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

A

• †Abra – tentative report
  • †Abra longicalla
• Acanthodesia
  • †Acanthodesia oblongula
  • †Acanthodesia savartii
• †Acantodesia
  • †Acantodesia oblongula
• 

  Illustration of a living Acipenser sturgeon
  Acipenser
• †Acrocoelum
  • †Acrocoelum richardsi – type locality for species
• Acropora
  • †Acropora palmata
• Acteocina
  • †Acteocina canaliculata
• Acteon
  • †Acteon danicus – type locality for species
  • †Acteon ovoides
• †Adocus
• †Aepycamelus – tentative report
• Aetobatus
  • †Aetobatus arcuatus
  • †Aetobatus irregularis
  • †Aetobatus profundus – type locality for species
• 

  Fossilized skull of the Miocene baleen whale Aglaocetus
  †Aglaocetus
  • †Aglaocetus patulus
• Alca
  • †Alca torda – or unidentified comparable form
• Aligena
  • †Aligena aequata
  • †Aligena elevata
• †Ambystoma
  • †Ambystoma maculatum
  • †Ambystoma tigrinum
• Amia
• 

  Life restoration of the Miocene-Pliocene beardog Amphicyon
  †Amphicyon
• Amyda
  • †Amyda cellulosa
• Anachis
  • †Anachis avara
• Anadara
  • †Anadara andrewsi
  • †Anadara ovalis
  • †Anadara subrostrata
  • †Anadara transversa
• Anas
  • †Anas crecca
• Ancilla – report made of unidentified related form or using admittedly obsolete nomenclature
• Angulus
  • †Angulus agilis
• Anomia
  • †Anomia aculeata
  • †Anomia marylandica
  • †Anomia multilineata
  • †Anomia simplex
• Anticlimax – tentative report
  • †Anticlimax gardnerae – type locality for species
• †Aphelops – tentative report
• †Aporrhaid
  • †Aporrhaid gastropod
• Aporrhais
  • †Aporrhais potomacensis
• Aquila
  • †Aquila chrysaetos
• †Araeodelphis – type locality for genus
  • †Araeodelphis natator – type locality for species
• †Araloselachus
  • †Araloselachus cuspidata
• Arca
  • †Arca callipleura
  • †Arca improcera
• †Archaeohippus
• Architectonica
  • †Architectonica form A informal
  • †Architectonica form B informal
• 

  Restoration of an Arctodus, or short-faced bear, with a human to scale
  †Arctodus
  • †Arctodus pristinus
• Argopecten
  • †Argopecten irradians
• †Armatobalanus
  • †Armatobalanus calvertensis
• Arossia
  • †Arossia bohaska – type locality for species
  • †Arossia cummembrana – type locality for species
  • †Arossia newmani
• †Asaphis
  • †Asaphis centenaria
• †Aspideretoides
  • †Aspideretoides virginianus
• 

  Shell of a modern Astarte bivalve
  Astarte
  • †Astarte cuneiformis
  • †Astarte exaltata
  • †Astarte marylandica
  • †Astarte obruta
  • †Astarte perplana
  • †Astarte thisphila
  • †Astarte thomasi
  • †Astarte undata
• Asterias
  • †Asterias forbesi – or unidentified comparable form
• Astrangia
  • †Astrangia danae
• †Astrehelia
  • †Astrehelia palmata
• †Astrhelia
  • †Astrhelia plamata
• †Astroscopus
  • 

    Life restoration of the Miocene stargazer Astroscopus countermani
    †Astroscopus countermani – type locality for species
• Astyris
  • †Astyris communis
  • †Astyris lunata
• Ataphrus
  • †Ataphrus glandula
• Athleta
  • †Athleta limopsis
  • †Athleta tuomeyi
• †Atopomys
  • †Atopomys texensis
• Atrina
  • †Atrina harrisi
  • †Atrina harrisii
• 

  Life restoration of the Miocene sperm whale Aulophyseter
  †Aulophyseter
  • †Aulophyseter mediatlanticus – type locality for species

B

• 

  Portrait of a living Balaenoptera baleen whale
  Balaenoptera
  • †Balaenoptera cephalus
  • †Balaenoptera pusilla – type locality for species
• Balanus
  • †Balanus concabvus
  • †Balanus concava
  • †Balanus crenatus
  • †Balanus imitator
  • †Balanus vulcanellus – type locality for species
• Bankia
  • †Bankia gouldi
• Barnea
  • †Barnea costata
• Bathytormus
  • †Bathytormus alaeformis
• †Batiacasphaera
  • †Batiacasphaera sphaerica
• †Belosphys
• Bicorbula
  • †Bicorbula idonea
• Blarina
  • 

    A living Blarina brevicauda, or northern short-tailed shrew
    †Blarina brevicauda
  • †Blarina carolinensis
• †Bolis – or unidentified comparable form
• Bonasa
  • †Bonasa umbellus
• Boreotrophon
  • †Boreotrophon harasewychi – type locality for species
• Brachidontes
  • †Brachidontes potomacensis
• †Brachyprotoma
  • †Brachyprotoma obtusata
• †Brevirostrodelphis
  • †Brevirostrodelphis dividum – type locality for species
• †Brevoortia
  • 

    A living Brevoortia tyrannus, or Atlantic menhaden
    †Brevoortia tyrannus – or unidentified comparable form
• Buccinofusus
  • †Buccinofusus chesapeakensis
  • †Buccinofusus parilis
• Bufo
  • †Bufo americanus
  • †Bufo woodhousei
• †Bulliopsis
  • †Bulliopsis marylandica
  • †Bulliopsis quadrata
• Busycon – type locality for genus
  • †Busycon carica
  • †Busycon fusiforme
  • †Busycon fusiformis
• †Busycotyphus
  • †Busycotyphus coronatum
  • †Busycotyphus rugosum
• Busycotypus
  • †Busycotypus alveatum
  • †Busycotypus asheri – type locality for species
  • †Busycotypus canaliculatus
  • †Busycotypus coronatum
  • †Busycotypus rugosum

C

• Cadulus
  • †Cadulus bellulus
  • †Cadulus newtonensis
  • †Cadulus thallus
• Caecum
  • †Caecum patuxentium
• †Calianassa
  • †Calianassa atlantica
  • †Calianassa matsoni – or unidentified comparable form
• Callinectes
  • †Callinectes ornatus
  • 

    A living Callinectes sapidus, or Chesapeake blue crab
    †Callinectes sapidus
• Calliostoma
  • †Calliostoma alphelium
  • †Calliostoma aphelium
  • †Calliostoma humile – or unidentified comparable form
  • †Calliostoma philanthropus
  • †Calliostoma philathropus
• Callista
  • †Callista marylandica
• Callocardia
  • †Callocardia catharia
• 

  A living Calonectris shearwater
  Calonectris
• Calyptraea
  • †Calyptraea aldrichi – type locality for species
  • †Calyptraea centralis
• †Calyptraphorus
  • †Calyptraphorus jacksoni
• Cancellaria
  • †Cancellaria alternata
• Cancer
  • †Cancer irroratus
• Canis
  • 

    Illustration in multiple views of a fossilized skull of the Pleistocene Canis armbrusteri, or Armbruster's wolf
    †Canis armbrusteri – type locality for species
  • †Canis latrans
  • †Canis rufus – or unidentified comparable form
• Cantharus
  • †Cantharus marylandicus
• †Carassatellites
  • †Carassatellites turgidulus
• Carcharhinus
  • †Carcharhinus egertoni
• Carcharias
  • †Carcharias collata – type locality for species
• Carcharodon
  • †Carcharodon auriculatus
  • 

    Fossilized tooth of the Miocene-Pliocene shark Cosmopolitodus hastalis, or broad-toothed mako
    †Carcharodon hastalis
• Cardita
  • †Cardita protracta
• †Caricella
• Carphophis
  • †Carphophis amoenus
• Caryocorbula
  • †Caryocorbula cuneata
  • †Caryocorbula inaqualis
• Cassis
• Castor
  • †Castor canadensis
• Catapleura
  • †Catapleura repanda – type locality for species
• †Cephalotropis – type locality for genus
  • †Cephalotropis coronatus – type locality for species
• Cerastoderma
  • †Cerastoderma leptopleurum
• Cervus
• †Cetophis – type locality for genus
  • †Cetophis heteroclitus – type locality for species
• Cetorhinus
• 

  Life restoration of the Miocene-Pliocene whale Cetotherium
  †Cetotherium
  • †Cetotherium megalophysum
  • †Cetotherium parvum – type locality for species
• Chama
  • †Chama corticosa
• Chelone
• Chelydra
  • †Chelydra serpentina
• †Chesacardium
  • †Chesacardium craticuloides
  • †Chesacardium laqueatum
• †Chesaclava – type locality for genus
  • †Chesaclava dissimilis
  • †Chesaclava quarlesi – type locality for species
• †Chesaconavus
  • †Chesaconavus chesapeakensis
  • †Chesaconavus rossi
• †Chesaconcavus
  • †Chesaconcavus chesapeakensis
  • †Chesaconcavus myosulcatus
  • †Chesaconcavus proteus
  • †Chesaconcavus rossi
  • †Chesaconcavus santamaria
• †Chesapecten
  • †Chesapecten coccymelus
  • †Chesapecten coccymeus
  • †Chesapecten covepointensis
  • 

    Shells of the Pliocene scallop Chesapecten jeffersonius
    †Chesapecten jeffersonius
  • †Chesapecten madisonius
  • †Chesapecten monicae
  • †Chesapecten nefrens
  • †Chesapecten santamaria
• †Chesasyrinx – type locality for genus
  • †Chesasyrinx rotifera
• †Chesatrophon – type locality for genus
  • †Chesatrophon chesapeakeanus – type locality for species
• Chlamys
  • †Chlamys choctavensis
  • †Chlamys sheldonae
• †Chloridella
  • †Chloridella empusa
• Chrysemys
  • 

    A living Chrysemys picta, or painted turtle
    †Chrysemys picta
• †Cimomia
  • †Cimomia marylandensis – type locality for species
• Circulus – report made of unidentified related form or using admittedly obsolete nomenclature
  • †Circulus form A informal
• Cirsotrema
  • †Cirsotrema form A informal
  • †Cirsotrema from B informal
• Clavus
• †Cleistophaeridium
  • †Cleistophaeridium placacanthum
• Clementia
  • †Clementia inoceriformis
• Clethrionomys
  • †Clethrionomys gapperi – or unidentified comparable form
• Cliona
  • †Cliona sulphurea
• †Clionia
  • †Clionia sulphurea
• Coluber
  • †Coluber constrictor
• 

  Fossil of the Miocene-Pleistocene barnacle Concavus
  Concavus
  • †Concavus concavus
  • †Concavus crassostricola
• Condylura
  • †Condylura cristata
• Conopeum
  • †Conopeum germanum
• Conus
  • †Conus deluvianus
  • †Conus diluvianus
  • †Conus sanctaemariae – type locality for species
• Coralliophaga
  • †Coralliophaga bryani
• 

  Shell of a Corbula basket clam
  Corbula
  • †Corbula elevata
  • †Corbula inaequalis
  • †Corbula pectorosa – type locality for species
• †Coronia
• Crassatella
  • †Crassatella aquiana
  • †Crassatella marylandica
  • †Crassatella melinus
• Crassostrea
  • †Crassostrea virginica
• Crenilabium – or unidentified comparable form
  • †Crenilabium elatum
• †Creonella
  • †Creonella obscuriplica – type locality for species
• Crepidula
  • †Crepidula fornicata
  • †Crepidula plana
• 

  Fossil of the Early Cretaceous-Eocene shark Cretolamna
  †Cretolamna
  • †Cretolamna appendiculata
• Crotalus
  • †Crotalus horridus
• Crucibulum
  • †Crucibulum constrictum
  • †Crucibulum costata
  • †Crucibulum multilineatum
• 

  A living Cryptobranchus alleganiensis, or hellbender salamander
  Cryptobranchus
  • †Cryptobranchus guildayi – type locality for species
• Cucullaea
  • †Cucullaea gigantea
  • †Cucullaea transversa
• Cumingia
  • †Cumingia tellinoides
• †Cybium
• Cyclocardia
  • †Cyclocardia granulata
• †Cyclopsiella
  • †Cyclopsiella lusatica
• Cyclostremiscus
  • †Cyclostremiscus sohli – type locality for species
• Cylichna
  • †Cylichna venusta – type locality for species
• Cymatosyrinx
  • †Cymatosyrinx mariana – type locality for species
• †Cynarctus
  • †Cynarctus marylandica – type locality for species
  • †Cynarctus wangi – type locality for species
• †Cynorca – tentative report
• Cypraea
• Cyrtopleura
  • 

    Shell in multiple views of a Cyrtopleura costata, or angel wing clam
    †Cyrtopleura costata
• Cythara
• †Cythereis
  • †Cythereis tuberculata
• Cytheridea
  • †Cytheridea punctillata
• †Cytheris
  • †Cytheris tuberculata

D

• †Dallarca
  • †Dallarca elevata
  • †Dallarca elnia
  • †Dallarca idonea
  • †Dallarca staminea
  • †Dallarca subrostrata
• 

  A living Dasyatis stingray
  Dasyatis
  • †Dasyatis centrourus – or unidentified comparable form
• †Delphinodon
  • †Delphinodon leidyi
• Dentalium
  • †Dentalium attenuatum
• †Desmathyus
• Diadophis
  • †Diadophis punctatus
• Diodora
  • †Diodora griscomi
  • †Diodora marlboroensis
  • †Diodora marylandica
  • †Diodora marylandicus
  • †Diodora nassula
  • †Diodora redimicula
• 

  Underside of the reconstructed cranium of the Miocene baleen whale Diorocetus
  †Diorocetus – type locality for genus
  • †Diorocetus hiatus – type locality for species
• Diplodonta
  • †Diplodonta marlboroensis
  • †Diplodonta subvexa
• †Dipoides
• Discinisca
  • †Discinisca lugubris
  • †Discinisca lugubrius
• Divalinga
  • †Divalinga quadrisulcata
• †Dolicholatirus
• 

  Fossil shell of the Cretaceous-modern marine venus clam Dosinia
  Dosinia
  • †Dosinia acetabulum
• †Dosiniopsis
  • †Dosiniopsis lenticularis

E

• †Eburneopecten
  • †Eburneopecten cerinus – type locality for species
  • †Eburneopecten dalli
• Echinocardium
  • †Echinocardium marylandiense – type locality for species
• Echinophoria – type locality for genus
  • †Echinophoria caelatura
• †Ecphora
  • †Ecphora chesapeakensis – type locality for species
  • 

    Illustration of a fossilized shell of the Miocene murex sea snail Ecphora gardnerae
    †Ecphora gardnerae
  • †Ecphora meganae
  • †Ecphora quadricostata
  • †Ecphora scientistensis
  • †Ecphora tampaensis
  • †Ecphora tricostata
  • †Ecphora turneri
• †Ectoganus
  • †Ectoganus gliriformis – or unidentified comparable form
• †Ectopistes
  • †Ectopistes migratorius
• Elaphe
  • †Elaphe vulpina
• Electra
  • †Electra monostachys
• Elphidium
  • †Elphidium discoidale
  • †Elphidium incertum
  • †Elphidium latispatium
• Ensis
  • †Ensis directus
  • †Ensis ensiformis
• †Entobia
• Entosolenia
  • †Entosolenia globosa
  • †Entosolenia lucida
• Eontia
  • †Eontia palmerae
  • †Eontia ponderosa
• †Eopleurotoma – or unidentified comparable form
  • †Eopleurotoma harrisi
  • †Eopleurotoma potomacensis
• 

  Fossilized cranium in multiple views of the Paleocene-Eocene gavial relative Eosuchus
  †Eosuchus
  • †Eosuchus minor
• †Eosurcula – or unidentified comparable form
  • †Eosurcula ducateli
• Epitonium
  • †Epitonium angulatum
  • †Epitonium chancellorensis – type locality for species
  • †Epitonium denticulatum
  • †Epitonium humphreysii
  • †Epitonium multistriatum
  • †Epitonium rupicola
  • †Epitonium sayanum
• Eponides
  • †Eponides frigida
• Eptesicus
  • †Eptesicus fuscus – or unidentified comparable form
• Equus
  • †Equus complicatus
  • †Equus giganteus
• Erethizon
  • †Erethizon dorsatum
• 

  Life restoration of the Pleistocene bovid Euceratherium, or the shrub ox. Robert Bruce Horsfall (1913).
  †Euceratherium
  • †Euceratherium collinum
• †Euclastes – tentative report
• Eucrassatella
  • †Eucrassatella melinus
• Eulima
  • †Eulima brightseatensis – type locality for species
  • †Eulima form A informal
• Eumeces
  • †Eumeces fasciatus – or unidentified comparable form
• Eupleura
  • †Eupleura caudata
• 

  Life restoration of the Miocene whale Eurhinodelphis (above)
  †Eurhinodelphis
  • †Eurhinodelphis longirostris
• Euspira
  • †Euspira heros
  • †Euspira marylandica
  • †Euspira tuomeyi

F

• Felis
  • †Felis couguar
• †Ficopsis
• Fissurella
  • †Fissurella fluviamariana – type locality for species
• 

  Living Fistulobalanus barnacles
  †Fistulobalanus
  • †Fistulobalanus klemmi
• †Florilus
  • †Florilus chesapeakensis
• †Florimetis
  • †Florimetis biplicata
• †Fulgar
  • †Fulgar coronatum

G

• 

  A living Galeocerdo cuvier, or tiger shark
  Galeocerdo
  • †Galeocerdo aduncus
  • †Galeocerdo appendiculatus
  • †Galeocerdo contortus
  • †Galeocerdo latidens
• Galeodea
• Gari
  • †Gari gubernatoria
• Gastrochaena
• Gavia
  • †Gavia immer
• 

  Fossilized skull of the Miocene crocodile relative Gavialosuchus
  †Gavialosuchus
  • †Gavialosuchus antiquus
• Gegania
  • †Gegania marylandica
• Gemma
  • †Gemma gemma
• Genota – or unidentified comparable form
  • †Genota bellistriata
• Geukensia
  • †Geukensia demissa
• Gibbula – tentative report
  • †Gibbula glandula
• †Gilbertina
  • †Gilbertina texana
• 

  A living Glaucomys, or New World flying squirrel
  Glaucomys
• Globigerina
  • †Globigerina praebulloides
• Globigerinoides
  • †Globigerinoides altiaperturus
  • †Globigerinoides sicanus
• †Globoquadrina
  • †Globoquadrina altispira
• Glossus
  • †Glossus fraterna
  • †Glossus ignolea – or unidentified comparable form
  • †Glossus markoei
  • †Glossus markoii
  • †Glossus marylandica
  • †Glossus mazlea
  • †Glossus santamaria
• Glycimeris
  • †Glycimeris parilis
• Glycymeris
  • †Glycymeris americana
  • †Glycymeris idonea
  • †Glycymeris lentiformis
  • †Glycymeris parilis
• Glyptemys
  • †Glyptemys muhlenbergii
• 

  Mounted fossilized skeleton of the Miocene-Pleistocene elephant relative Gomphotherium
  †Gomphotherium
  • †Gomphotherium obscurum – type locality for species
• †Gryphaeostrea
  • †Gryphaeostrea vomer
• Gulo
  • †Gulo gulo
• Gyrinophilus
  • †Gyrinophilus porphyriticus – or unidentified comparable form

H

• †Habibacysta
  • †Habibacysta tectata
• †Hadrodelphis – type locality for genus
  • †Hadrodelphis calvertense – type locality for species
• †Halicetus – type locality for genus
  • †Halicetus ignotus – type locality for species
• Haminoea
  • †Haminoea solitaria
• 

  Shells in differing orientations of Hastula augur sea snails
  Hastula
  • †Hastula inornata
  • †Hastula simplex
• Haustator
  • †Haustator form A informal
  • †Haustator gnoma – type locality for species
  • †Haustator premortoni – type locality for species
• †Heliadornis – type locality for genus
  • †Heliadornis ashbyi – type locality for species
• Hemimactra
  • †Hemimactra solidissima
  • †Hemimactra subparilis
• Hemipristis
  • 

    Fossilized teeth of the Miocene weasel shark Hemipristis serra
    †Hemipristis serra
• †Hercoglossa
  • †Hercoglossa tuomeyi – type locality for species
• †Hesperhys
• Heterodon
  • †Heterodon platyrhinos – or unidentified comparable form
• Hiatella
  • †Hiatella arctica
  • †Hiatella artica
• Hippoporidra
  • †Hippoporidra edax
• 

  Mounted fossilized skeleton of the Miocene-Pliocene horse Hippotherium
  †Hippotherium
• Hyla
  • †Hyla crucifer
• Hyotissa
  • †Hyotissa haitensis
• Hysteroconcha
  • †Hysteroconcha marylandica
  • †Hysteroconcha staminaea
• †Hystrichosphaeropsis
  • †Hystrichosphaeropsis obscura

I

• Ictalurus
• Ilyanassa
  • †Ilyanassa obsoleta
  • †Ilyanassa trivittata
• Ischadium
  • †Ischadium recurvum
• 

  Fossilized skeleton of the Middle Jurassic-Miocene Chimaera relative Ischyodus
  †Ischyodus
  • †Ischyodus williamsae – type locality for species
• Isognomon
  • †Isognomon maxillata
  • †Isognomon tortum
• Isurus
• †Ixacanthus – type locality for genus
  • †Ixacanthus coelospondylus – type locality for species

J

• †Judithemys
  • †Judithemys kranzi – type locality for species

K

• Kalolophus
  • †Kalolophus antillarum
• †Kapalmerella
  • †Kapalmerella mortoni
• 

  Life restoration of the Oligocene-Miocene dolphin Kentriodon
  †Kentriodon – type locality for genus
  • †Kentriodon pernix – type locality for species
• †Kummelia
  • †Kummelia americana
• Kuphus – report made of unidentified related form or using admittedly obsolete nomenclature
• Kurtziella
  • †Kurtziella cerina

L

• †Labyrinthodinium
  • †Labyrinthodinium truncatum
• †Lacinia
  • †Lacinia pygmaea – type locality for species
• Lacuna
  • †Lacuna feorra – type locality for species
• †Laevihastula – type locality for genus
  • †Laevihastula marylandica – type locality for species
  • †Laevihastula simplex
• †Lagodon
• 

  A modern Lamna mackerel shark
  Lamna
  • †Lamna denticulata
  • †Lamna obliqua
  • †Lamna vincenti
• Lampropeltis
  • †Lampropeltis triangulum
• Lasiopodomys
  • †Lasiopodomys deceitensis
• Lenticulina
  • †Lenticulina rotulata
• Lepisosteus
• †Leptomactra
  • †Leptomactra delumbis
  • †Leptomactra marylandica
• †Leptophoca – type locality for genus
  • †Leptophoca lenis – type locality for species
  • †Leptophoca proxima – or unidentified comparable form
• Lepus
  • 

    A living Lepus americanus, or snowshoe hare
    †Lepus americanus
• †Levifusus
  • †Levifusus trabeatus
• Libinia
  • †Libinia dubia
• †Lingulodinium
  • †Lingulodinium macherophorum
• Lirophora
  • †Lirophora alevata
  • †Lirophora alveata
  • †Lirophora latilirata
  • †Lirophora parkeria
• Lithophaga – or unidentified comparable form
  • †Lithophaga marylandica
• Littoraria
  • †Littoraria irrorata
• Lontra
  • 

    Pair of living Lontra canadensis, or North American river otter
    †Lontra canadensis
• †Lophocetus
  • †Lophocetus calvertensis – type locality for species
  • †Lophocetus pappus – type locality for species
• †Lophochelys – tentative report
• Lopholatilus
• Loxoconcha
  • †Loxoconcha impressa
• Lucina – report made of unidentified related form or using admittedly obsolete nomenclature
• Lucina
  • †Lucina dartoni
  • †Lucina whitei
• Lucinoma
  • †Lucinoma contracta
  • †Lucinoma filosa
• Lunatia
  • †Lunatia catenoides
• Lyonsia
  • †Lyonsia hyalina

M

• Macoma
  • 

    Shell of a Limecola balthica, or Baltic clam
    †Macoma balthica
  • †Macoma calcarea
• Macrocallista
  • †Macrocallista marylandica
  • †Macrocallista subimpressa
• †Macrokentriodon – type locality for genus
  • †Macrokentriodon morani – type locality for species
• Mactrodesma
  • †Mactrodesma subponderosa
  • †Mactrodesma subponderosum
• †Mammut
  • †Mammut americanum
• †Mammuthus
  • †Mammuthus columbi
  • 

    Life restorations of a Mammut americanum, or American mastodon (right), and a Mammuthus primigenius, or wooly mammoth (left)
    †Mammuthus primigenius
• Marginella
  • †Marginella minuta
• †Mariacolpus – type locality for genus
  • †Mariacolpus plebeia
• †Mariadrillia – type locality for genus
  • †Mariadrillia parvoidea
• †Mariafusus – type locality for genus
  • †Mariafusus marylandica
• †Marianarona – type locality for genus
  • †Marianarona asheri – type locality for species
  • †Marianarona marylandica – type locality for species
• †Mariasalpinx – type locality for genus
  • †Mariasalpinx emilyae – type locality for species
• †Mariasveltia – type locality for genus
  • †Mariasveltia lunata
• †Mariaturricula – type locality for genus
  • †Mariaturricula biscatenaria
• Marmota
  • 

    A living Marmota monax, or groundhog
    †Marmota monax
• Martesia
  • †Martesia cuneiformis
  • †Martesia ovalis
• †Marvacrassatella
  • †Marvacrassatella marylandica
  • †Marvacrassatella melina
  • †Marvacrassatella turgidula
• Massilina
  • †Massilina marylandica
• Mathilda
  • †Mathilda crebricosta – type locality for species
  • †Mathilda form A informal
  • †Mathilda form B informal
  • †Mathilda form C informal
  • †Mathilda kauffmani – type locality for species
  • †Mathilda marylandensis – type locality for species
• †Medoriopsis
  • †Medoriopsis marylandica
• 

  Mounted fossilized skeleton of the Miocene-Pleistocene ground sloth Megalonyx
  †Megalonyx
• Megaptera
  • †Megaptera expansa – type locality for species
• Melampus
  • †Melampus bidentatus
• Melanitta
  • †Melanitta deglandi
• Meleagris
  • †Meleagris gallopavo
• †Melosia
  • †Melosia staminea
• Membranipora
  • †Membranipora flabellata
• Menestho
  • †Menestho form A informal
• Mephitis
  • †Mephitis mephitis
• Mercenaria
  • †Mercenaria blakei
  • †Mercenaria campechiensis
  • †Mercenaria cuneata – type locality for species
  • †Mercenaria ducatelli – tentative report
  • 

    Collection of Mercenaria mercenaria, also known as hard clams or quahogs
    †Mercenaria mercenaria
  • †Mercenaria plena
  • †Mercenaria staminea
  • †Mercenaria subcuneata
  • †Mercenaria tetrica
• Meretrix
  • †Meretrix subimpressa
• †Merychippus
• †Mesocetus
  • †Mesocetus siphunculus
• †Mesorhytis – tentative report
  • †Mesorhytis pomonkensis
  • †Mesorhytis potomacensis
• †Messapicetus
  • †Messapicetus longirostris
• 

  Mounted fossilized skeleton of the Miocene-Pleistocene manatee relative Metaxytherium
  †Metaxytherium
  • †Metaxytherium crataegense – type locality for species
• †Micropogon
  • †Micropogon undulatus
• Microtus
  • †Microtus chrotorrhinus – or unidentified comparable form
  • †Microtus guildayi
  • †Microtus involutus – or unidentified comparable form
  • †Microtus pennsylvanicus
• Mictomys
  • †Mictomys borealis
• Miltha
  • †Miltha aquiana
• †Miocepphus
  • †Miocepphus bohaskai – type locality for species
  • †Miocepphus mcclungi
• 

  Restoration of the Pliocene-Pleistocene Miracinonyx, or American cheetah
  †Miracinonyx
  • †Miracinonyx inexpectatus
• Mitra
  • †Mitra marylandica
• Modiolus
  • †Modiolus dalli
  • †Modiolus ducatelli
  • †Modiolus ducatellii
  • †Modiolus modiolus
  • †Modiolus potomacensis – type locality for species
• †Moira – tentative report
  • †Moira atropos
• †Monotherium
  • †Monotherium affine
• Morus
  • †Morus avitus – type locality for species
• Mulinia
  • †Mulinia lateralis
• Mustela
  • 

    A living Neovison vison, or American mink
    †Mustela vison – or unidentified comparable form
• †Mya
  • †Mya arenaria
• Myliobatis
  • †Myliobatis dixoni – type locality for species
  • †Myliobatis frangens – type locality for species
  • †Myliobatis fremenvillii – or unidentified comparable form
  • †Myliobatis gigas
  • †Myliobatis pachyodon
  • †Myliobatis vicomicanus
• 

  Fossilized skeleton of the Pliocene-Holocene peccary Mylohyus
  †Mylohyus
  • †Mylohyus fossilis – type locality for species
  • †Mylohyus obtusidens
• Myotis
  • †Myotis grisescens – or unidentified comparable form
• Myrtea – tentative report
  • †Myrtea astartiformis
  • †Myrtea uhleri
• Mysella
  • †Mysella planulata
• Mytilus
  • †Mytilus incurvus

N

• †Nanosiren – tentative report
• Napaeozapus
  • †Napaeozapus insignis
• Narona
  • †Narona potomacensis
• Nassa
• 

  A living Nassarius, or nassa mud snail
  Nassarius
  • †Nassarius peralta
  • †Nassarius vibex
• Nemocardium
  • †Nemocardium lene
• Neofiber
• Neotoma – type locality for genus
  • †Neotoma floridana
  • †Neotoma spelaea – type locality for species
• Nerodia
  • 

    A living Nerodia sipedon, or northern water snake
    †Nerodia sipedon
• Neverita
  • †Neverita asheri – type locality for species
  • †Neverita cliftonensis
  • †Neverita discula – type locality for species
  • †Neverita duplicatus
  • †Neverita potomacensis – type locality for species
• †Nodisurculina – type locality for genus
  • †Nodisurculina engonata
• Noetia
  • †Noetia carolinensis
• Nonion
  • †Nonion calvertensis
  • †Nonion pompilioides
  • †Nonion sloanii
• Notidanus
  • †Notidanus primigeneus
  • †Notidanus primigenius
• Notophthalmus
  • †Notophthalmus viridescens – or unidentified comparable form
• Notorynchus
  • 

    Close-up portrait of a living Notorynchus cepedianus, or broadnose sevengill shark
    †Notorynchus cepedianus – type locality for species
• Novocrania
  • †Novocrania lububris
• Nucula
  • †Nucula potomacensis
  • †Nucula proxima
  • †Nucula prunicola
  • †Nucula taphria
• Nuculana
  • †Nuculana acuta
  • †Nuculana cliftonensis
  • †Nuculana cultelliformis
  • †Nuculana improcera
  • †Nuculana liciata
  • †Nuculana luciata
  • †Nuculana parilis
  • †Nuculana tysoni

O

• Ochotona
  • †Ochotona princeps – or unidentified comparable form
• Odocoileus
  • †Odocoileus virginianus
• 

  A living Odontaspis sand shark
  Odontaspis
  • †Odontaspis actutissima
  • †Odontaspis acutissima
  • †Odontaspis hopei
  • †Odontaspis littoralis
  • †Odontaspis macrota
  • †Odontaspis verticalis
  • †Odontaspis winkleri
• †Odontopolys
• Odostomia
  • †Odostomia insignifica
• †Ogivalina
  • †Ogivalina parvula
• Ondatra
  • †Ondatra annectens
  • †Ondatra zibethicus
• †Operculodinium
  • †Operculodinium centrocarpum
  • †Operculodinium piaseckii
• Opheodrys
  • †Opheodrys vernalis
• Ophiura
  • †Ophiura marylandica
• 

  Life restoration of the Miocene sperm whale Orycterocetus
  †Orycterocetus
  • †Orycterocetus crocodilinus
• †Osteopygis
  • †Osteopygis roundsi
• Ostrea
  • †Ostrea alepidota
  • †Ostrea carolinensis
  • †Ostrea trachydiscus – type locality for species
• †Otodus
  • †Otodus angustidens – tentative report
  • 

    Diagram illustrating the largest (grey) and most conservative (red) size estimates of the Miocene-Pliocene shark Carcharocles megalodon (sometimes Carcharodon or Otodus megalodon) with a whale shark (violet), great white shark (green), and anachronistic human (black) to scale
    †Otodus megalodon
• Otus
  • †Otus guildayi – type locality for species
• †Oxyrhina
  • †Oxyrhina cuspidata
  • †Oxyrhina desorii
  • †Oxyrhina elegans
  • †Oxyrhina retroflexa
  • †Oxyrhina sillimani

P

• Pagurus
  • †Pagurus pollicaris
• †Palaeocarcharodon
  • †Palaeocarcharodon orientalis
• †Palaeocystodinium
  • †Palaeocystodinium golzowense
• 

  Restoration of the Cretaceous-Eocene sea snake Palaeophis
  †Palaeophis
  • †Palaeophis grandis
• †Pamicellaria
  • †Pamicellaria convoluta
• Pandora
  • †Pandora gouldiana
• Panopea
  • †Panopea americana
  • †Panopea elongata
  • †Panopea goldfussi
  • †Panopea goldfussii
  • †Panopea whitfieldi
• Panopeus
  • †Panopeus herbstii
• Panthera
  • 

    A living Panthera leo, or lion
    †Panthera leo
  • †Panthera onca
• Paraconcavus
  • †Paraconcavus rooseveltensis
• †Paramya
  • †Paramya subovata
• Parascalops
  • †Parascalops breweri
• †Parietobalaena – type locality for genus
  • †Parietobalaena palmeri – type locality for species
• Parvilucina
  • †Parvilucina crenulata
  • †Parvilucina multistriata
• †Pasitheola
  • †Pasitheola marylandensis – type locality for species
• Pecten
  • †Pecten humphreysii
  • †Pecten marylandica
• Pekania
  • †Pekania diluviana – type locality for species
• †Pelocetus – type locality for genus
  • †Pelocetus calvertensis – type locality for species
• †Pelodelphis – type locality for genus
  • †Pelodelphis gracilis – type locality for species
• †Pentadinium
  • †Pentadinium latincinctum – or unidentified comparable form
• Periploma – tentative report
• Perisoreus
  • 

    A living Perisoreus canadensis, or grey jay
    †Perisoreus canadensis
• Peromyscus
  • †Peromyscus cumberlandensis
  • †Peromyscus leucopus – or unidentified comparable form
• †Petauristodon
  • †Petauristodon alpinus – or unidentified comparable form
• Petricola
  • †Petricola calvertensis
  • †Petricola pholadiformis
• Phacoides
  • †Phacoides anodonata
  • †Phacoides contractus
• 

  Life restoration of the Paleocene-Eocene ungulate Phenacodus. Charles R. Knight (1898).
  †Phenacodus – tentative report
• †Phenacomya
  • †Phenacomya petrosa
• Phenacomys
• †Phocageneus
  • †Phocageneus venustus
• Pholadomya
  • †Pholadomya marylandica
• †Physeterula
• Physodon
  • †Physodon triqueter
• Pinna
• Pipistrellus
• 

  Shell of a Pitar venus clam
  Pitar
  • †Pitar morrhuanus
  • †Pitar ovatus
  • †Pitar pyga
  • †Pitar subnasuta
• Pitymys
  • †Pitymys cumberlandensis
• Placopecten
  • †Placopecten clintonius
  • †Placopecten marylandica
  • †Placopecten virginiana
• Platidia
  • †Platidia marylandica – type locality for species
• 

  Restoration of a herd of alarmed Miocene-Pleistocene peccaries of the genus Platygonus. Charles R. Knight (1922).
  †Platygonus
  • †Platygonus cumberlandensis
  • †Platygonus intermedius – type locality for species
  • †Platygonus tetragonus
  • †Platygonus vetus
• Plecotus
  • †Plecotus alleganiensis – type locality for species
• Plethodon
  • †Plethodon gultinosus
• Pleurotomella
  • †Pleurotomella bellistriata – type locality for species
• †Pliorhytis
  • †Pliorhytis centenaria
• Pogonias
  • 

    A living Pogonias cromis, or black drum
    †Pogonias cromis – or unidentified comparable form
• †Poliniciella – type locality for genus
  • †Poliniciella marylandica – type locality for species
• Polydora
• Polystira
  • †Polystira barretti
  • †Polystira communis
• Poromya
  • †Poromya subovata
• †Praeorbulina
  • †Praeorbulina glomerosa
• 

  Life restoration of the Paleocene-Eocene waterfowl Presbyornis
  †Presbyornis
  • †Presbyornis isoni – type locality for species
• †Prionodon
  • †Prionodon egertoni
• Prionotus
  • †Prionotus evolans – or unidentified related form
• †Priscodelphinus
  • †Priscodelphinus acutidens – type locality for species
  • †Priscodelphinus atropius – type locality for species
  • †Priscodelphinus conradi
  • †Priscodelphinus stenus – type locality for species
  • †Priscodelphinus uraeus
• †Priscoficus
  • †Priscoficus arguta
• Propebela
  • †Propebela marylandica – type locality for species
  • †Propebela parva
• Prophaethon – tentative report
• †Prosthennops
  • †Prosthennops niobrarensis
  • †Prosthennops xiphodonticus
• †Protocardia
  • †Protocardia virginiana
• Pseudacris
  • 

    A living Pseudacris triseriata, or western chorus frog
    †Pseudacris triseriata
• †Pseudoaptyxis
  • †Pseudoaptyxis sanctaemariae – type locality for species
• †Pseudocepphus – type locality for genus
  • †Pseudocepphus teres – type locality for species
• Pseudoliva
  • †Pseudoliva longicostata – type locality for species
  • †Pseudoliva tuberculifera
• Pseudomalaxis – or unidentified comparable form
  • †Pseudomalaxis ripleyana
• †Pseudophorus
  • †Pseudophorus calvertensis – type locality for species
• †Pseudotrition
  • †Pseudotrition ruber
• Pteria
• †Ptychosalpinx
  • †Ptychosalpinx altilis
  • †Ptychosalpinx multirugata
  • †Ptychosalpinx pustulosus – type locality for species
• 

  A living Puffinus shearwater
  Puffinus
  • †Puffinus conradi – type locality for species
• Pycnodonte
  • †Pycnodonte percrassa
• †Pyropsis – tentative report

Q

• 

  Shell of a Quinqueloculina foraminiferan
  Quinqueloculina
  • †Quinqueloculina flexuosa
  • †Quinqueloculina seminula

R

• †Rana
  • 

    A living Lithobates clamitans (sometimes Rana clamitans), or green frog
    †Rana clamitans
  • †Rana pipiens
  • †Rana sylvatica
• Rangia
  • †Rangia cuneata
• Ranzania
• †Reticulatosphaera
  • †Reticulatosphaera actinocoronata
• Retusa
  • †Retusa conulus
  • †Retusa marylandica
  • †Retusa sylvaerupis
• †Rhabdosteus – type locality for genus
  • †Rhabdosteus latiradix – type locality for species
• Rhinoptera
• Rhynchobatus
  • †Rhynchobatus pristinus
• †Roccus
  • 

    A living Morone saxatilis (formerly Roccus saxatilis), or striped bass
    †Roccus saxatilis
• †Rotalia
  • †Rotalia beccardi
  • †Rotalia beccarii

S

• Saccella
  • †Saccella parva
• Salamandra
  • †Salamandra opaca
• †Sangamona
  • †Sangamona fugitiva
• †Scala
  • †Scala marylandica
• 

  Fossilized teeth of the Neogene sperm whale Scaldicetus
  †Scaldicetus
• †Scapanorhynchus
  • †Scapanorhynchus subulatus – tentative report
• Scaphander
  • †Scaphander potomacensis – type locality for species
• Scaphella – type locality for genus
  • †Scaphella solitaria
  • †Scaphella virginiana
• Sceloporus
  • †Sceloporus undulatus – or unidentified comparable form
• 

  Fossilized skull of the Miocene toothed whale Schizodelphis
  †Schizodelphis
  • †Schizodelphis barnesi
  • †Schizodelphis sulcatus
• Schizoporella
  • †Schizoporella unicornis
• Sciaenops
  • †Sciaenops eastmani
• Sciuropterus
  • †Sciuropterus volans
• Sciurus
  • †Sciurus carolinensis
• †Scutella
  • †Scutella aberti
• †Sediliopsis – type locality for genus
  • †Sediliopsis gracilis
• Seila
  • †Seila adamsii
• Semele – tentative report
• Semele
  • †Semele carinata
  • †Semele subovata
• Serpulorbis
  • †Serpulorbis granifera
  • †Serpulorbis graniferus
• †Sigmesalia
  • †Sigmesalia palmerae – type locality for species
• Siphonalia
  • †Siphonalia devexus
  • †Siphonalia potomacensis – type locality for species
• †Siphonocetus
  • †Siphonocetus clarkianus
  • †Siphonocetus priscus
• 

  Life restoration of the Pleistocene-Holocene saber-tooth cat Smilodon
  †Smilodon
  • †Smilodon fatalis
• †Smilodontopis
  • †Smilodontopis mooreheadi
• Solariorbis
  • †Solariorbis form A informal
  • †Solariorbis laurelae – type locality for species
  • †Solariorbis lipara
• †Solarium
  • †Solarium trilineatum
• Solecardia
  • †Solecardia cossmani
• Solen
• Sorex
  • 

    A living Sorex cinereus, or cinereus shrew
    †Sorex cinereus
  • †Sorex fumeus
• Spermophilus
  • †Spermophilus tridecemlineatus
• †Sphaerula
  • †Sphaerula subvexa
• Sphenia – tentative report
• †Sphyraenodus
  • †Sphyraenodus speciosus
• 

  A living Sphyrna hammerhead shark
  Sphyrna
  • †Sphyrna laevissima – type locality for species
  • †Sphyrna magna
  • †Sphyrna prisca
• Spilogale
  • †Spilogale putorius – type locality for species
• †Spiniferites
  • †Spiniferites mirabilis
• Spiroplectammina
  • †Spiroplectammina spinosa
• Spisula
  • †Spisula subcuneata
• 

  Life restoration of the Oligocene-Miocene shark-toothed dolphin Squalodon
  †Squalodon
  • †Squalodon atlanticus
  • †Squalodon calvertensis – type locality for species
  • †Squalodon mento – type locality for species
  • †Squalodon protervus
  • †Squalodon whitmorei
  • †Squalodon wymanii – type locality for species
• Squatina
  • †Squatina occidentalis – type locality for species
• Squilla
  • 

    Illustration of a living Squilla empusa mantis shrimp
    †Squilla empusa
• †Stenasodelphis – type locality for genus
  • †Stenasodelphis russellae – type locality for species
• Stewartia
  • †Stewartia anodonta
  • †Stewartia foremani
• Sthenorytis
  • †Sthenorytis pachypleura
• Stramonita
  • †Stramonita haemostoma
• †Strepsidura
• Strioterebrum
  • †Strioterebrum dislocatum
• Stylopoma
  • †Stylopoma spongites
• †Sumatradinium
  • †Sumatradinium druggii
• †Syllomus
  • †Syllomus aegyptiacus – type locality for species
• Sylvilagus
  • †Sylvilagus floridanus
• Synaptomys
  • 

    A living Synaptomys cooperi, or southern bog lemming
    †Synaptomys cooperi
• †Synechodus
  • †Synechodus clarki
  • †Synechodus clarkia
• Syrnola
  • †Syrnola toulmini – type locality for species

T

• Tagelus
  • †Tagelus plebeius
• Tamias
  • †Tamias striatus
• Tamiasciurus
  • †Tamiasciurus hudsonicus
• †Taphrosphys
  • †Taphrosphys miocenica – type locality for species
• †Tapiravus
  • †Tapiravus validus – or unidentified comparable form
• 

  A living Tapirus, or tapir
  Tapirus
  • †Tapirus haysii – or unidentified comparable form
• †Tasbacka
  • †Tasbacka ruhoffi – type locality for species
• Taxidea
  • †Taxidea taxus – type locality for species
• †Tectatodinium
  • †Tectatodinium pellitum
• Teinostoma
  • †Teinostoma barryi
  • †Teinostoma umbilicatum
• Tellina
  • †Tellina virginiana
  • †Tellina williamsi
• Terebra
  • †Terebra curvilirata
  • †Terebra inornata
• Terebratula
  • †Terebratula marylandica – type locality for species
• Teredo
  • †Teredo virginiana
• Terrapene
  • †Terrapene carolina
• Testudo
  • †Testudo ducateli – type locality for species
• Textularia
  • †Textularia ultimainflata
• Thamnophis
• 

  Fossilized skeleton of the Oligocene-Miocene gavial relative Thecachampsa
  †Thecachampsa
  • †Thecachampsa antiqua
  • †Thecachampsa marylandica – type locality for species
• †Thinocetus
  • †Thinocetus arthritus
• Thomomys – type locality for genus
  • †Thomomys potomacensis – type locality for species
• Thracia
  • †Thracia conradi
• Torcula
  • †Torcula variabilis
• †Tornatellaea
  • †Tornatellaea texana
• Torquesia
  • †Torquesia prehumerosa – type locality for species
• 

  A living Tremarctos, or spectacled bear
  Tremarctos
  • †Tremarctos floridanus
• †Tretosphys
  • †Tretosphys lacertosus – type locality for species
  • †Tretosphys ruschenbergeri – type locality for species
• Triloculina
  • †Triloculina rotunda
• Trionyx – report made of unidentified related form or using admittedly obsolete nomenclature
  • †Trionyx halophilus
• Triphora
  • †Triphora tricincta
• Tritonium
  • †Tritonium centrosum – type locality for species
• Trochita
  • †Trochita aperta
• †Trygon
  • †Trygon dux
• †Tuba – tentative report
• †Tuberculodinium
  • †Tuberculodinium vancampoae
• Tudicla – or unidentified comparable form
• Turricula – report made of unidentified related form or using admittedly obsolete nomenclature
• †Turrifulgur – type locality for genus
  • †Turrifulgur turriculus – type locality for species
• Turris – report made of unidentified related form or using admittedly obsolete nomenclature
  • †Turris piscatavensis
  • †Turris tysoni
• 

  Fossilized shells of the Late Jurassic-modern tower snail Turritella
  Turritella
  • †Turritella alticostata
  • †Turritella exaltata
  • †Turritella humerosa
  • †Turritella indenta
  • †Turritella indentata
  • †Turritella plebeius
  • †Turritella plebeua
  • †Turritella potomacensis
  • †Turritella subponderosa
  • †Turritella subvariabilis
  • †Turritella terebriformis
• 

  A living Tursiops, or bottlenose dolphin
  Tursiops
• Typhis
  • †Typhis acuticosta

U

• Umbraculum – tentative report
• Urosalpinx
  • †Urosalpinx cinerea
  • †Urosalpinx subrusticus
• Ursus
  • 

    A living Ursus americanus, or American black bear
    †Ursus americanus

V

• Venericardia
  • †Venericardia ascia
  • †Venericardia potapacoensis
  • †Venericardia regia
• 

  A living Vespertilio bat
  Vespertilio
  • †Vespertilio grandis
• Vitrinella
  • †Vitrinella clarkmartini – type locality for species
• Volutifusus
  • †Volutifusus acus – type locality for species
  • †Volutifusus asheri – type locality for species
  • †Volutifusus marylandicus – type locality for species
  • †Volutifusus meganucleus – type locality for species
  • †Volutifusus mutabilis
• Volvulella
• Vulpes

X

• Xestoleberis
• 

  Fossilized skeleton of the Miocene whale Xiphiacetus
  †Xiphiacetus
  • †Xiphiacetus bossi – type locality for species
  • †Xiphiacetus cristatus – type locality for species
• Xiphias
  • †Xiphias radiata – tentative report

Y

• Yoldia
  • †Yoldia laevis
  • 

    Illustration of the shell of a Yoldia limatula, or file yoldia
    †Yoldia limatula
  • †Yoldia potomacensis
• †Yolida

Z

• †Zarhachis – type locality for genus
  • †Zarhachis crassangulum – type locality for species
  • †Zarhachis flagellator – type locality for species
  • †Zarhachis tysonii – type locality for species
• †Zikkuratia
  • †Zikkuratia danica – type locality for species
• †Zizyphinus
  • †Zizyphinus bryanii – type locality for species

References

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