anthicus.jpg †[[Coluber constrictor]]
 * Colubraria
 * †Colubraria cedri
 * Columbella – report made of unidentified related form or using admittedly obsolete nomenclature
 * †Columbella punctostriata
 * †Colwellia
 * †Colwellia bilineata – type locality for species
 * †Combretum
 * †Combretum bartonii
 * Cominella – or unidentified comparable form
 * †Cominella pachecoi
 * Conomitra
 * †Conomitra texana
 * Conopeum
 * †Conopeum damicornis
 * †Contracuparius – type locality for genus
 * †Contracuparius huntsvillensis – type locality for species
 * †Contracuparius robustus – type locality for species
 * Conus pelagicus Brocchi 1814Pliocene Cyprus.jpg [[Conus]]
 * †Conus sauridens – type locality for species
 * †Conus smithvillensis
 * †Copemys
 * †Coptostoma
 * †Coptostoma rameum
 * †Coptostoma ulmulum
 * Corbicula
 * †Corbicula texana
 * Corbula
 * †Corbula alabamiensis
 * †Corbula augustae
 * †Corbula cappa
 * †Corbula coloradoensis
 * †Corbula kennedyi
 * †Corbula marquezensis – type locality for species
 * †Corbula milium
 * †Corbula texana – type locality for species
 * Ashfall Fossil Beds - Teleoceras and Cormohipparion.jpg †[[Cormohipparion]]
 * †Cormohipparion fricki – type locality for species
 * †Cormohipparion goorisi
 * †Cormohipparion ingenuum – type locality for species
 * †Cormohipparion skinneri – type locality for species
 * †Cornulina
 * †Cornulina armigera
 * †Cornulina dalli
 * †Cornulina minax – type locality for species
 * †Coronia
 * †Coronia alternata
 * †Coronia anacona
 * †Coronia childreni
 * †Coronia genitiva
 * †Coronia margaritosa
 * †Coronia mediavia
 * †Coronia nodoidea
 * †Coronia nucleata
 * †Coronia ostrarupis
 * †Coronia sublerchi
 * †Coronia taylori – type locality for species
 * †Corvina
 * †Corvina intermedia
 * Corvus
 * †Corvus brachyrhynchos
 * †Coryphodon
 * †Coryphodon armatus
 * Cranioceras unicornis life restoration.jpg Cranioceras, a relative of modern deer, with anachronistic human to scale]] †Cranioceras
 * †Cranioceras teres – type locality for species
 * Crassatella
 * †Crassatella antestriata
 * †Crassatella gabbi
 * †Crassatella ioannes
 * †Crassatella texalta
 * †Crassatella texana
 * †Crassatella trapaquara
 * Crassinella
 * †Crassinella aldrichi
 * †Crassinella minor
 * †Crassinella pteleina
 * Crassostrea gigantissima (Finch, 1824).JPG [[Crassostrea]]
 * †Crassostrea amichel
 * †Crassostrea contracta
 * †Crassostrea frionis
 * Cratogeomys
 * †Cratogeomys castanops
 * Crenella
 * †Crenella margaritacea
 * †Crenodonta
 * †Crenodonta perplicata
 * †Creonella
 * Creseis
 * †Cristellaria
 * †Cristellaria orelliana
 * †Cristellaria rotulata
 * †Cristellaria torrida
 * Crotalus
 * †Crotalus atrox
 * ZollmanTimberRattlesnake.jpg †[[Crotalus horridus]]
 * Crotaphytus
 * †Crotaphytus collaris
 * †Crotaphytus reticulatus
 * †Cryptochorda
 * †Cryptochorda eureia
 * †Cryptochorda stenostoma
 * Cryptotis
 * †Cryptotis parva
 * Ctenoides
 * †Ctenoides bastropensis
 * †Cubitostrea
 * †Cubitostrea divaricata
 * †Cubitostrea lisbonensis
 * †Cubitostrea petropolitana
 * †Cubitostrea sanctiaugustini
 * †Cubitostrea sellaeformis
 * †Cubitostrea smithvillensis
 * Cucullaea labiata 3.JPG [[Cucullaea]]
 * †Cucullaea kaufmanensis
 * †Cucullaea macrodonta
 * †Cucullaea saffordi
 * †Cucullaea texana
 * Culex
 * Cuna
 * †Cuneocorbula
 * †Cuneocorbula subengonata
 * †Cupanites
 * †Cupanites formosus
 * †Cupidinimus
 * Cuspidaria
 * †Cuspidaria grandis
 * Cuvieronius.jpg †[[Cuvieronius]]
 * Cyclammina
 * Cyclostremiscus
 * †Cyclostremiscus axacuus
 * †Cyclostremiscus dalli
 * †Cyclostremiscus exacuus
 * †Cyclostremiscus sylvaerupis
 * Cylichna
 * †Cylichna bicarinata – type locality for species
 * †Cylindracanthus
 * †Cylindrodon
 * Cyllene – or unidentified comparable form
 * †Cyllene bellana
 * Cynarctoides fossil cropped.png †[[Cynarctoides]]
 * †Cynarctoides whistleri
 * †Cynarctus
 * †Cynarctus crucidens
 * Cynomys
 * †Cynomys ludovicianus
 * †Cynomys spenceri
 * Cypraea
 * Cypraedia
 * †Cypraedia subcancellata – type locality for species
 * †Cypraeorbis
 * †Cypraeorbis bulbus – type locality for species
 * Cypridopsis
 * †Cypridopsis vidua
 * Cythara
 * †Cythara schotti
 * Cythere
 * †Cythere claiborniana
 * †Cythere evergreenica
 * †Cythere leeana
 * †Cythere orelliana
 * †Cythere texana
 * †Cythereis
 * †Cythereis bursilloides
 * †Cythereis davidwhitei
 * †Cythereis elmana
 * †Cythereis elongata – type locality for species
 * †Cythereis fragillissima – type locality for species
 * †Cythereis hilgardi
 * †Cythereis linospinosa – type locality for species
 * †Cythereis montgomeryensis
 * †Cythereis quinquespinosa – type locality for species
 * †Cythereis reklawensis – type locality for species
 * †Cythereis russelli
 * †Cythereis sinuata – type locality for species
 * †Cythereis smithvillensis – type locality for species
 * †Cythereis spinosa – type locality for species
 * †Cythereis splendens – type locality for species
 * †Cythereis uptonensis – type locality for species
 * †Cythereis washburni – type locality for species
 * Cytherella
 * †Cytherella fimbricinctus – type locality for species
 * †Cytherella texana
 * Cytheridea
 * †Cytheridea compressa – type locality for species
 * †Cytheridea habropapillosa – type locality for species
 * †Cytheridea mulleri
 * †Cytheridea subovata – type locality for species
 * †Cytheridea subpyriformis – type locality for species
 * Cytheropteron
 * †Cytheropteron minutum – type locality for species
 * †Cytheropteron virgineum

D

 * †Dakotaophis
 * †Dakotaophis greeni
 * †Daphoenictis
 * †Daphoenodon
 * †Daphoenodon notionastes
 * †Daphoenus
 * †Daphoenus lambei – or unidentified comparable form
 * Dasyatis
 * Dasypus
 * D. bellus jaw.png †[[Dasypus bellus]]
 * †Delahomeryx
 * †Delahomeryx browni – type locality for species
 * Dentalium
 * †Dentalium mediaviense
 * †Dentalium palmerae – type locality for species
 * †Dentalium thalloides – or unidentified related form
 * Dermatemys
 * †Desmatippus
 * †Desmatippus texanus
 * †Diablomomys – type locality for genus
 * †Diablomomys dalquesti – type locality for species
 * †Diaphyodus
 * †Diaphyodus wilsoni – type locality for species
 * †Dibelodon
 * †Dibelodon praecursor
 * Subhyracodon tridactylus.jpg Diceratherium. Robert Bruce Horsfall (1913).]] †Diceratherium
 * †Diceratherium annectens
 * †Diceratherium armatum
 * Didelphis
 * †Didelphis marsupialis
 * †Dillenites
 * †Dillenites microdentatus
 * †Dillenites texensis
 * †Dinofelis
 * †Dinofelis palaeoonca
 * †Dinohippus
 * †Dinohippus interpolatus – type locality for species
 * †Dinohippus mexicanus – or unidentified comparable form
 * †Dinohyus
 * †Dinohyus hollandi
 * Diplodonta
 * †Diplodonta anterproductus
 * †Diplodonta petropolitana
 * †Diplodonta satex
 * Diplotaxis – or unidentified comparable form
 * Dipodomys
 * †Dipodomys merriami
 * †Dipodomys ordii
 * †Dipodomys pattersoni – type locality for species
 * †Dipodomys spectabilis
 * †Dirocerithium
 * †Dirocerithium wechesense
 * †Discotrochus
 * †Discotrochus orbignianus
 * †Discradisca
 * †Discradisca littigensis
 * Disonycha
 * †Dolicholatirus
 * †Dolicholatirus harrisi
 * †Dolicholatirus leaensis
 * †Dolicholatirus obtusus
 * †Dolicholatirus singleyi
 * †Domenginella
 * †Domenginella ridgei – type locality for species
 * †Domingella
 * †Domingella ridgei – type locality for species
 * Dorsanum
 * †Dorsanum – type locality for species informal
 * †Dorsanum scalatum
 * †Drepanomeryx
 * †Drepanomeryx falciformis
 * †Dryophyllum
 * †Dryophyllum tennesseensee
 * Duchesneodus-skull.png †[[Duchesneodus]]
 * †Duchesneodus uintensis

E

 * †Eburneopecten
 * †Eburneopecten scintillatus
 * Echmatemys stevensoniana AMNH 6084.jpg †[[Echmatemys]]
 * †Ectypodus
 * †Ectypodus musculus
 * †Edaphocyon
 * †Edaphocyon pointblankensis – type locality for species
 * †Ekokenia
 * †Ekokenia eporrecta
 * Elaphe
 * †Elaphe guttata
 * †Elaphe nebraskensis
 * †Elaphe obsoleta
 * Eleutherodactylus
 * †Eleutherodactylus augusti
 * †Ellipsechinus
 * †Ellipsechinus prisca
 * †Ellisella
 * Emarginula striatula (top view).JPG [[Emarginula]] – or unidentified comparable form
 * Endochironomus
 * Endopachys
 * †Endopachys maclurii
 * Engelhardia
 * †Engelhardia trinitiensis – type locality for species
 * †Eoancilla
 * †Eoancilla hordea – type locality for species
 * †Eocypraea
 * †Eocypraea estellensis
 * †Eocythara – type locality for genus
 * †Eocythara lineata – type locality for species
 * †Eocythara texanum – type locality for species
 * †Eodichroma – type locality for genus
 * †Eodichroma mirifica – type locality for species
 * †Eodrilla
 * †Eodrilla texana
 * †Eodrillia
 * †Eodrillia texana
 * †Eodrillia texanopsis
 * †Eomellivora
 * †Eopleurotoma
 * †Eopleurotoma bimoniata
 * †Eopleurotoma lisboncola
 * †Eopleurotoma nodocarinata
 * †Eosolea – type locality for genus
 * †Eosolea texana – type locality for species
 * †Eosurcula
 * †Eosurcula moorei – type locality for species
 * †Eosurcula superpons
 * †Eotylopus
 * †Eotylopus reedi – or unidentified comparable form
 * Epicauta
 * Epicyon haydeni skeleton.jpg †[[Epicyon]]
 * †Epicyon haydeni
 * †Epicyon saevus
 * †Epihippus
 * †Epihippus gracilis
 * Epilucina
 * Episcynia
 * †Episcynia bastropensis
 * Episiphon
 * †Episiphon gracilis – type locality for species
 * Epitonium
 * †Epitonium cookii
 * †Epitonium dolosum
 * †Epitonium multiliniferum
 * †Epitriplopus
 * Eponides
 * †Eponides patelliformis
 * †Eponides texana
 * Eptesicus
 * †Eptesicus fuscus
 * †Eptesicus hemphillensis – type locality for species
 * Equus
 * †Equus alaskae – or unidentified comparable form
 * †Equus complicatus
 * †Equus conversidens
 * †Equus francisci – type locality for species
 * †Equus giganteus
 * †Equus idahoensis
 * †Equus midlandensis
 * †Equus scotti – type locality for species
 * †Equus semiplicatus
 * Equus simplicidens UMNH.jpg †[[Equus simplicidens]]
 * Erethizon
 * †Erethizon dorsatum
 * †Eucheilodon
 * †Eucheilodon reticulata
 * †Eucyon
 * †Eucyon davisi
 * Eucytherura
 * †Eucytherura claibornensis – type locality for species
 * Eulima
 * †Eulima extremis
 * †Eulima tenaxa
 * Eumeces obsoletus1 cropped.jpg (formerly Eumeces obsoletus), or Great Plains skink]] Eumeces''
 * †Eumeces fasciatus
 * †Eumeces miobsoletus – type locality for species
 * †Eumeces obsoletus
 * †Euonymus
 * †Euonymus glanduliferus
 * Eupleura
 * †Eupleura morula
 * †Euryochetus
 * †Euryochetus punctatum – type locality for species
 * Eurytellina
 * †Eurytellina milamensis – type locality for species
 * †Eurytellina mooreana
 * †Eurytellina papyria
 * Euspira catena.jpg [[Euspira]]
 * †Euspira aldrichi
 * †Euspira jacksonensis
 * †Euspira marylandica
 * †Euspira perspecta
 * †Eutrephoceras
 * †Eutrephoceras reesidei
 * †Eutypomys
 * †Eutypomys inexpectatus – type locality for species
 * †Exilia
 * †Exilia pergracilis

F

 * Falsifusus
 * †Falsifusus apicalis
 * †Falsifusus bastropensis
 * †Falsifusus harrisi
 * †Falsifusus houstonensis
 * †Falsifusus ludlovicianus
 * †Falsifusus ottonis
 * †Falsifusus perobliquus
 * †Falsifusus tobar
 * Fasciolaria tulipa.png [[Fasciolaria]] – tentative report
 * †Fasciolaria plummeri
 * Felis
 * †Felis lacustris
 * †Felis rexroadensis
 * Fibularia
 * †Fibularia texana
 * †Ficopsis
 * †Ficopsis nucleoides – type locality for species
 * †Ficopsis penita
 * †Ficopsis texana
 * Ficus
 * †Ficus berryi
 * †Ficus mississippiensis
 * †Fimbriatella
 * †Fimbriatella iugum – type locality for species
 * Flabellum
 * †Flabellum concoideum
 * †Flabellum conodeum – tentative report
 * †Flabellum conoideum – type locality for species
 * †Flabellum cuneiforme
 * †Flabellum johnsonae
 * †Floridachoerus – tentative report
 * †Floridachoerus olseni
 * †Floridatragulus
 * †Floridatragulus hesperus
 * †Floridatragulus nanus
 * †Floridatragulus texanus
 * A Formica rufa collecting.jpg [[Formica]]
 * †Formica eoptera – type locality for species
 * Fossaria
 * †Fossaria dalli
 * †Fossaria obrussa
 * Fulgurofusus
 * †Fulgurofusus quercollis
 * †Fusconaia
 * †Fusconaia undulata – or unidentified comparable form
 * Fusimitra
 * †Fusimitra adamsi
 * †Fusimitra millingtoni
 * †Fusimitra perexilis
 * †Fusimitra polita
 * Fusinus monksae.jpg [[Fusinus]]
 * †Fusinus claibornica – type locality for species
 * †Fusoficula
 * †Fusoficula angelinensis
 * Fustiaria
 * †Fustiaria aciculata – type locality for species

G

 * Gadila
 * †Gadila palmerae
 * Galeocerdo
 * †Galeocerdo eaglesomei
 * †Galeocerdo latidens
 * Galeodea rugosa 001.jpg [[Galeodea]]
 * †Galeodea dubia
 * †Galeodea koureos
 * †Galeodea petersoni
 * †Galeodea planotecta
 * Gastrocopta
 * †Gastrocopta armifera
 * †Gastrocopta contracta
 * †Gastrocopta cristata
 * †Gastrocopta pellicuda
 * †Gastrocopta pellucida
 * †Gastrocopta pentodon
 * †Gastrocopta procera
 * †Gastrocopta tappaniana
 * Gavialosuchus americanus Expominer 07.jpg †[[Gavialosuchus]]
 * Gegania
 * †Gegania antiquata
 * †Gelastops
 * †Genartina – type locality for genus
 * †Genartina texana – type locality for species
 * Geochelone
 * Geomys
 * †Geomys bursarius
 * †Geomys minor
 * †Geomys tobinensis
 * †Gigantocamelus
 * †Gigantocamelus spatulus
 * †Gilbertina
 * †Gilbertina texana
 * Extm Glossotherium robustum rbh-hlmwh01913-12.jpg †[[Glossotherium]]
 * †Glossotherium chapadmalense
 * †Glottidia
 * †Glottidia antarctica – type locality for species
 * Glycymeris
 * †Glycymeris petropolitana
 * †Glyphalini
 * †Glyphalini identata
 * Glyptoactis
 * †Glyptoactis alticostata
 * †Glyptoactis coloradonis
 * †Glyptoactis crenaea
 * †Glyptoactis eoa
 * †Glyptoactis linguinodifera – type locality for species
 * †Glyptoactis milamensis – type locality for species
 * †Glyptoactis trapaquara
 * †Glyptotherium
 * †Glyptotherium cylindricum
 * †Glyptotherium texanum
 * †Glyptotoma
 * †Glyptotoma conradiana
 * †Glyptotoma crassiplicata
 * Glyptozaria
 * †Glyptozaria americanae – type locality for species
 * †Gnathabelodon – only reported species reclassified new genus Blancotherium.
 * †Gnathabelodon buckneri – type locality for species. Later reclassified as Blancotherium buckneri
 * †Gomphopages
 * †Gomphopages turneri
 * Gomphotherium productum.jpg †[[Gomphotherium]]
 * †Gomphotherium gratum – type locality for species
 * †Gomphotherium obscurum
 * †Goniobasis
 * †Goniobasis miocaenica
 * Gopherus – type locality for genus
 * †Gopherus canyonensis – type locality for species
 * †Gopherus hexagonatus
 * †Gopherus polyphemus – type locality for species
 * †Granocardium
 * Graptemys
 * †Graptemys geographica
 * Gregariella
 * †Gregariella ridgei – type locality for species
 * †Gregorymys
 * †Gregorymys riograndensis – type locality for species
 * †Gulfoceras
 * †Gulfoceras westfalli – type locality for species
 * Miacisfinal.jpg †[[Gustafsonia]]
 * †Gustafsonia cognita
 * Guttulina
 * †Guttulina problema
 * Gyraulus
 * †Gyraulus circumstriatus
 * †Gyraulus parvus

H

 * †Hadrianus
 * †Haimesiastraea
 * †Haimesiastraea conferta
 * †Haplaletes
 * †Haplaletes disceptatrix
 * †Haploconus
 * †Haploconus angustus
 * Haplocytheridea
 * †Haplocytheridea habropapillosa
 * †Haplocytheridea lisbonensis
 * †Haplocytheridea stenzeli
 * Haplohippus texanus.jpg †[[Haplohippus]]
 * †Haplohippus texanus
 * Harpa
 * †Harpactocarcinus
 * †Harpactocarcinus americanus
 * †Harpactocarcinus rathbunnae
 * †Harpagolestes
 * †Harpagolestes uintensis
 * †Harrisianella
 * †Harrisianella plicifera
 * Hastula solida 001.jpg [[Hastula]]
 * †Hastula ampulla – type locality for species
 * †Hastula houstonia
 * †Hastula longifera – type locality for species
 * †Hastula milamensis – type locality for species
 * †Hastula sabina
 * †Hastula venusta
 * Haustator
 * †Haustator infans
 * †Haustator rina
 * Hawaiia
 * †Hawaiia minuscula
 * †Hawiia
 * †Hawiia minuscula
 * Hayoceros.jpg †[[Hayoceros]]
 * †Hayoceros falkenbachi
 * Helicina
 * †Helicina orbiculata
 * Helicodiscus
 * †Helicodiscus paralellus
 * †Helicodiscus parallelus
 * †Helicodiscus singleyanus
 * †Heliconoides
 * †Heliconoides auriformis – type locality for species
 * Helisoma
 * †Helisoma anceps
 * †Helisoma trivolvis
 * Heloderma
 * †Heloderma texana – type locality for species
 * †Helohyus
 * †Helohyus lentus – or unidentified comparable form
 * Fossil maxilla Hemiauchenia Boulle.png relative Hemiauchenia]] †Hemiauchenia
 * †Hemiauchenia macrocephala
 * †Hemipsalodon
 * †Hemipsalodon viejaensis – type locality for species
 * †Hendryomeryx
 * †Hendryomeryx defordi
 * †Hendryomeryx wilsoni
 * †Heptacodon
 * †Heptacodon yeguaensis – type locality for species
 * †Hercoglossa
 * †Hercoglossa – type locality for species A informal
 * †Hercoglossa gardnerae
 * †Hercoglossa splendens
 * †Hercoglossa ulrichi
 * Herpetotherium.jpg †[[Herpetotherium]]
 * †Hesperhys – tentative report
 * †Hesperiturris
 * †Hesperiturris monilis – type locality for species
 * †Hesperiturris nodocarinatus – type locality for species
 * †Hesperoscalops
 * †Hesperoscalops blancoensis
 * †Hesperoscalops rexroadi
 * †Hesperoscalops ruficervus
 * †Hesperotestudo
 * †Hesperotestudo crassiscutata – type locality for species
 * †Hesperotestudo johnstoni – type locality for species
 * †Hesperotestudo turgida – type locality for species
 * †Hesperotestudo wilsoni
 * †Hessolestes
 * †Heteraletes
 * †Heteraletes leotanus – or unidentified comparable form
 * Heterodon
 * †Heterodon nasicus – or unidentified comparable form
 * †Heterodon platyrhinos – or unidentified comparable form
 * †Heteromeryx
 * †Heteromeryx dispar
 * Hexaplex
 * †Hexaplex colei
 * †Hexaplex eoa – type locality for species
 * †Hexaplex silvaticus
 * †Hexaplex texanus – type locality for species
 * †Hexaplex vanuxemi
 * †Hexobelomeryx – tentative report
 * Hipparion3.jpg †[[Hipparion]]
 * †Hipparion brevidontus
 * †Hipparion shirleyae
 * †Hipparion tehonense
 * †Hippidion
 * Hippodamia
 * †Hippodamia convergens – tentative report
 * Hipponix
 * †Hipponix pygmaeus
 * †Hippotherium
 * Holbrookia
 * Holmesina floridanus life reconstruction.jpg †[[Holmesina]]
 * †Holmesina septentrionalis
 * †Homotherium
 * †Homotherium johnstoni
 * †Homotherium serum
 * †Hyaenodon
 * †Hyaenodon crucians
 * †Hyaenodon horridus – or unidentified comparable form
 * †Hyaenodon montanus
 * †Hyaenodon raineyi
 * †Hyaenodon vetus – or unidentified comparable form
 * Hyla
 * †Hyla holmani – type locality for species
 * †Hyla miocenica – type locality for species
 * †Hylomeryx
 * †Hyopsodus
 * †Hyopsodus paulus
 * †Hyopsodus uintensis – or unidentified comparable form
 * †Hyopsodus wortmani – or unidentified comparable form
 * Hyotissa
 * †Hyotissa offemanae – type locality for species
 * †Hyotissa offmanna
 * †Hypertragulus
 * †Hypertragulus heikeni – or unidentified comparable form
 * Hypohippus.jpg †[[Hypohippus]]
 * †Hypohippus affinis – type locality for species
 * †Hypolagus
 * †Hypolagus edensis
 * †Hypolagus fontinalis
 * †Hypolagus furlongi
 * †Hypolagus gidleyi
 * †Hypolagus regalis
 * †Hypolagus ringoldensis
 * †Hypolagus vetus
 * †Hyrachyus
 * †Hyrachyus modestus – or unidentified comparable form
 * †Hyracodon
 * †Hyracodon medius
 * †Hyracodon petersoni
 * Hyracotherium Eohippus hharder cropped.png. Heinrich Harder (1920).]] †Hyracotherium''
 * †Hyracotherium vasacciense

I

 * †Icacorea
 * †Icacorea prepaniculata
 * Ictalurus
 * †Ictalurus punctatus
 * †Ictiobus
 * †Ignacius
 * †Ignacius frugivorus
 * Indarctos atticus.jpg †[[Indarctos]]
 * †Infracoronia
 * †Infracoronia ludoviciana
 * †Inga
 * †Inga laurinafolia
 * †Ischnognathus
 * †Ischnognathus savagei – type locality for species
 * †Ischyrocyon
 * †Ischyrocyon gidleyi – type locality for species
 * †Ischyromys
 * †Ischyromys blacki – type locality for species
 * Isognomon

J

 * †Jefitchia – type locality for genus
 * †Jefitchia copelandi – type locality for species
 * †Jepsenella
 * †Jimomys
 * †Jimomys labaughi
 * Juglans
 * †Juglans bastropensis
 * Jupiteria
 * †Jupiteria smirna

K

 * Kimberly Mural - Roger Witter Kalobatippus cropped.png †[[Kalobatippus]]
 * †Kalobatippus australis
 * †Kansasimys
 * †Kansasimys dubius
 * †Kapalmerella
 * †Kapalmerella arenicola
 * †Kapalmerella dumblei
 * †Kapalmerella mortoni
 * †Kapalmerella pleboides
 * Katherinella
 * †Katherinella smithvillensis
 * †Katherinella texitrina
 * †Katherinella trinitatis
 * Kelliella
 * †Kelliella aldrichi
 * †Kelliella evansi
 * Kellyella
 * †Kellyella texana – type locality for species
 * Kinosternon
 * †Kinosternon flavescens
 * Serpula grandis - Aalen.JPG [[Kuphus]]

L

 * †Lacinia
 * †Lacinia alveata
 * †Lacunaria
 * †Lacunaria lithae
 * †Laevibuccinum
 * †Laevibuccinum constrictum
 * †Laevibuccinum lineatum
 * †Lambdoceras
 * †Lambdoceras trinitiensis
 * †Lambertocyon
 * †Lambertocyon eximius
 * Lampropeltis getula getula.jpg, or eastern kingsnake]] Lampropeltis''
 * †Lampropeltis getulus
 * †Lampropeltis triangulum
 * †Langiopollis
 * †Langiopollis eocaenica
 * †Lapparia
 * †Lapparia crassa
 * †Lapparia dumosa
 * †Lapparia elongata
 * †Lapparia mooreana
 * †Lapparia nuda
 * †Laredochoerus – type locality for genus
 * †Laredochoerus edwardsi – type locality for species
 * †Laredomys
 * †Laredomys riograndensis – type locality for species
 * Lasionycteris
 * †Lasionycteris noctivagans
 * Lasiurus
 * †Lasiurus borealis
 * Latirus sp 001.jpg [[Latirus]]
 * †Latirus humilior
 * †Latirus moorei
 * †Latirus ostrarupis
 * †Latirus sexcostatus
 * †Latirus stephensoni
 * †Latirus traceyi – type locality for species
 * †Latrius
 * †Latrius traceyi – type locality for species
 * †Ledina
 * †Ledina smirna
 * †Ledina turgeo – type locality for species
 * †Leea
 * Lepisosteus
 * †Lepisosteus spatula – or unidentified comparable form
 * Lepomis
 * †Lepomis cyanellus – or unidentified comparable form
 * †Leptarctus
 * †Leptarctus supremus – type locality for species
 * †Leptictis
 * †Leptictis douglassi – type locality for species
 * †Leptictis wilsoni – type locality for species
 * Leptocyon gregorii holotype AMNH 12879.jpg †[[Leptocyon]]
 * †Leptocyon vafer
 * †Leptoreodon
 * †Leptoreodon edwardsi
 * †Leptoreodon leptolophus
 * †Leptoreodon major
 * †Leptoreodon marshi
 * †Leptoreodon pusillus
 * †Leptosurcula
 * †Leptosurcula beadata
 * †Leptosurcula carinata – type locality for species
 * †Leptotomus
 * Lepus
 * Jackrabbit2 crop.JPG †[[Lepus californicus]]
 * †Levifusus
 * †Levifusus dalei – tentative report
 * †Levifusus hubbardi
 * †Levifusus identus
 * †Levifusus irrasus
 * †Levifusus lithae
 * †Levifusus mortoniopsis
 * †Levifusus pagodiformis
 * †Levifusus serrae – type locality for species
 * †Levifusus supraplanus
 * †Levifusus trabeatus
 * Limacina
 * †Limacina stenzeli – type locality for species
 * †Limacina taylori
 * Flame shells cropped.jpg [[Limaria]]
 * †Limaria petropolitana
 * †Limaria smithvillensis
 * †Limnenetes
 * †Limnenetes platyceps – or unidentified comparable form
 * Limopsis
 * †Limopsis quihi
 * †Limopsis radiata
 * †Linthia
 * †Linthia alabamensis
 * †Lirodiscus
 * †Lirodiscus jacksonensis
 * †Lirodiscus smithvillensis
 * †Lirofusus
 * †Lirofusus subtenuis
 * Zelithophaga truncata.jpg [[Lithophaga]]
 * †Lithophysema
 * †Lithophysema grande
 * Litiopa
 * †Litiopa texana – type locality for species
 * †Litorhadia
 * †Litorhadia aldrichiana
 * †Litorhadia bastropensis
 * †Litorhadia compsa
 * †Litorhadia evanescentior
 * †Litorhadia milamensis – type locality for species
 * †Litorhadia petropolitana
 * †Litorhadia undulata – type locality for species
 * †Litorhadia valdefragilis – type locality for species
 * †Litoyoderimys
 * †Litoyoderimys lustrorum
 * Littorina
 * †Littorina eofasciata – type locality for species
 * †Longirostromeryx
 * †Longirostromeryx clarendonensis – type locality for species
 * †Longirostromeryx wellsi
 * Fossil Echinoid Lovenia.jpg [[Lovenia]]
 * †Lovenia alabamensis
 * Loxoconcha
 * †Loxoconcha delicata
 * Lucina
 * †Lucina subcurta
 * Lucinisca
 * Lunatia – report made of unidentified related form or using admittedly obsolete nomenclature
 * †Lunatia moorei
 * Lunularia – tentative report
 * Lunulites
 * †Lunulites bouei
 * †Lunulites ligulata
 * †Lunulites truncata
 * †Lygodiumsporites
 * †Lygodiumsporites adriennis
 * Lymnaea
 * †Lymnaea caperata
 * †Lymnaea dalli
 * †Lymnaea modicella
 * †Lymnaea obrussa
 * Lynx
 * †Lynx proterolyncis
 * Calero Creek Trail Bobcat.jpg †[[Lynx rufus]]
 * Lyria
 * †Lyrosurcula
 * †Lyrosurcula gibbera
 * †Lyrosurcula vaughani
 * Lytta

M

 * [[File:Machairodus aphanistus - Cerro de los Batallones - Museo Arqueológico Regional CAM.JPG|thumb|upright|Fossilized cranium of the Miocene-Pleistocene saber-toothed cat Machairodus]] †[[Machairodus]]
 * †Machairodus catocopis
 * Macrocallista
 * †Macrocallista triangulata – type locality for species
 * †Macrotarsius
 * †Macrotarsius jepseni – or unidentified comparable form
 * Mactra
 * Madracis
 * †Madracis gregorioi
 * †Madracis herricki – type locality for species
 * †Madracis johnsoni – type locality for species
 * Madrepora
 * †Madrepora natchitochensis
 * Magnolia
 * †Magnolia leei
 * †Mahgarita
 * †Mahgarita stevensi – type locality for species
 * †Malaquiferus – tentative report
 * †Mammut
 * †Mammut americanum
 * †Mammuthus
 * Columbian mammoth cropped.png †[[Mammuthus columbi]]
 * †Mammuthus hayi
 * Marginella
 * †Marginella carnea
 * †Marginella constrictoides
 * Marmota
 * †Marmota flaviventris
 * †Marshochoerus
 * †Marshochoerus socialis
 * Martes
 * Martesia
 * †Martesia laredoensis
 * †Martesia texana
 * †Martinogale
 * †Martinogale chisoensis
 * †Mathilda
 * †Mathilda claibornensis
 * †Mathilda cribraea – type locality for species
 * †Mathilda iugum – type locality for species
 * †Mathilda retisculpta
 * †Mauricia
 * †Mauricia houstonia
 * †Mauricia leonia
 * †Mazzalina
 * †Mazzalina conica – type locality for species
 * †Mazzalina plena
 * †Megalictis – tentative report
 * †Megalonyx
 * †Megalonyx jeffersonii – or unidentified comparable form
 * †Megalonyx leptostomus
 * Megatherium americanum cropped.png †[[Megatherium]]
 * †Megatherium mirabite
 * †Megatylopus
 * †Megatylopus matthewi – type locality for species
 * †Megatylopus primaevus
 * Melanella
 * †Melanella extremis – or unidentified related form
 * †Melanella minutissima – type locality for species
 * †Melanella notata – or unidentified comparable form
 * †Melanella wheeleri
 * †Meliakrouniomys
 * †Meliakrouniomys wilsoni – type locality for species
 * Meliosma
 * †Meliosma berryi – type locality for species
 * †Menetus
 * †Menetus dilataus
 * Menoceras NT small.jpg †[[Menoceras]]
 * †Menoceras barbouri
 * †Menops
 * †Menops bakeri
 * Mephitis
 * †Mephitis mephitis
 * Meretrix
 * †Meretrix nuttelliopsis
 * †Merychippus
 * †Merychippus gunteri
 * †Merychippus insignis – or unidentified comparable form
 * †Merychippus sejunctus
 * †Merychippus shirleyae
 * †Merychyus
 * †Merychyus calaminthus – or unidentified comparable form
 * †Merychyus novomexicanus
 * Oreodon cropped.png †[[Merycoidodon]]
 * †Merycoidodon culbertsoni
 * †Merycoidodon presidioensis
 * Mesalia
 * †Mesalia alabamiensis
 * †Mesalia allentonensis
 * †Mesalia biplicata
 * †Mesalia claibornensis
 * †Mesalia mavericki
 * †Mescalerolemur – type locality for genus
 * †Mescalerolemur horneri – type locality for species
 * Mesodesma
 * †Mesodesma singleyi
 * †Mesodma
 * †Mesodma pygmaea – or unidentified comparable form
 * †Mesodma thompsoni
 * †Mesohippus
 * †Mesohippus texanus
 * †Mesomphix
 * †Metalopex
 * †Metalopex bakeri – type locality for species
 * Knight Metamynodon.jpg †[[Metamynodon]]
 * †Metamynodon chadronensis
 * †Metamynodon mckinneyi – type locality for species
 * Metula
 * †Metula brazosensis
 * †Metula elongatoides – type locality for species
 * †Metula gracilis
 * †Metula reticulata – type locality for species
 * †Michela
 * †Michela trabeatoides – type locality for species
 * †Michenia
 * †Michenia exilis – type locality for species
 * Microdrillia fastosa 001.jpg [[Microdrillia]]
 * †Microdrillia aldrichella
 * †Microdrillia aldrichiella
 * †Microdrillia elongatula
 * †Microdrillia harrisi
 * †Microdrillia infans
 * †Microdrillia laeviplicata
 * †Microdrillia parthenoides
 * †Microdrillia robustula – or unidentified related form
 * †Microdrillia rostratula
 * †Microdrillia solidula
 * †Microeutypomys
 * †Microeutypomys karenae – type locality for species
 * †Microparamys
 * †Microparamys minutus
 * †Microparamys perfossus
 * Micropterus dolomieu2 cropped.png [[Micropterus]]
 * †Microsurcula
 * †Microsurcula iuventae – type locality for species
 * †Microsyops
 * †Microsyops annectens
 * †Microtomarctus
 * †Microtomarctus conferta
 * Microtus
 * †Microtus australis
 * †Microtus llanensis
 * †Microtus meadensis
 * †Microtus mexicanus
 * †Microtus paroperarius
 * †Microtus pennsylvanicus
 * †Microtus pinetorum
 * Micrurus
 * Coral snake.jpg †[[Micrurus fulvius]]
 * Mictomys
 * †Mictomys meltoni
 * Miltha
 * †Miltha albaripus
 * †Mimetodon
 * †Mimetodon silberlingi
 * †Minippus
 * †Minippus index
 * †Mioclaenus
 * †Mioclaenus opisthacus
 * †Miocoluber – type locality for genus
 * †Miocoluber dalquesti – type locality for species
 * †Miocyon
 * †Miocyon scotti – or unidentified comparable form
 * †Miocyon vallisrubrae
 * †Miohippus
 * †Miolabis
 * †Mionictis
 * Miracinonyx inexpectatus.jpg †[[Miracinonyx]]
 * †Miracinonyx inexpectatus – or unidentified comparable form
 * †Miracinonyx studeri
 * Mitrella
 * †Mitrella bastropensis
 * †Mitrella nuttalli – type locality for species
 * †Mitrella texana – type locality for species
 * †Mixodectes
 * †Mixodectes malaris
 * Mnestia
 * †Mnestia confusa – type locality for species
 * †Mnestia dekayi
 * †Mnestia ovata – type locality for species
 * †Mnestia rotunda – type locality for species
 * Modiolus – tentative report
 * †Monoptygma
 * †Monoptygma crassiplicum
 * Montastraea
 * †Montastraea intermedia
 * †Moropus
 * †Moropus oregonensis – or unidentified comparable form
 * †Morrillia
 * †Morrillia barbouri
 * Murex
 * †Murex fusates
 * †Murex mansfieldi
 * Mustela
 * †Mustela rexroadensis
 * Myctophum
 * †Myctophum americanum – type locality for species
 * Myliobatis
 * Mylohyus nasutus.jpg †[[Mylohyus]]
 * †Mylohyus fossilis
 * Myotis
 * †Myotis lucifugus
 * †Myotis velifer
 * Myrtea
 * †Myrtea curta
 * †Myrtea mesakta
 * †Myrtea uhleri – or unidentified comparable form
 * Mytilus
 * †Mytonomys
 * †Mytonomys coelumensis
 * †Mytonomys robustus
 * Myzinum – or unidentified comparable form

N

 * Nannippus jaw.JPG †[[Nannippus]]
 * †Nannippus aztecus
 * †Nannippus beckensis – type locality for species
 * †Nannippus lenticularis
 * †Nannippus peninsulatus
 * †Nannodectes
 * †Nannodectes gidleyi – or unidentified related form
 * †Nanotragulus
 * †Nanotragulus ordinatus
 * Narona
 * †Narona greggi
 * Nassarius
 * †Nassarius emoryi
 * †Nassarius exilis
 * †Nassarius nodosa – type locality for species
 * †Nassarius seguinensis – type locality for species
 * CoatiNosara cropped.jpg [[Nasua]]
 * †Nasua pronarica – type locality for species
 * Natica
 * †Natica aperta
 * †Natica brevisulcata – type locality for species
 * †Natica clarkeana
 * †Natica moffitti – type locality for species
 * †Natica moorei
 * †Natica permunda
 * †Natica perspecta
 * †Natica reversa
 * †Natica saffordia
 * Moon Snail cropped.jpg [[Naticarius]]
 * †Naticarius reversa
 * †Naticarius semilunata
 * Natrix
 * †Natrix erythrogaster
 * †Navajovius
 * †Navajovius kohlhaasae
 * Nectandra
 * †Nectandra lancifolia
 * †Nekrolagus
 * †Nekrolagus progressus
 * Nemocardium
 * †Nemocardium actium
 * †Nemocardium gambrinum
 * †Nemocardium quihi
 * †Nemodon
 * †Nemodon eufaulensis
 * †Neochoerus – type locality for genus
 * †Neochoerus pinckneyi
 * Neofiber
 * †Neofiber leonardi
 * Neogale
 * †Neogale vison
 * Neohipparion cropped.png †[[Neohipparion]]
 * †Neohipparion affine
 * †Neohipparion eurystyle – type locality for species
 * †Neohipparion leptode
 * †Neonatrix
 * †Neonatrix elongata
 * †Neonatrix infera – type locality for species
 * Neotamias
 * †Neotamias cinereicollis
 * Neotoma
 * †Neotoma albigula
 * †Neotoma floridana
 * †Neotoma fossilis – or unidentified comparable form
 * †Neotoma mexicana
 * Southern Plains Wood rat cropped.jpg †[[Neotoma micropus]]
 * †Neotoma minutus
 * †Neotoma quadriplicata
 * †Neozanthopsis
 * †Neozanthopsis americanus
 * Neptunea – report made of unidentified related form or using admittedly obsolete nomenclature
 * Nerodia
 * †Nerodia fasciata
 * †Nerterogeomys
 * †Nerterogeomys paenebursarius
 * Neverita
 * †Nexuotapirus
 * †Nexuotapirus marslandensis
 * Nimravides catacopis.JPG †[[Nimravides]]
 * †Nimravides hibbardi – type locality for species
 * †Nimravides thinobates – or unidentified comparable form
 * Niptus
 * †Niptus abstrusus
 * †Nonomys
 * †Nonomys simplicidens
 * Norrisia
 * †Norrisia micromphala
 * †Notharctus
 * †Notharctus tenebrosus
 * †Nothokemas
 * †Nothokemas floridanus
 * †Nothokemas hidalgensis – type locality for species
 * †Nothotylopus
 * †Nothotylopus camptognathus
 * Nothrotheriops.jpg †[[Nothrotheriops]]
 * †Nothrotheriops texanus
 * †Nothrotherium
 * †Nothrotherium shastense
 * Notiosorex
 * †Notiosorex crawfordi
 * †Notiosorex jacksoni
 * †Notiotitanops
 * †Notiotitanops mississippiensis
 * †Notolagus
 * †Notolagus lepusculus
 * Notophthalmus
 * †Notophthalmus slaughteri – type locality for species
 * Nuculidae - Nucula piacentina.jpg [[Nucula]]
 * †Nucula cochlear – type locality for species
 * †Nucula magnifica
 * †Nucula mauricensis
 * †Nucula mediavia
 * †Nucula smithvillensis
 * Nuculana
 * †Nuculana aldrichiana
 * †Nuculana corpulentoides
 * †Nuculana demissa – type locality for species
 * †Nuculana eoa
 * †Nuculana jewetti
 * †Nuculana milamensis
 * †Nuculana ovula
 * †Nuculana saffordana
 * †Nuculana smithvillensis – or unidentified related form
 * †Nuculana travisana – or unidentified comparable form
 * †Nuculana trivitate
 * †Nuculana turgeo – type locality for species
 * †Nudivagus
 * †Nuulana
 * †Nuulana turgeo – type locality for species
 * Nysius – tentative report

O

 * Oculina
 * †Oculina singleyi – type locality for species
 * Odocoileus
 * White-tailed deer.jpg †[[Odocoileus virginianus]]
 * Odontaspis
 * †Odontaspis exilis – type locality for species
 * †Odontopolys
 * †Odontopolys compsorhytis
 * Odostomia
 * †Odostomia ova – type locality for species
 * †Odostomia trapaquara
 * Ogmodontomys
 * †Ogmodontomys poaphagus
 * †Ogmophis
 * †Ogmophis miocompactus
 * Olivella
 * †Olivella mediavia
 * †Omomys
 * †Omomys carteri
 * †Omomys lloydi
 * Muskrat Foraging.JPG [[Ondatra]]
 * †Ondatra annectens
 * †Ondatra idahoensis – or unidentified comparable form
 * †Ondatra zibethicus
 * Onychomys
 * †Onychomys gidleyi
 * †Onychomys hollisteri
 * †Onychomys leucogaster
 * †Onychomys pedroensis
 * †Onychomys torridus
 * Opalia
 * †Opalia cooperi – type locality for species
 * Opheodrys
 * Opheodrys aestivus - rough green snake cropped.jpg †[[Opheodrys aestivus]]
 * Ophisaurus
 * †Oreodaphne
 * †Oreodaphne obtusifolia
 * †Oreodaphne perseaformis
 * †Oreodaphne pseudoguianensis
 * †Oromeryx
 * †Orthosurcula
 * †Orthosurcula adeona
 * †Orthosurcula francescae
 * †Orthosurcula indenta
 * †Orthosurcula langdoni – or unidentified comparable form
 * †Orthosurcula longipersa
 * †Orthosurcula persa
 * †Orthosurcula phoenicea
 * Orthoyoldia
 * †Orthoyoldia petropolitana
 * †Orthoyoldia psammotaea
 * Oryzomys
 * †Oryzomys palustris
 * Osbornoceros osborni.jpg †[[Osbornoceros]] – tentative report
 * Ostrea
 * †Ostrea crenulimarginata
 * †Ostrea duvali
 * †Ostrea frithi
 * †Ostrea kochae
 * †Ostrea multilirata
 * †Ostrea normalis
 * †Ostrea pulaskensis
 * †Ostrea semmesi
 * †Ostrea sinuosa
 * Otionella
 * †Otionella tuberosa
 * †Otostomia
 * †Otostomia melanella
 * †Otostomia trapaquara
 * †Ourayia
 * †Ourayia hopsoni
 * †Ourayia uintensis
 * Ovis
 * †Ovis canadensis
 * Oxydactylus longipes.jpg †[[Oxydactylus]]
 * †Oxydactylus benedentatus – type locality for species

P

 * †Pachecoa
 * †Pachecoa adamsi
 * †Pachecoa concentrica – type locality for species
 * †Pachecoa decisa
 * †Pachecoa microcancellata
 * †Pachecoa ovalis
 * †Pachecoa pulchra
 * †Pachecoa sabinica
 * †Pachecoa smithvillensis
 * †Paenemarmota
 * †Paenemarmota barbouri
 * †Palaechthon
 * †Palaechthon woodi – or unidentified comparable form
 * †Palaeictops – tentative report
 * †Palaeolama
 * †Palaeolama mirifica
 * Palaeophis maghrebianus life restoration cropped.jpg †[[Palaeophis]]
 * †Palaeorhaphis
 * †Palaeorhaphis palaeocenica – type locality for species
 * †Paleoheterodon
 * †Paleoheterodon tiheni
 * †Paleotomus
 * †Paleotomus senior
 * Panopea
 * Panthera
 * †Panthera leo
 * †Panthera onca
 * †Papillina
 * †Papillina dumosa
 * †Paracryptotis
 * †Paracryptotis rex
 * Paracyathus
 * †Paracyathus alternatus
 * †Paracyathus bastropensis – type locality for species
 * †Paraenhydrocyon
 * †Paraenhydrocyon wallovianus
 * †Parahippus
 * †Parahippus leonensis – type locality for species
 * †Parahyus
 * †Parahyus vagus
 * †Paralbula
 * †Paralbula marylandica
 * †Paramerychyus
 * †Paramerychyus harrisonensis
 * San Diego Paramylodon.jpg Paramylodon]] †Paramylodon
 * †Paramylodon harlani
 * †Paramys
 * †Paramys delicatior – or unidentified comparable form
 * †Paramys excavatus
 * †Paramys leptodus
 * †Paraoreomunea
 * †Parapavo
 * †Parapavo californicus
 * †Parapotos – type locality for genus
 * †Parapotos tedfordi – type locality for species
 * †Paratoceras
 * †Paratoceras macadamsi – type locality for species
 * †Paratoceras wardi – type locality for species
 * †Paratomarctus
 * †Paratomarctus euthos
 * †Paratomarctus temerarius
 * Parbatmya – type locality for genus
 * †Parbatmya brazosensis
 * †Parbatmya fornicata – type locality for species
 * †Parectypodus
 * †Parectypodus sloani
 * †Pareumys
 * †Pareumys boskeyi
 * †Paronychomys – tentative report
 * †Parvitragulus
 * †Parvitragulus priscus
 * †Parvobalanus – type locality for genus
 * †Parvobalanus gracilis – type locality for species
 * †Patulaxis
 * †Patulaxis scrobiculata
 * †Pauromys
 * †Pauromys simplex – type locality for species
 * †Pauromys texensis
 * †Pediomeryx
 * †Pediomeryx hemphillensis – type locality for species
 * Peltosaurus.JPG †[[Peltosaurus]] – tentative report
 * †Penetrigonias
 * †Penetrigonias dakotensis
 * †Peraceras
 * †Peraceras hessei
 * †Peraceras superciliosum
 * †Peradectes – tentative report
 * †Peratherium
 * †Peratherium comstocki
 * †Peratherium marsupium
 * Periploma
 * †Periploma collardi
 * †Periploma howei
 * †Periptychus
 * †Periptychus carinidens
 * Perognathus
 * †Perognathus carpenteri – type locality for species
 * Perognathus flavus.jpg †[[Perognathus flavus]]
 * †Perognathus pearlettensis
 * †Perognathus rexroadensis – or unidentified comparable form
 * Peromyscus
 * †Peromyscus boylii
 * †Peromyscus cragini
 * †Peromyscus difficilis
 * †Peromyscus eremicus
 * †Peromyscus gossypinus
 * †Peromyscus kansasensis
 * †Peromyscus leucopus
 * †Peromyscus maniculatus
 * †Peromyscus pectoralis
 * †Peromyscus progressus – or unidentified comparable form
 * †Petauristodon
 * †Petauristodon jamesi
 * †Petauristodon minimus – or unidentified comparable form
 * Petrophyllia
 * †Petrophyllia singleyi
 * †Pewelagus
 * †Pewelagus dawsonae
 * Phacoides
 * Phaedon – or unidentified comparable form
 * Phalium
 * †Phalium brevicostatum
 * †Phalium reklawensis – type locality for species
 * †Phelopteria
 * Knight Phenacodus.jpg †[[Phenacodus]]
 * †Phenacodus bisonensis
 * †Phenacodus grangeri
 * †Phenacodus matthewi
 * Philine
 * †Phlaocyon
 * †Phlaocyon annectens
 * †Phlaocyon minor
 * Pholadomya
 * †Pholadomya harrisi
 * †Pholadomya leonensis
 * †Pholadomya petropolitana
 * Pholas
 * Phos
 * †Phos sagenum
 * †Phos texanum
 * Phrynosoma
 * †Phrynosoma cornutum
 * Phyllodus
 * Physa
 * †Physa anatina
 * †Physa gyrina
 * †Physocypria
 * †Physocypria pustulosa
 * Pinna – tentative report
 * Pisidium
 * †Pisidium nitidum
 * Veneridae - Pitar lupanaria.JPG [[Pitar]]
 * †Pitar angelinae
 * †Pitar biboraensis
 * †Pitar gazleyensis
 * †Pitar hawtofi
 * †Pitar juliae
 * †Pitar kempae
 * †Pitar nuttalliopsis
 * †Pitar petropolitanus
 * †Pitar pteleina
 * †Pitar pteleinus
 * †Pitar ripleyanus
 * †Pitar texacola
 * †Pitar texibrazus
 * †Pitar tornadonis
 * †Pitar trigoniata
 * †Pitar turneri – type locality for species
 * Pituophis
 * †Pituophis melanoleucus
 * †Plagiarca
 * †Plagiarca rhomboidella
 * †Plagiarca vaughani
 * Plagiocardium – or unidentified comparable form
 * Planorbis
 * †Planorbis andersoni
 * †Planorbula
 * †Planorbula armigera
 * Platygonus leptorhinus cropped.png of the genus Platygonus. Charles R. Knight (1922).]] †Platygonus
 * †Platygonus bicalcaratus
 * †Platygonus compressus
 * †Platygonus pollenae
 * †Platygonus vetus
 * Platytrochus
 * †Platytrochus primaevus – type locality for species
 * †Platytrochus stokesi
 * †Pleiolama
 * †Pleiolama vera
 * †Plesiocolopirus
 * †Plesiocolopirus hancocki – or unidentified comparable form
 * †Plesiogulo
 * †Plesiogulo marshalli
 * †Plesiolestes
 * †Plesiolestes nacimienti
 * †Plesiosminthus
 * †Pleuofusia – tentative report
 * †Pleuofusia huppertzi – type locality for species
 * Pleurocera
 * †Pleurocera acutum
 * Pleurofusia
 * †Pleurofusia huppertzi
 * †Pleurofusia longirostropis
 * †Pleurofusia prosseri
 * †Pleurolicus
 * †Pleurolicus sellardsi
 * †Pleuroliria
 * Pleuromeris
 * †Pleuromeris leonensis
 * Pleuroploca trapezium 01.JPG [[Pleuroploca]]
 * †Pleuroploca plummeri – or unidentified related form
 * †Pleurostoma
 * †Pleurostoma adolescens
 * Pleurotomella
 * †Pleurotomella veatchi
 * †Pleurotomella whitfieldi
 * Plicatula
 * †Plicatula filamentosa
 * †Plicatula pustula – type locality for species
 * Pliciscala
 * †Pliciscala albitesta
 * †Plinthicus
 * Pliohippus Pernix.jpg †[[Pliohippus]]
 * †Pliohippus fossulatus
 * †Pliohippus nobilis
 * †Pliohippus pernix
 * †Pliohippus spectans – tentative report
 * †Pliometanastes
 * †Pliometanastes protistus – or unidentified comparable form
 * †Pliosaccomys
 * †Pliosaccomys higginsensis
 * †Pliotaxidea
 * †Pliotaxidea nevadensis – or unidentified comparable form
 * †Plotophysops – tentative report
 * †Plotophysops angularis – type locality for species
 * †Poabromylus
 * †Poabromylus kayi
 * Podomys
 * †Podomys oklahomensis
 * Poebrotherium.jpg †[[Poebrotherium]]
 * †Poebrotherium chadronense – type locality for species
 * †Poebrotherium franki – type locality for species
 * †Polidevcia
 * †Polidevcia magna
 * Polinices
 * †Polinices aratus
 * †Polinices eminulus
 * †Polinices harrisii
 * †Polinices julianna
 * †Polinices onustus – type locality for species
 * Polydora
 * Polygyra
 * †Polygyra texasiana
 * Polymorphina
 * †Polymorphina gibba
 * †Polymorphina regularis
 * Polyschides
 * †Polyschides margarita
 * Caribbean Porites.JPG [[Porites]]
 * †Porites douvillei
 * Poromya – or unidentified related form
 * †Postalia
 * †Postalia americana – type locality for species
 * †Potamides
 * †Potamides matsoni
 * †Pratilepus
 * †Pratilepus kansasensis
 * †Preophidion – type locality for genus
 * †Preophidion petropolis
 * †Preophidion stintoni – type locality for species
 * Prionocidaris
 * †Prionocidaris cojimarensis
 * †Priscocamelus
 * †Priscocamelus wilsoni
 * †Priscoficus
 * †Priscoficus juvenis
 * †Pristichampsus
 * Pristis
 * †Probassariscus
 * †Problastomeryx
 * †Problastomeryx primus
 * †Procamelus
 * †Procamelus grandis
 * †Procamelus leptognathus
 * †Procamelus occidentalis
 * †Procastoroides
 * †Procastoroides sweeti
 * †Procynodictis
 * †Procynodictis vulpiceps – or unidentified comparable form
 * Procyon
 * †Procyon lotor
 * †Procyon rexroadensis
 * †Prodipodomys
 * †Prodipodomys centralis
 * †Progeomys
 * †Progeomys sulcatus – type locality for species
 * †Prohesperocyon
 * †Prohesperocyon wilsoni
 * †Proheteromys
 * †Proheteromys sabinensis – type locality for species
 * †Proheteromys toledoensis – type locality for species
 * †Prolapsus
 * †Prolapsus junctionis – type locality for species
 * †Prolapsus sibilatoris – type locality for species
 * †Promathildia
 * †Promathildia parvilis – or unidentified comparable form
 * †Promathildia parvula – or unidentified comparable form
 * Promenetus
 * †Promenetus exacuous
 * †Promioclaenus
 * †Promioclaenus acolytus
 * †Proneofiber
 * †Proneofiber guildayi – type locality for species
 * Propeamussiidae - Propeamussium eocenicum.JPG [[Propeamussium]]
 * †Propeamussium alabamense
 * †Prosigmodon
 * †Prosimnia
 * †Prosimnia naviculae
 * †Prosthennops
 * †Prosthennops serus
 * †Prosthennops xiphodonticus
 * †Prosynthetoceras
 * †Prosynthetoceras francisi – type locality for species
 * †Prosynthetoceras orthrionanus – type locality for species
 * †Prosynthetoceras texanus – type locality for species
 * †Proterixoides
 * †Prothryptacodon
 * †Protictis
 * Titanothere Osborn Protitanotherium.jpg †[[Protitanotherium]]
 * †Protitanotherium emarginatum
 * †Protoceras – tentative report
 * †Protocitta
 * †Protocitta ajax – type locality for species
 * †Protohippus
 * †Protohippus gidleyi
 * †Protohippus perditus
 * †Protohippus supremus – type locality for species
 * †Protohippus vetus
 * †Protolabis
 * †Protolabis coartatus
 * †Protoreodon
 * †Protoreodon parvus
 * †Protoreodon petersoni
 * †Protoreodon pumilus
 * †Protosciurus
 * †Protoscutella
 * †Protoscutella mississippiensis
 * †Protoselene – or unidentified comparable form
 * †Protospermophilus
 * †Protospermophilus quatalensis
 * †Protosurcula
 * †Protosurcula aurora – type locality for species
 * †Protosurcula gabbii
 * †Protosurcula tenuirostris
 * †Protylopus – tentative report
 * Pseudacris
 * †Pseudacris clarki
 * †Pseudacris ocularis
 * †Pseudacris streckeri
 * †Pseudaelurus – tentative report
 * Pseudohipparion retrusus.JPG †[[Pseudhipparion]]
 * †Pseudhipparion curtivallum
 * †Pseudhipparion hessei – type locality for species
 * †Pseudhipparion skinneri
 * †Pseudoceras
 * †Pseudoceras skinneri
 * Pseudochama
 * †Pseudocylindrodon
 * †Pseudocylindrodon neglectus
 * †Pseudocylindrodon pintoensis – or unidentified related form
 * †Pseudocylindrodon texanus – type locality for species
 * Pseudoliva
 * †Pseudoliva ostrarupis
 * †Pseudoliva santander
 * †Pseudoliva scalina
 * †Pseudoliva vetusta
 * Pseudomalaxis
 * †Pseudomalaxis acuta – type locality for species
 * †Pseudomalaxis plummerae
 * †Pseudomalaxis reklawensis – type locality for species
 * †Pseudomalaxis texana
 * †Pseudometula – type locality for genus
 * †Pseudometula gradus – type locality for species
 * †Pseudoparablastomeryx
 * †Pseudoparablastomeryx scotti
 * Pseudoprotoceras fossil.jpg †[[Pseudoprotoceras]]
 * †Pseudoprotoceras minor
 * †Pseudotheridomys
 * †Pseudotomus
 * †Pseudotomus johanniculi
 * †Pseudotomus petersoni – or unidentified comparable form
 * †Psittacotherium
 * †Psittacotherium multifragum
 * Pteria
 * †Pteria deusseni
 * †Pteria limula
 * †Pteria petropolitana
 * Pteris
 * †Pteris dentata
 * †Pteropsella
 * †Pteropsella lapidosa
 * †Pteropsella praelapidosa
 * †Pterosphenus
 * †Pterosphenus schucherti
 * Pterothrissus
 * †Pterothrissus truncatus
 * Pterynotus
 * †Pterynotus sabinola
 * †Pterynotus stenzeli – type locality for species
 * Ptilodus skull BW cropped.jpg †[[Ptilodus]]
 * †Ptilodus mediaevus
 * Ptinus
 * Puma
 * †Puma concolor
 * Pupilla
 * †Pupilla blandi
 * Pupoides
 * †Pupoides albilabris
 * Pycnodonte
 * †Pycnodonte sylvaerupis
 * †Pylodictis
 * Pylodictis olivaris cropped.jpg †[[Pylodictis olivaris]]
 * Pyramidella
 * †Pyramidella bastropensis
 * †Pyramidella dalli
 * †Pyramidella filamentosa – type locality for species
 * †Pyramidella perexilis
 * †Pyramidella pirum – type locality for species
 * †Pyramidella propeacicula
 * †Pyramidella pseudopymaea
 * †Pyramidella tundrae – type locality for species
 * †Pyramimitra
 * †Pyramimitra eocenica – type locality for species
 * †Pyramimitra terebraeformis
 * †Pyricythereis
 * †Pyricythereis alabamensis
 * †Pyricythereis delicata – type locality for species
 * †Pyricythereis foveovalva – type locality for species
 * †Pyricythereis seminuda – type locality for species
 * †Pyricythereis smithvillensis – type locality for species
 * †Pyricythereis subtriangularis – type locality for species

Q

 * †Quadratomus
 * †Quadratomus gigans
 * Winged mapleleaf.jpg †[[Quadrula]]
 * †Quadrula frustulosa
 * †Quadrula speciosa
 * Quinqueloculina
 * †Quinqueloculina claiborniana
 * †Quinqueloculina seminulum
 * †Quinqueloculina vulgaris

R

 * Raja
 * Fish4419 - Flickr - NOAA Photo Library.jpg †[[Raja texana]] – type locality for species
 * †Rana
 * †Rana catesbiana – lapsus calami of Rana catesbeiana
 * †Rana pipiens
 * Ranularia
 * †Ranularia hula
 * Raphitoma
 * †Raphitoma bastropensis – type locality for species
 * †Raphitoma bellula
 * †Raphitoma fannae
 * †Raphitoma georgei – type locality for species
 * †Raphitoma iuventae – type locality for species
 * †Raphitoma rebecella
 * †Raphitoma sabinia
 * †Raphitoma specus
 * Reithrodontomys
 * †Reithrodontomys fulvescens
 * †Reithrodontomys megalotis
 * †Reithrodontomys montanus
 * †Reithrodontomys moorei
 * †Reithrodontomys rexroadensis – or unidentified comparable form
 * †Retinella
 * †Retinella indentata
 * Retusa.png [[Retusa]]
 * †Retusa adamsi
 * †Retusa adamski – or unidentified comparable form
 * †Retusa emoryi
 * †Retusa galba
 * †Retusa jacksonensis
 * †Retusa kellogii
 * †Retusa notata – type locality for species
 * †Retusa sylvaerupis
 * †Rhabdopitaria
 * †Rhabdopitaria astartoides
 * †Rhabdopitaria pricei
 * †Rhabdopitaria texangelina
 * Rhinobatos
 * Rhinocheilus
 * †Rhinocheilus lecontei
 * Rhinoptera
 * Rhizorus
 * †Rhizorus conradianus
 * †Rhizorus loisae
 * †Rhizorus minutissimus
 * †Rhizorus smithvillensis
 * †Rhizorus volutatus
 * Rhynchotherium falconeri.png †[[Rhynchotherium]] – tentative report
 * Rimella
 * †Rimella laqueatus
 * †Rimella texanum
 * Ringicula
 * †Ringicula alabamensis
 * †Ringicula butleriana – tentative report
 * †Ringicula dubia
 * †Ringicula trapaquara
 * †Rooneyia – type locality for genus
 * †Rooneyia viejaensis – type locality for species
 * †Rotalia
 * †Rotalia beccarii
 * †Rotularia
 * †Rudiscala

S

 * Saccella
 * †Saccella atakta
 * Salvadora
 * †Salvadora paleolineata
 * †Sapindus
 * †Sapindus linearifolius
 * Sassia semitorta.jpg [[Sassia]]
 * †Sassia nucleoides – type locality for species
 * †Sassia septemdentata
 * †Sassia septendentata
 * †Saxolucina
 * †Saxolucina claytonia
 * Scalina
 * †Scalina dolosa
 * †Scalina trapaquara
 * Scalopus
 * †Scalopus aquaticus
 * Scaphander
 * Scaphella
 * †Scaphella newcombiana
 * †Scaphella showalteri
 * Scaphiopus couchii ANRA.jpg [[Scaphiopus]]
 * †Scaphites
 * Sceloporus
 * †Sceloporus olivaceus
 * †Sceloporus undulatus
 * †Scenopagus
 * †Scenopagus edenensis – or unidentified comparable form
 * †Schedocardia
 * †Schedocardia hatchetigbeensis
 * †Schizorthosecos
 * †Schizorthosecos interstitia
 * Sciurus
 * Eastern Grey Squirrel.jpg †[[Sciurus carolinensis]]
 * †Sciurus niger
 * Scobinella
 * †Scobinella reticulatoides
 * †Selaginella
 * Selenophorus – or unidentified comparable form
 * Semele
 * †Semele australina
 * †Semiactaeon
 * †Semiactaeon texanum – type locality for species
 * †Septastrea
 * †Septastrea kerioides – type locality for species
 * Serpulorbis
 * †Serpulorbis gonioides
 * †Serpulorbis multiclavus – type locality for species
 * Sigatica
 * †Sigatica harrisi
 * Sigmodon
 * †Sigmodon curtisi – or unidentified comparable form
 * Sigmodon hispidus1.jpg †[[Sigmodon hispidus]]
 * †Sigmodon hudspethensis – type locality for species
 * †Sigmodon minor
 * †Signata – type locality for genus
 * †Signata nicoli – type locality for species
 * †Signata stenzeli – type locality for species
 * Siliqua
 * †Siliqua simondsi
 * †Simidectes
 * †Simidectes magnus
 * †Similisciurus
 * †Similisciurus maxwelli – type locality for species
 * †Simimys – or unidentified comparable form
 * Simnia
 * †Simnia texana
 * Sincola
 * †Sincola galvestonensis
 * Sinodia
 * †Sinodia eocaenica
 * Sinopa rapax 1.jpg †[[Sinopa]]
 * †Sinopa major
 * Sinum
 * †Sinum arctatum
 * †Sinum bilix
 * †Sinum declive
 * †Sinum fiski – type locality for species
 * †Sinum inconstans
 * †Sinum moveum – type locality for species
 * †Sinum taylori – type locality for species
 * Siphonalia
 * †Siphonalia newtonensis
 * †Siphonalia plummeri
 * Siren
 * †Siren miotexana – type locality for species
 * †Skaptotion
 * †Skaptotion reklawensis – type locality for species
 * Skena
 * †Skena pignus
 * Skenea
 * †Skenea dalli
 * Smilodon fatalis.jpg †[[Smilodon]]
 * †Smilodon fatalis
 * †Soergelia
 * †Soergelia mayfieldi
 * Solariella
 * †Solariella aldrichiana
 * †Solariella tricostata
 * Solariorbis
 * †Solariorbis conicus – type locality for species
 * †Solariorbis discoides – type locality for species
 * †Solariorbis parsnaticoide – type locality for species
 * †Solariorbis parsnaticoides – type locality for species
 * †Solariorbis proius
 * †Solariorbis velarum – type locality for species
 * †Solastella – type locality for genus
 * †Solastella cookei – type locality for species
 * Solemya
 * †Solemya bilix
 * Solen
 * †Solen pendletonensis
 * Solena
 * †Solena shirleyi – type locality for species
 * †Sophora
 * †Sophora wilcoxiana
 * Sorex
 * †Sorex cinereus
 * †Sorex cudahyensis
 * †Sorex lacustris
 * †Sorex megapalustris
 * Northern water shrew with young.jpg †[[Sorex palustris]]
 * †Sorex pratensis
 * †Sorex taylori
 * †Sorex vagrans
 * Spermophilus
 * †Spermophilus elegans – or unidentified comparable form
 * †Spermophilus finlayensis
 * †Spermophilus howelli – or unidentified comparable form
 * †Spermophilus mcgheei
 * †Spermophilus spilosoma
 * Groundsquirrel4-300 cropped.jpg (formerly Spermophilus tridecemlineatus), or thirteen-lined ground squirrel]] †Spermophilus tridecemlineatus''
 * †Spermophilus variegatus
 * Sphaerium
 * †Sphaerium striatinum
 * †Sphyreana
 * Spilogale
 * †Spilogale microdens
 * †Spilogale putorius
 * †Spilogale rexroadi
 * †Spinizoncolpites
 * †Spinizoncolpites prominatus
 * Spirorbis
 * †Spirorbis leptostoma
 * Spirotropis
 * †Spirotropis claibornica – type locality for species
 * Spisula
 * †Spisula parilis
 * Sportella – tentative report
 * †Sportella divaricata
 * Stagnicola
 * †Stagnicola bulimoides
 * †Stagnicola exilis
 * †Stagnicola reflexa
 * Stegomastodon mirificus - Smithsonian.JPG †[[Stegomastodon]]
 * †Stegomastodon mirificus
 * †Steneofiber
 * †Steneofiber barbouri – or unidentified comparable form
 * †Steneofiber fossor
 * †Steneofiber hesperus
 * †Stenomylus
 * †Stenotrema
 * †Stenotrema leai
 * †Stenotrema monodon
 * Sternotherus
 * Sthenictis
 * †Stintonia
 * †Stintonia brazosia
 * Fossil ruminant.jpg †[[Stockoceros]] – or unidentified comparable form
 * Storeria
 * †Storeria dekayi
 * †Strepsidura
 * †Strepsidura contorea
 * †Strepsidura ficus
 * †Strepsidura harrisi – type locality for species
 * Striarca
 * †Striarca stearnsii
 * †Striarca webbervillensis
 * †Striatolamia
 * †Striatolamia macrota
 * Strobilops
 * †Strobilops texasiana
 * †Stygimys
 * †Stygimys vastus – type locality for species
 * Stylinodon mirusDB24.jpg]] †Stylinodon''
 * Succinea
 * †Succinea avara
 * †Sulcocypraea
 * †Sulcocypraea kennedyi
 * Surculites
 * †Surculites cabezai
 * †Surculites lapillus – type locality for species
 * †Surculoma
 * †Surculoma dumblei
 * †Surculoma falsabenes
 * †Surculoma imbricata – type locality for species
 * †Surculoma kellogii
 * †Surculoma leoncola
 * †Surculoma penrosei
 * †Sycostoma
 * †Sycostoma texana – type locality for species
 * Sylvilagus
 * †Sylvilagus audubonii
 * †Sylvilagus floridanus
 * †Sylvilagus hibbardi
 * †Symmetrodontomys
 * †Symmetrodontomys beckensis
 * †Symmetrodontomys simplicidens
 * †Symplocos
 * †Symplocos amoena – type locality for species
 * †Symplocos fritschii – type locality for species
 * †Symplocos martinettoi – type locality for species
 * †Symplocos platycarpa – type locality for species
 * †Symplocos rothwelii – type locality for species
 * †Symplocos trinitiensis – type locality for species
 * †Symplocos trisulcata – type locality for species
 * Synaptomys
 * †Synaptomys australis – or unidentified comparable form
 * †Synaptomys cooperi
 * †Syncyclonema
 * Synthetoceras BW.jpg †[[Synthetoceras]]
 * †Synthetoceras tricornatus – type locality for species
 * Syrphus – or unidentified comparable form
 * Syrrhophus
 * †Syrrhophus marnocki

T

 * Tantilla
 * Tanytarsus – tentative report
 * South American tapir (Tapirus terrestris).JPG [[Tapirus]]
 * †Tapirus haysii
 * †Tapirus veroensis
 * Taxidea
 * †Taxidea taxus
 * Teinostoma
 * †Teinostoma barryi – type locality for species
 * †Teinostoma eoa
 * †Teinostoma texanum
 * Teleoceras Horsfall cropped.jpg †[[Teleoceras]]
 * †Teleoceras fossiger
 * †Teleoceras guymonense
 * †Teleoceras hicksi
 * †Teleoceras major
 * †Teleoceras medicornutum
 * †Teleoceras meridianum
 * Tellina fabula.jpg [[Tellina]]
 * †Tellina cherokeensis
 * †Tellina leana
 * †Tellina makelloides
 * †Tellina petropolitana
 * †Tellina quihi
 * †Tellina santander
 * †Tellina semipapyra – or unidentified comparable form
 * †Tellina semipapyria
 * †Tellina tallicheti
 * †Tellina trumani
 * Tenagodus anguinus 01.JPG [[Tenagodus]]
 * †Tenagodus texanus
 * †Tenuimactra – type locality for genus
 * †Tenuimactra hodgkinsoni – type locality for species
 * †Tephrocyon
 * †Tephrocyon scitulus
 * Terebellum
 * Terebra
 * †Terebra texagyra
 * †Terebrifusus
 * †Terebrifusus amoenus
 * †Terebrifusus multiplicatus
 * Teredo
 * †Teredo maverickensis
 * †Teredo ringens
 * Terminalia
 * †Terminalia hilgardiana
 * †Ternstroemites
 * †Ternstroemites preclaibornensis
 * Terrapene
 * †Terrapene carolina
 * †Terrapene ornata
 * Testudo
 * Tetrameryx shuleri.png †[[Tetrameryx]]
 * †Tetrameryx knoxensis
 * †Tetrameryx shuleri
 * †Texasophis – type locality for genus
 * †Texasophis fossilis – type locality for species
 * †Texmelanatria
 * †Texmelanatria angeloi
 * †Texmelanatria texana
 * †Texoceros
 * †Texoceros altidens – type locality for species
 * †Texodon
 * †Texodon meridianus – type locality for species
 * †Texomys
 * †Texomys ritchiei – type locality for species
 * Thamnophis
 * †Thamnophis proximus
 * †Thamnophis saurita
 * †Thamnophis sirtalis
 * Theodoxus
 * †Theodoxus domicilium – type locality for species
 * Thinobadistes cropped.jpg †[[Thinobadistes]]
 * †Thinobadistes wetzeli
 * †Thisbemys
 * †Thisbemys corrugatus
 * Thomomys
 * †Thomomys bottae
 * †Thomomys talpoides – or unidentified comparable form
 * †Tibiella – report made of unidentified related form or using admittedly obsolete nomenclature
 * †Tibiella texana
 * †Tiburnus
 * †Tiburnus texanus
 * †Ticholeptus
 * †Ticholeptus rileyi – type locality for species
 * Titanoides2010.jpg †[[Titanoides]]
 * †Titanoides gidleyi – or unidentified comparable form
 * †Tomarctus
 * †Tomarctus brevirostris
 * †Tornatellaea
 * †Tornatellaea leai
 * †Tornatellaea quercollis – tentative report
 * †Tornatellaea texana
 * †Tornatina – report made of unidentified related form or using admittedly obsolete nomenclature
 * †Tornatina angelinae
 * †Toromeryx
 * †Toromeryx marginensis – type locality for species
 * †Toxotherium
 * †Toxotherium hunteri
 * †Transovula
 * †Transovula scobina – type locality for species
 * †Trichiuris
 * †Trigonias – tentative report
 * †Trigonictis
 * †Trigonictis cookii
 * Trigonostoma
 * †Trigonostoma babylonicum
 * †Trigonostoma elegantissima – type locality for species
 * †Trigonostoma gemmatum
 * †Trigonostoma harrisi
 * †Trigonostoma herbae – type locality for species
 * †Trigonostoma jonesae – type locality for species
 * †Trigonostoma panones
 * †Trigonostoma penrosei
 * †Trigonostoma sabinetownense
 * †Trigonostoma sabinetownensis – type locality for species
 * Trigonulina
 * †Trigonulina satex
 * †Trimalaxis – type locality for genus
 * †Trimalaxis ora – type locality for species
 * †Trinacria
 * †Trinacria microcancellata – type locality for species
 * †Tripia
 * †Tripia anteatripla – tentative report
 * †Triplopus – tentative report
 * †Triplopus implicatus – or unidentified comparable form
 * Trochita
 * †Trochita aperta
 * Trochocyathus
 * †Trochocyathus coloradoensis – type locality for species
 * †Trochocyathus uber – type locality for species
 * Tropidoclonion lineatum texanum.jpg [[Tropidoclonion]]
 * †Tropidoclonion lineatum
 * †Tropisurcula
 * †Tropisurcula crenula – tentative report
 * †Tropisurcula grandis – type locality for species
 * †Tropisurcula milamensis – type locality for species
 * †Tropisurcula planus – type locality for species
 * †Truncilla
 * †Truncilla truncata
 * †Trygon
 * †Trygon alveolatus – type locality for species
 * †Trypanotoma
 * †Trypanotoma longispira
 * †Trypanotoma terebriformis
 * †Trypanotopsis
 * †Trypanotopsis texana
 * †Tuba
 * †Tuba antiquata
 * Tubiola
 * †Tubiola gracilis – type locality for species
 * Glycymerididae - Tucetona laticostata.jpg [[Tucetona]]
 * †Tucetona sabinensis
 * †Turbinolia
 * †Turbinolia pharetra
 * †Turbinolia subtercisa – type locality for species
 * †Turbinolia tenuis
 * Turboella
 * Turbonilla
 * †Turbonilla clinensis
 * †Turbonilla meta – type locality for species
 * †Turbonilla neglecta – type locality for species
 * Turpinia
 * †Turpinia tiffneyi – type locality for species
 * Turricula
 * †Turricula floweri
 * †Turricula nasuta
 * †Turricula plenta
 * Turris babylonia shell.jpg [[Turris]]
 * †Turris bimaniofus – or unidentified comparable form
 * †Turris capax
 * †Turris mediavia
 * †Turris nadoideus
 * †Turris nasuta – or unidentified comparable form
 * †Turris rockscreekensis
 * †Turris specus
 * Turritella
 * †Turritella – type locality for species informal
 * †Turritella bellifera
 * †Turritella biplicata – or unidentified comparable form
 * †Turritella chirena
 * †Turritella cortezi
 * †Turritella dutexata
 * †Turritella eurynome
 * †Turritella femina
 * †Turritella hilli
 * †Turritella houstonia
 * †Turritella humerosa
 * †Turritella kincaidensis
 * †Turritella nasuta
 * †Turritella nerinexa
 * †Turritella ola
 * †Turritella plummeri
 * †Turritella polysticha
 * †Turritella prehumerosa
 * †Turritella premortoni
 * †Turritella turneri
 * †Tylotrochus
 * LesserPrairieChicken.JPG [[Tympanuchus]]
 * Typhina
 * †Typhina palmerae
 * †Typodus
 * †Typodus thyroidea
 * Tyto
 * †Tyto alba

U

 * Uintatherium DB.jpg †[[Uintatherium]] – or unidentified comparable form
 * †Uintatherium anceps
 * Umbraculum
 * †Umbraculum planulatum
 * †Umbraculum tomaculum – type locality for species
 * Unio
 * Urocyon
 * †Urocyon cinereoargenteus – or unidentified comparable form
 * †Urocyon galushai
 * Uromitra
 * †Uromitra brazosana
 * Ursus
 * †Ursus americanus
 * †Ustatochoerus
 * †Ustatochoerus leptoscelos
 * †Ustatochoerus major

V

 * Vallonia pulchella.jpg [[Vallonia]]
 * †Vallonia gracilicosta
 * †Vallonia parvula
 * †Varicobela
 * †Varicobela filum – type locality for species
 * Venericardia
 * †Venericardia bashiplata
 * †Venericardia densata – type locality for species
 * †Venericardia dua
 * †Venericardia eoa
 * †Venericardia horatiana
 * †Venericardia jewelli
 * †Venericardia mediaplata
 * †Venericardia planicosta
 * †Venericardia rotunda
 * †Venericardia smithi
 * †Venericardia smithii
 * †Venericardia stewarti
 * †Venericardia texalana
 * Verticordia
 * †Verticordia satex – or unidentified comparable form
 * Vertigo
 * Vertigo ovata aperture.jpg †[[Vertigo ovata]]
 * †Vetericardiella
 * †Vetericardiella webbervillensis
 * Vibracellina
 * †Vibracellina capillaria
 * †Viejadjidaumo
 * †Viejadjidaumo magniscopuli – type locality for species
 * †Viridomys
 * †Vokesula
 * †Vokesula aldrichi
 * †Vokesula smithvillensis
 * †Volutostrombus – type locality for genus
 * †Volutostrombus eocenica – type locality for species
 * †Volvaria
 * †Volvaria gabbiana
 * †Volvaria reticulata
 * †Volvariella
 * †Volvariella milamensis – type locality for species
 * Volvulella
 * †Volvulella reklawensis – type locality for species
 * Vulpes
 * †Vulpes stenognathus
 * Swift Fox Colorado Wolf and Wildlife cropped.jpg †[[Vulpes velox]]
 * †Vulpes vulpes

X

 * †Xenochelys
 * Canis cf falconeri.JPG †[[Xenocyon]]
 * †Xenocyon texanus
 * Xenophora

Y

 * Yoldia
 * †Yoldia houstonia
 * †Yoldia kindlei
 * †Yoldia praecompsa
 * Yua
 * †Yua texana – type locality for species
 * †Yumaceras
 * †Yumaceras figginsi – or unidentified comparable form

Z

 * †Zanthopsis
 * †Zanthopsis peytoni
 * †Zanycteris – tentative report
 * Zonitoides
 * Zonitoides arboreus.jpg †[[Zonitoides arboreus]]