List of the Paleozoic life of Ohio

This list of the Paleozoic life of Ohio contains the various prehistoric life-forms whose fossilized remains have been reported from within the US state of Ohio and are between 538.8 and 252.17 million years of age.

A

 * †Abylea – type locality for genus
 * †Abylea minuta – type locality for species
 * †Acacocrinus
 * †Acacocrinus anebos
 * †Acanthatia
 * †Acanthoclema
 * †Acanthoclema lineatum
 * †Acanthoclema ohioensis
 * †Acanthoclema sulcatum
 * †Acanthonema
 * †Acanthonema holopiforme
 * †Acanthonema newberryi
 * †Acanthopecten
 * †Acanthopecten bellosum – type locality for species
 * †Acanthopecten carboniferus
 * †Acanthotriletes
 * †Acanthotriletes aculeolatus
 * †Achatella
 * †Acidaspis
 * †Acidaspis cincinnatiensis
 * †Acleistoceras – tentative report
 * †Acmaeoblatta – type locality for genus
 * †Acmaeoblatta lanceolata – type locality for species
 * †Acriora
 * †Acriora petala
 * †Acteonina
 * †Acteonina hanseni – type locality for species
 * †Actinodesma
 * †Actinodesma erectum
 * †Actinopteria
 * †Actinopteria boydi
 * †Acutichiton – type locality for genus
 * †Acutichiton pyrmidalus – type locality for species
 * †Adamanterpeton – type locality for genus
 * †Adamanterpeton ohioensis – type locality for species
 * †Aechmina
 * †Aechmina richmondensis
 * †Aethaspis
 * †Agelacrinites
 * †Agelacrinites southworthi – or unidentified comparable form
 * †Agnesia
 * †Agnesia prosseri
 * †Alaionema
 * †Alaionema crenulatum
 * †Alaskozygopleura
 * †Alaskozygopleura gracillium
 * †Alatisporites
 * †Alatisporites trialatus
 * Alethopteris PAMuseum.jpg †[[Alethopteris]]
 * †Allocryptaspis
 * †Alloiopteris
 * †Alloiopteris erosa
 * †Allonema
 * †Allonychia
 * †Allorisma
 * †Allorisma costatum
 * †Alveolites
 * †Alveolites labechii
 * †Ambedus – type locality for genus
 * †Ambedus pusilus – type locality for species
 * †Ambocoelia
 * †Ambocoelia norwoodi
 * †Ambocoelia umbonata
 * †Ambonychia
 * †Ambonychia alata
 * †Ambonychia cultrata
 * †Ambonychia richmondensis
 * †Ambonychia suberecta
 * †Ambozone
 * †Ambozone peoriensis – or unidentified comparable form
 * †Ametroblatta
 * †Ametroblatta strigosa – type locality for species
 * †Ameura
 * †Ameura missouriensis
 * †Ammonidium
 * †Ammonidium hamatum
 * †Amphilichas
 * †Amphiscapha
 * †Amphiscapha catilloides
 * †Amphiscapha reedsi
 * Amplexopora Trypanites section.jpg †[[Amplexopora]]
 * †Amplexopora pustulosa
 * †Amplexopora robusta
 * †Anaptychus – tentative report
 * †Anaptychus emersoni
 * †Anartiocystis
 * †Anartiocystis foerstei
 * †Anaspyroceras
 * †Ancienta
 * †Ancienta ohioensis
 * Annularia Stellata.jpg †[[Annularia]]
 * †Annularia asteris
 * †Annularia radiata
 * †Annularia sphenophylloides
 * †Annularia stellata
 * †Anomalocrinus
 * †Anomalodonta
 * †Anomalodonta costata
 * †Anomalotoechus
 * †Anomalotoechus tuberatus
 * †Anostylostroma
 * †Anostylostroma columnare
 * †Anostylostroma laxum
 * †Anozyga – type locality for genus
 * †Anozyga bulla – type locality for species
 * †Anthracodromeus
 * †Anthracodromeus longipes – type locality for species
 * †Anthracopupa – type locality for genus
 * †Anthracopupa ohioensis – type locality for species
 * Anthracosaurus russeli12DB.jpg †[[Anthracosaurus]]
 * †Anthracosaurus lancifer – type locality for species
 * †Antiquaster
 * †Antiquaster magrumi
 * †Antiquatonia
 * †Antiquatonia costata
 * †Antiquatonia portlockianus
 * †Aparchites
 * †Aparchites minutissimus
 * †Aparchites oblongus
 * †Aphelakardia
 * †Aphelakardia alternistriata
 * †Aphlebia
 * †Apiculatasporites
 * †Apiculatasporites acueatus
 * †Apiculatasporites latigranifer
 * †Apiculatasporites saetiger
 * †Apiculatasporites setulosus
 * †Arabellites
 * Archaeothyris NT small.jpg †[[Archaeothyris]]
 * †Archegogryllus – type locality for genus
 * †Archegogryllus priscus – type locality for species
 * †Archinacella
 * †Archinacella rugatina
 * †Arcochiton – type locality for genus
 * †Arcochiton raymondi – type locality for species
 * Arctinurus boltoni.jpg †[[Arctinurus]]
 * †Arjamannia
 * †Arjamannia inexpectans
 * †Armenoceras
 * †Arthraria
 * †Arthraria biclavata
 * †Arthroacantha
 * †Arthroacantha carpenteri
 * †Arthropitys
 * Arthropoma
 * †Arthropoma shafferi
 * †Arthrostylus
 * †Artisia
 * †Ascodictyon
 * †Ascodictyon fusiforme
 * †Asolanus
 * †Asolanus camptotaenia
 * †Asolanus sigillarioides
 * †Aspidopora
 * †Aspidopora newberryi
 * †Astartella
 * †Astartella clinata – type locality for species
 * †Astartella concentrica
 * †Astartella varica
 * †Astartella vera
 * †Asterotheca
 * †Atactoblatta – type locality for genus
 * †Atactoblatta anomala – type locality for species
 * †Atactoechus
 * †Atactoechus typicus – or unidentified comparable form
 * †Atactopora
 * †Atactoporella
 * †Ateleocystites
 * †Athyris
 * †Athyris vittata
 * †Atraktoprion
 * †Atrypa
 * Atrypa reticularis pedunculate Gondelsheim CRF.jpg †[[Atrypa reticularis]]
 * †Atrypa reticularus – report made of unidentified related form or using admittedly obsolete nomenclature
 * †Augustoceras
 * †Aulacella
 * †Aulacera
 * †Aulacera nodulosa
 * †Aulocystis
 * †Aulocystis auloporoidea
 * †Aulocystis auloporoides
 * †Aulocystis flabellata
 * †Aulocystis jacksoni
 * †Aulocystis lucasensis
 * †Aulopora
 * †Aulopora microbuccinata
 * †Aulopora serpens
 * †Austinella
 * †Austinella scovellei
 * Aviculopecten subcardiformis01.JPG †[[Aviculopecten]]
 * †Aviculopecten appalachianus – type locality for species
 * †Aviculopecten columbianus – type locality for species
 * †Aviculopecten coxanus
 * †Aviculopecten fasciculatus
 * †Aviculopecten occidentalis
 * †Aviculopecten princeps
 * †Aviculopecten winchelli
 * †Aviculopinna
 * †Aviculopinna peracuta

B

 * †Bactrites – tentative report
 * †Bactrites arkonensis – or unidentified comparable form
 * Bairdia
 * †Bairdia devonica
 * †Balbiniconcha
 * †Balbiniconcha hebe
 * †Baldwinonus
 * †Baldwinonus dunkardensis
 * †Barathrisphaeridium
 * †Barathrisphaeridium chagrinense
 * †Barathrisphaeridium pumilispinosum
 * †Barbclabornia
 * †Barbclabornia luedersensis
 * †Barychilina
 * †Batostoma
 * †Batostoma varians
 * †Batostomella
 * †Batostomella gracilis
 * †Batostomella striata
 * †Baylea
 * †Baylea giffordi – or unidentified comparable form
 * †Baylea inclinata – type locality for species
 * †Beatricea
 * †Beatricea undulata
 * Bellerophon umbilicalis.jpg †[[Bellerophon (genus)|Bellerophon]]
 * †Bellerophon hyalina
 * †Bellerophon jeffersonensis
 * †Bellerophon newberryi
 * †Bellerophon pelops
 * †Bellerophon spergensis
 * †Bellerophon stevensianus
 * †Bellerophon stummi – type locality for species
 * †Bellerophon whittleseyi – type locality for species
 * †Belodella
 * †Beloitoceras
 * †Beloitoceras amoenum
 * †Bembexia
 * †Bembexia adjutor – type locality for species
 * †Bembexia insolita
 * Berenicea
 * †Bethanyphyllum
 * †Bethanyphyllum robustum
 * †Bicarina
 * †Bicarina petilitornata
 * †Bickmorites
 * †Bikocrinus
 * †Bikocrinus baios
 * †Billingsastraea
 * †Billingsastraea longicarinata
 * †Billingsastrea
 * †Billingsastrea longicarinata
 * †Blattinopsis
 * †Blattinopsis americana – type locality for species
 * †Blattinopsis anthracina – type locality for species
 * †Blattinopsis latipennis – type locality for species
 * †Bodmania
 * †Bollia
 * †Bollia persulcata
 * †Bollia regularis
 * †Botryllopora
 * †Botryllopora socialis
 * †Botryocrinus
 * †Botryocrinus neimani
 * †Bowmanites
 * †Bowmanites incurvata
 * †Bowmanites magna
 * †Brachiospongia
 * Brachydectes.jpg  †[[Brachydectes]] – type locality for genus
 * †Brachydectes newberryi – type locality for species
 * †Brockocystis
 * †Brockocystis nodosaria
 * †Broiliellus
 * †Broiliellus hektotopos – type locality for species
 * †Bucanella
 * †Bucania
 * †Bucania crassa
 * †Bucanopsis
 * †Buthotrephis
 * †Buthotrephis gracilis
 * †Byssonychia
 * †Byssonychia grandis
 * †Byssonychia radiata
 * Bythocypris
 * †Bythocypris cylindrica
 * †Bythocypris punctatus
 * †Bythopora
 * †Bythopora delicatula
 * †Bythopora striata

C

 * Calamites stems.JPG †[[Calamites]]
 * †Calamites carinatus
 * †Calamites cisti
 * †Calamites citiifromis
 * †Calamites sachsi
 * †Calamites schützeiformis
 * †Calamites suckowi
 * †Calamites suckowii
 * †Calamites undulatus
 * †Calamospora
 * †Calamospora breviradiata
 * †Calamospora hartungiana
 * †Calamospora straminea
 * †Calamostachys
 * †Calamostachys bisporangiata – type locality for species
 * †Calamostachys germanica
 * †Calamostachys interculata – type locality for species
 * †Calamostachys longibracteata – type locality for species
 * †Calamostachys minuta – type locality for species
 * †Calamostachys recurvata – type locality for species
 * †Calamostachys tuberculata
 * †Calapoecia
 * †Calceocrinus
 * †Calceocrinus incertus
 * †Callipleura
 * †Callipleura nobilis – or unidentified comparable form
 * Callixylon whiteanum.jpg †[[Callixylon]]
 * †Callixylon clevelandensis
 * †Callixylon newberryi
 * †Calloporella
 * †Calostylis – tentative report
 * †Calostylis lindstroemi
 * †Calvibembexia
 * †Calvibembexia sulcomarginata
 * †Camarotoechia
 * †Camarotoechia semiplicata
 * Cameroceras trentonese.jpg †[[Cameroceras]]
 * †Cardiocarpon
 * †Cardiomorpha
 * †Cardiomorpha missouriensis
 * †Carneyella
 * †Carneyella foerstei
 * †Caryocrinites
 * †Catazone
 * †Catazone eversolensis – type locality for species
 * †Catazyga
 * †Catazyga headi
 * Museum Mensch und Natur - catenipora.jpg †[[Catenipora]]
 * †Catenipora favositomima
 * †Catenipora favositomina
 * †Catenipora gotlandica
 * †Caulopteris
 * †Caulopteris antiqua
 * †Caulopteris peregrina
 * †Cayugaea
 * †Cayugaea intermittens
 * †Cayugaea transitorius – tentative report
 * †Centroceras
 * †Centrorhynchus (= Sartenaerus)
 * †Ceramoporella
 * †Ceramoporella granulosa
 * †Ceramoporella ohioensis
 * †Ceratocephala
 * †Ceratoikiscum
 * †Ceratoikiscum bujugum
 * †Ceratoikiscum spinosiarcuatum
 * †Ceratoikiscump
 * †Ceratoikiscump erittacanthinum
 * †Ceratoikiscump lanistellare
 * †Ceratopsis
 * †Ceratopsis chambersi
 * †Ceratopsis oculifera
 * †Ceraurinus
 * †Ceraurinus icarus
 * †Ceraurus
 * †Chaenomya
 * †Chaenomya leavenworthensis
 * †Chagrinia
 * †Chagrinichnites
 * †Charactoceras
 * †Chasmatopora
 * Trilobit IGP4540.jpg †[[Chasmops]]
 * †Chaunograptus
 * †Chiloporella
 * †Chlidochirus
 * †Chlidochirus springeri
 * †Chondrites
 * †Chonetes
 * †Chonetes aurora – tentative report
 * †Chonetes deflectus
 * †Chonetes minutus
 * †Chonetes mucronatus – tentative report
 * †Chonetina
 * †Chonetina choteauensis
 * †Chonetinella
 * †Chonetinella flemingi
 * †Chonetinella verneuilana
 * †Chonetinella verneuiliana
 * †Cincinnaticrinus
 * †Cincinnatidiscus
 * Cincinnetina meeki (Miller, 1875) slab 3.jpg †[[Cincinnetina]]
 * †Cincinnetina meeki
 * †Cincinnetina multisecta
 * †Cirratriradites
 * †Cirratriradites annulatus
 * †Cladochonus
 * †Cladopora
 * †Cladopora bifurcata
 * †Cladopora crassa
 * †Cladopora lucasensis
 * †Cladopora minuitissima
 * †Cladopora roemeri
 * Cladoselache fyleri fossil.jpg †[[Cladoselache]]
 * †Cladoselache clarki
 * †Clarkesvillia
 * †Clathrodictyon
 * †Clathrodictyon confertum
 * †Clathrospira
 * †Claudeonychia – type locality for genus
 * †Claudeonychia babini – type locality for species
 * †Cleionychia
 * †Clemetaocrinus
 * †Clemetaocrinus ohioensis
 * †Clevelandodendron
 * †Clevelandodendron ohioensis
 * Climacograptus wilsoni Graptolite Fossils from Dob%27s Linn Scotland.jpg †[[Climacograptus]]
 * †Clinopistha
 * †Clinopistha radiata
 * †Coelocaulus
 * †Coelocaulus desiderata
 * †Coelocaulus strebloceras – tentative report
 * †Coeloclema
 * †Coeloclema oweni
 * †Coenites
 * †Coleolus
 * †Coleolus iowensis
 * Colosteus NT.jpg †[[Colosteus]]
 * †Colosteus scutellatus – type locality for species
 * †Columnaria
 * †Columnaria calicina
 * †Comasphaeridium
 * †Comasphaeridium caesariatum
 * †Composita
 * †Composita subtilita
 * †Compsocrinus
 * †Compsocrinus harrisi
 * †Conchidium
 * †Conradidium
 * †Conradidium firmamentum
 * †Constellaria
 * †Conularia
 * †Conularia formosa
 * †Convolutispora
 * †Convolutispora mellita
 * †Cordaianthus
 * †Cordaites
 * †Cordaites principalis – or unidentified comparable form
 * †Cornellites
 * †Cornellites flabellum
 * Cornulites cellulosus.jpg †[[Cornulites]]
 * †Cornulites flexuosus
 * †Corocrinus
 * †Corocrinus noduosus
 * †Corynotrypa
 * †Corynotrypa delicatula
 * †Corynotrypa inflata
 * †Corythoecia
 * †Corythoecia dichoptera
 * †Costatulites
 * †Costatulites richmondensis
 * †Cranaena
 * †Cranaena romingeri
 * Craniella
 * †Craniella hamiltonae
 * †Crassisphaeridium
 * †Crassisphaeridium inusitatum
 * †Crassispora
 * †Crassispora kosankei
 * †Crenistriella
 * †Crenistriella rotalinea
 * †Crenulazona
 * †Crenulazona angulata
 * †Crepipora
 * †Crurithyris
 * †Crurithyris planoconvexa
 * †Cryptolithus
 * †Cryptolithus tesselata
 * †Ctenacanthus
 * †Ctenacanthus compressus
 * †Ctenerpeton
 * †Ctenerpeton remex – type locality for species
 * †Ctenobolbina
 * †Ctenobolbina ciliata
 * †Ctenobolbina duryi
 * †Ctenobolbina hammeli
 * †Ctenodonta
 * †Ctenodonta madisonensis
 * †Ctenodonta recurva
 * †Ctenospondylus
 * †Ctenospondylus ninevehensis
 * †Cuffeyella
 * †Cuffeyella arachnoidea
 * †Cunctocrinus
 * †Cunctocrinus fortunatus – type locality for species
 * †Cuneamya
 * †Cuneamya elliptica
 * †Cuneamya miamiensis
 * †Cuneamya scapha
 * †Cupularostrum
 * †Cupularostrum prolificum
 * †Cupulocrinus
 * †Cycloconcha
 * †Cyclocystoides
 * †Cyclogranisporites
 * †Cyclogranisporites microgranus
 * †Cyclogranisporites minutus
 * †Cyclogranisporites obliquus
 * †Cyclogranisporites orbicularis
 * †Cyclonema
 * †Cyclonema bilix
 * †Cyclonema gyronemoides
 * †Cyclonema humerosum
 * †Cyclonema minuta
 * Cyclopteris fossil cropped.png †[[Cyclopteris]]
 * †Cyclopteris orbicularis
 * †Cyclopteris trichomanoides
 * †Cyclora
 * †Cyclora depressa
 * †Cyclora hoffmani
 * †Cyclora parvula
 * †Cyclora pulcella
 * †Cyclozyga
 * †Cyclozyga attenuata – type locality for species
 * †Cyclozyga mirabilis
 * †Cylindrocoelia
 * †Cylindrophyllum
 * †Cylindrophyllum delicatulum
 * †Cylindrophyllum delicatum
 * †Cylindrophyllum profundum
 * †Cymatiosphaera
 * †Cymatiosphaera acinosa
 * †Cymatiosphaera adaiochorata
 * †Cymatiosphaera brevicrista
 * †Cymatiosphaera daioariochora
 * †Cymatiosphaera labyrinthica
 * †Cymatiosphaera parvicarina
 * †Cymatiosphaera rhacoamba
 * †Cymatiosphaera velicarina
 * †Cymatonota
 * †Cymatonota constricta
 * †Cymatonota cylindrica
 * †Cymatonota parallela
 * †Cymatonota recta
 * †Cymatonota semistriata
 * †Cymatospira
 * †Cymatospira alternodosa – type locality for species
 * †Cymatospira montfortianus
 * †Cyperites
 * †Cyphotrypa
 * †Cyphotrypa clarksvillensis
 * †Cypricardinia
 * †Cypricardinia indenta
 * Cypridina
 * †Cypridina herzeri
 * †Cyrtentactinia
 * †Cyrtentactinia cibdelosphaera
 * †Cyrtentactinia primotica
 * †Cyrtina
 * †Cyrtina alpenensis
 * †Cyrtina hamiltonensis
 * †Cyrtina umbonata
 * †Cyrtocerina
 * †Cyrtodonta
 * †Cyrtodonta halli
 * †Cyrtodontula
 * †Cyrtolites
 * †Cyrtolites claysferryensis
 * †Cyrtolites inornatum
 * †Cyrtolites ornatus
 * †Cyrtolites retrorsus
 * †Cyrtospira
 * †Cyrtospira directus
 * Cyrtospirifer verneuili duo.jpg †[[Cyrtospirifer]]
 * †Cystaster
 * †Cystiphylloides
 * †Cystiphylloides americanum
 * †Cystodictya
 * †Cystodictya hamiltonensis
 * †Cystodictya incisurata
 * Cythere
 * †Cythere ohioensis
 * Cytherella
 * †Cytherella unioniformis

D

 * †Dalmanella
 * †Danaeites
 * †Danaeites emersonii
 * Decadocrinus crinoid.jpg †[[Decadocrinus]]
 * †Decadocrinus hughwingi
 * †Decadocrinus stewartae
 * †Decadocrinus wrightae
 * †Deceptrix
 * †Deceptrix albertina
 * †Dechenella
 * †Dechenella alpenensis
 * †Dechenella lucasensis
 * †Dekayella
 * †Dekayia
 * †Deltodus
 * †Deltoidospora
 * †Deltoidospora levis
 * †Deltoidospora priddyi
 * †Denayella
 * †Denayella rotalia
 * †Dendrocrinus
 * †Dendrocrinus daytonensis
 * †Derbyia
 * †Derbyia crassa
 * †Dermatostroma
 * †Dermatostroma scabrum
 * †Desmoinesia
 * †Desmoinesia muricatina
 * †Devonalosia
 * †Devonalosia wrightorum
 * †Devonochonetes
 * †Devonochonetes coronatus
 * †Devonochonetes fragilis
 * †Devonochonetes scitulus
 * †Devonorhineoderma
 * †Devonorhineoderma hyphantes
 * †Diaphorochroa
 * †Diaphorochroa ganglia
 * †Dicalamophyllum
 * Diceratosaurus.jpg †[[Diceratosaurus]]
 * †Diceratosaurus brevirostris – type locality for species
 * †Dicranopora
 * †Dicranopora emacerata
 * †Dictyoclostus
 * †Dictyoclostus semireticulatus
 * †Dictyonema
 * †Dictyotomaria
 * †Dictyotomaria capillaria
 * †Dictyotomaria scitula – or unidentified comparable form
 * †Diestoceras
 * †Diestoceras eos
 * †Diestoceras indianense
 * †Diestoceras shideleri
 * †Diexallophasis
 * †Diexallophasis absona
 * †Diexallophasis cuspidis
 * †Dinichthys
 * †Dinichthys herzeri
 * †Dinophyllum
 * †Dinophyllum semilunum
 * †Dinophyllum stokesi
 * †Dinorthis
 * †Dinorthis carleyi
 * †Diphyphyllum
 * Diploceraspis.jpg †[[Diploceraspis]]
 * †Diplograptus
 * †Diplograptus recurrens
 * Discina
 * †Discotrypa
 * †Dithyrocaris
 * †Dithyrocaris neptuni – or unidentified comparable form
 * †Ditomopyge
 * †Ditomopyge decurtata
 * †Ditomopyge scitula
 * †Divietipellis
 * †Divietipellis robusta
 * The Eurypterida of New York plate 40.jpg †[[Dolichopterus]]
 * †Dolichopterus asperatus
 * †Donaldiella
 * †Donaldina
 * †Donaldina bellilineata – or unidentified comparable form
 * †Donaldina pygmaea – tentative report
 * †Donaldina robusta – type locality for species
 * †Donaldina stevensana – type locality for species
 * †Dorsennidium
 * †Dorsennidium patulum
 * †Doryblatta – type locality for genus
 * †Doryblatta longipennis – type locality for species
 * †Douvillina
 * †Douvillina distans
 * †Drepanella
 * †Drepanella richardsoni
 * †Drepanoistodus
 * †Drymocrinus
 * †Drymocrinus geniculatus
 * †Dunbarella
 * †Dunbarella knighti – or unidentified comparable form
 * †Dunbarella striata
 * Dunkleosteus intermedius.jpg †[[Dunkleosteus]]
 * †Dunkleosteus raveri – type locality for species
 * †Dvorakia
 * †Dystactocrinus
 * †Dystactocrinus constrictus
 * †Dystactospongia

E

 * †Ecclimadictyon
 * †Ecdyceras
 * †Ecdyceras foerstei
 * †Echinocaris
 * †Echinocaris multinodosa
 * †Echinocaris multispinosis
 * †Echinocaris ohioensis – type locality for species
 * †Echinocaris pulchra – type locality for species
 * †Echinocaris punctata
 * †Echinocaris sublevis
 * †Echinocoelia
 * †Echinoconchus
 * †Echinoconchus punctatus
 * †Echinolichas
 * †Echinolichas lucasensis
 * †Ecmelostoiba
 * †Ecmelostoiba asymmetrica
 * †Ecmelostoiba leptoderma
 * †Economolopsis
 * †Economolopsis anodontoides
 * †Ectenocrinus
 * †Ectenocrinus simplex
 * †Ecthymabrachion
 * †Ecthymabrachion camptos
 * †Edmondia
 * †Edmondia aspenwallensis
 * †Edmondia aspinwallensis
 * †Edmondia nebrascensis
 * †Edmondia nodulifera – type locality for species
 * †Edon
 * †Edon oblonga
 * †Elasmonema
 * †Elasmonema bellatula
 * †Elasmonema clarki
 * †Elasmonema corrugata – type locality for species
 * †Elasmonema imitator
 * †Elasmonema lichas
 * [[File:Eldredgeops milleri, Middle Devonian, Silica Shale, Sylvania, Ohio, USA - Houston Museum of Natural Science - DSC01523.JPG|thumb|right|Fossil found near Sylvania of the Middle-Late Devonian trilobite Eldredgeops]] †[[Eldredgeops]]
 * †Eldredgeops rana
 * †Elegantilites – tentative report
 * †Elektoriskos
 * †Elektoriskos apodasmios
 * †Elektoriskos arcetotricus
 * †Elektoriskos lasios
 * †Eliasopora
 * †Eliasopora stellatum
 * †Elita
 * †Elpe
 * †Elpe cincinnatiensis
 * †Elpe irregularis
 * †Elpe ulrichi
 * †Elrodoceras
 * †Emmonsia
 * †Emmonsia arbuscula
 * †Emmonsia radiciformis
 * †Endelocrinus
 * †Endelocrinus kieri – type locality for species
 * Endoceras.JPG †[[Endoceras]]
 * †Endosporites
 * †Endosporites globiformis
 * †Endosporites plicatus
 * †Endosporites zonalis
 * †Endothyra
 * †Endothyra kennethi
 * †Endothyranella
 * †Endothyranella inflata
 * †Endothyranella intermissa
 * †Endothyranella minuta – or unidentified comparable form
 * †Endothyranella nitida – or unidentified comparable form
 * †Endothyranella stormi – or unidentified comparable form
 * †Entactinia
 * †Entactinia additiva
 * †Entactinia cometes
 * †Entactinia crustescens
 * †Entactinia exilispina
 * †Entactinia herculea
 * †Entactinia micula
 * †Entactinia monalloea
 * †Entactinia pantosompha
 * †Entactinia paula
 * †Entactinia quantilla
 * †Entactinia somphorhips
 * †Entactinia spongites
 * †Entactinia sychnacanthina
 * †Entactinosphaera
 * †Entactinosphaera diplostraca
 * †Entactinosphaera dystactotata
 * †Entactinosphaera echinata – tentative report
 * †Entactinosphaera erebenna
 * †Entactinosphaera esostrongyla
 * †Entactinosphaera euthlasta
 * †Entactinosphaera fredericki
 * †Entactinosphaera hapala
 * †Entactinosphaera hystricosa
 * †Entactinosphaera inusitata
 * †Entactinosphaera polyacanthina
 * †Entactinosphaera riedeli
 * †Entactinosphaera symphypora
 * †Entactinosphaera tretactinia
 * †Entactinosphaera variacanthina
 * †Entactinosphaerap
 * †Entactinosphaerap alimbola
 * †Enteletes
 * †Enteletes hemiplicata
 * †Eochonetes
 * †Eochonetes clarksvillensis
 * †Eochonetes clarkvillensis
 * †Eomarginifera
 * †Eomarginifera longispinus
 * †Eomyelodactylus
 * †Eomyelodactylus rotundatus
 * †Eomylodactylus
 * †Eomylodactylus rotundatus
 * †Eotrophina
 * †Ephelopalla
 * †Ephelopalla elongata
 * †Ephelopalla talea
 * Erettopterus osiliensis.jpg †[[Erettopterus]]
 * †Erettopterus saetiger
 * †Eridoconcha
 * †Eridoconcha rugosa
 * †Eridorthis
 * †Eridotrypa
 * †Erisocrinus
 * †Erisocrinus typus
 * †Erpetosaurus
 * †Erpetosaurus radiatus – type locality for species
 * †Escharopora
 * †Estiastra
 * †Estiastra culcita
 * †Estiastra dilatostella
 * †Estiastra rugosa
 * CrinoidHoldfastRoots.JPG †[[Eucalyptocrinites]]
 * †Euchondria
 * †Euchondria neglecta
 * †Euchondria ohioensis – type locality for species
 * †Euchondria pellucida
 * †Euconospira
 * †Euconospira turbiniformis
 * †Eunicites
 * †Euomphalus
 * †Euomphalus planodorsatus
 * †Euomphalus similis
 * †Euphemites
 * †Euphemites carbonarius
 * †Euphemites enodis – type locality for species
 * †Euphemites multiliratus – type locality for species
 * †Euphemites nodocarinatus
 * †Euphemites subglobosus
 * †Euphemites vittatus
 * †Eurymya
 * †Euryocrinus – tentative report
 * †Euryocrinus laddii
 * Eurypterus Paleoart.jpg †[[Eurypterus]]
 * †Eurypterus ornatus
 * †Eusauropleura – type locality for genus
 * †Eusauropleura digitata – type locality for species
 * †Eutaxocrinus
 * †Eutaxocrinus wideneri
 * †Evenkiella
 * †Exilisphaeridium
 * †Exilisphaeridium simplex
 * †Exochoderma
 * †Exochoderma irregulare
 * †Exochoderma ramibrachium

F
0 Links
 * †Faberia
 * †Faberia anomala
 * †Faberoceras
 * †Favistella
 * FavositesOrdovicianIndiana.jpg †[[Favosites]]
 * †Favosites dentistabulatus
 * †Favosites discoideus
 * †Favosites favosus
 * †Favosites hamiltonae
 * †Favosites hamiltoniae
 * †Favosites hisingeri
 * †Favosites turbinatus
 * †Fayettoceras
 * †Fenestella
 * †Fenestella shumardi
 * †Fenestrellina
 * †Fenestrellina rockportensis
 * †Fistulipora
 * †Fistulipora vesiculata
 * Flexicalymene-ouzregui-rolled.jpg †[[Flexicalymene]]
 * †Flexicalymene meeki
 * †Florinites
 * †Florinites florini
 * †Florinites mediapudens
 * †Florinites milloti
 * †Florinites similis
 * †Florinites visendus
 * †Foerstia
 * †Foerstia ohioensis
 * †Fusispira
 * Fusulinid limestone, Upper Pennsylvanian; Elk County KS.jpg †Fusulina
 * †Fusulina secalica

G

 * †Gamizyga
 * †Gamizyga corpulentissima
 * †Gamizyga girtyi – type locality for species
 * †Gamizyga morningstarae
 * †Gerablattina
 * †Gerablattina richmondiana – type locality for species
 * †Gigantopteris – or unidentified comparable form
 * Rhodocrinidae - Gilbertsocrinus tuberosus.JPG †[[Gilbertsocrinus]]
 * †Gilbertsocrinus alpenensis
 * †Gilbertsocrinus ohioensis
 * †Gillespieisporites
 * †Gillespieisporites venustus
 * †Girtyspira
 * †Girtyspira minuta
 * †Glabrocingulum
 * †Glabrocingulum beedei – type locality for species
 * †Glabrocingulum grayvillense
 * †Glabrocingulum stellaeformis
 * †Glabrocingulum wannense – or unidentified comparable form
 * †Globodoma
 * †Globodoma nodosa
 * †Globozyga
 * †Globozyga reticulata
 * †Globozyga subcorpulenta – type locality for species
 * †Glossites
 * †Glossites subtenuis
 * †Glyptocardia
 * †Glyptocardia speciosa
 * Glyptocrinidae - Glyptocrinus decadactylus cropped.jpg †[[Glyptocrinus]]
 * †Glyptocrinus richardsoni
 * †Glyptorthis
 * †Glyptorthis daytonensis – type locality for species
 * †Glyptorthis fausta – type locality for species
 * †Glyptorthis insculpta
 * †Gomphostrobus
 * †Goniasma
 * †Goniasma lasallense – or unidentified comparable form
 * †Gonioloboceras
 * †Gorbyoceras
 * †Gorogonisphaeridium
 * †Gorogonisphaeridium absitum
 * †Gorogonisphaeridium elongatum
 * †Gorogonisphaeridium evexispinosum
 * †Gorogonisphaeridium ohioense
 * †Gorogonisphaeridium plerispinosum
 * †Gorogonisphaeridium separatum
 * †Gosseletia
 * †Gosseletia triquetra
 * †Gosselettia
 * †Gosselettia triquetra
 * †Graciloceras
 * †Grammysia
 * †Grammysia arcuata
 * †Grammysia bellatula
 * †Grammysia bisulcata
 * †Grammysia constricta
 * †Grammysia nodocostata
 * †Grammysia sylvanensis
 * †Grammysioidea
 * †Granasporites
 * †Granasporites medius
 * †Granulatisporites
 * †Granulatisporites granulatus
 * †Granulatisporites minutus
 * †Granulatisporites parvus
 * †Granulatisporites piroformis
 * †Graptodictya
 * †Graptodictya perelegans
 * RugosaOrdovician.jpg †[[Grewingkia]]
 * †Grewingkia rusticum
 * †Guttatisphaeridium
 * †Guttatisphaeridium pandum
 * †Gypidula

H

 * †Habrostroma
 * †Habrostroma beachvillensis
 * †Habrostroma larocquei
 * †Habrostroma marpleae
 * †Hallinetes
 * †Hallinetes setigera
 * Hallopora multitabulata fossil bryozoan (Ordovician; Frankfort IL.jpg †[[Hallopora]]
 * †Hallopora bassleri
 * †Hallopora flabellaris
 * †Hallopora libana
 * †Hallopora nicklesi
 * †Hallopora subnodosa
 * †Halysites
 * †Halysites catenularis
 * †Halysites catenularius
 * †Halysites nitidus
 * †Hamiltonella
 * †Hamiltonella punctulifera
 * †Haplentactinia
 * †Haplentactinia arrhinia
 * †Haplentactinia rhinophyusa
 * †Hawletrochus
 * †Hawletrochus macrostomus
 * †Hebertella
 * †Hebertella alveata
 * †Hebertella occidentalis
 * †Hebertella sinuata
 * †Hebertella subjugata
 * †Hebertocaris
 * †Hebertocaris wideneri
 * †Hederella
 * †Hederella alpenensis
 * †Hederella bilineata
 * †Hederella cirrhosa
 * †Hederella concinnoides
 * †Hederella delicatula
 * †Hederella filiformis
 * †Hederella magna
 * †Hederella parvirugosa
 * †Hederella rectifurcata
 * †Hederella reimanni
 * †Hederella thedfordensis
 * †Hederella vagans
 * †Helcionopsis
 * †Helicelasma
 * †Helicelasma rusticum
 * †Helicotoma
 * †Heliolites
 * Heliophyllum halli Bethany Center Centerfield 2.jpg †[[Heliophyllum]]
 * †Heliophyllum bathycalyx
 * †Heliophyllum halli
 * †Heliophyllum microcarinatum
 * †Helminthochiton
 * †Helminthochiton simplex
 * †Helminthozyga
 * †Helminthozyga costellata – type locality for species
 * †Helminthozyga undulata – type locality for species
 * †Helopora
 * †Helopora inexpectata
 * †Hemicystites
 * †Hemiphragma
 * †Hemizyga
 * †Hemizyga attenuata
 * †Hemizyga elegans – or unidentified comparable form
 * †Hemizyga illineata – or unidentified comparable form
 * †Heracloceras – tentative report
 * †Heracloceras inelegans – tentative report
 * †Hercostrophia
 * †Hercostrophia robusta
 * †Heslerodus
 * †Heslerodus divergens
 * †Hessonia
 * †Hessonia priscus
 * †Heterocrinus
 * †Heterocrinus exiguus
 * †Heterocrinus exilis
 * †Heterocrinus heterodactylus
 * †Heterocrinus juvenis
 * †Heterocrinus pentagonus
 * †Heteronema – tentative report
 * †Heterophrentis
 * †Heterophrentis simplex
 * †Heterorthina
 * †Heterorthina fairmountensis
 * †Heterotrypa
 * Hexagonaria percarinata close view.JPG †[[Hexagonaria]]
 * †Hexagonaria anna
 * †Hexagonaria stewartae
 * †Hexagonaria tabulata
 * †Hexagonaria truncata
 * †Hexameroceras
 * †Hindella
 * †Hindia
 * †Hippocardia
 * †Hippocardia herricki – type locality for species
 * †Hippocardia hydei – type locality for species
 * †Hippocardia monroica
 * †Hippocardia ohioense
 * †Hiscobeccus
 * †Hiscobeccus capax
 * †Hoareicardia
 * †Hoareicardia cunea
 * †Holoeciscus
 * †Holoeciscus auceps
 * Holopeidae - Holopea praestans.JPG †[[Holopea]]
 * †Holoptychus – or unidentified comparable form
 * †Holtedahlina
 * †Holtedahlina sulcata
 * †Homotrypa
 * †Homotrypa wortheni
 * †Homotrypella
 * †Homotrypella dubia
 * †Hormotoma
 * †Hormotoma centervillensis – type locality for species
 * †Hormotomina
 * †Hormotomina maia
 * †Hudsonaster
 * †Hudsonaster incomptus
 * †Hustedia
 * †Hustedia mormoni
 * †Hyattidina
 * Hyoliths02.JPG]] †Hyolithes''
 * †Hyolithes dubius
 * †Hyolithes parviusculus
 * †Hyolithes versaillensis
 * †Hypergonia
 * †Hypergonia jonathanensis – type locality for species
 * †Hyperoblastus
 * †Hyperoblastus reimanni
 * †Hyphantozyga
 * †Hyphantozyga cancellata – type locality for species
 * †Hyphantozyga fusiforma – type locality for species
 * †Hyphantozyga gracilis
 * †Hyphantozyga grandis – type locality for species
 * †Hyphantozyga knighti
 * †Hyphantozyga perattenuata
 * †Hyphantozyga pulchra
 * †Hyphantozyga textilis – type locality for species
 * †Hypselentoma
 * †Hypselentoma inornata
 * †Hystriculina
 * †Hystriculina wabashensis

I

 * †Ianthinopsis
 * †Ianthinopsis melanoides – type locality for species
 * †Ibanocrinus
 * †Ibanocrinus petalos
 * †Ichthyerpeton
 * †Ichthyerpeton squamosum – type locality for species
 * †Icriodus
 * †Icriodus angustus
 * †Icriodus arkonensis
 * †Icriodus brevis
 * †Icriodus eriensis
 * †Icriodus excavatus
 * †Icriodus expansus
 * †Icriodus janeae
 * †Icriodus lindensis
 * †Icriodus obliquimarginatus
 * †Icriodus ohioensis
 * †Icriodus platyobliquimarginatus
 * †Icriodus regularicrescens
 * †Indospora
 * †Indospora stewartii
 * †Intrapora
 * †Intrapora irregularis
 * †Iocrinus
 * †Ischyrodonta
 * †Ischyrodonta truncata
 * †Ischyrodonta unionoides
 * †Isodectes
 * †Isodectes obtusus – type locality for species
 * †Isonema
 * †Isonema depressum
 * †Isorophus
 * †Isorophus austini
 * †Isorophus holbrooki
 * †Isorophus warrenensis
 * †Isorthoceras
 * †Isorthoceras albersi
 * Isotelus brachycephalus.JPG †[[Isotelus]]
 * †Isotelus maximus
 * †Isotelus megistos

J

 * †Jedria
 * †Jedria ventrica
 * †Jonesella
 * †Jonesella crepidiformis
 * †Jonesella pedigera
 * †Jonesites
 * †Jonesites inornatus
 * †Jonesites marginatus
 * †Jugiaster
 * †Jugiaster speciosus
 * †Juresania
 * †Juresania ovalis

K

 * †Kindleoceras
 * Kionoceras doricum.JPG †[[Kionoceras]]
 * †Kockelella
 * †Kockelella ortus
 * †Kockelella ranuliformis
 * †Kockelella walliseri
 * †Kophinocrinus – tentative report
 * †Kophinocrinus magrumi – tentative report
 * †Kyreocrinus
 * †Kyreocrinus constellatus

L

 * †Labechia
 * †Laccoprimitia
 * †Laccoprimitia centralis
 * †Laevigatosporites
 * †Laevigatosporites desmoinesensis
 * †Laevigatosporites globosus
 * †Laevigatosporites medius
 * †Laevigatosporites minimus
 * †Laevigatosporites minor
 * †Laevigatosporites ovalis
 * †Laevigatosporites subadnatoides
 * †Laevigatosporites vulgaris
 * †Lambeoceras
 * †Lanthanaster
 * †Lanthanaster cruciformis – type locality for species
 * †Lasiograptus
 * †Latericriodus
 * †Latericriodus latericrescens
 * †Latosporites
 * †Latosporites minutus
 * †Lechritrochoceras
 * †Leioclema
 * †Leioclema alpenense
 * †Leioclema alpense
 * †Leiorhynchus
 * †Leiorhynchus kelloggi
 * †Leiorhynchus laura
 * †Leiorhynchus lucasi
 * †Leiosphaeridia
 * †Leiotriletes
 * †Leiotriletes granoornatus
 * †Leiotriletes levis
 * †Leiotriletes microsaetosus
 * †Leiotriletes pseudaculeatus
 * †Leiotriletes subadnatoides
 * †Lepadocystis
 * †Leperditia
 * †Leperditia glabra
 * †Lepidocoleus
 * †Lepidocyclus
 * †Lepidocyclus perlamellosum
 * †Lepidocystis
 * LepidodendronOhio.jpg  †[[Lepidodendron]]
 * †Lepidodendron aculeatum
 * †Lepidodendron andrewsi
 * †Lepidodendron jaraczewskii – or unidentified comparable form
 * †Lepidodendron scutatum
 * †Lepidolites
 * †Lepidophloios
 * †Lepidophloios larcinus
 * †Lepidophloios vaningeni
 * †Lepidostrobophyllum
 * †Leptaena
 * †Leptaena gibbosa
 * †Leptaena richmondensis
 * †Leptobolus
 * †Leptobolus insignis
 * †Leptodesma
 * †Leptodesma ausablensis
 * †Leptodesma matheri – or unidentified comparable form
 * †Leptodesma rhysema – type locality for species
 * †Leptograptus
 * †Leptophractus – type locality for genus
 * †Leptophractus obsoletus – type locality for species
 * †Leptopoterion
 * †Leptoptygma
 * †Leptoptygma newtonensis – type locality for species
 * †Leptotrypa
 * †Leptotrypella
 * †Leptotrypella ohioensis
 * †Lescuropteris
 * †Lescuropteris moorii
 * †Levizygopleura
 * †Levizygopleura inornata
 * †Levizygopleura williamsi
 * †Lichenocrinus
 * †Lichenocrinus tuberculata
 * †Limipecten
 * †Limipecten lamellus – type locality for species
 * †Limoptera
 * †Limoptera curvata
 * †Limoptera macroptera
 * Lingula
 * †Lingula carbonaria
 * †Lingula meeki
 * †Lingula melie
 * †Lingulichnus
 * †Lingulops
 * †Linoproductus
 * †Linoproductus cora
 * †Linoproductus prattenianus
 * †Linopteris
 * †Linopteris muensteri
 * †Linopteris neuropteroides
 * †Lioclemella
 * †Liospira
 * †Liospira affinis
 * †Liospira depressum – type locality for species
 * †Liroceras – tentative report
 * †Lodanaria
 * †Lodanaria quadricarinata – type locality for species
 * †Logocrinus – tentative report
 * †Logocrinus brandoni – tentative report
 * †Longispina
 * †Longispina lissohybus
 * †Longstaffia – tentative report
 * †Longstaffia centervillensis – type locality for species
 * †Lopholasma
 * †Lopholasma delawarensis
 * †Lophonychia
 * †Lophonychia cordata
 * †Lophophyllidium
 * †Lophophyllidium profundum
 * †Lophospira
 * †Lophospira milleri
 * †Lophospira perangulata
 * †Lophotriletes
 * †Lophotriletes granoornatus
 * LoxommaB2.jpg †[[Loxomma]]
 * †Loxomma lintonensis – type locality for species
 * †Loxonema
 * †Loxonema pikensis
 * †Loxoplocus
 * †Loxoplocus gothlandicus – type locality for species
 * †Lycospora
 * †Lycospora granulata
 * †Lycospora micropapillata
 * †Lycospora orbicula
 * †Lycospora pellucida
 * †Lycospora pusilla
 * †Lycospora subjuga
 * †Lycospora torquifer
 * †Lyopora
 * †Lyopora goldfussi
 * †Lyriopecten
 * †Lyriopecten mitchelli
 * †Lyrodesma
 * †Lyrodesma major

M

 * †Macrerpeton
 * †Macrerpeton huxleyi – type locality for species
 * †Macrochilina
 * †Macrochilina humilis
 * †Maelonoceras
 * †Manitoulinoceras
 * †Manitoulinoceras gyroforme
 * †Manitoulinoceras williamsae
 * Gephuroceratidae - Manticoceras species.JPG †[[Manticoceras]]
 * †Manticrinus
 * †Manticrinus exaitos
 * †Marsupiocrinus
 * †Maryonychia
 * †Maryonychia concordensis
 * †Mastigograptus
 * †Mastigograptus strictus
 * †Mazostachys
 * †Mazostachys compacta – type locality for species
 * †Mediospirifer
 * †Mediospirifer audaculus
 * †Meekopinna
 * †Meekopinna americana
 * †Meekospira
 * †Meekospira peracuta
 * †Megacanthopora
 * †Megacanthopora fallacis – or unidentified comparable form
 * †Megacystites
 * MegalocephalusDB.jpg †[[Megalocephalus]] – type locality for genus
 * †Megalocephalus lineolatus – type locality for species
 * †Megalograptus
 * †Megastrophia
 * †Megastrophia concava
 * †Megistocrinus
 * †Megistocrinus depressus
 * †Melocrinus
 * †Melocrinus clarkei
 * †Meristospira
 * †Meristospira michiganensis
 * †Merocrinus
 * †Mesocoelia
 * †Mesocoelia obstipisutura
 * †Mesopalaeaster
 * †Mesopalaeaster finei
 * †Mesopalaeaster wilberanus
 * †Mesothyra
 * †Mesotrypa
 * †Mesotrypa orbiculata
 * †Metaxys
 * †Metaxys fossa – type locality for species
 * †Miamoceras
 * †Michelinoceras
 * †Micrhystridium
 * †Micrhystridium adductum
 * †Micrhystridium complurispinosum
 * †Micrhystridium erugatum
 * †Micrhystridium flexibile
 * †Micrhystridium inusitatum
 * †Micrhystridium profusam
 * †Microceras
 * †Microdoma
 * †Microdoma tricarinatus
 * †Microptychis
 * †Microptychis cerithiformis
 * †Microptychis expetendus
 * †Microptychis occabus – type locality for species
 * †Microptychis turbineus
 * †Microreticulatisporites
 * †Microreticulatisporites harrisonii
 * †Microreticulatisporites nobilis
 * †Microreticulatisporites sulcatus
 * †Milleratia
 * †Mitrospermum
 * †Mitrospermum vinculum
 * †Mixoneura
 * †Modiolodon
 * †Modiolodon subovalis
 * †Modiolopsis
 * †Modiolopsis capax
 * †Modiolopsis modiolaris
 * †Modiolopsis versaillesensis
 * Modiolus
 * †Modiolus fountainensis
 * †Modiolus radiatus – type locality for species
 * †Modiolus waverliensis
 * †Modiomorpha
 * †Modiomorpha concentrica
 * †Modiomorpha concentricum
 * †Modiomorpha mytiloides
 * †Modiomorpha subalata
 * †Modiomorpha subalta
 * †Molgophis – type locality for genus
 * †Molgophis macrurus – type locality for species
 * †Monotrypa
 * †Monticulipora
 * †Mourlonia
 * †Mourlonia plena
 * †Mourlonia textus
 * Mucrospirifer mucronatus Silica Shale.JPG †[[Mucrospirifer]]
 * †Mucrospirifer alpenensis
 * †Mucrospirifer grabaui – or unidentified comparable form
 * †Mucrospirifer mucronatus
 * †Mucrospirifer prolificus
 * †Multiplicisphaeridium
 * †Multiplicisphaeridium anastomosis
 * †Multiplicisphaeridium verrucarum
 * †Muraticavea
 * †Muraticavea enteichia
 * †Murchisonia
 * †Murchisonia anderdoniae
 * †Murchisonia dublinensis – type locality for species
 * †Murchisonia gracilicrista
 * †Murchisonia intermedia – type locality for species
 * †Murchisonia leda
 * †Murchisonia minuta
 * †Murchisonia sibleyensis
 * †Murchisonia subcarinata
 * †Murchisonia subulata
 * †Myalina
 * †Myalina pernaformis
 * †Myelodactylus – or unidentified comparable form
 * †Mytilarca
 * †Mytilarca cordata

N

 * †Naevisphaeridium
 * †Naevisphaeridium plenilunium
 * †Narthecoceras
 * †Narthecoceras dunni – type locality for species
 * Neritopsidae - Naticopsis.JPG †[[Naticopsis]]
 * †Naticopsis aequistriata – type locality for species
 * †Naticopsis comperta
 * †Naticopsis genevievensis
 * †Naticopsis levis
 * †Naticopsis ziczac – type locality for species
 * †Navifusa
 * †Navifusa drosera
 * †Neilsonia
 * †Neilsonia uninodocarinata
 * †Neochonetes
 * †Neochonetes granulifer
 * †Neochonetes variolata
 * †Neospirifer
 * †Neospirifer cameratus
 * †Neospirifer dunbari
 * †Nephriticeras – tentative report
 * †Nereidavus
 * †Nereidavus varians
 * †Neumatoceras
 * Neuropteris PAMuseum.jpg †[[Neuropteris]]
 * †Neuropteris heterophylla
 * †Neuropteris ovata
 * †Neuropteris scheuchzeri
 * †Nicholsonella
 * †Nicholsonella peculiaris
 * †Nicollidina
 * †Nicollidina remscheidensis
 * †Nodonema
 * †Nodonema granulatum
 * †Nucleocrinus
 * †Nucleocrinus elegans – or unidentified comparable form
 * Nuculidae - Nucula piacentina.jpg [[Nucula]]
 * †Nucula corbuliformis
 * Nuculana
 * †Nucularca
 * †Nucularca cingulata
 * †Nuculites
 * †Nuculites faberi
 * †Nuculites fabula
 * †Nuculites oblongatus
 * †Nuculites triqueter
 * †Nuculopsis
 * †Nuculopsis beyrichi
 * †Nuculopsis elongata
 * †Nuculopsis girtyi
 * †Nuculopsis shumardana – or unidentified related form
 * † Nyassa
 * †Nyassa recta

O

 * Odonterpeton cropped.png †[[Odonterpeton]] – type locality for genus
 * †Odonterpeton triangulare – type locality for species
 * †Odontopleura
 * †Odontopteris
 * †Odontopteris aequalis
 * †Odontopteris brardii
 * †Oehlertella
 * †Oehlertella stoutella
 * †Oestocephalus – type locality for genus
 * †Oestocephalus amphiuminum – type locality for species
 * †Ohiocrinus
 * †Ohiocrinus laxus
 * †Ohiocrinus oehanus
 * †Olenoides
 * †Onchus
 * †Oncoceras
 * †Onniella
 * †Onychochilus
 * †Onychochilus abruptum – type locality for species
 * †Oomoceras
 * Ophiacodon mirus cropped.png †[[Ophiacodon]]
 * †Ophiacodon uniformis – or unidentified comparable form
 * †Opisthoptera
 * †Opsiocrinus
 * †Opsiocrinus mariae
 * †Orbiculoidea
 * †Orbiculoidea capuliformis
 * †Orbiculoidea herzeri
 * †Orbiculoidea missouriensis
 * †Orbiculoidea newberryi
 * †Orthis – tentative report
 * †Orthoceras
 * †Orthoceras trusitum
 * †Orthoceras type locality for species – informal
 * †Orthodesma
 * †Orthodesma canaliculatum
 * †Orthonema
 * †Orthonema salteri
 * †Orthonema subtaeniatum
 * †Orthonota
 * †Orthonota undulata
 * †Orthonybyoceras – tentative report
 * †Orthonychia
 * †Orthonychia chesterense – tentative report
 * †Orthonychia herzeri
 * †Orthonychia infabricatus – type locality for species
 * †Orthonychia parva
 * †Orthonychia sciotoensis – type locality for species
 * †Orthonychia waverlyensis
 * †Orthopleura
 * †Orthorhynchula
 * †Orthorhynchula linneyi
 * †Ortonella
 * †Oulodus
 * †Oulodus equirectis
 * †Oulodus equirectus
 * †Oxyprora
 * †Oxyprora missouriensis
 * †Ozarkodina
 * †Ozarkodina bohemica
 * †Ozarkodina confluens
 * †Ozarkodina remscheidenesis
 * †Ozarkodina sagitta
 * †Ozarkodina tillmani

P

 * †Pachydictya
 * †Pachydictya bifurcata
 * †Paiderocrinus
 * †Paiderocrinus asketos
 * †Paiderocrinus ochthos
 * †Palacanthus
 * †Palacanthus acutus
 * †Palaeocapulus
 * †Palaeocapulus equilateralis
 * †Palaeocapulus morsei – type locality for species
 * †Palaeoconcha
 * †Palaeolima
 * †Palaeolima retifera
 * †Palaeolima triplistriata
 * †Palaeoneilo
 * †Palaeoneilo bedfordensis
 * †Palaeoneilo bownockeri
 * †Palaeoneilo constricta – or unidentified related form
 * †Palaeoneilo oweni
 * †Palaeonucula
 * †Palaeonucula lunulata – type locality for species
 * †Palaeonucula subrotundata
 * †Palaeopalaemon
 * †Palaeopalaemon elegans – type locality for species
 * †Palaeophycus
 * †Palaeoporites
 * †Palaeoscenidium
 * †Palaeoscenidium cladophorum
 * †Palaeoscenidium quadriramosum
 * †Palaeostachya
 * †Palaeostachya aperta
 * †Palaeostachya decacnema
 * †Palaeostachya elongata
 * †Palaeostachya ovalis
 * †Palaeostachya trabeculata – type locality for species
 * †Palaeostylus
 * †Palaeostylus marvinwelleri
 * †Palaeostylus minuta
 * †Palaeostylus venustus
 * †Palaeotrochus
 * †Palaeotrochus kearnyi
 * †Palaeozygopleura
 * †Palaeozygopleura hamiltoniae
 * †Palaeozygopleura joani
 * †Palaeozygopleura laeviusculum
 * †Palaeozygopleura parvula
 * †Palaeozygopleura sibleyensis
 * †Paleofavosites
 * †Paleofavosites prolificus
 * †paleoporites
 * †Paleschara
 * †Paliphyllum
 * †Paliphyllum brassfieldense
 * †Paliphyllum primarium
 * †Paliphyllum regulare
 * †Panderodus
 * †Panderodus unicostatus
 * †Paracyclas
 * †Paracyclas lirata
 * †Paracyclas proavia
 * †Paracyrtolites
 * †Paracyrtolites carinatus
 * †Paragoniozona
 * †Paragoniozona granulostriata – or unidentified comparable form
 * †Parajuresania
 * †Parajuresania nebrascensis
 * †Paraliospira
 * †Paraliospira rugata
 * †Parallelocrinus
 * †Parallelocrinus sturgeoni – type locality for species
 * †Parallelodon
 * †Parallelodon irvinensis
 * †Parallelodon obsoletus
 * †Parallelodon tenuistriatus
 * [[File:Paraspirifer bownockeri, pyritized brachiopods, Middle Devonian, Silica Shale, Lucas County, Ohio, USA - Houston Museum of Natural Science - DSC01732.JPG|thumb|upright=0.745|Assemblage of the Early-Middle Devonian brachiopod Paraspirifer]] †[[Paraspirifer]]
 * †Paraspirifer bownockeri
 * †Parazyga
 * †Parvohallopora
 * †Parvohallopora onealli
 * †Parvohallopora ramosa
 * †Pasceolus
 * †Pasceolus camdenensis
 * †Patellilabia
 * †Patelliocrinus – type locality for genus
 * †Patelliocrinus planus – type locality for species
 * †Pattersonia
 * †Paupospira
 * †Paupospira bowdeni
 * †Paupospira trilineata – type locality for species
 * †Paupospira tropidophora
 * Pecopteris villosa.jpg †[[Pecopteris]]
 * †Pecopteris arborescens
 * †Pecopteris candolleana
 * †Pecopteris cyathea
 * †Pecopteris hemitelioides
 * †Pecopteris lamuriana
 * †Pecopteris miltonii
 * †Pecopteris unita
 * †Penniretepora
 * †Penniretepora irregularis – or unidentified comparable form
 * †Pennoceras
 * †Pennoceras seamani
 * †Pentamerus
 * †Permophorus
 * †Permophorus oblongus
 * †Permophorus subcostatus
 * †Permophorus tropidophorus
 * †Pernopecten
 * †Pernopecten ohioensis
 * †Pernopecten prosseri
 * †Peronopora
 * †Peronopora decipiens
 * †Petalodus
 * Petalodus ohioensis fossil.jpg]] †Petalodus ohioensis''
 * †Petigopora
 * †Petigopora offfula
 * †Petraster
 * †Petrocrania
 * †Petrocrania hamiltonensis
 * †Petrocrania laelia
 * †Petrocrania modesta
 * †Petrocrania scabiosa
 * †Petrozium
 * †Petrozium pelagicum
 * †Pharkidonotus
 * †Pharkidonotus breyeri – type locality for species
 * †Pharkidonotus labioreflexus – type locality for species
 * †Pharkidonotus percarinatus
 * †Phestia
 * †Phestia inflata
 * †Phestia pandoraeformis
 * †Philhedra
 * †Philhedra crenistriatula
 * Phlegethontia.jpg  †[[Phlegethontia]] – type locality for genus
 * †Phlegethontia linearis – type locality for species
 * †Phlegethontia longissima – type locality for species
 * †Pholadella
 * †Pholadella radiata
 * †Pholadomorpha
 * †Pholadomorpha pholadiformis
 * †Pholidops
 * †Pholidostrophia
 * †Pholidostrophia geniculata
 * †Pholidostrophia gracilis
 * †Pholidostrophia nacrea
 * †Phragmoceras
 * †Phragmolites
 * †Phragmolites elegans – type locality for species
 * †Phragmosphaera
 * †Phragmosphaera lyra
 * †Phylloporina
 * †Phyloblatta
 * †Phyloblatta jeffersoniana – type locality for species
 * †Phymatopleura
 * †Phymatopleura brazoensis
 * †Phymatopleura nodosa
 * †Phyrgilocrinus
 * †Phyrgilocrinus batheri
 * †Phyrtosaster – type locality for genus
 * †Phyrtosaster casteri – type locality for species
 * †Physonemus
 * †Physonemus striatus – or unidentified comparable form
 * †Physotomya
 * †Pianodesma
 * Pinna
 * †Pinna missouriensis
 * †Pityosporites
 * †Pityosporites westphalensis
 * †Placopterina
 * †Placopterina ohioensis – type locality for species
 * Plaesiomyiidae - Plesiomys subquadrata.JPG †[[Plaesiomys]]
 * †Plaesiomys subquadrata
 * †Plagiascetus – type locality for genus
 * †Plagiascetus lateralis – type locality for species
 * †Plagioglypta
 * †Planalveolitella
 * †Planalveolitella parasitica
 * †Planisporites
 * †Planisporites granifer
 * †Planoendothyra
 * †Planoendothyra associata
 * †Planoendothyra evoluta
 * †Planoendothyra orbiculata
 * †Planoendothyra ovata – or unidentified comparable form
 * †Planoendothyra whitesidei – or unidentified comparable form
 * PlatycerasLoganOhio.jpg †[[Platyceras]]
 * †Platyceras attenuatum
 * †Platyceras bucculentum
 * †Platyceras carinatum
 * †Platyceras cymbium
 * †Platyceras erectum
 * †Platyceras lineatum
 * †Platyceras nasutum
 * †Platyceras rarispinum
 * †Platyceras subglobosa – type locality for species
 * †Platyceras thetis
 * †Platycoryphe
 * PSM V72 D566 Pelion lyelli quadraped from carboniferous ohio.png †[[Platyrhinops]] – type locality for genus
 * †Platyrhinops lyelli – type locality for species
 * †Platystrophia
 * †Platystrophia actilirata
 * †Platystrophia acutilirata
 * †Platystrophia annieana
 * †Platystrophia auburnensis
 * †Platystrophia clarksvillensis
 * †Platystrophia corryvillensis
 * †Platystrophia crassa
 * †Platystrophia cummingsi
 * †Platystrophia cypha
 * †Platystrophia elkhornensis
 * †Platystrophia foerstei
 * †Platystrophia hopensis
 * †Platystrophia laticosta
 * †Platystrophia moritura
 * †Platystrophia morrowensis
 * †Platystrophia nitida
 * †Platystrophia pauciplicata
 * †Platystrophia ponderosa
 * †Platystrophia sublaticosta
 * †Platystrophia wallowayi
 * †Plectodina
 * †Plectonotus
 * †Plectonotus boucoti
 * †Plectorthis
 * †Plectorthis aequivalvis
 * †Plectorthis fissicosta
 * †Plectorthis jamesi
 * †Plectorthis neglecta
 * †Plectorthis plicatella
 * †Plethospira
 * Pleurodictyum americanum Kashong.jpg †[[Pleurodictyum]]
 * †Pleurodictyum cornu
 * †Pleurodictyum plana
 * †Pleuronotus
 * †Pleuronotus decewi
 * †Pleuroptyx – type locality for genus
 * †Pleuroptyx clavatus – type locality for species
 * †Pleurorthoceras
 * †Pleurorthoceras clarksvillense
 * †Plexadictyon
 * †Plocezyga
 * †Plocezyga acuminata
 * †Plocezyga conica
 * †Plocezyga cordiformis
 * †Plocezyga costata – type locality for species
 * †Plocezyga delicata
 * †Plocezyga excellens
 * †Plocezyga intermedia
 * †Plocezyga lineata
 * †Plocezyga lirata
 * †Plocezyga markae
 * †Plocezyga ornata – type locality for species
 * †Plocezyga ornatissima
 * †Plocezyga percostata
 * †Plocezyga perminuta
 * †Plocezyga regularia
 * †Plocezyga subnodosa
 * †Plocezyga turbinata
 * †Podolithus
 * †Poleumita
 * †Poleumita incarinatus
 * †Polidevcia
 * †Polidevcia bellistriata
 * †Polidevcia stevensiana
 * †Polyentactinia
 * †Polyentactinia craticulata
 * †Polyentactinia leptosphaera
 * †Polyentactinia plecta
 * †Polyentactinia polygonia
 * Polygnathus Pa elements.png †[[Polygnathus]]
 * †Polygnathus eiflius
 * †Polygnathus intermedius
 * †Polygnathus linguiformis
 * †Polygnathus pseudofoliatus
 * †Polygnathus strongi
 * †Polygnathus xylus
 * †Polypora
 * †Polypora valida – or unidentified comparable form
 * Pontocypris
 * †Pontocypris acuminata
 * †Poroblattina
 * †Poroblattina brachyptera – type locality for species
 * †Poroblattina lata – type locality for species
 * †Poroblattina ohioensis – type locality for species
 * †Poroblattina richmondiana – type locality for species
 * †Poroblattina rotundata – type locality for species
 * †Posidonia
 * †Posidonia girtyi
 * †Praenucula
 * †Primiriopsis
 * †Primiriopsis punctulifera
 * †Primitia
 * †Primitia cincinnatiensis
 * †Primitia rudis
 * †Primitiella
 * †Primitiella claypolei
 * †Primitiella whitfieldi
 * †Probillingsites
 * †Probillingsites lebanonensis
 * Proboscina
 * †Proboscina auloporoides
 * †Proboscina frondosa
 * †Proctothylacocrinus
 * †Proctothylacocrinus esseri
 * †Proctothylacocrinus longus
 * †Productus
 * †Productus semireticulatua
 * Proetus concinnus reconstruction cropped.png †[[Proetus (trilobite)|Proetus]]
 * †Promopalaeaster
 * †Promopalaeaster granulosus
 * †Promopalaeaster wykoffi
 * †Promytilus
 * †Promytilus pottsvillensis – type locality for species
 * †Propora
 * †Propora conferta
 * †Propora eminula
 * †Prosserella
 * †Prosserella lucasi
 * †Prosserella subtransversa
 * †Protaraea
 * †Protaraea richmondensis
 * †Protarea
 * †Protathyris – tentative report
 * †Protobalanus
 * †Protobalanus spinicoronatus – type locality for species
 * †Protocycloceras
 * †Protocycloceras rushense
 * †Protokionoceras
 * †Protoleptostrophia
 * †Protoleptostrophia perplana
 * †Protosalvinia
 * †Protosalvinia arnoldii
 * †Protosalvinia ravenna
 * †Protoscolex
 * Reconstruction of Prototaxites loganii.tif †[[Prototaxites]]
 * †Prototaxites clevelandensis
 * †Pseudaviculopecten
 * †Pseudaviculopecten fasciculatus
 * †Pseudaviculopecten scabridus
 * †Pseudoactinodictyon
 * †Pseudoactinodictyon stearni
 * †Pseudoactinodictyon vagans
 * †Pseudoatrypa
 * †Pseudoatrypa devoniana
 * †Pseudobigalea
 * †Pseudobigalea crista
 * †Pseudocolpomya
 * †Pseudocolpomya miseneri
 * †Pseudolingula
 * †Pseudomonotis
 * †Pseudomonotis equistriata
 * †Pseudomonotis hawni
 * †Pseudomonotis millhorni – type locality for species
 * †Pseudomulceodens
 * †Pseudomulceodens cancellatus
 * †Pseudooneotodus
 * †Pseudooneotodus bicornis
 * †Pseudophorus
 * †Pseudophorus antiquus
 * †Pseudorthoceras
 * †Pseudorthoceras knoxense
 * †Pseudozygopleura
 * †Pseudozygopleura acuminata
 * †Pseudozygopleura angustata
 * †Pseudozygopleura assertonsoris
 * †Pseudozygopleura baltea – type locality for species
 * †Pseudozygopleura cirritus
 * †Pseudozygopleura contractus
 * †Pseudozygopleura deloi
 * †Pseudozygopleura eximia
 * †Pseudozygopleura funis
 * †Pseudozygopleura girtyi
 * †Pseudozygopleura gradatus
 * †Pseudozygopleura irrugata
 * †Pseudozygopleura kellettae – or unidentified comparable form
 * †Pseudozygopleura lanceolatus
 * †Pseudozygopleura limus
 * †Pseudozygopleura macra – or unidentified comparable form
 * †Pseudozygopleura mucronatus
 * †Pseudozygopleura multicostata – or unidentified comparable form
 * †Pseudozygopleura pagoda – or unidentified comparable form
 * †Pseudozygopleura palus – type locality for species
 * †Pseudozygopleura pandus
 * †Pseudozygopleura peoriense
 * †Pseudozygopleura pinquicula
 * †Pseudozygopleura plummeri – type locality for species
 * †Pseudozygopleura pluricostata
 * †Pseudozygopleura pugonis
 * †Pseudozygopleura pulchra
 * †Pseudozygopleura rectus
 * †Pseudozygopleura schucherti – or unidentified comparable form
 * †Pseudozygopleura scitula
 * †Pseudozygopleura scruposus
 * †Pseudozygopleura semicostata
 * †Pseudozygopleura sinuosior
 * †Pseudozygopleura subulatus
 * †Pseudozygopleura tenuivirga
 * †Pseudozygopleura variegata
 * †Psiloconcha
 * †Psiloconcha grandis
 * †Psiloconcha inornata
 * †Psiloconcha sinuata
 * †Pterinea
 * †Pterinea corrugatus
 * †Pterinea demissa
 * †Pterinopecten
 * †Pterinopecten undosus
 * †Pterochiton
 * †Pterochiton carbonarius
 * †Pterochiton spatulatus
 * †Pterospermella
 * †Pterospermella capitana
 * †Pterospermella latibalteus
 * †Pterospermella radiata
 * †Pterospermella solis
 * †Pterotheca
 * Pterygotus anglicus reconstruction.jpg †[[Pterygotus]]
 * †Pterygotus carmani
 * †Ptilodictya
 * †Ptomatis
 * †Ptomatis proteiforme
 * †Ptotosalvinia
 * †Ptotosalvinia furcata
 * †Ptychocarpus
 * †Ptychocrinus
 * †Ptychomphalina
 * †Ptychomphalina lucina
 * †Ptychomphalina regulata
 * †Ptychopteria
 * †Ptychopteria flabellum
 * †Ptychospirina
 * †Ptychospirina varians
 * †Ptyonius
 * †Ptyonius marshii – type locality for species
 * †Pugnax
 * †Pugnax utah
 * †Punctatisporites
 * †Punctatisporites aerarius
 * †Punctatisporites glaber
 * †Punctatisporites minutus
 * †Punctatisporites obesus
 * †Punctatisporties
 * †Punctatisporties minutus
 * †Punctatosporites
 * †Punctatosporites granifer
 * †Punctatosporites minutus
 * †Punctatosporites rotundus
 * †Punctospirifer
 * †Punctospirifer kentuckensis
 * †Pustula
 * †Pustula pertenuis
 * †Pustulisphaeridium
 * †Pustulisphaeridium levibrachium
 * †Pyanomya
 * †Pycnocrinus
 * †Pyrenomeous

Q

 * †Quadrijugator

R

 * †Rafinesquina
 * †Rafinesquina alternata
 * †Rafinesquina loxorhytis
 * †Rafinesquina ponderosa
 * †Rafinesquina squamula
 * †Raistrickia
 * †Raistrickia crinita
 * †Raistrickia srinita
 * †Ramphoprion
 * †Raphistoma
 * †Rasmussenoceras
 * †Reinschospora
 * †Reinschospora magnifica
 * †Renalcis
 * †Reptaria
 * †Reptaria stolonifera
 * †Reteocrinus
 * †Reteporina
 * †Reteporina striata
 * †Retichonetes
 * †Reticulatisporites
 * †Reticulatisporites muricatus
 * †Retispira
 * †Retispira fascireticulatus – type locality for species
 * †Retispira tenuilineata
 * †Retispira waverliensis
 * †Retrorsirostra
 * †Retrorsirostra carleyi
 * †Rhachicrinus
 * †Rhachicrinus wrighti
 * †Rhachiopteris
 * †Rhapanocrinus
 * †Rhegmaphyllum
 * †Rhegmaphyllum daytonensis
 * †Rhinidictya
 * †Rhinocaris
 * †Rhinocaris ehlersi
 * †Rhipidomella
 * †Rhipidomella pecosi
 * †Rhipidomella penelope – or unidentified comparable form
 * †Rhipidomella trigona
 * †Rhipidomella vanuxemi
 * †Rhipidothyris
 * Rhizocorallium mcr1.JPG †[[Rhizocorallium]]
 * †Rhombodictyon
 * †Rhombopora
 * †Rhombopora lepidodendroides
 * †Rhombotrypa
 * †Rhombotrypa subquadrata
 * †Rhopolonaria
 * †Rhopolonaria venosa
 * †Rhynchopora
 * †Rhynchotrema
 * †Rhynchotrema denatum
 * †Rhynchotrema dentatum
 * †Rhynchotreta
 * †Rhytimya
 * †Rhytimya compressa
 * †Rhytimya faberi
 * †Rhytimya lunulata
 * †Rhytimya oehana
 * †Rhytimya radiata
 * †Richmondoceras
 * †Richmondoceras brevicameratum
 * †Rizoceras
 * †Ropalonaria
 * †Royalella
 * †Royalella quadrolirata – type locality for species
 * †Royalella swallowiana – type locality for species
 * †Ruedemannia
 * †Ruedemannia trilix – type locality for species
 * †Rugomena
 * †Rugomena vetusta
 * †Rugosochonetes
 * RusophycusOrdovician.jpg †[[Rusophycus]]
 * †Rusophycus biloba

S

 * †Saccella
 * †Saccella parva
 * †Salpingostoma
 * †Salpingostoma richmondensis – tentative report
 * †Samaropsis
 * †Sanguinolites
 * †Sanguinolites cuneatus
 * †Sanguinolites hekitoensis – type locality for species
 * Sauropleura cropped.jpg †[[Sauropleura]] – type locality for genus
 * †Sauropleura pectinata – type locality for species
 * †Schellwienella
 * †Schistoceras
 * †Schizambon – tentative report
 * †Schizoblatta – type locality for genus
 * †Schizoblatta alutacea – type locality for species
 * †Schizocrania
 * †Schizocrania filosa
 * †Schizodus
 * †Schizodus acuminatus – type locality for species
 * †Schizodus affinis
 * †Schizodus appressus
 * †Schizodus chesterensis – or unidentified comparable form
 * †Schizodus curtus
 * †Schizodus subcircularis
 * †Schizodus wheeleri
 * †Schizolopha
 * †Schizophoria
 * †Schizophoria ferronensis
 * †Schizophoria impressa
 * †Schlotheimophyllum
 * †Schlotheimophyllum benedicti
 * †Schlotheimophyllum patellatum
 * †Schuchertella
 * †Schuchertella interstriata
 * †Schuchertoceras
 * †Scolithos
 * †Scolithos laxata
 * †Sedgwickia – tentative report
 * †Semicoscinium
 * †Semipora – tentative report
 * †Semipora ehlersi
 * †Septopora
 * †Septopora biserialis
 * †Septopora robusta
 * †Serpulites
 * †Serpulospira
 * †Serpulospira diversiformis
 * †Sevillia
 * †Sevillia sevillensis
 * †Sevillia trinucleata
 * †Shansiella
 * †Shansiella beckwithana
 * †Shansiella carbonaria
 * †Shansiella insecta
 * †Shideleroceras
 * Stanhope Tree - geograph.org.uk - 2531669.jpg †[[Sigillaria]]
 * †Sigillaria brardii
 * †Sigillaria elegans
 * †Sigillaria ficoides
 * †Sigillaria lacoei
 * †Sigillaria laurenciana
 * †Sigillaria mamillaris
 * †Sigillaria orbicularis
 * †Sigillaria pileata – type locality for species
 * †Sigillaria rugosa
 * †Sigillariostrobus
 * †Silfonocrinus
 * †Silfonocrinus siluricus
 * †Silicaster
 * †Silicaster esseri
 * †Similodonta – tentative report
 * †Sinuites
 * †Sinuites cancellatus
 * †Sinuites granistriatus
 * †Sinuites subcompressa
 * Solemya elarraichensis holotype.jpg [[Solemya]]
 * †Solemya radiata
 * †Solemya sharonensis – type locality for species
 * †Soleniscus
 * †Soleniscus aplatus – type locality for species
 * †Soleniscus klipparti
 * †Soleniscus primigenia
 * †Soleniscus primogenium
 * †Soleniscus regularis
 * †Soleniscus typicus
 * †Solenomorpha
 * †Solenomorpha lamborni
 * †Solisphaeridium
 * †Solisphaeridium astrum
 * †Solisphaeridium clavum
 * †Solisphaeridium folliculum
 * †Solisphaeridium rigispinosum
 * †Sowerbyella
 * †Sowerbyella rugosa
 * †Spatiopora
 * †Sphenolium
 * †Sphenophragmus
 * †Sphenophragmus nanus – or unidentified comparable form
 * Sphenophyllum miravallis cropped.jpg †[[Sphenophyllum]]
 * †Sphenophyllum majus
 * †Sphenophyllum oblongifolium
 * †Sphenopteris
 * †Sphenopteris elegans – or unidentified comparable form
 * †Sphenopteris minutisecta
 * †Sphenosphaera
 * †Sphenosphaera centervillensis – type locality for species
 * †Sphenosphaera fiscellostriata – type locality for species
 * †Sphenosphaera opertus – type locality for species
 * †Sphenosphaera recurvus – type locality for species
 * †Sphenothallus
 * †Spiloblattina
 * †Spiloblattina variegata – type locality for species
 * †Spinocyrtia
 * †Spinocyrtia euryteines – report made of unidentified related form or using admittedly obsolete nomenclature
 * †Spinosporites
 * †Spinosporites exiguus
 * †Spinulicosta
 * †Spinulicosta spinulicosta
 * †Spinyplatyceras
 * †Spinyplatyceras dumosum
 * Spirifer perlamosus pedunculate valve.jpg †[[Spirifer]]
 * †Spirifer opimus
 * †Spirifer pennatus
 * †Spiromphalus
 * †Spiromphalus pervius – type locality for species
 * Spiropteris
 * Spirorbis
 * †Spirorbis arkonensis
 * †Spirorbis planum
 * †Spiroscala
 * †Spiroscala solida
 * †Spongentactinella
 * †Spongentactinella veles
 * †Sporangites
 * †Sporangites huronensis
 * †Spyroceras
 * †Staufferoceras
 * †Stegocoelia
 * †Stegocoelia copei – or unidentified comparable form
 * †Stegops
 * †Stegops newberryi – type locality for species
 * †Stellinium
 * †Stellinium cristatum
 * †Stellinium inflatum
 * †Stellinium octoaster
 * †Stelodictyon
 * †Stereoaster
 * †Stereoaster squamosus
 * †Stereostylus
 * †Stereostylus amesensis
 * †Stereotoechus
 * †Stereotoechus typicus – or unidentified comparable form
 * Steth pair1 cropped.jpg †[[Stethacanthus]]
 * †Stethacanthus altonensis
 * †Stibarocrinus
 * †Stibarocrinus centervillensis
 * †Stictoporella
 * †Stictoporina
 * †Stictoporina granulifera
 * †Stigmatella
 * †Stigmatella catenulata
 * †Stigmatella crenulata
 * †Stigmatella dychei
 * Stomatopora
 * †Straparollus
 * †Straparollus hecale – or unidentified comparable form
 * †Straparollus rudis – or unidentified comparable form
 * †Strataster
 * †Strataster devonicus
 * †Streblochondria
 * †Streblopteria
 * †Streblopteria oklahomensis
 * †Streblotrypa
 * †Streblotrypa anomala
 * †Streblotrypa hamiltonensis
 * †Streptaster
 * †Streptaster vorticellatus
 * †Streptelasma
 * †Streptelasma divaricans
 * †Striatopora
 * †Striatopora flexuosa
 * †Striatopora intermittens
 * †Strobeus
 * †Strobeus brevis
 * †Strobeus immanis
 * †Strobeus intercalaris
 * †Strobeus paludinaeformis
 * †Stromatocerium
 * †Stromatocerium granulosum
 * †Stromatopora
 * †Strombodes
 * †Strombodes socialis
 * †Strophalosia
 * †Strophalosia truncata
 * †Stropheodonta
 * †Stropheodonta demissa
 * †Strophodonta
 * †Strophodonta demissa – report made of unidentified related form or using admittedly obsolete nomenclature
 * Strophomena costellata brachial.jpg †[[Strophomena]]
 * †Strophomena concordensis
 * †Strophomena erratica
 * †Strophomena extenuata
 * †Strophomena maysvillensis
 * †Strophomena neglecta
 * †Strophomena nutans
 * †Strophomena planoconvexa
 * †Strophomena planumbona
 * †Strophomena sulcata
 * †Strophostylus
 * †Sturgeonospira – type locality for genus
 * †Sturgeonospira tortula – type locality for species
 * †Stygetoblatta – type locality for genus
 * †Stygetoblatta latipennis – type locality for species
 * †Styliolina
 * †Styliolina fissurella
 * †Stylonema
 * †Stylonema robusta
 * †Subulites
 * †Subulites planilateralis – type locality for species
 * †Sulcoretepora
 * †Sulcoretepora deissi
 * †Sulcoretepora incisurata
 * †Synhomalonotus
 * †Syntomopterus
 * †Syntomopterus richardsoni
 * Syringoporid.jpg †[[Syringopora]] – tentative report
 * †Syringopora reteformis
 * †Syringostroma
 * †Syringostroma cylindricum
 * †Syringostroma densum
 * †Syringostroma nodulatum
 * †Syringostroma pustulosum
 * †Syringothyris
 * †Syringothyris bedfordensis
 * †Syscioblatta
 * †Syscioblatta anomala – type locality for species
 * †Syscioblatta minor – type locality for species
 * †Syscioblatta misera – type locality for species
 * †Syscioblatta obscura – type locality for species
 * †Syscioblatta steubenvilleana – type locality for species
 * †Sysciophlebia
 * †Sysciophlebia acutipennis – type locality for species
 * †Sysciophlebia adumbrata – type locality for species
 * †Sysciophlebia affinis – type locality for species
 * †Sysciophlebia balteata
 * †Sysciophlebia benedicta – type locality for species
 * †Sysciophlebia hybrida – type locality for species
 * †Sysciophlebia nana – type locality for species
 * †Sysciophlebia obtusa – type locality for species
 * †Sysciophlebia picta – type locality for species
 * †Sysciophlebia rotundata – type locality for species
 * †Sysciophlebia schucherti – type locality for species
 * †Sysciophlebia scudderi – type locality for species
 * †Sysciophlebia variegata – type locality for species
 * †Sysciophlebia whitei – type locality for species

T

 * †Taeniaster
 * †Taeniaster elegans
 * †Taeniopteris
 * †Taeniopteris lescuriana
 * †Taeniopteris newberriana
 * †Tamiobatis
 * †Tamiobatis vetustus
 * †Tanaocrinus
 * †Tasmanites
 * †Technophora
 * †Technophorus – type locality for genus
 * †Technophorus faberi – type locality for species
 * †Teichichnus
 * †Temnocheilus
 * †Temnocheilus forbesianus
 * Tentaculitid041011.jpg †[[Tentaculites]]
 * †Tentaculites bellulus
 * †Tentaculites gracilistriatus
 * †Tetradium
 * †Tetranota
 * †Tetranota bidorsata
 * †Tetrentactinia
 * †Tetrentactinia barysphaera
 * †Tetrentactinia gracilispinosa
 * †Tetrentactinia quadrispinosa
 * †Tetrentactinia somphosphaera
 * †Tetrentactinia somphozona
 * †Tetrentactinia spongacea
 * †Tetrentactinia teuchestes
 * †Thamnoptychia
 * †Thamnoptychia alpenensis
 * †Thamnoptychia labyrinthica
 * †Thamnoptychia minuitissima
 * †Thamnoptychia projecta – tentative report
 * †Thamnoptychia silicensis
 * †Thymospora
 * †Thymospora obscura
 * †Thymospora pseudothiessenii
 * †Tirocrinus
 * †Tirocrinus trochos
 * †Tomoceras
 * †Tomoceras gilliana – or unidentified comparable form
 * †Torispora
 * †Torispora securis
 * †Tornacia
 * †Tornacia stela
 * †Tornoceras
 * †Tornoceras uniagnulare
 * †Tornoceras uniangulare
 * †Toryniferella
 * †Trachydomia
 * †Tremanotus
 * †Trematis
 * †Trematis millepunctata
 * †Trematis millepuntata
 * †Trematis reticularis
 * †Trematopora
 * †Trepospira
 * †Trepospira illinoisensis
 * Proteoceratidae - Treptoceras duseri cropped.jpg †[[Treptoceras]]
 * †Treptoceras byrnesi
 * †Treptoceras cincinnatiensis
 * †Treptoceras duseri
 * †Treptoceras fosteri
 * †Triarthrus
 * †Triendoceras – tentative report
 * †Triendoceras davisi
 * †Trigonoglossa
 * †Trigonoglossa nebrascensis
 * †Trigrammaria
 * †Trilonche
 * †Trilonche cancellicula
 * †Trilonche prolata
 * †Trimerella
 * †Triquitrites
 * †Triquitrites additus
 * †Triquitrites bransonii
 * †Triquitrites crassus
 * †Triquitrites minutus
 * †Triquitrites sculptilis
 * †Triquitrites spinosus
 * †Triquitrites subspinosus – or unidentified comparable form
 * †Triquitrites tribullatus
 * †Trocholites
 * †Trochonema
 * †Trochonemopsis
 * †Trochonemopsis meekanum
 * †Troedssonoceras
 * †Tropidodiscus
 * †Tropidodiscus vesculilineatus – type locality for species
 * †Tropidoleptus
 * †Tropidoleptus carinatus
 * †Truncatiramus – now regarded as a jr. synonym of Erettopterus
 * †Truncatiramus perryensis
 * Trypetesa
 * †Trypetesa caveata
 * †Trypherocrinus
 * †Trypherocrinus brassfieldensis
 * †Tuberculatosporites
 * †Tuberculatosporites robustus
 * Tuditanus1DB.jpg †[[Tuditanus]] – type locality for genus
 * †Tuditanus punctulatus – type locality for species
 * †Turbocrinus
 * †Turbocrinus paunctum
 * †Turbonopsis
 * †Turbonopsis shumardii
 * †Typanocrinus
 * †Typanocrinus strombos

U

 * †Ulrichia
 * †Ulrichia nodosa
 * †Umbotropis
 * †Umbotropis filitexta – type locality for species
 * †Uncinisphaera
 * †Uncinisphaera lappa
 * †Unellium
 * †Unellium ampullium
 * †Unellium elongatum
 * †Unellium oscitans
 * †Unklesbayella – type locality for genus
 * †Unklesbayella geinitzi
 * Urasterella asperula.jpg †[[Urasterella]]
 * †Urasterella grandis

V

 * †Vanuxemia
 * †Vanuxemia waynesvillensis – type locality for species
 * †Vaupelia
 * †Vermiforichnus
 * †Vermiforichnus clarkei – or unidentified comparable form
 * †Verrucosisporites
 * †Verrucosisporites cerosus
 * †Verrucosisporites donarii
 * †Verrucosisporites henshawensis
 * †Verrucosisporites microtuberosus
 * †Verrucosisporites microtuerosus
 * †Verrucosisporites verrucosus
 * †Veryhachium
 * †Veryhachium roscidum
 * †Veryhachium trispinosoides
 * †Vesicaspora
 * †Vesicaspora wilsonii
 * †Vestispora
 * †Vestispora fenestrata
 * †Vestispora laevigata
 * †Vinella
 * †Vinlandostrophia
 * †Vinlandostrophia acutilirata
 * †Vinlandostrophia ponderosa
 * †Vorticina
 * †Vorticina cyrtolites

W

 * †Waagenella
 * †Waagenella crassus
 * Walchia piniformis.jpg †[[Walchia]]
 * †Walchiostrobus
 * †Walliserodus
 * †Walliserodus sancticlairi
 * †Welleria – tentative report
 * †Westonoceras
 * †Whidbornella
 * †Whiteavesia
 * †Whitfieldella
 * †Whitfieldoceras
 * †Wilkingia
 * †Wilkingia andrewsi
 * †Wilkingia maxvillensis
 * †Wilkingia terminale
 * †Wilsonites
 * †Wilsonites vesicatus
 * †Worthenia
 * †Worthenia parvula
 * †Worthenia speciosa
 * †Worthenia strigillata
 * †Worthenia tabulata
 * †Wurmiella
 * †Wurmiella excavata

X

 * †Xenocrinus
 * Xylobius.jpg †[[Xyloiulus]]
 * †Xyloiulus bairdi – type locality for species
 * †Xysmacrinus
 * †Xysmacrinus greenensis

Z

 * †Zascinaspis
 * †Zirocrinus
 * †Zirocrinus litos
 * †Zittelloceras
 * †Zonalosporites
 * †Zonalosporites ellipticus
 * ZoophycosMississippian.jpg †[[Zoophycos]]
 * †Zygocycloides
 * †Zygocycloides magnus
 * †Zygospira
 * †Zygospira cincinnatiensis
 * †Zygospira modesta