List of the Cenozoic life of Wyoming

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

• †Aaptoryctes
  • †Aaptoryctes ivyi
• †Absarokius
  • †Absarokius abbotti
  • †Absarokius gazini – type locality for species
  • †Absarokius metoecus – type locality for species
• †Abuta – or unidentified related form
• †Acacia
  • †Acacia lamarensis
  • †Acacia macrosperma
  • †Acacia wardii
• †Acarictis
  • †Acarictis ryani – type locality for species
• Accipiter

  • 

    Accipiter gentilis
  • †Accipiter striatus
• Acer
  • †Acer lesquereuxi
  • †Acer newberryi
  • †Acer silberlingii
  • †Acer vivarium
• †Aceroryctes – type locality for genus
  • †Aceroryctes dulcis – type locality for species
• †Achaenodon
  • †Achaenodon insolens – type locality for species
  • †Achaenodon robustus – type locality for species
• †Acidomomys – type locality for genus
  • †Acidomomys hebeticus – type locality for species
• †Acmeodon
  • †Acmeodon secans
• †Acocephalus
  • †Acocephalus adae – type locality for species
• †Acritoparamys
  • †Acritoparamys atavus
  • †Acritoparamys atwateri
  • †Acritoparamys francesi
  • †Acritoparamys wyomingensis

• 

  Acrostichum
  • †Acrostichum hesperium
• †Adilophontes – type locality for genus
  • †Adilophontes brachykolos – type locality for species
• †Adjidaumo
  • †Adjidaumo burkei – tentative report
  • †Adjidaumo craigi – or unidentified comparable form
  • †Adjidaumo minimus

• 

  †Adocus
• †Adunator
  • †Adunator fredericki
  • †Adunator ladae
  • †Adunator martinezi
• Aegialia
  • †Aegialia rupta – type locality for species
• Aegolius
  • †Aegolius acadicus
  • Aegolius funereus

• 

  †Aepycamelus
• †Aerugoamnis – type locality for genus
  • †Aerugoamnis paulus – type locality for species
• †Aesculus
  • †Aesculus antiquorum
  • †Aesculus hickeyi
• †Afairiguana – type locality for genus
  • †Afairiguana avius – type locality for species
• †Ageina
  • †Ageina tobieni
• †Ageitodendron
  • †Ageitodendron matthewi
• Agelaius
  • †Agelaius phoeniceus
• †Agnotocastor
  • †Agnotocastor galushai – type locality for species

• 

  †Agriochoerus
  • †Agriochoerus maximus
  • †Agriochoerus minimus – or unidentified comparable form
• Ailanthus
  • †Ailanthus lesquereuxi
• †Alagomys
  • †Alagomys russelli – type locality for species
• †Alastor
  • †Alastor solidescens – type locality for species
• †Albertanella – or unidentified comparable form
  • †Albertanella minuta
• Alces
  • †Alces alces
• †Aletodon
  • †Aletodon conardae – type locality for species
  • †Aletodon gunnelli – type locality for species
  • †Aletodon quadravus

• 

  †Aletomeryx
  • †Aletomeryx gracilis
• †Aletornis – type locality for genus
  • †Aletornis bellus – type locality for species
  • †Aletornis gracilis – type locality for species
  • †Aletornis nobilis – type locality for species
  • †Aletornis pernix – type locality for species
  • †Aletornis venustus – type locality for species
• Aleurites
  • †Aleurites glandulosa
• †Alismaphyllites
  • †Alismaphyllites grandifolius
• †Allantodiopsis
  • †Allantoidiopsis erosa

• 

  †Allognathosuchus
  • †Allognathosuchus heterodon
  • †Allognathosuchus polyodon
  • †Allognathosuchus wartheni – type locality for species
• †Allomys
  • †Allomys cristabrevis
• †Allophylus
  • †Allophylus flexifolia
• Alnus^{[citation needed]}
• †Alphagaulus
  • †Alphagaulus vetus
• †Alticonus
  • †Alticonus gazini
• †Alveojunctus
  • †Alveojunctus minutus
• †Alveugena
  • †Alveugena carbonensis – type locality for species
• †Amaramnis
  • †Amaramnis gregoryi – type locality for species
• †Ambloctonus
  • †Ambloctonus major
  • †Ambloctonus priscus – or unidentified comparable form
  • †Ambloctonus sinosus
• †Ameiseophis
  • †Ameiseophis robinsoni – type locality for species
• †Amelotabes – type locality for genus
  • †Amelotabes simpsoni – type locality for species

• 

  Amentotaxus
  • †Amentotaxus campbelli
• Amia
  • †Amia fragosa
• †Amitabha – type locality for genus
  • †Amitabha urbsinterdictensis – type locality for species
• †Ampelopsis
  • †Ampelopsis acerifolia
• †Amphechinus
  • †Amphechinus ellicottae – type locality for species
• †Amphigyion
  • †Amphigyion straitae
• †Amphilemur
• †Amphiplaga
• Amphiuma
  • †Amphiuma jepseni – type locality for species
• †Ampliconus
  • †Ampliconus antoni – type locality for species

• 

  Amyda
  • †Amyda egregia – type locality for species
  • †Amyda exquisita – type locality for species
  • †Amyda mira – type locality for species
• †Amynodon
  • †Amynodon advenus
• †Anacardites
  • †Anacardites schinoloxus
• Anaclinia – tentative report
• †Anacodon
  • †Anacodon nexus – type locality for species
  • †Anacodon ursidens
• Anamirta – or unidentified comparable form
  • †Anamirta milleri
• †Anaptomorphus
  • †Anaptomorphus aemulus – type locality for species
  • †Anaptomorphus westi – type locality for species
• Anas
  • †Anas acuta

  • 

    Anas clypeata
  • †Anas crecca
  • Anas platyrhynchos
  • †Anas schneideri – type locality for species
• †Anatella
  • †Anatella tacita – type locality for species
• †Anconodon
  • †Anconodon cochranensis
  • †Anconodon gidleyi
• †Anemia
  • †Anemia elongata
• †Anemorhysis
  • †Anemorhysis natronensis – type locality for species
  • †Anemorhysis pattersoni – type locality for species
  • †Anemorhysis sublettensis – type locality for species
  • †Anemorhysis wortmani – type locality for species
• †Anilioides
  • †Anilioides nebraskensis
• †Anisonchus
  • †Anisonchus sectorius
  • †Anisonchus willeyi – type locality for species
• †Ankylodon
  • †Ankylodon annectens – or unidentified comparable form
• †Anniealexandria – type locality for genus
  • †Anniealexandria gansi – type locality for species
• Anobium
  • †Anobium deceptum – type locality for species
  • †Anobium lignitum – type locality for species
  • †Anobium ovale – type locality for species
• †Anolbanolis – type locality for genus
  • †Anolbanolis banalis – type locality for species
  • †Anolbanolis geminus – type locality for species
• †Anomoemys
  • †Anomoemys lewisi

• 

  †Anosteira
  • †Anosteira ornata
  • †Anosteira radulina – type locality for species
  • †Anosteira trionychoides
• †Antherophagus
  • †Antherophagus priscus – type locality for species
• Anthonomus
  • †Anthonomus revictus – type locality for species
  • †Anthonomus soporus – type locality for species
• †Antiacodon
  • †Antiacodon pygmaeus – type locality for species
  • †Antiacodon vanvaleni – type locality for species
  • †Antiacodon venustus – type locality for species

• 

  Antilocapra
  • †Antilocapra americana
• Apalone
  • †Apalone extensa – type locality for species
  • †Apalone heteroglypta – type locality for species
  • †Apalone postera – type locality for species
• †Apatemys
  • †Apatemys bellulus – type locality for species
  • †Apatemys bellus
  • †Apatemys chardini – or unidentified comparable form
  • †Apatemys hendryi – type locality for species
  • †Apatemys rodens
• †Aphaena
  • †Aphaena rotundipennis – type locality for species
• †Apheliscus – type locality for genus
  • †Apheliscus chydaeus – type locality for species
  • †Apheliscus insidiosus
  • †Apheliscus nitidus
  • †Apheliscus wapitiensis – type locality for species
• †Aphelops
  • †Aphelops megalodus
• †Aphronorus
  • †Aphronorus fraudator
  • †Aphronorus orieli – type locality for species
  • †Aphronorus ratatoski – type locality for species
• †Apodosauriscus – type locality for genus
  • †Apodosauriscus minutus – type locality for species
  • †Apodosauriscus thermophilus – type locality for species
• †Apriculus
  • †Apriculus praeteritus – type locality for species
• †Apternodus
  • †Apternodus brevirostris – type locality for species
  • †Apternodus dasophylakas – type locality for species
  • †Apternodus gregoryi – type locality for species
  • †Apternodus iliffensis
  • †Apternodus major – type locality for species
• Aquila
  • †Aquila antiqua – type locality for species

  • 

    Aquila chrysaetos
• Aralia
  • †Aralia notata
  • †Aralia serrulata
  • †Aralia wrightii
• †Araliophyllum
  • †Araliophyllum quina
• Araneus
• †Arapahovius
  • †Arapahovius advena – type locality for species
  • †Arapahovius gazini – type locality for species
• Araucaria
  • †Araucaria longifolia
• †Archaeocyon
  • †Archaeocyon falkenbachi
  • †Archaeocyon leptodus
• †Archaeolagus
  • †Archaeolagus emeraldensis

• 

  †Archaeotherium
  • †Archaeotherium minimus
  • †Archaeotherium mortoni
  • †Archaeotherium palustris – type locality for species
• †Archaerhineura – type locality for genus
  • †Archaerhineura mephitis – type locality for species
• Arcoa^[1]
  • †Arcoa lindgreni – type locality for species^[1]
• †Arctocyon
  • †Arctocyon ferox
  • †Arctocyon mumak
• †Arctodontomys
  • †Arctodontomys nuptus
  • †Arctodontomys simplicidens
  • †Arctodontomys wilsoni – type locality for species

• 

  †Arctodus
  • †Arctodus simus
• †Arctostaphylos
  • †Arctostaphylos elliptica
• †Arctostylops
  • †Arctostylops steini
• †Arecipites
  • †Arecipites tenuiexinous
• †Arenahippus
  • †Arenahippus aemulor – type locality for species
  • †Arenahippus pernix – type locality for species
• †Arfia
  • †Arfia junnei
  • †Arfia opisthotoma
  • †Arfia shoshoniensis
  • †Arfia zele – type locality for species
• Aristolochia
  • †Aristolochia mortua
• †Armintodelphys
  • †Armintodelphys blacki
  • †Armintodelphys dawsoni
• †Armintomys
  • †Armintomys tullbergi
• †Arpadosaurus – type locality for genus
  • †Arpadosaurus gazinorum – type locality for species
  • †Arpadosaurus sepulchralis – type locality for species
• †Artimonius
  • †Artimonius nocerai
  • †Artimonius witteri
• Artocarpus – tentative report
  • †Artocarpus quercoides
• †Asarkina
  • †Asarkina quadrata – type locality for species
• †Asiabradypus – or unidentified comparable form
• Asio
  • †Asio flammeus
  • Asio otus
• †Asplenium
  • †Asplenium delicatula
  • †Asplenium eoligniticum
  • †Asplenium eolignitum
  • †Asplenium erosum
  • †Asplenium iddingsi
  • †Asplenium remotidens
• †Astephus
• †Asterotrygon

  • 

    †Asterotrygon maloneyi
• Astronium
  • †Astronium truncatum
• †Athyana
  • †Athyana balli
• †Aulolithomys
  • †Aulolithomys bounites
  • †Aulolithomys vexilliames – type locality for species
• †Auroralestes
  • †Auroralestes simpsoni
• †Auxontodon
• †Averrhoites
  • †Averrhoites affinis
• †Avunculus
  • †Avunculus didelphodonti – or unidentified comparable form
• †Axestemys – type locality for genus
  • †Axestemys byssina – type locality for species
  • †Axestemys cerevisia – type locality for species
  • †Axestemys salebrosa – type locality for species
  • †Axestemys uintaensis – type locality for species
• †Aycrossia
  • †Aycrossia lovei
• Aythya
  • Aythya collaris
• Azolla
  • †Azolla cretacea
• †Azygonyx
  • †Azygonyx ancylion – type locality for species
  • †Azygonyx grangeri
  • †Azygonyx xenicus – type locality for species

• †Babibasiliscus – type locality for genus
  • †Babibasiliscus alxi – type locality for species
• †Baena
  • †Baena arenosa – type locality for species
• †Bahndwivici – type locality for genus
  • †Bahndwivici ammoskius – type locality for species
• †Baioconodon
  • †Baioconodon denverensis – or unidentified comparable form
  • †Baioconodon middletoni – type locality for species
  • †Baioconodon nordicus
  • †Baioconodon wovokae
• †Baiotomeus
  • †Baiotomeus douglassi
  • †Baiotomeus lamberti
• †Baltemys – type locality for genus
  • †Baltemys staurogastros – type locality for species
• †Baptemys
  • †Baptemys wyomingensis – type locality for species
• †Barbouromeryx – or unidentified comparable form

• 

  †Barylambda
  • †Barylambda churchilli – type locality for species
  • †Barylambda faberi
• †Bathornis
  • †Bathornis fricki – type locality for species
• †Bathygenys
  • †Bathygenys alpha
  • †Bathygenys hedlundae
• †Bathyopsis
  • †Bathyopsis fissidens

• 

  †Batodonoides
  • †Batodonoides vanhouteni – type locality for species
• †Batrachosauroides – tentative report
• Bauhinia
  • †Bauhinia wyomingana
  • †Bauhinia wyomingiana
• †Beilschmiedia
  • †Beilschmiedia eocenica
• †Berchemiopsis
  • †Berchemiopsis paucidentata
• †Beringiaphyllum
  • †Beringiaphyllum cupanioides
• †Berosus
  • †Berosus sexstriatus – type locality for species
  • †Berosus tenuis – type locality for species
• †Bessoecetor
  • †Bessoecetor septentrionalis
• Betula
  • †Betula iddingsi
  • †Betula stevensoni
  • †Betula stevensonii
• Biomphalaria
• Bison

  • 

    †Bison bison
• †Bisonalveus – type locality for genus
  • †Bisonalveus browni – type locality for species
  • †Bisonalveus holtzmani – type locality for species
• †Blechnum
  • †Blechnum anceps
• Bledius
  • †Bledius adamus – type locality for species
  • †Bledius faecorum – type locality for species
• †Blickomylus
  • †Blickomylus galushai

• 

  †Boavus – type locality for genus
  • †Boavus brevis – type locality for species
  • †Boavus idelmani – type locality for species
  • †Boavus occidentalis – type locality for species
• Boletina
  • †Boletina paludivaga – type locality for species
  • †Boletina umbratica – type locality for species
• †Bootherium
  • †Bootherium bombifrons
• †Borealosuchus
  • †Borealosuchus formidabilis
  • †Borealosuchus wilsoni – type locality for species
• †Botauroides – type locality for genus
  • †Botauroides parvus – type locality for species
• †Bouromeryx
• †Boverisuchus
  • †Boverisuchus vorax
• †Bownomomys – type locality for genus^[2]
  • †Bownomomys americanus – type locality for species. Formerly known as Teilhardina americana.^[2]
  • †Bownomomys crassidens – type locality for species. Formerly known as Teilhardina crassidens.^[2]
• †Boysia – or unidentified comparable form
  • †Boysia phenacodorum
• †Brachianodon
  • †Brachianodon westorum – type locality for species

• 

  †Brachycrus
  • †Brachycrus rusticus
  • †Brachycrus sweetwaterensis
  • †Brachycrus vaughani
• †Brachyerix
  • †Brachyerix macrotis
• †Brachyhyops
  • †Brachyhyops viensis
  • †Brachyhyops wyomingensis – type locality for species
• †Brachyrhynchocyon
  • †Brachyrhynchocyon dodgei
  • †Brachyrhynchocyon intermedius
• †Brachyuranochampsa – type locality for genus
  • †Brachyuranochampsa eversolei – type locality for species
• Bracon
  • †Bracon laminarum – type locality for species
• Branta

  • 

    †Branta canadensis
• †Bridgeremys
  • †Bridgeremys pusilla – type locality for species
• †Brontops
• †Browniea
  • †Browniea serrata
• †Bryophyte – or unidentified related form
• Bubo
  • †Bubo virginianus
• †Bunophorus
  • †Bunophorus etsagicus
  • †Bunophorus grangeri
  • †Bunophorus macropternus
  • †Bunophorus robustus
  • †Bunophorus sinclairi – type locality for species
• †Bunrsera
  • †Bunrsera inaequalateralis
• Buteo
  • †Buteo jamaicensis
  • †Buteo lagopus
  • †Buteo regalis – or unidentified comparable form

• 

  Buteogallus

• †Caedocyon
  • †Caedocyon tedfordi – type locality for species
• †Caenolambda – type locality for genus
  • †Caenolambda jepseni – type locality for species
  • †Caenolambda pattersoni – type locality for species

• 

  †Caenopus
  • †Caenopus yoderensis – type locality for species
• †Caesalpinia
  • †Caesalpinia flumen-viridensis
  • †Caesalpinia pecorae
• †Caesalpinites
  • †Caesalpinites falcata – type locality for species
• †Calamagras
  • †Calamagras angulatus – or unidentified comparable form
  • †Calamagras platyspondyla
  • †Calamagras primus – type locality for species
  • †Calamagras weigeli
• †Calamospiza
  • †Calamospiza melanocorys
• †Calandrites
  • †Calandrites cineratius
  • †Calandrites defessus
• †Calcardea – type locality for genus
  • †Calcardea junnei – type locality for species
• Calidris

  • 

    †Calidris melanotos
• †Callomyia
  • †Callomyia torporata – type locality for species
• †Callospilopteron – type locality for genus
  • †Callospilopteron ocellatum – type locality for species
• †Calycites
  • †Calycites ardtunensis
  • †Calycites hexaphylla
  • †Calycites mikanoides
  • †Calycites polysepala
  • †Calycites RR58 informal
  • †Calycites RR71 informal
• †Camelops
  • †Camelops hesternus – or unidentified comparable form
• †Canarium
  • †Canarium californicum
• †Canavalia
  • †Canavalia diuturna
• Canis

  • 

    †Canis dirus
  • †Canis latrans
  • †Canis lupus
• †Cantius
  • †Cantius abditus – type locality for species
  • †Cantius frugivorus
  • †Cantius mckennai
  • †Cantius nunienus
  • †Cantius ralstoni
  • †Cantius simonsi – type locality for species
  • †Cantius torresi
  • †Cantius trigonodus – type locality for species
• †Capacikala
  • †Capacikala parvus – type locality for species
• Capella
  • †Capella gallinago
• †Carabites
  • †Carabites kincaidi – type locality for species
• Caracara

  • 

    †Caracara plancus
• †Cardichelyon – type locality for genus
  • †Cardichelyon rogerwoodi – type locality for species
• †Cardiolophus
  • †Cardiolophus radinskyi – type locality for species
  • †Cardiolophus semihians
• Cardiospermum

  • 

    †Cardiospermum coloradensis
• Carduelis
• †Carpites
  • †Carpites newberryana
  • †Carpites pedunculatus
  • †Carpites verrucosus
• †Carpodaptes
  • †Carpodaptes hazelae
  • †Carpodaptes hobackensis
  • †Carpodaptes jepseni
  • †Carpodaptes rosei
  • †Carpodaptes stonleyi
• †Carpolestes
  • †Carpolestes dubius – type locality for species
  • †Carpolestes nigridens

  • 

    †Carpolestes simpsoni – type locality for species
• †Carpolithes
  • †Carpolithes osseus
• Carya
  • †Carya antiquorum
  • †Carya veripites
  • †Carya viridifluminipites
• Castanea
  • †Castanea intermedia
  • †Castanea pulchella
• Castor
  • †Castor peninsulatus
• †Catopsalis
  • †Catopsalis alexanderi
  • †Catopsalis calgariensis

• 

  Cedrela
  • †Cedrela trainii
• †Cedrelospermum
  • †Cedrelospermum lineatum
  • †Cedrelospermum nervosum
• †Cedrobaena – type locality for genus
  • †Cedrobaena putorius
• †Cedrocherus
  • †Cedrocherus aceratus – type locality for species
  • †Cedrocherus ryani – type locality for species
• †Cedromus
  • †Cedromus wardi

• 

  †Celastrus
  • †Celastrus culveri
  • †Celastrus ellipticus
  • †Celastrus inaequalis
  • †Celastrus winchesteri
• †Celliforma
  • †Celliforma spirifer
• Celtis
  • †Celtis aspera
  • †Celtis newberryi
  • †Celtis peracuminata
  • †Celtis phenacodorum
• †Centetodon
  • †Centetodon bacchanalis
  • †Centetodon bembicophagus
  • †Centetodon chadronensis
  • †Centetodon hendryi
  • †Centetodon magnus
  • †Centetodon marginalis
  • †Centetodon neashami – type locality for species
  • †Centetodon patratus
  • †Centetodon pulcher
• †Centrinus
  • †Centrinus diruptus – type locality for species
• †Centrocercus
  • †Centrocercus urophasianus
• †Cephalogale
• †Ceratophyllum
  • †Ceratophyllum muricatum

• 

  †Ceratosuchus
  • †Ceratosuchus burdoshi
• Cercidiphyllum
  • †Cercidiphyllum arcticum
  • †Cercidiphyllum articum
  • †Cercidiphyllum BB21 informal
  • †Cercidiphyllum BB34-52 informal
  • †Cercidiphyllum genetrix
  • †Cercidiphyllum tiny winged seeds informal
  • †Cercidiphyllum tiny wingedseeds informal

• 

  †Cercopis
  • †Cercopis astricta – type locality for species
• †Cercopites – type locality for genus
  • †Cercopites calliscens – type locality for species
  • †Cercopites umbratilis – type locality for species
• †Ceutholestes
  • †Ceutholestes dolosus
• †Chadrolagus
  • †Chadrolagus emryi
• †Chaetoptelea
  • †Chaetoptelea microphylla
  • †Chaetoptelea pseudofulva – tentative report
• †Chalicomomys
  • †Chalicomomys willwoodensis – type locality for species

• 

  †Champsosaurus
  • †Champsosaurus gigas
• †Chaneya

  • 

    †Chaneya tenuis
• Chara
• Charadrius
  • †Charadrius montanus
  • †Charadrius vociferus
• Charina
  • †Charina prebottae
• Cheilosia
  • †Cheilosia ampla – type locality for species
  • †Cheilosia scudderi
• †Chelomophrynus – type locality for genus
  • †Chelomophrynus bayi – type locality for species
• †Chilostigma – tentative report
  • †Chilostigma ostracoderma
• †Chiromyoides
  • †Chiromyoides caesor – type locality for species
  • †Chiromyoides major – type locality for species
  • †Chiromyoides minor – type locality for species
  • †Chiromyoides potior
• Chironomus
  • †Chironomus septus – type locality for species

• 

  †Chisternon
  • †Chisternon hebraicum – type locality for species
  • †Chisternon undatum – type locality for species
• †Chlororhysis
  • †Chlororhysis incomptus – type locality for species
  • †Chlororhysis knightensis – type locality for species
• †Choctawius – or unidentified comparable form
• †Cholula
  • †Cholula triguttata – type locality for species
• †Choragus
  • †Choragus fictilis – type locality for species
• †Chordeiles

  • 

    †Chordeiles minor
• †Chriacus
  • †Chriacus badgleyi
  • †Chriacus baldwini
  • †Chriacus gallinae
  • †Chriacus katrinae
  • †Chriacus oconostotae
  • †Chriacus pelvidens
• †Chumashius
• †Cicadula
  • †Cicadula saxosa – type locality for species
• †Cimolestes
• †Cinnamomophyllum
  • †Cinnamomophyllum RR19 informal

• 

  Cinnamomum
  • †Cinnamomum sezannense
  • †Cinnamomum spectabilis
• Circus
  • †Circus cyaneus
• †Cissites
  • †Cissites rocklandensis
• Cissus
  • †Cissus haguei
  • †Cissus marginata
  • †Cissus marginatus
• †Cixius – tentative report
  • †Cixius hesperidum – type locality for species

• 

  Cladrastis
  • †Cladrastis GR579 informal
  • †Cladrastis GR580 informal
• †Claenodon
  • †Claenodon montanensis
• †Cnemidaria
  • †Cnemidaria magna
• †Coccothraustes
  • †Coccothraustes vespertinus

• 

  Cocculus
  • †Cocculus flabella
• †Coelidia
  • †Coelidia wyomingensis – type locality for species
• Colaptes
  • †Colaptes auratus
• †Colodon
  • †Colodon woodi
• †Colpocherus
• †Colpoclaenus
  • †Colpoclaenus keeferi – type locality for species
  • †Colpoclaenus procyonoides – or unidentified comparable form
• Colymbus
  • †Colymbus nigricollis
• †Compsemys
  • †Compsemys victa
• †Conacodon
  • †Conacodon cophater – or unidentified comparable form
  • †Conacodon delphae

• 

  †Coniophis
  • †Coniophis carinatus – type locality for species
  • †Coniophis platycarinatus – type locality for species
• †Copecion
  • †Copecion brachypternus
  • †Copecion davisi
• †Copedelphys
  • †Copedelphys stevensoni
• †Copelemur
  • †Copelemur australotutus – type locality for species
  • †Copelemur praetutus
  • †Copelemur tutus
• †Copemys
  • †Copemys longidens
• †Coriphagus
  • †Coriphagus encinensis – or unidentified comparable form
  • †Coriphagus montanus
• †Corizus – tentative report
  • †Corizus guttatus – type locality for species

• 

  †Cormocyon
  • †Cormocyon haydeni
• Cornus
  • †Cornus hyperborea
  • †Cornus nebrascensis
  • †Cornus newberryi
  • †Cornus wrightii
• Corvus
  • †Corvus brachyrhynchos
  • †Corvus corax
• †Corylites
  • †Corylites FW01 informal
• †Corylus
  • †Corylus insignis
  • †Corylus macquarryi
• Corymbites
  • †Corymbites velatus – type locality for species

• 

  †Coryphodon
  • †Coryphodon armatus
  • †Coryphodon eocaenus
  • †Coryphodon lobatus
  • †Coryphodon proterus
  • †Coryphodon radians
• †Cranea
  • †Cranea wyomingensis
• Crataegus
• †Credneria
  • †Credneria daturaefolia – tentative report
  • †Credneria pachyphylla
• †Cristadjidaumo
  • †Cristadjidaumo skinneri – type locality for species
• Crocodylus

  • 

    †Crocodylus affinis – type locality for species
  • †Crocodylus ziphodon – type locality for species
• †Cryptocephalus
  • †Cryptocephalus vetustus – type locality for species
• Cryptorhynchus
  • †Cryptorhynchus annosus – type locality for species
• Cryptotis
• Culex
  • †Culex damnatorum – type locality for species
• †Cupanieidites
  • †Cupanieidites inaequalis
  • †Cupanieidites inaequatis
• †Cupidinimus
  • †Cupidinimus whitlocki
• †Cycadopites
  • †Cycadopites follicularis
• Cyclocarya
• †Cyclurus
  • †Cyclurus fragosus
• †Cylindrodon
  • †Cylindrodon natronensis – type locality for species
  • †Cylindrodon solarborus – type locality for species

• 

  †Cynarctoides
  • †Cynarctoides acridens
  • †Cynarctoides harlowi
  • †Cynarctoides luskensis – type locality for species
• †Cyperacites
  • †Cyperacites angustior
  • †Cyperacites filiferus
  • †Cyperacites giganteus
• †Cyriacotherium
  • †Cyriacotherium argyreum – type locality for species
  • †Cyriacotherium psamminum – type locality for species
• †Cyrilavis
  • †Cyrilavis olsoni – type locality for species
• †Cyrtomenus
  • †Cyrtomenus concinnus – type locality for species

• †Dalbergia
• †Daphoenictis

• 

  †Daphoenodon
  • †Daphoenodon falkenbachi – type locality for species
  • †Daphoenodon niobrarensis
  • †Daphoenodon skinneri – type locality for species
  • †Daphoenodon superbus
• †Daphoenus
  • †Daphoenus lambei
• †Dartonius
  • †Dartonius jepseni

• 

  Dasyatis
• †Davidia
  • †Davidia antiqua
• †Dawsonicyon – type locality for genus
  • †Dawsonicyon isami – type locality for species
• †Dawsonomys
  • †Dawsonomys woodi
• †Dawsonophis – type locality for genus
  • †Dawsonophis wyomingensis – type locality for species
• †Debeya
• †Decatoma
  • †Decatoma antiqua – type locality for species
• †Delotrochanter
  • †Delotrochanter major – type locality for species
• Dendragapus

  • 

    †Dendragapus obscurus
• †Dendropanax
  • †Dendropanax latens
• †Dennstaedia
  • †Dennstaedia americana
• †Dennstaedtia
  • †Dennstaedtia americana
• †Dennstaedtiopsis
  • †Dennstaedtiopsis aerenchymata
• †Desmatippus
  • †Desmatippus tyleri
• †Desmatochoerus
  • †Desmatochoerus hatcheri
  • †Desmatochoerus megalodon
• †Desmatoclaenus
  • †Desmatoclaenus mearae
• †Desmatolagus
  • †Desmatolagus schizopetrus
• †Desmatotherium
  • †Desmatotherium intermedius
• †Desmocyon
  • †Desmocyon thomsoni
• †Devallia – tentative report
  • †Devallia montana
• †Diacocherus
  • †Diacocherus meizon – type locality for species
  • †Diacocherus minutus

• 

  †Diacodexis
  • †Diacodexis ilicis
  • †Diacodexis kelleyi
  • †Diacodexis kellyi
  • †Diacodexis metsiacus
  • †Diacodexis minutus
  • †Diacodexis primus
  • †Diacodexis secans
  • †Diacodexis woltonensis – type locality for species
• †Diacodon
  • †Diacodon celatus
• †Diaplegma
  • †Diaplegma obdormitum – type locality for species
• †Diatryma – type locality for genus
  • †Diatryma gigantea – type locality for species

• 

  †Diceratherium
  • †Diceratherium annectens
  • †Diceratherium armatum
  • †Diceratherium tridactylum
• Dicotylophyllum
  • †Dicotylophyllum anomalum
  • †Dicotylophyllum mercerensis
• Dicranomyia
  • †Dicranomyia primitiva
  • †Dicranomyia rhodolitha – type locality for species
• Dicrostonyx
• †Didelphodontine
• †Didelphodus
  • †Didelphodus absarokae
  • †Didelphodus altidens
• †Didymictis
  • †Didymictis altidens
  • †Didymictis leptomylus
  • †Didymictis protenus
  • †Didymictis proteus
  • †Didymictis vancleveae – or unidentified comparable form
• †Dillerlemur
  • †Dillerlemur pagei
  • †Dillerlemur robinettei – type locality for species
• †Dilophodon
  • †Dilophodon destitutus – type locality for species
  • †Dilophodon minusculus

• 

  †Dinictis
  • †Dinictis felina
• †Dinohyus
• †Diospyros
  • †Diospyros brachysepala
  • †Diospyros haguei
  • †Diospyros lamarensis
• †Dipassalus
  • †Dipassalus oryctes
• †Diplobunops
  • †Diplobunops matthewi
• †Diplocynodon
• †Diplolophus
  • †Diplolophus insolens – type locality for species

• 

  †Diplomystus
  • †Diplomystus dentatus
• †Dipoides
  • †Dipoides stirtoni
• †Dipsalidictis
  • †Dipsalidictis aequidens
  • †Dipsalidictis krausei – type locality for species
  • †Dipsalidictis platypus – type locality for species
  • †Dipsalidictis transiens
• †Dipsalodon
  • †Dipsalodon churchillorum
  • †Dipsalodon matthewi – type locality for species

• 

  Dipteronia
  • †Dipteronia GR551 informal
  • †Dipteronia insignis
• Discus
• †Dissacus
  • †Dissacus argenteus – type locality for species
  • †Dissacus longaevus
  • †Dissacus navajovius
  • †Dissacus praenuntius
• †Distylium
  • †Distylium eocenica
• †Dithelysia
  • †Dithelysia amorensis

• 

  Dolichopus
• †Dombeya
  • †Dombeya novimundi
• †Domnina
  • †Domnina gradata – or unidentified comparable form
• †Domninoides
  • †Domninoides valentinensis – or unidentified comparable form
• †Dorraletes
  • †Dorraletes diminutivus
• †Douglassciurus
  • †Douglassciurus jeffersoni
• †Drimys
• Dryocoetes
  • †Dryocoetes carbonarius – type locality for species
  • †Dryocoetes impressus
• †Dryomomys – type locality for genus
  • †Dryomomys dulcifer – type locality for species
  • †Dryomomys szalayi – type locality for species

• 

  Dryopteris
  • †Dryopteris lakesi
  • †Dryopteris longipetiolatum
  • †Dryopteris meeteetseana
  • †Dryopteris serrata
  • †Dryopteris weedii
  • †Dryopteris xantholithensis
• †Dunnophis
  • †Dunnophis microechinis – type locality for species
  • †Dunnophis microechinus
• †Dysagrion – type locality for genus
  • †Dysagrion fredericii – type locality for species
  • †Dysagrion lakesii – type locality for species
  • †Dysagrion packardii – type locality for species

• 

  †Echmatemys
  • †Echmatemys haydeni
  • †Echmatemys lativertebralis
  • †Echmatemys megaulax
  • †Echmatemys rivalis – type locality for species
  • †Echmatemys septaria
  • †Echmatemys testudinea
  • †Echmatemys wyomingensis
• †Eclytus
  • †Eclytus lutatus – type locality for species

• 

  †Ectocion
  • †Ectocion cedrus – type locality for species
  • †Ectocion collinus – type locality for species
  • †Ectocion major – or unidentified comparable form
  • †Ectocion mediotuber – type locality for species
  • †Ectocion osbornianus
  • †Ectocion parvus
  • †Ectocion superstes
• †Ectoconus
  • †Ectoconus cavigellii – type locality for species
  • †Ectoconus ditrigonus
• †Ectoganus
  • †Ectoganus bighornensis
  • †Ectoganus copei
  • †Ectoganus gliriformes
  • †Ectoganus gliriformis
  • †Ectoganus lobdelli
• †Ectopistes

  • 

    †Ectopistes migratorius
• †Ectopocynus
  • †Ectopocynus antiquus – type locality for species
  • †Ectopocynus intermedius – type locality for species
• †Ectypodus
  • †Ectypodus aphronorus
  • †Ectypodus childei – or unidentified comparable form
  • †Ectypodus hazeni – type locality for species
  • †Ectypodus laytoni – type locality for species
  • †Ectypodus lovei
  • †Ectypodus musculus
  • †Ectypodus powelli – type locality for species
  • †Ectypodus simpsoni
  • †Ectypodus szalayi
  • †Ectypodus tardus
• †Elaeodendron
  • †Elaeodendron polymorphum
• †Ellipsodon
  • †Ellipsodon lemuroides – or unidentified comparable form
• †Elphidotarsius
  • †Elphidotarsius florencae – or unidentified comparable form
  • †Elphidotarsius shotgunensis
• †Elpidophorus
  • †Elpidophorus elegans
  • †Elpidophorus minor – or unidentified comparable form
• †Elwynella – type locality for genus
  • †Elwynella oreas – type locality for species
• †Enhydrocyon
  • †Enhydrocyon basilatus
  • †Enhydrocyon crassidens
  • †Enhydrocyon pahinsintewakpa
• Enochrus
  • †Enochrus primaevus – type locality for species

• 

  †Entelodon
  • †Entelodon coarctatus – or unidentified comparable form
• †Entomolestes – type locality for genus
  • †Entomolestes grangeri – type locality for species
  • †Entomolestes westgatei – type locality for species
• †Entomophontes – type locality for genus
  • †Entomophontes hutchisoni – type locality for species
  • †Entomophontes incrustatus – type locality for species
• †Entoptychus

• 

  †Eobasileus
  • †Eobasileus cornutus
• †Eobucco
  • †Eobucco brodkorbi
• †Eocalopteryx
  • †Eocalopteryx atavina – type locality for species
• †Eoceornis – type locality for genus
  • †Eoceornis ardetta – type locality for species
• †Eoconodon
  • †Eoconodon copanus
• †Eocrex – type locality for genus
  • †Eocrex primus – type locality for species
• †Eodiploglossus – type locality for genus
  • †Eodiploglossus borealis – type locality for species
• †Eoerianthus
  • †Eoerianthus multispinosa
• †Eoformica
  • †Eoformica pinguis – type locality for species
• †Eofringillirostrum – type locality for genus^[3]
  • †Eofringillirostrum boudreauxi – type locality for species^[3]
• †Eoglyptosaurus
  • †Eoglyptosaurus donohoei – type locality for species
• Eohiodon

• 

  †Eohippus
  • †Eohippus cristatus
• †Eoictops – type locality for genus
  • †Eoictops novaceki – type locality for species
• †Eoliarus – tentative report
  • †Eoliarus lutensis – type locality for species
• †Eomoropus
  • †Eomoropus amarorum
  • †Eomoropus anarsius
• †Eopodagrion – type locality for genus
  • †Eopodagrion abortivum – type locality for species
  • †Eopodagrion scudderi – type locality for species
• †Eorhinophrynus
  • †Eorhinophrynus septentrionalis – type locality for species
• †Eoryctes – type locality for genus
  • †Eoryctes melanus – type locality for species
• †Eostangeria
  • †Eostangeria pseudopteris
• †Eostrix
  • †Eostrix martinellii – type locality for species

• 

  †Eotitanops
  • †Eotitanops borealis
• †Eotylopus
  • †Eotylopus reedi – type locality for species
• †Eozygodactylus – type locality for genus
  • †Eozygodactylus americanus – type locality for species
• †Epicaerus
  • †Epicaerus dilapsus – type locality for species
  • †Epicaerus effossus – type locality for species
  • †Epicaerus exanimis – type locality for species
  • †Epicaerus fodinarum
  • †Epicaerus saxatilis – type locality for species
  • †Epicaerus subterraneus
  • †Epicaerus terrosus – type locality for species

• 

  †Epihippus
  • †Epihippus gracilis
• †Epitriplopus
  • †Epitriplopus uintensis
• †Epoicotherium
  • †Epoicotherium unicum
• †Equisetum
  • †Equisetum canaliculatum
  • †Equisetum deciduum
  • †Equisetum FW21 informal
  • †Equisetum haguei
• Equus
  • †Equus conversidens
• Eremophila
  • †Eremophila alpestris

• 

  Erythrina
  • †Erythrina roanensis – type locality for species
• Esox
  • †Esox kronneri – type locality for species
• †Esthonyx
  • †Esthonyx acutidens
  • †Esthonyx bisulcatus
  • †Esthonyx gunnelli
  • †Esthonyx spatularius
• †Eucastor
• †Eucommia
  • †Eucommia serrata
• †Eudaemonema
  • †Eudaemonema cuspidata

• 

  Eugenia
  • †Eugenia americana
• †Eugnamptus
  • †Eugnamptus decemsatus – type locality for species
  • †Eugnamptus grandaevus
• †Euhapsis
  • †Euhapsis ellicottae
• †Eumys
  • †Eumys elegans
• †Euparius
  • †Euparius elusus – type locality for species
  • †Euparius repertus – type locality for species
• Euphagus
  • †Euphagus cyanocephalus
  • †Euphagus magnirostris
• †Euproteaciphyllum
  • †Euproteaciphyllum minutum

• 

  †Eusmilus
  • †Eusmilus sicarius
• Eutamias
• †Eutypomys
  • †Eutypomys parvus
• †Exostinus
  • †Exostinus lancensis – or unidentified comparable form

• Fagus
  • †Fagus antipofii
  • †Fagus undulata
• Falco
  • †Falco columbarius
  • †Falco falconella – type locality for species

  • 

    †Falco mexicanus
  • †Falco rusticolus
  • †Falco sparverius
• †Ficarasites – type locality for genus
  • †Ficarasites stigmaticum – type locality for species
• Ficus
  • †Ficus affinis
  • †Ficus artocarpoides
  • †Ficus asiminaefolia
  • †Ficus deformata
  • †Ficus densifolia
  • †Ficus haguei
  • †Ficus planicostata
  • †Ficus shastensis – tentative report
  • †Ficus subtruncata
  • †Ficus tiliaefolia – tentative report
  • †Ficus ungeri
• †Firmianites – type locality for genus
  • †Firmianites aterrimus – type locality for species
• †Florentiamys
  • †Florentiamys kinseyi – type locality for species
  • †Florentiamys loomisi – type locality for species

• 

  †Fluvioviridavis – type locality for genus
  • †Fluvioviridavis platyrhamphus – type locality for species
• †Foekenia
  • †Foekenia catenulata
• †Fortuna
  • †Fortuna marsilioides – or unidentified comparable form
• †Franimys
  • †Franimys ambos
  • †Franimys amherstensis – type locality for species
  • †Franimys buccatus
• †Fraxinoipollenis
  • †Fraxinoipollenis variabilis
• †Fraxinoipollenites
  • †Fraxinoipollenites pachyexinous
  • †Fraxinoipollenites variabilis
• †Fraxinopollenites
  • †Fraxinopollenites variabilis

• 

  †Fraxinus
  • †Fraxinus eocenica
  • †Fraxinus eocinica
  • †Fraxinus wrightii
• †Fulgora
  • †Fulgora granulosa – type locality for species
  • †Fulgora populata – type locality for species

• †Gagadon
  • †Gagadon minimonstrum
• †Galbreathia
  • †Galbreathia novellus
• †Galecyon
  • †Galecyon mordax
• Galerita
  • †Galerita marshii – type locality for species

• 

  †Gallinuloides – type locality for genus
  • †Gallinuloides wyomingensis – type locality for species
• Gastrocopta
• Gastrodonta
• †Gaultia – type locality for genus
  • †Gaultia silvaticus – type locality for species
• †Gazinius
  • †Gazinius amplus
  • †Gazinius bowni – type locality for species
• †Gazinocyon
  • †Gazinocyon vulpeculus
• †Gelastops
  • †Gelastops joni – type locality for species
  • †Gelastops parcus
• †Geranoides – type locality for genus
  • †Geranoides jepseni – type locality for species
• †Geringophis
  • †Geringophis depressus
• Gerrhonotus – or unidentified comparable form
• Ginkgo

  • 

    †Ginkgo adiantoides
• †Gleditsia – or unidentified related form
  • †Gleditsia RR29 informal
• †Gleicheniidites
• †Glypta
  • †Glypta transversalis – type locality for species
• †Glyptosaurus – type locality for genus
  • †Glyptosaurus agmodon – type locality for species
  • †Glyptosaurus obtusidens – type locality for species
  • †Glyptosaurus rhodinos – type locality for species
  • †Glyptosaurus sphenodon – type locality for species
  • †Glyptosaurus sylvestris – type locality for species
• Glyptostrobus

  • 

    †Glyptostrobus europaeus
  • †Glyptostrobus nordenskioldi
• †Goinophis – tentative report
• †Gomphochelys – type locality for genus
  • †Gomphochelys nanus – type locality for species
• †Goniacodon
  • †Goniacodon levisanus – type locality for species
• †Goniodontomys
  • †Goniodontomys disjunctus
• Gopherus
  • †Gopherus laticuneus
• †Gracilocyon
  • †Gracilocyon rosei
  • †Gracilocyon winkleri
• †Grangerella
• †Gregorymys
  • †Gregorymys formosus
  • †Gregorymys riggsi – type locality for species
• †Grewiopsis – tentative report
  • †Grewiopsis aldersoni
• †Griphomys
• Grus
  • †Grus canadensis
  • †Grus marshi – type locality for species
• Gulo

  • 

    †Gulo gulo
• †Gymnetron
  • †Gymnetron lecontei – type locality for species
• †Gymnocladus
  • †Gymnocladus hesperia
• Gyraulus – or unidentified comparable form

• †Habrosaurus
  • †Habrosaurus dilatus
• †Hadrianus
  • †Hadrianus allabiatus – type locality for species
  • †Hadrianus quadratus – type locality for species
• †Hammapteryx – type locality for genus
  • †Hammapteryx reticulata – type locality for species

• 

  †Hapalodectes
  • †Hapalodectes anthracinus
  • †Hapalodectes leptognathus
• †Hapalorestes
  • †Hapalorestes lovei – type locality for species
• †Haplaletes
  • †Haplaletes disceptatrix
  • †Haplaletes pelicatus – type locality for species
• †Haploconus
• †Haplodontosaurus
  • †Haplodontosaurus excedens
• †Haplolambda
  • †Haplolambda quinni
• †Haplomylus
  • †Haplomylus bozemanensis – type locality for species
  • †Haplomylus palustris
  • †Haplomylus scottianus – type locality for species
  • †Haplomylus simpsoni
  • †Haplomylus speirianus
  • †Haplomylus zalmouti

• 

  †Harpagolestes
  • †Harpagolestes macrocephalus – type locality for species
• †Harpalodon
  • †Harpalodon sylvestris – or unidentified comparable form
• †Harrymys
  • †Harrymys irvini
  • †Harrymys woodi
• †Helaletes – type locality for genus
  • †Helaletes nanus – type locality for species
• †Heliscomys
  • †Heliscomys hatcheri
  • †Heliscomys mcgrewi
  • †Heliscomys ostranderi
  • †Heliscomys vetus – or unidentified comparable form
• †Helix
  • †Helix evanstonensis
  • †Helix sinclairi

• 

  †Helodermoides
  • †Helodermoides tuberculatus
• †Helohyus
  • †Helohyus lentus
  • †Helohyus milleri – type locality for species
  • †Helohyus plicodon – type locality for species
• †Hemiacodon
  • †Hemiacodon casamissus – type locality for species
  • †Hemiacodon engardae – type locality for species
  • †Hemiacodon gracilis

• 

  †Hemiauchenia
• †Hemipsalodon
  • †Hemipsalodon grandis
• Hemitelia
  • †Hemitelia magna
• †Hemithlaeus
  • †Hemithlaeus harbourae
  • †Hemithlaeus josephi
• †Hendryomeryx
  • †Hendryomeryx wilsoni
• †Heptacodon
• †Heptodon
  • †Heptodon calciculus
  • †Heptodon posticus

• 

  †Herpetotherium
  • †Herpetotherium innominatum – type locality for species
  • †Herpetotherium knighti
  • †Herpetotherium youngi – or unidentified comparable form
• †Hesperocyon
  • †Hesperocyon gregarius
• †Hesperopetes
  • †Hesperopetes thoringtoni – type locality for species
• †Hesperosorex
  • †Hesperosorex lovei – type locality for species
• †Heteraletes
  • †Heteraletes leotanus
• †Hexacodus
  • †Hexacodus pelodes
  • †Hexacodus uintensis
• †Hicoria
  • †Hicoria antiqua
  • †Hicoria crescentia
  • †Hicoria culveri
• Hirundo – or unidentified comparable form
  • †Hirundo pyrrhonota
• †Holospira
• †Homacodon
  • †Homacodon vagans – type locality for species
• †Homalota
  • †Homalota recisa – type locality for species
• †Homogalax
  • †Homogalax protapirinus
• †Honrovits – type locality for genus
  • †Honrovits tsuwape – type locality for species

• 

  †Hoplophoneus
  • †Hoplophoneus mentalis
  • †Hoplophoneus primaevus
• †Hovenia
  • †Hovenia oregonensis – or unidentified comparable form
• †Huerfanodon
  • †Huerfanodon polecatensis – type locality for species
• †Hummelichelys
  • †Hummelichelys annae – type locality for species
  • †Hummelichelys ellipticus
  • †Hummelichelys grangeri – type locality for species
  • †Hummelichelys guttatus – type locality for species
• †Hutchemys
  • †Hutchemys rememdium

• 

  †Hyaenodon
  • †Hyaenodon crucians
  • †Hyaenodon horridus
  • †Hyaenodon megaloides
  • †Hyaenodon montanus
  • †Hyaenodon mustelinus
  • †Hyaenodon venturae
  • †Hyaenodon vetus
• Hydrangea
  • †Hydrangea antica
  • †Hydrangea GR537 informal
• Hydrobia – report made of unidentified related form or using admittedly obsolete nomenclature

• 

  Hydrobius
  • †Hydrobius confixus – type locality for species
  • †Hydrobius decineratus – type locality for species
• †Hydrochus
  • †Hydrochus relictus – type locality for species
• †Hydromystria
  • †Hydromystria expansa
• †Hylobius
  • †Hylobius packardii – type locality for species
  • †Hylobius provectus – type locality for species

• 

  †Hyopsodus
  • †Hyopsodus aemulor
  • †Hyopsodus latidens
  • †Hyopsodus lepidus – type locality for species
  • †Hyopsodus loomisi
  • †Hyopsodus lysitensis
  • †Hyopsodus mentalis
  • †Hyopsodus minor
  • †Hyopsodus minusculus – type locality for species
  • †Hyopsodus miticulus
  • †Hyopsodus paulus – type locality for species
  • †Hyopsodus pauxillus – type locality for species
  • †Hyopsodus powellianus
  • †Hyopsodus simplex
  • †Hyopsodus tonksi – type locality for species
  • †Hyopsodus uintensis
  • †Hyopsodus walcottianus
  • †Hyopsodus wortmani
• †Hypertragulus
  • †Hypertragulus calcaratus
• †Hypisodus
  • †Hypisodus alacer
  • †Hypisodus minimus

• 

  †Hypohippus
  • †Hypohippus affinis
• †Hypolagus
  • †Hypolagus parviplicatus – or unidentified comparable form
• †Hyporhina
  • †Hyporhina tertia
• †Hypsiops
  • †Hypsiops breviceps
• †Hyrachyus
  • †Hyrachyus eximius
  • †Hyrachyus modestus – type locality for species

• 

  †Hyracodon
  • †Hyracodon nebraskensis
  • †Hyracodon petersoni
  • †Hyracodon priscidens
• †Hyracotherium
  • †Hyracotherium vasacciense

• 

  †Icaronycteris – type locality for genus
  • †Icaronycteris index – type locality for species
• †Ignacius
  • †Ignacius clarkforkensis – type locality for species
  • †Ignacius fremontensis
  • †Ignacius frugivorus
  • †Ignacius graybullianus
• †Iguanavus – type locality for genus
  • †Iguanavus exilis – type locality for species
• †Indusia
  • †Indusia calculosa – type locality for species
• †Insulapollenites
  • †Insulapollenites leboensis
  • †Insulapollenites rugulatus
• †Intyrictis
  • †Intyrictis vanvaleni
• †Iridodon – type locality for genus
  • †Iridodon datzae – type locality for species

• 

  †Ischyromys
  • †Ischyromys typus
  • †Ischyromys veterior
• †Isectolophus
  • †Isectolophus latidens
  • †Isectolophus radinskyi – type locality for species
• †Isoetites
  • †Isoetites horridus
• †Iulus
  • †Iulus telluster – type locality for species

• †Jepsenella
  • †Jepsenella praepropera
• †Jepsibaena
  • †Jepsibaena minor – type locality for species
• †Joffrea
  • †Joffrea BB20 informal
  • †Joffrea FW50 informal
• †Judithemys
  • †Judithemys backmani – or unidentified comparable form
• †Juglandicarya
• †Juglandiphyllites
  • †Juglandiphyllites glabra
• Juglans
  • †Juglans crescentia
  • †Juglans laurifolia
  • †Juglans rugosa
  • †Juglans schimperi

• 

  †Juncitarsus – type locality for genus
  • †Juncitarsus gracillimus – type locality for species
• Junco – or unidentified comparable form
  • †Junco hyemalis
• †Junglandaceae

• †Kalmia
  • †Kalmia elliptica
• †Kalobatippus
  • †Kalobatippus agatensis
  • †Kalobatippus avus

• 

  †Knightia
  • †Knightia eocaena
• †Knightomys
  • †Knightomys cremneus
  • †Knightomys cuspidatus
  • †Knightomys depressus
  • †Knightomys huerfanensis
  • †Knightomys minor
  • †Knightomys senior
• Koelreuteria
  • †Koelreuteria viridifluminis
• †Koniaryctes
  • †Koniaryctes paulus – type locality for species
• †Kydia – or unidentified related form
  • †Kydia FW61 informal

• †Labidolemur
  • †Labidolemur kayi
  • †Labidolemur major – type locality for species
  • †Labidolemur serus
  • †Labidolemur soricoides
• Laccobius
  • †Laccobius elongatus – type locality for species
• †Laevigatosporites

• 

  †Lagopus
  • †Lagopus leucurus – or unidentified comparable form
• †Lambdotherium
  • †Lambdotherium popoagicum
• †Lambertocyon
  • †Lambertocyon eximius
  • †Lambertocyon gingerichi – type locality for species
• Lanius
  • †Lanius ludovicianus
• Larus – or unidentified comparable form
• †Lastrea
  • †Lastrea goldiana
• Lathrobium
  • †Lathrobium abscessum – type locality for species
• †Laurinoxylon
  • †Laurinoxylon pulchellum
• †Laurophyllum
  • †Laurophyllum caudatum
  • †Laurophyllum perseanum

• 

  Laurus
  • †Laurus californica
  • †Laurus grandis
  • †Laurus montana
  • †Laurus perdita
  • †Laurus primigenia – tentative report
  • †Laurus princeps
  • †Laurus socialis
• †Leguminosites
  • †Leguminosites coloradensis
  • †Leguminosites lamarensis
  • †Leguminosites lesquereuxiana
  • †Leguminosites regularis – type locality for species
• Leiocephalus
• †Leipsanolestes
  • †Leipsanolestes siegfriedti

• 

  Lepisosteus
  • †Lepisosteus glaber – or unidentified comparable form
  • †Lepisosteus occidentalis
• †Leptacodon
  • †Leptacodon donkroni
  • †Leptacodon munusculum
  • †Leptacodon packi – type locality for species
  • †Leptacodon tener
• †Leptarctus – or unidentified comparable form

• 

  †Leptauchenia
  • †Leptauchenia decora
  • †Leptauchenia major
• †Leptictis
  • †Leptictis dakotensis
• †Leptocyon
  • †Leptocyon gregorii
• †Leptolambda
  • †Leptolambda schmidti

• 

  †Leptomeryx
  • †Leptomeryx esulcatus
  • †Leptomeryx evansi
  • †Leptomeryx mammifer
  • †Leptomeryx semicinctus
  • †Leptomeryx speciosus
  • †Leptomeryx yoderi – type locality for species
• †Leptoreodon
• †Leptotomus
  • †Leptotomus guildayi
  • †Leptotomus parvus – type locality for species
• †Leptotragulus
  • †Leptotragulus clarki – or unidentified comparable form
  • †Leptotragulus medius
  • †Leptotragulus ultimus
• Lepus
• Lepyrus – tentative report
  • †Lepyrus evictus – type locality for species
• †Lestophis
  • †Lestophis anceps – type locality for species
  • †Lestophis crassus – type locality for species
• †Leucosticte
  • †Leucosticte arctoa
• †Limaconyssus – type locality for genus
  • †Limaconyssus habrus – type locality for species
• †Limalophus
  • †Limalophus compositus
  • †Limalophus contractus – type locality for species

• 

  †Limnocyon
  • †Limnocyon cuspidens – type locality for species
  • †Limnocyon medius
  • †Limnocyon potens – type locality for species
  • †Limnocyon velox – type locality for species
  • †Limnocyon verus – type locality for species
• †Limnoecus

• 

  †Limnofregata – type locality for genus
  • †Limnofregata azygosternon – type locality for species
  • †Limnofregata hutchisoni – type locality for species
• Lindera
  • †Lindera obtusata
  • †Lindera varifolia – type locality for species
• †Lisserpeton
  • †Lisserpeton bairdi
• †Listronotus
  • †Listronotus muratus – type locality for species
• †Litaletes
  • †Litaletes disjunctus
  • †Litaletes ondolinde
• †Lithexorista – type locality for genus
  • †Lithexorista scudderi – type locality for species
• †Lithohypoderma

  • 

    †Lithohypoderma ascarides - type locality for species
• †Lithophis – type locality for genus
  • †Lithophis sargenti – type locality for species
• †Lithophysa – type locality for genus
  • †Lithophysa tumulta – type locality for species
• †Lithopsis – type locality for genus
  • †Lithopsis elongata – type locality for species
  • †Lithopsis fimbriata – type locality for species

• 

  †Lithornis
  • †Lithornis plebius – type locality for species
  • †Lithornis promiscuus – type locality for species
• †Lithotorus – type locality for genus
  • †Lithotorus cressoni – type locality for species
• †Litocherus
  • †Litocherus lacunatus – type locality for species
  • †Litocherus notissimus
  • †Litocherus zygeus – type locality for species
• †Litolagus
  • †Litolagus molidens
• †Litolestes
  • †Litolestes ignotus – type locality for species
• †Litomylus
  • †Litomylus dissentaneus – type locality for species
  • †Litomylus ishami – type locality for species
  • †Litomylus scaphicus – type locality for species
• †Litoyoderimys
  • †Litoyoderimys auogoleus
• †Lophiotherium
  • †Lophiotherium vasacciensis – type locality for species
• †Lophiparamys
  • †Lophiparamys debequensis
  • †Lophiparamys murinus
  • †Lophiparamys woodi
• †Lophocion^[4]
  • †Lophocion grangeri – type locality for species^[4]
• †Loveina – type locality for genus
  • †Loveina minuta
  • †Loveina sheai
  • †Loveina wapitiensis
  • †Loveina zephyri – type locality for species
• †Loxolophus
  • †Loxolophus criswelli
  • †Loxolophus faulkneri – type locality for species
  • †Loxolophus hyattianus – or unidentified comparable form
  • †Loxolophus priscus
• †Lucashyus – type locality for genus
  • †Lucashyus coombsae – type locality for species
• †Lyctocoris – tentative report
  • †Lyctocoris terreus – type locality for species
• Lygodium
  • †Lygodium coloradense
  • †Lygodium kaulfussi
• Lynx

  • 

    †Lynx lynx – tentative report
• †Lystra – tentative report
  • †Lystra leei – type locality for species
  • †Lystra richardsoni – type locality for species

• †Maceopolipollenites
  • †Maceopolipollenites amplus
  • †Maceopolipollenites leboensis
  • †Maceopolipollenites rotundus
  • †Maceopolipollenites tenuipolus
  • †Maceopolipollenites triorbicularis
• †Macginitiea
  • †Macginitiea gracilis
  • †Macginitiea wyomingensis
• †Machaeroides
  • †Machaeroides eothen
  • †Machaeroides simpsoni – type locality for species
• †Machaerosaurus
  • †Machaerosaurus torrejonensis
• Macrocranion
  • †Macrocranion junnei – type locality for species
  • †Macrocranion nitens
  • †Macrocranion robinsoni
• †Macrotarsius
  • †Macrotarsius siegerti – type locality for species

• 

  Magnolia
  • †Magnolia borealis
  • †Magnolia californica
  • †Magnolia culveri
  • †Magnolia magnifica
  • †Magnolia magnifolia
  • †Magnolia microphylla
  • †Magnolia pollardi
  • †Magnolia spectabilis
• †Maiorana
  • †Maiorana ferrisensis – type locality for species
  • †Maiorana noctiluca
• †Malapoenna
  • †Malapoenna cuneata
  • †Malapoenna lamarensis
• †Malaquiferus
  • †Malaquiferus tourteloti – type locality for species
• †Malfelis – type locality for genus
  • †Malfelis badwaterensis – type locality for species
• †Mammacyon
  • †Mammacyon ferocior – type locality for species
• †Mammuthus

  • 

    †Mammuthus columbi
• Marmota
• †Marsholestes
  • †Marsholestes dasypelix – type locality for species
• †Mattimys
  • †Mattimys kalicola
• †Megacerops
  • †Megacerops osborni – type locality for species
• †Megadelphus
  • †Megadelphus lundeliusi
• †Megalagus
  • †Megalagus brachyodon
  • †Megalagus primitivus
  • †Megalagus turgidus
• †Megalesthonyx
  • †Megalesthonyx hopsoni

• 

  †Megalictis
  • †Megalictis ferox
  • †Megalictis petersoni
• †Melanosaurus – type locality for genus
  • †Melanosaurus maximus – type locality for species
• †Melastomites
  • †Melastomites montanensis
• †Meliakrouniomys
  • †Meliakrouniomys skinneri
• †Meliosma
  • †Meliosma flexuosa
  • †Meliosma longifolia

• 

  †Meniscotherium
  • †Meniscotherium chamense
  • †Meniscotherium priscum
  • †Meniscotherium tapiacetum
  • †Meniscotherium tapiacitum
• †Menisperimites
  • †Menisperimites parvareolatus
• †Menispermites
  • †Menispermites limacioides – type locality for species
  • †Menispermites parvareolatus

• 

  †Menoceras
  • †Menoceras arikarense
  • †Menoceras barbouri
• †Menops
  • †Menops heloceras
  • †Menops marshi – or unidentified comparable form
• †Mentoclaenodon
  • †Mentoclaenodon acrogenius – type locality for species
• Mergus
  • †Mergus merganser

• 

  †Merychippus
  • †Merychippus coloradense
  • †Merychippus insignis – or unidentified comparable form
  • †Merychippus primus
• †Merychyus
  • †Merychyus arenarum
  • †Merychyus crabilli
  • †Merychyus elegans – or unidentified comparable form
  • †Merychyus minimus
• †Merycobunodon – tentative report
  • †Merycobunodon walshi – type locality for species
• †Merycochoerus
  • †Merycochoerus chelydra
  • †Merycochoerus magnus
  • †Merycochoerus matthewi

• 

  †Merycodus
  • †Merycodus sabulonis – or unidentified comparable form
  • †Merycodus warreni – or unidentified comparable form
• †Merycoides
  • †Merycoides longiceps
  • †Merycoides pariogonus
• †Merycoidodon
  • †Merycoidodon culbertsoni – type locality for species
  • †Merycoidodon major
  • †Merycoidodon presidioensis – or unidentified comparable form
• †Mesatirhinus
  • †Mesatirhinus megarhinus
• †Mesocyon – report made of unidentified related form or using admittedly obsolete nomenclature
  • †Mesocyon temnodon
• †Mesodma
  • †Mesodma ambigua – type locality for species
  • †Mesodma formosa
  • †Mesodma garfieldensis – or unidentified comparable form
  • †Mesodma hensleighi
  • †Mesodma pygmaea

• 

  †Mesohippus
  • †Mesohippus bairdi
  • †Mesohippus westoni – or unidentified comparable form
• †Mesomeryx – or unidentified comparable form
  • †Mesomeryx grangeri
• †Mesonyx
  • †Mesonyx obtusidens – type locality for species
• †Mesoreodon
  • †Mesoreodon chelonyx
  • †Mesoreodon minor – type locality for species
• †Mesoscalops
  • †Mesoscalops scopelotemos

• 

  †Metacheiromys
  • †Metacheiromys dasypus – type locality for species
  • †Metacheiromys marshi – type locality for species
• †Metadjidaumo
  • †Metadjidaumo hendryi – type locality for species
• †Metamynodon
  • †Metamynodon planifrons – or unidentified comparable form
• †Metanoiamys
  • †Metanoiamys paradoxus
• †Metarhinus
• Metasequoia
  • †Metasequoia occidentalis
• †Metatomarctus
  • †Metatomarctus canavus

• 

  †Miacis
  • †Miacis deutschi
  • †Miacis exiguus
  • †Miacis latidens
  • †Miacis medius
  • †Miacis parvivorus – type locality for species
  • †Miacis petilus
  • †Miacis vorax
• †Michenia
• Micrasema – tentative report
  • †Micrasema tessellatum – type locality for species
• †Microclaenodon
  • †Microclaenodon assurgens
• †Microcosmodon
  • †Microcosmodon conus – type locality for species
  • †Microcosmodon rosei – type locality for species
• †Micromomys
  • †Micromomys antelucanus
  • †Micromomys silvercouleei – type locality for species
• †Microparamys
  • †Microparamys cheradius
  • †Microparamys dubius
  • †Microparamys hunterae
  • †Microparamys minutus

• 

  Microphysula – or unidentified comparable form
• †Micropternodus
  • †Micropternodus borealis
• †Microsus
  • †Microsus cuspidatus – type locality for species
• †Microsyops
  • †Microsyops angustidens – type locality for species
  • †Microsyops annectens
  • †Microsyops cardiorestes
  • †Microsyops elegans – type locality for species
  • †Microsyops knightensis
  • †Microsyops latidens
  • †Microsyops scottianus
• Microtus

  • 

    †Microtus pennsylvanicus
• Mictomys
  • †Mictomys vetus
• †Mimatuta
  • †Mimatuta makpialutae
  • †Mimatuta minuial – type locality for species
• †Mimetodon
  • †Mimetodon churchilli – type locality for species
  • †Mimetodon silberlingi
• †Mimoperadectes
  • †Mimoperadectes houdei – type locality for species
  • †Mimoperadectes labrus – type locality for species
• †Mimosites
  • †Mimosites coloradensis
• †Mimotricentes
  • †Mimotricentes fremontensis – type locality for species

• 

  †Miniochoerus
  • †Miniochoerus affinis – type locality for species
  • †Miniochoerus chadronensis – type locality for species
  • †Miniochoerus forsythae
  • †Miniochoerus gracilis
• †Minippus
  • †Minippus index
• †Mioclaenus
  • †Mioclaenus opisthacus – or unidentified comparable form
  • †Mioclaenus turgidus
• †Miocyon
  • †Miocyon major – or unidentified comparable form
• †Mioheteromys
  • †Mioheteromys amplissimus
• †Miohippus
  • †Miohippus obliquidens
• †Miolabis
  • †Miolabis fissidens
• †Miomustela

• 

  †Mioplosus
• †Miospermophilus
  • †Miospermophilus wyomingensis
• †Miotapirus
  • †Miotapirus harrisonensis – type locality for species
• †Miotylopus
  • †Miotylopus gibbi
  • †Miotylopus leonardi
  • †Miotylopus taylori – type locality for species

• 

  †Miracinonyx
  • †Miracinonyx studeri
• †Mithrandir
  • †Mithrandir gillianus
• †Mitostylus
  • †Mitostylus seculorum – type locality for species
• †Mixodectes
  • †Mixodectes malaris
• Mnemosyne
  • †Mnemosyne terrentula – type locality for species
• †Mojavemys
  • †Mojavemys magnumarcus
• †Monosaulax
  • †Monosaulax curtus – or unidentified comparable form
• †Moropus
  • †Moropus hollandi
• Morus
  • †Morus montanensis
• †Musophyllum
  • †Musophyllum complicatum
• Mustela
  • †Mustela americana
  • †Mustela nigripes
• Mycetobia – tentative report
  • †Mycetobia terricola – type locality for species
• †Mylanodon – type locality for genus
  • †Mylanodon rosei – type locality for species

• 

  Myrica
  • †Myrica lamarensis
  • †Myrica scottii
  • †Myrica wardii
• †Myrmecoboides
  • †Myrmecoboides montanensis
• Myrmica
• †Myrtophyllum
  • †Myrtophyllum torreyi
• †Mysops
  • †Mysops fraternus
  • †Mysops minimus – type locality for species
  • †Mysops parvus – type locality for species
• †Mytonolagus
  • †Mytonolagus petersoni
  • †Mytonolagus wyomingensis – type locality for species
• †Mytonomys
  • †Mytonomys coloradensis
  • †Mytonomys wortmani

• †Namatomys
  • †Namatomys erythrus – type locality for species
  • †Namatomys lloydi
• †Nannodectes
  • †Nannodectes gazini – type locality for species
  • †Nannodectes gidleyi
  • †Nannodectes intermedius – type locality for species
  • †Nannodectes simpsoni – type locality for species
• †Nanodelphys
  • †Nanodelphys hunti
• †Nanomomys
  • †Nanomomys thermophilus
• †Nanotragulus
  • †Nanotragulus loomisi – type locality for species
  • †Nanotragulus ordinatus
• †Naocephalus – type locality for genus
  • †Naocephalus porrectus – type locality for species
• †Navajovius
  • †Navajovius kohlhaasae
• †Neanis
  • †Neanis schucherti
• †Necrocydnus
  • †Necrocydnus gosiutensis – type locality for species
• †Necygonus – type locality for genus
  • †Necygonus rotundatus – type locality for species
• †Nelumbago
  • †Nelumbago montanum

• 

  †Nelumbo
• †Neocathartes
  • †Neocathartes grallator
• †Neodiacodexis
  • †Neodiacodexis emryi
• †Neoliotomus
  • †Neoliotomus conventus
  • †Neoliotomus ultimus

• 

  Neophrontops
  • †Neophrontops americana
  • †Neophrontops americanus
• †Neoplagiaulax
  • †Neoplagiaulax grangeri – tentative report
  • †Neoplagiaulax hunteri
  • †Neoplagiaulax jepi – type locality for species
  • †Neoplagiaulax mckennai – type locality for species
  • †Neoplagiaulax nelsoni
• †Neothanes
  • †Neothanes testeus – type locality for species
• Neotoma
• †Neovulpavus
  • †Neovulpavus washakius
• †Nexuotapirus
  • †Nexuotapirus marslandensis
• †Niglarodon
• †Niptomomys
  • †Niptomomys doreenae
  • †Niptomomys favorum – type locality for species
  • †Niptomomys thelmae
• †Nonomys
  • †Nonomys simplicidens
• †Nordenskioldia
  • †Nordenskioldia borealis
• †Nosodendron
  • †Nosodendron tritavum – type locality for species
• †Notharctus
  • †Notharctus robinsoni – type locality for species
  • †Notharctus robustior

  • 

    †Notharctus tenebrosus – type locality for species
  • †Notharctus venticolus
• †Notogoneus
• †Notomorpha – type locality for genus
  • †Notomorpha garmanii – type locality for species
  • †Notomorpha gravis – type locality for species
  • †Notomorpha testudinea – type locality for species
• †Notoparamys – tentative report
  • †Notoparamys blochi – type locality for species
• †Nototamias – or unidentified comparable form
• †Nucifraga
  • †Nucifraga columbiana
• Numenius
  • †Numenius americanus

  • 

    †Numenius borealis
• †Nyctea
  • †Nyctea scandiaca
• †Nyctitherium
  • †Nyctitherium christopheri
  • †Nyctitherium gunnelli – type locality for species
  • †Nyctitherium serotinum – type locality for species
  • †Nyctitherium velox
• †Nyssa
  • †Nyssa alata
  • †Nyssa borealis

• Ochotona

  • 

    †Ochotona princeps
• Ocotea
  • †Ocotea coloradensis
  • †Ocotea FW03 informal
• †Odaxosaurus
  • †Odaxosaurus jepseni – or unidentified comparable form
  • †Odaxosaurus piger
• †Ogmophis
  • †Ogmophis microcompactus – or unidentified comparable form
  • †Ogmophis voorhiesi
• †Oligodontosaurus – type locality for genus
  • †Oligodontosaurus wyomingensis – type locality for species
• †Oligoryctes
  • †Oligoryctes altitalonidus
  • †Oligoryctes cameronensis
• †Oligoscalops – tentative report
• †Oligospermophilus
• †Oligotheriomys
  • †Oligotheriomys senrudi
• †Oliveremys
  • †Oliveremys uintaensis – type locality for species
• †Omalodiscus
• †Omomys
  • †Omomys carteri
  • †Omomys lloydi
• Ondatra
  • †Ondatra meadensis
• †Onoclea
  • †Onoclea hesperia

• 

  †Onychonycteris – type locality for genus
  • †Onychonycteris finneyi – type locality for species
• †Oodectes
  • †Oodectes herpestoides – type locality for species
  • †Oodectes jepseni
• Ophryastes
  • †Ophryastes compactus – type locality for species
• †Opisthotriton
  • †Opisthotriton kayi

• 

  Oreamnos
• †Oreoconus
• †Oreodontoides
  • †Oreodontoides oregonensis
• Oreohelix
  • †Oreohelix megarche
• †Oreolagus
  • †Oreolagus colteri
  • †Oreolagus nebrascensis
• †Oreopanax
  • †Oreopanax elongatum
• †Ormiscus
  • †Ormiscus partitus – type locality for species

• 

  †Orohippus
  • †Orohippus major – type locality for species
  • †Orohippus proteros
  • †Orohippus pumilus – type locality for species
  • †Orohippus sylvaticus
• †Orthogenysuchus – type locality for genus
  • †Orthogenysuchus olseni – type locality for species
• †Osbornodon
  • †Osbornodon brachypus – type locality for species
• †Osmanthus
  • †Osmanthus praemissa

• 

  †Osmunda
  • †Osmunda affinis
• †Osmundacidites
• †Otarocyon
  • †Otarocyon cooki
• †Otiorhynchites
  • †Otiorhynchites fossilis – type locality for species
  • †Otiorhynchites tysoni
• †Otiorhynchus
  • †Otiorhynchus dubius – type locality for species
  • †Otiorhynchus perditus – type locality for species
• †Ototriton – type locality for genus
  • †Ototriton solidus – type locality for species
• †Ourayia
  • †Ourayia hopsoni
  • †Ourayia uintensis
• Ovis

  • 

    †Ovis canadensis
• †Oxyacodon
  • †Oxyacodon agapetillus
  • †Oxyacodon apiculatus
  • †Oxyacodon priscilla
• †Oxyaena
  • †Oxyaena forcipata
  • †Oxyaena gulo
  • †Oxyaena intermedia
  • †Oxyaena lupina
• †Oxyclaenus
  • †Oxyclaenus cuspidatus

• 

  †Oxydactylus
  • †Oxydactylus longipes – or unidentified comparable form
  • †Oxydactylus lulli – type locality for species
  • †Oxydactylus wyomingensis
• †Oxyprimus
  • †Oxyprimus galadrielae – type locality for species
  • †Oxyprimus putorius

• 

  †Pachyaena
  • †Pachyaena gigantea
  • †Pachyaena gracilis
  • †Pachyaena ossifraga
• Pachycondyla
  • †Pachycondyla labandeirai – type locality for species
• †Pachylobius
  • †Pachylobius compressus
• †Palaeanodon
  • †Palaeanodon ignavus
  • †Palaeanodon Ignavus
  • †Palaeanodon nievelti
  • †Palaeanodon parvulus – tentative report
• †Palaearctonyx
  • †Palaearctonyx meadi – type locality for species
• †Palaechthon
  • †Palaechthon alticuspis – or unidentified comparable form
  • †Palaechthon woodi
• †Palaeictops
  • †Palaeictops bicuspis
  • †Palaeictops bridgeri
  • †Palaeictops multicuspis
• †Palaeocarpinus
  • †Palaeocarpinus aspinosa
• †Palaeocarya
  • †Palaeocarya clarnensis
• †Palaeogale
  • †Palaeogale sanguinarius
  • †Palaeogale sectoria

• 

  †Palaeolagus
  • †Palaeolagus burkei
  • †Palaeolagus haydeni
  • †Palaeolagus hypsodus – type locality for species
  • †Palaeolagus intermedius
  • †Palaeolagus philoi
  • †Palaeolagus primus – type locality for species
  • †Palaeolagus temnodon
• †Palaeonictis
  • †Palaeonictis occidentalis
  • †Palaeonictis peloria – type locality for species
  • †Palaeonictis wingi – type locality for species
• †Palaeophasianus – type locality for genus
  • †Palaeophasianus meleagroides – type locality for species
• †Palaeorallus – type locality for genus
  • †Palaeorallus troxelli – type locality for species
• †Palaeoryctes
  • †Palaeoryctes cruoris – type locality for species
  • †Palaeoryctes puercensis
  • †Palaeoryctes punctatus
• †Palaeosinomenium – or unidentified comparable form
  • †Palaeosinomenium venablesii
• †Palaeosinopa
  • †Palaeosinopa didelphoides
  • †Palaeosinopa dorri – type locality for species
  • †Palaeosinopa incerta – type locality for species
  • †Palaeosinopa lacus – type locality for species
  • †Palaeosinopa lutreola
  • †Palaeosinopa veterrima

• 

  †Palaeosyops
  • †Palaeosyops fontinalis
  • †Palaeosyops paludosus – type locality for species
  • †Palaeosyops robustus – type locality for species
• †Palaeotheca
  • †Palaeotheca terrestris – type locality for species
• †Palaeoxantusia – type locality for genus
  • †Palaeoxantusia amara – type locality for species
  • †Palaeoxantusia fera – type locality for species
• †Palatobaena – type locality for genus
  • †Palatobaena bairdi – type locality for species
  • †Palatobaena gaffneyi – type locality for species
• †Palecphora
  • †Palecphora patefacta – type locality for species
• †Palenochtha
  • †Palenochtha minor
  • †Palenochtha weissae – type locality for species
• †Paleoamphiuma – type locality for genus
  • †Paleoamphiuma tetradactylum – type locality for species
• †Paleomyrtinaea
  • †Paleomyrtinaea FW66 informal
• †Paleonelumbo
  • †Paleonelumbo macroloba
• †Paleonuphar
  • †Paleonuphar hesperium
• †Paleotomus
  • †Paleotomus carbonensis – type locality for species
  • †Paleotomus milleri – type locality for species
  • †Paleotomus radagasti
• †Palepidophyma – type locality for genus
  • †Palepidophyma lilliputiana – type locality for species
  • †Palepidophyma paradisa – type locality for species
• Paliurus
  • †Paliurus colombi
• †Palmocarpon
  • †Palmocarpon subcylindricum
• †Pandaniidites
  • †Pandaniidites radicus
• Panthera

  • 

    †Panthera leo
• †Pantolambda
  • †Pantolambda cavirictus
  • †Pantolambda intermedius – or unidentified comparable form
• †Pantolestes
  • †Pantolestes longieundus – type locality for species
  • †Pantolestes natans – or unidentified comparable form
• †Paracathartes
  • †Paracathartes howardae
• †Paracosoryx
  • †Paracosoryx wilsoni
• †Paracynarctus
  • †Paracynarctus kelloggi
• †Paradjidaumo
  • †Paradjidaumo hypsodus
  • †Paradjidaumo trilophus
• †Paraenhydrocyon
  • †Paraenhydrocyon josephi
  • †Paraenhydrocyon robustus
  • †Paraenhydrocyon wallovianus
• †Paraepicrates
  • †Paraepicrates brevispondylus – type locality for species
• †Paraglyptosaurus
  • †Paraglyptosaurus princeps – type locality for species
• †Parahippus
  • †Parahippus pawniensis
  • †Parahippus pristinus – tentative report
  • †Parahippus wyomingensis – type locality for species
• †Paralatindia
  • †Paralatindia saussurei – type locality for species
• †Paramerychyus
  • †Paramerychyus harrisonensis
  • †Paramerychyus relictus
• †Paramys
  • †Paramys adamus – type locality for species
  • †Paramys compressidens
  • †Paramys copei
  • †Paramys delicatior
  • †Paramys delicatus
  • †Paramys excavatus
  • †Paramys leptodus
  • †Paramys pycnus
  • †Paramys relictus
  • †Paramys taurus
• †Parandrita
  • †Parandrita vestita – type locality for species
• †Paranolis – type locality for genus
  • †Paranolis delicatus – type locality for species
• †Paranymphaea
  • †Paranymphaea crassifolia
• †Paranymphea
  • †Paranymphea crassifolia
• †Parapliosaccomys
  • †Parapliosaccomys transversus
• †Paraprionosaurus – type locality for genus
  • †Paraprionosaurus wyomingensis – type locality for species
• †Parapternodus
  • †Parapternodus antiquus – type locality for species
• †Pararyctes
  • †Pararyctes pattersoni – type locality for species
• †Parasauromalus – type locality for genus
  • †Parasauromalus olseni – type locality for species
• †Paraternstroemia
  • †Paraternstroemia hyphovenosa
• †Paratomarctus
  • †Paratomarctus temerarius

• 

  †Paratylopus
  • †Paratylopus labiatus
  • †Paratylopus primaevus
• †Parectypodus
  • †Parectypodus clemensi
  • †Parectypodus lunatus
  • †Parectypodus sinclairi
  • †Parectypodus sylviae
• †Pareumys
  • †Pareumys grangeri
• †Parictis
  • †Parictis dakotensis
  • †Parictis gilpini
  • †Parictis parvus
  • †Parictis personi
• †Paromomys
  • †Paromomys depressidens
  • †Paromomys maturus
• †Parophisaurus
  • †Parophisaurus pawneensis
• †Parvericius
  • †Parvericius montanus
• †Parvileguminophyllum
  • †Parvileguminophyllum coloradensis
• †Parvitragulus
  • †Parvitragulus priscus

• 

  †Patriofelis
  • †Patriofelis ferox – type locality for species
  • †Patriofelis ulta
• †Patriomanis
  • †Patriomanis americanus
• †Pauromys
  • †Pauromys schaubi – type locality for species
• †Peltosaurus
• †Pelycodus
• †Pelycomys
  • †Pelycomys placidus
• †Penetrigonias
  • †Penetrigonias dakotensis
• †Penosphyllum
  • †Penosphyllum cordatum
• †Pentacemylus – tentative report
• †Pentacodon
• †Pentacosmodon
  • †Pentacosmodon pronus – type locality for species
• †Peradectes
  • †Peradectes californicus
  • †Peradectes chesteri
  • †Peradectes elegans – type locality for species
  • †Peradectes protinnaminatus
  • †Peradectes protinnominatus

• 

  †Peratherium
  • †Peratherium comstocki
  • †Peratherium edwardi
  • †Peratherium marsupium
• †Perchoerus
  • †Perchoerus minor
• †Periptychus
  • †Periptychus carinidens
  • †Periptychus coarctatus
• Perognathus
  • †Perognathus furlongi

• 

  Peromyscus
• Persea
  • †Persea brossiana
  • †Persea coriacea – type locality for species
  • †Persea pseudocarolinensis
• †Perseoxylon
  • †Perseoxylon aromaticum
• †Persites
  • †Persites argutus
• †Petauristodon
• †Phalaenoptilus
  • †Phalaenoptilus nuttallii
• †Phareodus
  • †Phareodus encaustus
  • †Phareodus testis
• †Phenacocoelus
  • †Phenacocoelus typus
• †Phenacodaptes
  • †Phenacodaptes sabulosus – type locality for species
• †Phenacodontid

• 

  †Phenacodus
  • †Phenacodus bisonensis – type locality for species
  • †Phenacodus grangeri
  • †Phenacodus intermedius
  • †Phenacodus magnus
  • †Phenacodus matthewi
  • †Phenacodus trilobatus
  • †Phenacodus vortmani
• †Phenacolemur
  • †Phenacolemur fortior – type locality for species
  • †Phenacolemur mcgrewi – type locality for species
  • †Phenacolemur praecox
  • †Phenacolemur shifrae
  • †Phenacolemur simonsi
• Phenacomys
  • †Phenacomys longicaudus
• †Phenolia
  • †Phenolia incapax – type locality for species
• Philhydrus
• †Philodendron – or unidentified related form
  • †Philodendron RR61 informal
• †Philotrox
  • †Philotrox condoni

• 

  †Phlaocyon
  • †Phlaocyon annectens
  • †Phlaocyon leucosteus
  • †Phlaocyon minor
  • †Phlaocyon multicuspus
• †Phoebe
• Phragmites – tentative report
  • †Phragmites latissima
• †Phyllites
  • †Phyllites crassifolia
  • †Phyllites demoresi

• 

  Phyllobius
  • †Phyllobius avus
• Physa
• Phytocrene
  • †Phytocrene sordida
• Pica
  • †Pica pica
• †Piceoerpeton – type locality for genus
  • †Piceoerpeton willwoodense – type locality for species
• †Picrodus
  • †Picrodus calgariensis
  • †Picrodus canpacius
  • †Picrodus silberlingi
• †Picromomys
  • †Picromomys petersonorum – type locality for species

• 

  Pinus
  • †Pinus balli
  • †Pinus florissanti
  • †Pinus GR542 informal
  • †Pinus gracilistrobus
  • †Pinus iddingsi
  • †Pinus Lesquereux
  • †Pinus macrolepis
  • †Pinus premurrayana
  • †Pinus wardii
• †Pipestoneomys
  • †Pipestoneomys bisulcatus – or unidentified comparable form
• Pipilo

  • 

    †Pipilo chlorurus
• †Plagioctenodon
  • †Plagioctenodon krausae
  • †Plagioctenodon rosei
  • †Plagioctenodon savagei
  • †Plagioctenodon thewisseni – type locality for species
• †Plagioctenoides
  • †Plagioctenoides microlestes
  • †Plagioctenoides tombowni
• †Plagiomene
  • †Plagiomene accola
  • †Plagiomene multicuspis
• †Planatus
  • †Planatus raynoldsi

• 

  †Planera
  • †Planera longifolia
• †Planetetherium
  • †Planetetherium mirabile
• †Planetochelys
  • †Planetochelys dithyros
• †Planorbina
  • †Planorbina pseudoammonius
• †Plastomenoides
  • †Plastomenoides lamberti
• †Plastomenus
  • †Plastomenus molopinus
  • †Plastomenus oedemius – type locality for species
  • †Plastomenus tantillus – type locality for species
  • †Plastomenus thomasi
  • †Plastomenus visendus – type locality for species
• †Plataninium
  • †Plataninium haydeni
• †Platanophyllum
  • †Platanophyllum whitneyi

• 

  Platanus
  • †Platanus brownii
  • †Platanus GR552 informal
  • †Platanus gracilis
  • †Platanus guillelmae
  • †Platanus montana
  • †Platanus raynoldsi
  • †Platanus raynoldsii
  • †Platanus wyomingensis
• Platycarya
  • †Platycarya americana
  • †Platycarya BB09 informal
  • †Platycarya castaneopis
  • †Platycarya castaneopsis
• Platynus
  • †Platynus caesus – type locality for species
  • †Platynus senex – type locality for species
• Plecia
  • †Plecia dejecta – type locality for species
  • †Plecia pealei – type locality for species

• 

  †Plesiadapis
  • †Plesiadapis anceps – type locality for species
  • †Plesiadapis churchilli
  • †Plesiadapis cookei
  • †Plesiadapis dubius
  • †Plesiadapis fodinatus – type locality for species
  • †Plesiadapis gingerichi
  • †Plesiadapis praecursor
  • †Plesiadapis rex
  • †Plesiadapis simonsi – type locality for species
• †Plesiolestes
  • †Plesiolestes problematicus – type locality for species
• †Pliophenacomys
  • †Pliophenacomys meadensis
  • †Pliophenacomys primaevus
• †Poabromylus
  • †Poabromylus golzi
• †Poebrodon

• 

  †Poebrotherium
  • †Poebrotherium eximium
  • †Poebrotherium wilsoni
• †Poliomyia – type locality for genus
  • †Poliomyia recta – type locality for species
• †Pollyosbornia
  • †Pollyosbornia altidens – or unidentified comparable form
• Polygyra
• †Pontifactor
  • †Pontifactor bestiola – type locality for species

• 

  Populus
  • †Populus balsamoides
  • †Populus cinnamomoides
  • †Populus daphnogenoides
  • †Populus FW60 informal
  • †Populus glandulifera
  • †Populus meigsii
  • †Populus nebraskana
  • †Populus speciosa
  • †Populus vivaria
  • †Populus wilmattae
  • †Populus wyomingiana
  • †Populus xantholithensis
• Porzana
  • †Porzana carolina
• †Potamogeton
• †Premnoides
  • †Premnoides douglassi

• 

  †Presbyornis
• †Primobucco
  • †Primobucco kistneri
  • †Primobucco mcgrewi
• †Princetonia
  • †Princetonia yalensis
• †Priscacara
• †Priscachara
• †Pristichampsus
• †Probathyopsis
  • †Probathyopsis harrisorum
  • †Probathyopsis lysitensis
  • †Probathyopsis praecursor
• †Problastomeryx
  • †Problastomeryx primus – type locality for species
• †Procaimanoidea
  • †Procaimanoidea kayi – type locality for species
• †Procamelus
  • †Procamelus grandis
• †Procerberus
  • †Procerberus formicarum – or unidentified comparable form
  • †Procerberus grandis – or unidentified comparable form
• †Prochetodon
  • †Prochetodon cavus – type locality for species
  • †Prochetodon foxi
  • †Prochetodon taxus – type locality for species
• †Procydnus – tentative report
  • †Procydnus mamillanus – type locality for species
• †Procynodictis
  • †Procynodictis vulpiceps
• †Prodiacodon
  • †Prodiacodon concordiarcensis – type locality for species
  • †Prodiacodon furor – or unidentified comparable form
  • †Prodiacodon puercensis – or unidentified comparable form
  • †Prodiacodon tauricinerei
• †Proharrymys
  • †Proharrymys schlaikjeri
• †Prolimnocyon
  • †Prolimnocyon antiguus
  • †Prolimnocyon antiquus
  • †Prolimnocyon atavus
  • †Prolimnocyon eerius
  • †Prolimnocyon haematus – type locality for species
• †Promartes
  • †Promartes lepidus
  • †Promartes olcotti
  • †Promartes vantasselensis

• 

  †Promerycochoerus
  • †Promerycochoerus carrikeri
  • †Promerycochoerus superbus
• †Promioclaenus
  • †Promioclaenus acolytus
  • †Promioclaenus pipiringosi – type locality for species
• †Pronemobius
  • †Pronemobius induratus – type locality for species
  • †Pronemobius tertiarius – type locality for species
• †Pronothodectes
  • †Pronothodectes jepi – type locality for species
• †Propalaeanodon – type locality for genus
  • †Propalaeanodon schaffi – type locality for species
• †Proscalops
  • †Proscalops miocaenus
  • †Proscalops secundus – or unidentified comparable form
• †Prosciurus
  • †Prosciurus vetustus
• †Protadjidaumo – tentative report
  • †Protadjidaumo typus
• †Protagras – type locality for genus
  • †Protagras lacustris – type locality for species
• †Protamphipteryx – type locality for genus
  • †Protamphipteryx basalis – type locality for species
• †Prothryptacodon
  • †Prothryptacodon furens
  • †Prothryptacodon hilli – type locality for species
• †Protictis
  • †Protictis agastor – type locality for species
  • †Protictis aprophatos
  • †Protictis haydenianus
  • †Protictis microlestes
  • †Protictis paralus
• †Protoboysia
  • †Protoboysia complicata

• 

  †Protoceras
  • †Protoceras neatodelpha – type locality for species
• †Protochelydra
  • †Protochelydra zangerli – or unidentified comparable form
• †Protochriacus
  • †Protochriacus simplex – or unidentified comparable form
• †Protohippus
  • †Protohippus perditus – or unidentified comparable form
• †Protolabis
  • †Protolabis heterodontus – or unidentified comparable form
• †Protomarctus
  • †Protomarctus optatus
• †Protopsalis
• †Protoptychus
  • †Protoptychus hatcheri
• †Protoreodon
  • †Protoreodon parvus – or unidentified comparable form
  • †Protoreodon petersoni – or unidentified comparable form
  • †Protoreodon pumilus

• 

  †Protorohippus
  • †Protorohippus montanum
  • †Protorohippus venticolum
• †Protoselene – tentative report
  • †Protoselene novissimus – type locality for species
• †Protospermophilus
  • †Protospermophilus kelloggi
• †Protostrix
  • †Protostrix leptosteus
  • †Protostrix saurodosis – type locality for species
• †Prototomus
  • †Prototomus deimos – type locality for species
  • †Prototomus martis – type locality for species
  • †Prototomus phobos
  • †Prototomus robustus
  • †Prototomus secundarius
• †Protungulatum
  • †Protungulatum donnae
  • †Protungulatum gorgun
  • †Protungulatum sloani

• 

  †Protylopus
  • †Protylopus petersoni
• †Provaranosaurus – type locality for genus
  • †Provaranosaurus acutus – type locality for species
  • †Provaranosaurus fatuus – type locality for species
• †Proviverroides
  • †Proviverroides piercei
• †Proxestops
  • †Proxestops silberlingii – type locality for species
• Prunus
  • †Prunus corrugis
  • †Prunus stewarti

• 

  †Pseudaelurus
  • †Pseudaelurus intrepidus
• †Pseudhipparion
  • †Pseudhipparion retrusum
• †Pseudoblastomeryx
  • †Pseudoblastomeryx advena
• †Pseudocemophora
  • †Pseudocemophora antiqua – or unidentified comparable form
• †Pseudocrypturus – type locality for genus
  • †Pseudocrypturus cercanaxius – type locality for species
• †Pseudocylindrodon
  • †Pseudocylindrodon medius
  • †Pseudocylindrodon tobeyi
• †Pseudodesmatochoerus – type locality for genus
  • †Pseudodesmatochoerus hoffmani – type locality for species
• †Pseudolabis
  • †Pseudolabis dakotensis
• †Pseudopalaeocastor
  • †Pseudopalaeocastor osmagnus

• 

  †Pseudoprotoceras
  • †Pseudoprotoceras longinaris
  • †Pseudoprotoceras minor – type locality for species
  • †Pseudoprotoceras taylori
• †Pseudotetonius
  • †Pseudotetonius ambiguus
• †Pseudotheridomys
  • †Pseudotheridomys pagei – or unidentified comparable form
• †Pseudotomus
  • †Pseudotomus hians – type locality for species
  • †Pseudotomus horribilis – type locality for species
  • †Pseudotomus robustus – type locality for species
• †Psilosemys – type locality for genus
  • †Psilosemys wyomingensis – type locality for species
• †Psilota
  • †Psilota tabidosa – type locality for species

• 

  †Psittacotherium
  • †Psittacotherium multifragum
• Ptelea
  • †Ptelea cassioides
• Pteris – or unidentified related form
  • †Pteris silvicola
• Pterocarya
  • †Pterocarya glabra
  • †Pterocarya hispida
  • †Pterocarya macginitii
• †Pteromogoplistes
  • †Pteromogoplistes smithii – type locality for species
• †Pterospermites
  • †Pterospermites haguei

• 

  †Ptilodus
  • †Ptilodus fractus
  • †Ptilodus gnomus
  • †Ptilodus kummae
  • †Ptilodus mediaevus
  • †Ptilodus montanus – or unidentified comparable form
  • †Ptilodus tsosiensis – or unidentified comparable form
  • †Ptilodus wyomingensis – type locality for species
• †Pulverflumen
  • †Pulverflumen magnificum – type locality for species
• Puma
  • †Puma concolor
• Pupilla – or unidentified comparable form
• †Pyramidula
  • †Pyramidula ralstonensis
• †Pyrocyon
  • †Pyrocyon dioctetus

• †Quadratomus
  • †Quadratomus grandis
  • †Quadratomus grossus
  • †Quadratomus sundelli
• †Quercinium
  • †Quercinium knowltoni
  • †Quercinium lamarense

• 

  Quercus
  • †Quercus consimilis – tentative report
  • †Quercus culveri
  • †Quercus cuneatus – type locality for species
  • †Quercus drymeja
  • †Quercus furcinervis
  • †Quercus GR522 informal
  • †Quercus GR575 informal
  • †Quercus greenlandica
  • †Quercus grosidentata
  • †Quercus hesperia
  • †Quercus magnifolia
  • †Quercus olafseni
  • †Quercus petros – type locality for species
  • †Quercus sullyi
  • †Quercus weedii
  • †Quercus yanceyi
• †Quereuxia
  • †Quereuxia angulata

• 

  Quiscalus – or unidentified comparable form

• 

  †Ramoceros
• †Rapamys
  • †Rapamys wilsoni
• †Raphictis
  • †Raphictis gausion – type locality for species
• †Reithroparamyine
• †Reithroparamys
  • †Reithroparamys delicatissimus – type locality for species
  • †Reithroparamys huerfanensis
• †Restes – type locality for genus
  • †Restes rugosus – type locality for species
• †Reticuloidosporites
  • †Reticuloidosporites pseudomurii
• †Rhamnacinium
  • †Rhamnacinium radiatum
• †Rhamnus
  • †Rhamnus cleburni
  • †Rhamnus hirsuta
  • †Rhamnus rectinervis
• Rhineura – type locality for genus
  • †Rhineura hatcherii – type locality for species
• Rhinoclemmys – report made of unidentified related form or using admittedly obsolete nomenclature
  • †Rhinoclemmys terrestris
• Rhus
  • †Rhus mixta – tentative report

  • 

    †Rhus nigricans
• †Rhyssa
  • †Rhyssa juvenis – type locality for species

• 

  †Robinia
  • †Robinia wardi
• Rosa
  • †Rosa hilliae
• †Rymosia
  • †Rymosia strangulata – type locality for species

• 

  Sabal
  • †Sabal grayana
  • †Sabal powelli
• †Sabalitesamesoneuron
  • †Sabalitesamesoneuron RR34 informal
• †Saccoloma
  • †Saccoloma gardneri
• †Sackenia
  • †Sackenia gibbosa – type locality for species
• †Salilx
  • †Salilx longiacuminata

• 

  Salix
  • †Salix angusta
  • †Salix aquilina
  • †Salix cockerelli
  • †Salix elongata – tentative report
  • †Salix lavateri
  • †Salix varians
• †Salpinctes – or unidentified comparable form
  • †Salpinctes obsoletus
• †Salvinia
  • †Salvinia preauriculata
• †Sanctimus
  • †Sanctimus simonisi – type locality for species
  • †Sanctimus stouti – type locality for species
  • †Sanctimus stuartae

• 

  †Saniwa – type locality for genus
  • †Saniwa ensidens – type locality for species
  • †Saniwa major – type locality for species
  • †Saniwa stenodon
• †Sapindaceous
• †Sapindus
  • †Sapindus alatus
  • †Sapindus grandifolioloides
  • †Sapindus grandifoliolus
  • †Sapindus wardii
• Sassafras
  • †Sassafras thermale
• †Scalopoides
• †Scapherpeton
  • †Scapherpeton tectum
• †Scenopagus
  • †Scenopagus curtidens
  • †Scenopagus edenensis
  • †Scenopagus hewettensis – type locality for species
  • †Scenopagus priscus
• †Schaubeumys
  • †Schaubeumys sabrae
• †Schizodontomys
  • †Schizodontomys harkseni
  • †Schizodontomys sulcidens

• 

  †Schoepfia
  • †Schoepfia republicensis
• Sciara
  • †Sciara scopuli – type locality for species
• †Scincoideus
  • †Scincoideus grassator – type locality for species
• Sciomyza – tentative report
  • †Sciomyza disjecta – type locality for species
  • †Sciomyza manca – type locality for species
• †Sciophila
  • †Sciophila hyatti – type locality for species
• †Sciuravus
  • †Sciuravus bridgeri – type locality for species
  • †Sciuravus nitidus – type locality for species
  • †Sciuravus popi – or unidentified comparable form
  • †Sciuravus wilsoni
• †Scottimus
  • †Scottimus ambiguus – or unidentified comparable form
  • †Scottimus kellamorum – type locality for species
  • †Scottimus viduus
• †Selenaletes
  • †Selenaletes scopaeus
• Sequoia
  • †Sequoia couttsiae
  • †Sequoia langsdorfii
  • †Sequoia magnifica

• 

  †Sespia
  • †Sespia nitida
• †Shoshonius
  • †Shoshonius bowni
  • †Shoshonius cooperi
• †Sialia
• †Sifrhippus
  • †Sifrhippus grangeri
  • †Sifrhippus sandrae
• †Sigynorum – type locality for genus
  • †Sigynorum magnadivisus – type locality for species
• †Simoedosaurus
• †Simpsonictis
  • †Simpsonictis jaynanneae – type locality for species
  • †Simpsonictis pegus – type locality for species
  • †Simpsonictis tenuis
• †Simpsonlemur
  • †Simpsonlemur citatus
  • †Simpsonlemur jepseni – or unidentified comparable form
• †Sinclairella
• †Sinomenium – or unidentified related form
  • †Sinomenium RR08 informal

• 

  †Sinopa
  • †Sinopa agilis – type locality for species
  • †Sinopa major – type locality for species
  • †Sinopa minor
  • †Sinopa rapax – type locality for species
  • †Sinopa viverrinus
• †Siphonophoroides
  • †Siphonophoroides antiqua – tentative report
• Siren
  • †Siren dunni – type locality for species
• Sitona
  • †Sitona grandaevus – type locality for species
  • †Sitona paginarum
• Sloanea – or unidentified related form
  • †Sloanea RR18 informal
• †Smilax
  • †Smilax GR550 informal
  • †Smilax lamarensis

• 

  †Smilodectes
  • †Smilodectes gibossus – type locality for species
  • †Smilodectes gracilis – type locality for species
  • †Smilodectes mcgrewi – type locality for species
  • †Smilodectes sororis – type locality for species
• Sorex
  • †Sorex hoyi
• †Sparganium
  • †Sparganium stygium
• †Spathorhynchus – type locality for genus
  • †Spathorhynchus fossorium – type locality for species
  • †Spathorhynchus natronicus
• Spermophilus
  • †Spermophilus primitivus
  • †Spermophilus variegatus
• †Sphacorhysis
  • †Sphacorhysis burntforkensis – type locality for species

• 

  †Sphenocoelus
  • †Sphenocoelus hyognathus
  • †Sphenocoelus uintensis
• Spirodela
  • †Spirodela magna
• †Spiza
  • †Spiza americana
• †Spurimus
  • †Spurimus scotti
  • †Spurimus selbyi
• Stagnicola
• †Staphylinites
  • †Staphylinites obsoletum – type locality for species
• †Stegobium
  • †Stegobium defunctus – type locality for species
• †Steinius
  • †Steinius annectens – type locality for species
  • †Steinius vespertinus
• †Steneofiber
  • †Steneofiber fossor
  • †Steneofiber gradatus
• †Stenocinclis – type locality for genus
  • †Stenocinclis anomala – type locality for species
• †Stenogomphus
  • †Stenogomphus scudderi – type locality for species

• 

  †Stenomylus
  • †Stenomylus gracilis
  • †Stenomylus hitchcocki
  • †Stenomylus keelinensis
• †Stenopelta
  • †Stenopelta punctulata – type locality for species
• Sterculia
  • †Sterculia coloradensis
• †Stibarus
  • †Stibarus quadricuspis
  • †Stibarus yoderensis
• †Stillingia
  • †Stillingia casca
• †Straitopollis
  • †Straitopollis tectatus
• †Strigorhysis – type locality for genus
  • †Strigorhysis bridgerensis – type locality for species
  • †Strigorhysis rugosus
• Sturnella
  • †Sturnella neglecta
• †Stygimys
  • †Stygimys gratus
  • †Stygimys kuszmauli

• 

  †Stylemys
  • †Stylemys nebrascensis
• †Stylinodon
  • †Stylinodon mirus – type locality for species
• †Styrax
  • †Styrax transversa
• †Subhyracodon
  • †Subhyracodon mitis
  • †Subhyracodon occidentalis
• Surnia
  • †Surnia ulula
• †Suzanniwana – type locality for genus
  • †Suzanniwana patriciana – type locality for species
  • †Suzanniwana revenanta – type locality for species
• †Swaindelphys
  • †Swaindelphys cifellii – type locality for species
• †Swainiguanoides – type locality for genus
  • †Swainiguanoides milleri – type locality for species
• †Swartzia
  • †Swartzia wardelii – type locality for species
• Sylvicola – type locality for genus
  • †Sylvicola cadaver – type locality for species
• Sylvilagus
• Symplocos
  • †Symplocos exilis
• Synaptomys
• †Syncolporites
  • †Syncolporites minimus

• 

  †Syndyoceras
  • †Syndyoceras cooki
• †Syntomostylus
  • †Syntomostylus fortis – type locality for species
• Syrphus
• †Systemodon
  • †Systemodon tapirinus
• †Syzygioides
  • †Syzygioides americana

• Tachycineta – or unidentified comparable form
  • †Tachycineta bicolor

• 

  †Taeniolabis
  • †Taeniolabis taoensis
• †Talpavoides
  • †Talpavoides dartoni – type locality for species
• †Talpavus
  • †Talpavus duplus
  • †Talpavus nitidus
  • †Talpavus sullivani – type locality for species
• Tamias
  • †Tamias ateles – or unidentified comparable form
• †Tanymykter
  • †Tanymykter brachyodontus

• 

  †Tapocyon
  • †Tapocyon robustus – or unidentified comparable form
• †Tarka
  • †Tarka stylifera
• †Tatmanius – type locality for genus
  • †Tatmanius szalayi – type locality for species
• Taxidea
  • †Taxidea taxus
• †Taxites
  • †Taxites olriki
• Taxodium
  • †Taxodium olriki
  • †Taxodium olrikii
• †Taxonus
  • †Taxonus nortoni – type locality for species
• †Taxymys
  • †Taxymys lucaris

• 

  †Teilhardina
  • †Teilhardina americana – type locality for species. Late reclassified in the new genus Bownomomys as the species B. americanus.^[2]
  • †Teilhardina brandti – type locality for species
  • †Teilhardina crassidens – type locality for species. Later reclassified as Bownomomys crassidens.^[2]
  • †Teilhardina demissa – type locality for species
  • †Teilhardina gingerichi
  • †Teilhardina mathewi
  • †Teilhardina tenuicula
• †Teleoceras
• †Telmatherium
  • †Telmatherium validum – or unidentified comparable form
  • †Telmatherium validus – type locality for species
• †Telmatrechus
  • †Telmatrechus parallelus – type locality for species
• †Temnocyon
  • †Temnocyon macrogenys – type locality for species
• †Temnotrionyx – type locality for genus
  • †Temnotrionyx manducans – type locality for species
• †Teretrum
  • †Teretrum quiescitum – type locality for species
• †Ternstroemites
  • †Ternstroemites aureavallis
• †Tetigonia
  • †Tetigonia priscomarginata – type locality for species
  • †Tetigonia priscovariegata – type locality for species
• †Tetonius
  • †Tetonius matthewi – type locality for species
• †Tetonoides
  • †Tetonoides pearcei
• †Tetraclaenodon
  • †Tetraclaenodon puercensis
• †Tetrapassalus
  • †Tetrapassalus proius – type locality for species
• †Thamnotettix
  • †Thamnotettix gannetti – type locality for species
  • †Thamnotettix mutilata – type locality for species

• 

  Thelypteris
  • †Thelypteris iddingsi
  • †Thelypteris iddingsii
• †Thinocyon
• †Thisbemys
  • †Thisbemys brevicrista
  • †Thisbemys corrugatus – type locality for species
  • †Thisbemys perditus
• †Thouinia
  • †Thouinia eocenica
• †Thryptacodon
  • †Thryptacodon antiquus
  • †Thryptacodon australis
  • †Thryptacodon barae
  • †Thryptacodon orthogonius – type locality for species
  • †Thryptacodon pseudarctos
• †Thuites
  • †Thuites interruptus
• †Thuja
  • †Thuja interrupta
  • †Thuja interruptus
• †Thylacaelurus
  • †Thylacaelurus montanus – or unidentified comparable form
• †Thylacodon
  • †Thylacodon pusillus

• 

  Tilia
  • †Tilia populifolia
• †Tillodon
  • †Tillodon fodiens – type locality for species
• †Tillomys
  • †Tillomys parvidens – type locality for species
  • †Tillomys senex
• †Tinimomys
  • †Tinimomys graybulliensis
  • †Tinimomys loomisi
  • †Tinimomys tribos – type locality for species
• Tinosaurus – type locality for genus
  • †Tinosaurus pristinus – type locality for species
  • †Tinosaurus stenodon – type locality for species
• Tipula
  • †Tipula sepulchri – type locality for species
  • †Tipula spoliata – type locality for species

• 

  †Titanoides
  • †Titanoides gidleyi – type locality for species
  • †Titanoides major
  • †Titanoides nanus – type locality for species
  • †Titanoides primaevus
• †Titanomyrma

  • 

    †Titanomyrma lubei – type locality for species
• †Torrejonia
  • †Torrejonia sirokyi – type locality for species
• †Toxotherium
  • †Toxotherium hunteri
• Trapa
  • †Trapa angulata
  • †Trapa paulula
• †Tremanotus
  • †Tremanotus angustata
• †Triatriopollenites
  • †Triatriopollenites granulatus
  • †Triatriopollenites granulus
• †Tricalpites
  • †Tricalpites parvus
• †Tricentes
  • †Tricentes subtrigonus
• †Tricolpites
  • †Tricolpites anguloluminosus + bathyreticulatus
  • †Tricolpites anguloluminosus + bothyreticulatus
  • †Tricolpites angulolumonosus + bathyreticulatus
  • †Tricolpites mutabilis
  • †Tricolpites parvus
• †Trigenicus
  • †Trigenicus profectus
• †Trigonias
  • †Trigonias osborni
• †Trigonorhinus
  • †Trigonorhinus pristinus – type locality for species
• Trionyx
  • †Trionyx concentricus – type locality for species
  • †Trionyx thomasii – type locality for species
• †Triplopus
  • †Triplopus cubitalis – type locality for species
  • †Triplopus implicatus – type locality for species
  • †Triplopus obliquidens – or unidentified comparable form

• 

  †Tritemnodon
  • †Tritemnodon strenuus
• †Tritoma
  • †Tritoma binotata – type locality for species
• †Triumfetta
  • †Triumfetta ovata
• †Trochodendroides
  • †Trochodendroides flabella
• †Trogolemur
  • †Trogolemur amplior – type locality for species
  • †Trogolemur fragilis – type locality for species
  • †Trogolemur myodes – type locality for species
• †Trogosus
  • †Trogosus castoridens – type locality for species
  • †Trogosus gazini – type locality for species
  • †Trogosus latidens
• †Tropideres
  • †Tropideres remotus – type locality for species
• †Tropisternus
  • †Tropisternus saxialis – type locality for species
  • †Tropisternus sculptilis – type locality for species
• †Trypodendron
  • †Trypodendron impressus – type locality for species
• †Tsoabichi – type locality for genus
  • †Tsoabichi greenriverensis – type locality for species
• †Tubulodon
  • †Tubulodon atopum
  • †Tubulodon pearcei
  • †Tubulodon taylori
  • †Tubulodon woodi
• Turdus – or unidentified comparable form
  • †Turdus migratorius
• †Tuscahomys
  • †Tuscahomys ctenodactylops – type locality for species
  • †Tuscahomys major – or unidentified comparable form
  • †Tuscahomys walshi – type locality for species
  • †Tuscahomys worlandensis
• †Tylocephalonyx
  • †Tylocephalonyx skinneri
• Tympanuchus

  • 

    †Tympanuchus phasianellus
• Typha – or unidentified related form
• †Tytthaena
  • †Tytthaena lichna
  • †Tytthaena parrisi – type locality for species

• †Uintaceras
  • †Uintaceras radinskyi
• †Uintacyon
  • †Uintacyon asodes
  • †Uintacyon gingerichi
  • †Uintacyon jugulans – type locality for species
  • †Uintacyon massetericus
  • †Uintacyon rudis
• †Uintanius
  • †Uintanius ameghini
  • †Uintanius rutherfurdi
• †Uintasorex
  • †Uintasorex parvulus – type locality for species

• 

  †Uintatherium – type locality for genus
  • †Uintatherium anceps – type locality for species
• †Uintornis – type locality for genus
  • †Uintornis lucaris – type locality for species
  • †Uintornis marionae – type locality for species
• Ulmus
  • †Ulmus microphylla
  • †Ulmus minima – tentative report
  • †Ulmus rhamnifolia
• Unio
• †Unuchinia
  • †Unuchinia diaphanes – type locality for species
  • †Unuchinia dysmathes
• Ursus

  • 

    †Ursus arctos
• †Ustatochoerus
  • †Ustatochoerus medius
• †Utahia
  • †Utahia carina – type locality for species
• †Utemylus
  • †Utemylus serior – type locality for species

• †Valenia
  • †Valenia wilsoni
• †Valenopsalis
  • †Valenopsalis joyneri
• †Vassacyon
  • †Vassacyon bowni – type locality for species
  • †Vassacyon promicrodon
• †Vauquelinia
  • †Vauquelinia comptonifolia
• †Viburnum
  • †Viburnum antiquorum
  • †Viburnum antiquum
  • †Viburnum asperum
• †Vinea – or unidentified comparable form
  • †Vinea pugetensis

• 

  Vitis
  • †Vitis olriki
  • †"Vitis" stantoni^[5]
• †Viverravus
  • †Viverravus acutus
  • †Viverravus acutus/gracilis informal
  • †Viverravus browni
  • †Viverravus gracilis – type locality for species
  • †Viverravus laytoni
  • †Viverravus lutosus
  • †Viverravus minutus – type locality for species
  • †Viverravus politus
  • †Viverravus rosei – type locality for species
  • †Viverravus sicarius
• Viviparus

• 

  †Vulpavus
  • †Vulpavus australis
  • †Vulpavus canavus
  • †Vulpavus farsonensis – type locality for species
  • †Vulpavus hargeri
  • †Vulpavus ovatus – type locality for species
  • †Vulpavus palustris – type locality for species
  • †Vulpavus profectus – type locality for species
  • †Vulpavus simplex
• Vulpes

  • 

    †Vulpes vulpes

• †Washakius
  • †Washakius insignis
  • †Washakius izetti
• †Wickia
  • †Wickia brevirhinus – or unidentified comparable form
• †Wilsoneumys
  • †Wilsoneumys planidens

• 

  †Woodwardia
  • †Woodwardia arctica
  • †Woodwardia gravida
  • †Woodwardia preareolata
• †Worlandia
  • †Worlandia inusitata – type locality for species
• †Wrightohyus
  • †Wrightohyus yatkolai
• †Wyolestes
  • †Wyolestes apheles
  • †Wyolestes dioctes – type locality for species
• †Wyomomys
  • †Wyomomys bridgeri – type locality for species
• †Wyomylus – type locality for genus
  • †Wyomylus whitei – type locality for species
• †Wyonycteris – type locality for genus
  • †Wyonycteris chalix – type locality for species

• †Xanclomys
  • †Xanclomys mcgrewi – type locality for species
• †Xenicohippus
  • †Xenicohippus craspedotum
  • †Xenicohippus grangeri
• †Xenochelys
  • †Xenochelys bridgerensis – type locality for species
  • †Xenochelys formosa
  • †Xenochelys lostcabinensis – type locality for species
• †Xenocranium
• †Xestops
  • †Xestops gracilis – type locality for species
  • †Xestops lentus – type locality for species
  • †Xestops microdus – type locality for species
  • †Xestops minutus – type locality for species
  • †Xestops piercei – type locality for species
  • †Xestops savagei – type locality for species
  • †Xestops vagans – type locality for species
  • †Xestops vagrans
• †Xyronomys
  • †Xyronomys swainae – type locality for species

• †Yoderimys – type locality for genus
  • †Yoderimys bumpi – type locality for species
  • †Yoderimys stewarti

• 

  †Ysengrinia
  • †Ysengrinia americana

• †Zamia
  • †Zamia coloradensis
  • †Zamia colorodensis
  • †Zamia wyomingensis
• †Zangerlichelys
  • †Zangerlichelys aequa
• †Zanycteris
  • †Zanycteris paleocenus
• Zelkova
  • †Zelkova nervosa
• †Zemiodontomys
  • †Zemiodontomys burkei
• Zenaida
  • †Zenaida rnacroura
• †Ziamys – or unidentified comparable form
• †Zingiberopsis
  • †Zingiberopsis isonervosa
• Zizyphus
  • †Zizyphus serrulatus
• †Zodiolestes
• Zonotrichia

  • 

    †Zonotrichia albicollis

• Various Contributors to the Paleobiology Database. "Fossilworks: Gateway to the Paleobiology Database". Retrieved 17 December 2021.