# List of the Paleozoic life of Arkansas

This list of the Paleozoic life of Arkansas contains the various prehistoric life-forms whose fossilized remains have been reported from within the US state of Arkansas and are between 541 and 252.17 million years of age.

## A

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* G
* H
* I
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* M
* N
* O
* P
* Q
* R
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* U
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* X
* Y
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* †Adnatoceras
** †Adnatoceras alaskense
* †Ahrensisporites
** †Ahrensisporites guerickei
* †Amphiscapha
** †Amphiscapha intermedius
* †Amphissites
** †Amphissites rugosus
* †Amplexizaphrentis
** †Amplexizaphrentis maneri – type locality for species
* †Amplexizaphretis
** †Amplexizaphretis maneri – type locality for species
* †Amplexus
* †Ananaspis
* †Anchicrinus
** †Anchicrinus planulatus
* †Ancillotoechia
** †Ancillotoechia marginata
* †Angyomphalus
** †Angyomphalus desultoria – type locality for species
** †Angyomphalus discus
* †Anomphalomorpha – report made of unidentified related form or using admittedly obsolete nomenclature
* †Anthracoceras
** †Anthracoceras paucilobum
* †Anthracomartus
** †Anthracomartus trilobitus – type locality for species
* †Anthracospirifer
* †Antiquatonia
* †Antirhynchonella
** †Antirhynchonella thomasi
* †Aphelaeceras
** †Aphelaeceras arkansanum – type locality for species
* †Aphralysia – tentative report
* †Apiculatasporites
** †Apiculatasporites variocorneus
* †Apotocardium
** †Apotocardium peculiare – type locality for species
** †Apotocardium polymitarium – type locality for species
** †Apotocardium snideri – tentative report
* †Arcanoceras
** †Arcanoceras furnishi – type locality for species
* †Archaeocidaris
* Archaeolithophyllum – tentative report
* †Archimastax
** †Archimastax americanus – type locality for species
* Fossils of the Carboniferous-Permian bryozoan Archimedes †Archimedes
* †Archimylacris
** †Archimylacris venusta – type locality for species
* †Arkacrinus
** †Arkacrinus dubius
* †Arkanites
** †Arkanites relictus
* †Arkoceras
** †Arkoceras exiguum
* †Asketomorpha – type locality for genus
** †Asketomorpha grandis – type locality for species
* †Asphaltina
* †Astartella
** †Astartella concentrica – or unidentified comparable form
* †Athyris
* †Atrypa
* †Atrypina
** †Atrypina erugata
* Mold fossil of a shell of the Early Devonian-Late Triassic bivalve Aviculopecten †Aviculopecten
** †Aviculopecten inspeciosus
** †Aviculopecten jennyi
** †Aviculopecten morrowensis
** †Aviculopecten squamula
* † Avonia
** †Avonia honeycreekensis
* †Axinolobus
** †Axinolobus modulus – type locality for species

## B

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* †Bactrites
** †Bactrites carbonarius
** †Bactrites gaitherensis
** †Bactrites redactus
** †Bactrites smithianus
* †Bactritimimus
** †Bactritimimus girtyi – type locality for species
** †Bactritimimus ulrichi – type locality for species
* †Baiosoma
** †Baiosoma cucullata – type locality for species
* Bairdia
** †Bairdia girtyi
* †Barytichisma
** †Barytichisma clubinei
** †Barytichisma ozarkana
* †Baschkirites
** †Baschkirites librovitchi
* †Beecheria
* †Bellerophon
** †Bellerophon welshi
* †Bisatoceras
** †Bisatoceras secundum
* †Bistrialites
** †Bistrialites bicostatus – type locality for species
* †Boesites
** †Boesites scotti
* †Borestus
* †Boucotides
** †Boucotides barrandei
* †Brachycycloceras
** †Brachycycloceras washingtonense – type locality for species
* †Brachymimulus
** †Brachymimulus americanus
** †Brachymimulus elongatus
* †Brachythyris
* †Bradyphyllum
** †Bradyphyllum lesliense – type locality for species
* †Branneroceras
** †Branneroceras branneri
* †Bridgeites
** †Bridgeites planidorsalis – type locality for species
* †Buttsia
** †Buttsia drabensis
* †Buxtonia

## C

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* †Cancelloceras
** †Cancelloceras hunstvillense – type locality for species
** †Cancelloceras huntsvillense – type locality for species
* †Caneyella
** †Caneyella peculiaris
** †Caneyella percostata
** †Caneyella wapanuckensis – or unidentified comparable form
* †Caninostrotion
** †Caninostrotion variabilis
* †Carcharopsis
** †Carcharopsis wortheni
* †Cardiomorpha – tentative report
** †Cardiomorpha inflata
* †Caryocrinites
* †Cavellina
* †Cavusgnathus
* †Centrotarphyceras
** †Centrotarphyceras yellvillense
* †Ceratopea
** †Ceratopea unguis
* †Cheilocephalus
** †Cheilocephalus brachyops
* Fossil of the Cambrian-Middle Devonian trilobite Cheirurus †Cheirurus
** †Cheirurus phollikodes – type locality for species
** †Cheirurus prolixus – type locality for species
* †Choctawites
** †Choctawites choctawensis
* †Chonetes
* †Clathrospira
** †Clathrospira virguncula
* †Cleiothyridina
* †Cliffia
** †Cliffia lataegenae
* †Cluthoceras
** †Cluthoceras glicki – type locality for species
* †Clytoceras
** †Clytoceras capax
* †Coelogasteroceras
** †Coelogasteroceras gracile
* †Comanchia
** †Comanchia amplooculata
* Fossilized shell of the Late Devonian-Permian brachiopod Composita †Composita
* †Compsonema
* †Convolutispora
* †Copiceras
** †Copiceras erectum
* †Cornuproetus
** †Cornuproetus kyphora – type locality for species
* †Cranaena
* †Crassispora
** †Crassispora kosankei
* †Cravenoceras
** †Cravenoceras lineolatum – type locality for species
* †Criboconcha
* †Cristatisporites
** †Cristatisporites connexus
** †Cristatisporites indignabundus
* †Cromyocrinus
** †Cromyocrinus grandis – type locality for species
* †Crurithyris
** †Crurithyris parva
* †Ctenobactrites
** †Ctenobactrites lesliensis – type locality for species
* †Cupulocorona
** †Cupulocorona gemmiformis
** †Cupulocorona osgoodensis
* †Cyclogranisporites
* †Cycloplectoceras
** †Cycloplectoceras funatum
** †Cycloplectoceras miseri
* †Cymoceras
** †Cymoceras cracens
* †Cymostrophia – report made of unidentified related form or using admittedly obsolete nomenclature
* †Cypricardella
** †Cypricardella subalata
* †Cypricardinia – tentative report
** †Cypricardinia fayettevillensis
* †Cyrtina

## D

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* †Dalmanites – type locality for genus
** †Dalmanites bassleri
** †Dalmanites howelli
** †Dalmanites ptyktorhion – type locality for species
* †Decoroproetus
** †Decoroproetus anaglyptus – type locality for species
** †Decoroproetus corycoeus
* Life restoration of two species of the Silurian trilobite Deiphon †Deiphon
** †Deiphon longifrons
* †Dellea
** †Dellea suada
* †Delops
* †Densosporites
** †Densosporites annulatus
** †Densosporites irregularis
** †Densosporites sphaerotriangularis
** †Densosporites triangularis
* †Dentoceras
** †Dentoceras belemnitiforme – type locality for species
* †Desmoinesia
* †Diaboloceras
** †Diaboloceras neumeieri – type locality for species
** †Diaboloceras varicostatum
* Fossil and mold of the Late Ordovician-Silurian trilobite Diacalymene †Diacalymene
** †Diacalymene altirostris
* †Diacamaropsis
** †Diacamaropsis parva
* †Diaphragmus
* †Dicamaropsis
** †Dicamaropsis parva
* †Dicoelosia
** †Dicoelosia bilobella
* †Dielasma
* †Dinocycloceras
** †Dinocycloceras ballianum – or unidentified comparable form
** †Dinocycloceras prolixum
* †Diphuicrinus
** †Diphuicrinus croneisi
* †Dolerorthis – tentative report
** †Dolerorthis nanella
* †Dolorthoceras
** †Dolorthoceras caneyanum – or unidentified comparable form
** †Dolorthoceras incisum – type locality for species
** †Dolorthoceras tenuifilosum – type locality for species

## E

* A
* B
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* D
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* F
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* I
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* M
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* †Echinaria
* †Echinoconchus
* †Economolopsis – type locality for genus
** †Economolopsis gordoni – type locality for species
* †Ectogrammysia – type locality for genus
** †Ectogrammysia crassatis – type locality for species
* †Edmondia
** †Edmondia equilateralis
* †Edmooroceras
** †Edmooroceras plummeri
* Fossil of the Middle Ordovician-Early Devonian trilobite Encrinurus †Encrinurus
** †Encrinurus egani
* †Endolobus
** †Endolobus clorensis
* †Eoasianites
** †Eoasianites smithwickensis
* †Eophacops
** †Eophacops fontana – type locality for species
* †Eopteria
** †Eopteria richardsoni
* †Eospirifer
** †Eospirifer acutolineatus
* †Eowellerites
** †Eowellerites discoidalis – type locality for species
** †Eowellerites moorei – or unidentified comparable form
* †Ephippioceras
** †Ephippioceras ferratum
* †Epistroboceras
** †Epistroboceras lesliense – type locality for species
** †Epistroboceras mangeri – type locality for species
** †Epistroboceras pitkinense – type locality for species
* Fossilized calyx of the Silurian-Middle Devonian crinoid ("sea lily") Eucalyptocrinites †Eucalyptocrinites
* †Euchondria
* †Euconospira
** †Euconospira desereti – or unidentified related form
** †Euconospira disjuncta
* †Euloxoceras
** †Euloxoceras angustius – type locality for species
** †Euloxoceras greenei
* †Eumetria
* †Eumorphoceras
** †Eumorphoceras bisulcatum
** †Eumorphoceras milleri – type locality for species
** †Eumorphoceras ornatissimum – or unidentified comparable form
* Fossilized shell of the Silurian-Permian sea snail Euomphalus †Euomphalus
** †Euomphalus konobasis – type locality for species
** †Euomphalus variabilis – type locality for species
* †Eupachycrinus
** †Eupachycrinus magister – or unidentified comparable form
* †Euphemites
** †Euphemites chesterensis – type locality for species
** †Euphemites whirligigi – type locality for species

## F

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* †Fayettevillea
** †Fayettevillea planorbis – type locality for species
* †Florinites
** †Florinites similis
** †Florinites volans

## G

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* †Garwoodia – tentative report
* †Gastrioceras
** †Gastrioceras adaense
** †Gastrioceras fittsi
** †Gastrioceras formosum – type locality for species
* Fossil of the bore-hole ichnogenus Gastrochaenolites (G) Gastrochaenolites
** †Gastrochaenolites anauchen
* †Gattendorfia
* †Geisina – tentative report
** †Geisina retiferiformis
* †Girtyoceras
** †Girtyoceras welleri – type locality for species
* †Girtyspira
** †Girtyspira microspirula – type locality for species
* †Girvanella
* †Glabrocingulum
** †Glabrocingulum binodosum
** †Glabrocingulum coronulum – type locality for species
** †Glabrocingulum parasolum – type locality for species
** †Glabrocingulum parvanodum – type locality for species
** †Glabrocingulum quadrigatum
* †Glaphyrites
** †Glaphyrites depressus
** †Glaphyrites fayettevillae – type locality for species
** †Glaphyrites morrowensis
* †Globozyga
** †Globozyga mediocris – type locality for species
* †Glyphiolobus
* Fossil of the Silurian trilobite Glyptambon †Glyptambon – type locality for genus
** †Glyptambon verrucosus
* †Glyptopleura
** †Glyptopleura angulata
** †Glyptopleura inopinata
* †Gnathodus
** †Gnathodus texanus
* †Goniatites
** †Goniatites crenistria – or unidentified related form
** †Goniatites granosus
** †Goniatites multiliratus
* †Gordonites
** †Gordonites filifer
** †Gordonites matheri
* †Granulatisporites
** †Granulatisporites adnatoides
* †Graphiadactyllis
** †Graphiadactyllis arkansana
** †Graphiadactyllis fayettevillensis

## H

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* †Haplistion
** †Haplistion sphaericum
* †Harpidella
** †Harpidella butorus – type locality for species
** †Harpidella spinulocervix
* †Healdia
* †Hematites
** †Hematites barbarae
* †Holocystites
** †Holocystites alternatus
* †Homoceratoides
** †Homoceratoides cracens
* †Homoeospirella
** †Homoeospirella costatula
** †Homoeospirella pygmaea
* †Hormotoma
** †Hormotoma anna
** †Hormotoma artemesia – type locality for species
* †Housia
** †Housia vacuna
* †Howellella
** †Howellella splendens
* †Hudsonoceras
** †Hudsonoceras moorei
* †Hustedia
* †Hydreionocrinus
* †Hypotetragona – tentative report

## I

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* †Imitoceras
** †Imitoceras sinuatum – type locality for species
* †Imoella – type locality for genus
** †Imoella obscura – type locality for species
* †Imogloba
** †Imogloba gandyensis
* †Imonautilus – type locality for genus
** †Imonautilus meeki – type locality for species
* †Incisurella
** †Incisurella prima
* †Inflatia
** †Inflatia clydensis
* †Irvingella
** †Irvingella major

## J

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* †Janthimorpha – report made of unidentified related form or using admittedly obsolete nomenclature
* †Jasperoceras
** †Jasperoceras costatum

## K

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* †Kaskia
** †Kaskia chesterensis
* †Kazakhstania – tentative report
* †Kindbladia
** †Kindbladia wichitaensis
* †Kinkaidia
** †Kinkaidia trigonalis
* †Kirkbya
** †Kirkbya reflexa
* †Kirkbyella
** †Kirkbyella quadrata
* †Knightoceras
** †Knightoceras oxylobatum – type locality for species
** †Knightoceras patulum
* †Knoxisporites
** †Knoxisporites triradiatus
* †Kozlowskiellina
** †Kozlowskiellina vaningeni
* †Krotovia

## L

* A
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* †Laevigatosporites
** †Laevigatosporites desmoinesensis
** †Laevigatosporites vulgaris
* †Lasanocrinus
** †Lasanocrinus strigosus
* †Leangella
** †Leangella dissiticostella
* †Leonardophyllum
** †Leonardophyllum arkansanum
* †Lepdioproetus
** †Lepdioproetus xeo – type locality for species
* †Leptaena
* †Leptagonia
* †Leptocyrtoceras
** †Leptocyrtoceras curvatum
** †Leptocyrtoceras powellense
* †Leptodesma
* †Limipecten
* †Lingula
* †Linoproductus
* †Liroceras – tentative report
* †Lissatrypa
** †Lissatrypa clairensis
* †Lissostrophia
* †Lophamplexus – tentative report
* †Lophophyllidium
** †Lophophyllidium imoense – type locality for species
* †Lophotriletes
** †Lophotriletes microsaetosus
* †Lusitanites
** †Lusitanites subcircularis
* †Lycospora
** †Lycospora micropapillata
** †Lycospora pellucida
* †Lygdozoon – type locality for genus
** †Lygdozoon anoplos – type locality for species
** †Lygdozoon arkansanum
** †Lygdozoon collatum – type locality for species
* †Lysocystites – or unidentified related form

## M

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* †Macropotamorhynchus
** †Macropotamorhynchus chouteauensis
** †Macropotamorhynchus tuta
* †Macrostylocrinus
* †Magnumbonella
* †Mammoides
* †Mariceras
* †Marmolatella
** †Marmolatella imoensis – type locality for species
** †Marmolatella macgordoni – type locality for species
* †Meekospira
** †Meekospira minuta
* †Megaglossoceras
** †Megaglossoceras glicki – type locality for species
* †Megapronorites
** †Megapronorites baconi
* †Meristina
** †Meristina clairensis
* Fossilized shell of the Carboniferous-Permian nautiloid cephalopod Metacoceras †Metacoceras
* †Metacromyocrinus
** †Metacromyocrinus gillumi
* †Metadimorphoceras
** †Metadimorphoceras subdivisum
* †Metutharocrinus
** †Metutharocrinus cockei – type locality for species
* †Michelinia
** †Michelinia macerimuris – type locality for species
** †Michelinia meekana
** †Michelinia tenuicula
* †Michelinoceras
** †Michelinoceras wapanuckense
* †Microcheilinella – tentative report
* †Mitorthoceras
** †Mitorthoceras crebriliratum
** †Mitorthoceras girtyi – type locality for species
** †Mitorthoceras perfilosum
** †Mitorthoceras yellvillense – type locality for species
* †Monoceratina
* †Mooreoceras
** †Mooreoceras wedingtonianum – type locality for species
* †Mourlonia
** †Mourlonia lativittata
* †Muensteroceras
** †Muensteroceras arkansanum – type locality for species
** †Muensteroceras collinsoni – type locality for species
** †Muensteroceras pisiforme – type locality for species
* †Multithecopora
* †Myalina
** †Myalina parallela – or unidentified comparable form

## N

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* †Naiadites – tentative report
* Fossilized shell of the Early Devonian – Triassic sea snail Naticopsis †Naticopsis
** †Naticopsis clinovata – or unidentified comparable form
** †Naticopsis genevievensis
* †Neochonetes
* †Neoglyphioceras
** †Neoglyphioceras caneyanum
** †Neoglyphioceras crebriliratum
* †Nostocites
* †Nucleospira
** †Nucleospira raritas
* †Nuculavus
** †Nuculavus okawensis
* †Nuculopsis
** †Nuculopsis shumardana

## O

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* †Ogygoceras
** †Ogygoceras gracile
* †Onychotreta
** †Onychotreta lenta
** †Onychotreta mesleri
** †Onychotreta miseri
** †Onychotreta multiplicata
** †Onychotreta plicata
* †Orbiculoidea
* †Orospira
** †Orospira elegantula
* †Orthobairdia
** †Orthobairdia cestriensis
* †Orthonychia
** †Orthonychia compressum
** †Orthonychia ungula
* †Orthostrophella
** †Orthostrophella clairensis
* †Orthotetes
* †Ortonella – tentative report
** †Ortonella kershopensis
* †Ovatia
* †Oxoplecia
** †Oxoplecia infrequens
* †Ozarcus – type locality for genus
** †Ozarcus mapesae – type locality for species

## P

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* †Pachylyroceras
** †Pachylyroceras cloudi
** †Pachylyroceras newsomi
* †Paladin
** †Paladin mucronatus
* †Palaeacis
** †Palaeacis carinata
* †Palaeocapulus
** †Palaeocapulus undata
* †Palaeoneilo
** †Palaeoneilo sera
* †Paleoconus
** †Paleoconus bakeri – type locality for species
* †Paleyoldia
** †Paleyoldia angustia – type locality for species
** †Paleyoldia bruta – type locality for species
* †Palmerocrinus
** †Palmerocrinus kesslerensis – type locality for species
* †Paracravenoceras
** †Paracravenoceras ozarkense – type locality for species
* †Paracromyocrinus
** †Paracromyocrinus oklahomensis
* †Paradimorphoceras
* †Paralegoceras
** †Paralegoceras iowense
** †Paralegoceras texanum
* †Parallelodon
** †Parallelodon cancellosus – or unidentified comparable form
* †Paramphicrinus
** †Paramphicrinus magnus – type locality for species
* †Paraparchites – tentative report
** †Paraparchites cyclopeus
* †Parastrophinella
** †Parastrophinella lepida
* †Parvaxon
** †Parvaxon minutum
* †Patellilabia
** †Patellilabia laevigata
** †Patellilabia rhombadella – type locality for species
** †Patellilabia sulcata – type locality for species
* Fossilized theca of the Carboniferous blastoid echinoderm ("sea bud") Pentremites †Pentremites
* †Pericyclus
* †Perigrammoceras
* †Perimestocrinus
** †Perimestocrinus teneris
* †Peripetoceras
** †Peripetoceras ozarkense – type locality for species
* †Permophorus
* †Phaneroceras
** †Phaneroceras compressum
** †Phaneroceras kesslerense – type locality for species
* †Pharkidonotus
* †Phestia
** †Phestia corrugata – type locality for species
** †Phestia obtusa – type locality for species
** †Phestia wortheni – type locality for species
* †Phricodothyris
* †Pilosisporites
** †Pilosisporites williamsii
* †Pionoceras
** †Pionoceras smithvillense
* †Placotriplesia
** †Placotriplesia juvenis
** †Placotriplesia praecipta
* Fossilized shell of the Silurian-Early Triassic sea snail Platyceras †Platyceras
** †Platyceras latum
** †Platyceras oxynotum – type locality for species
* †Plectatrypa
** †Plectatrypa arctoimbricata
* †Plectodonta – tentative report
* †Plicochonetes
* †Plicocyrtia
** †Plicocyrtia arkansana
* †Polidevcia
** †Polidevcia stevensiana
* †Posidonia
** †Posidonia nasuta
* †Productina
** †Productina sampsoni
* †Productus
* Restoration of the Silurian trilobite Proetus †Proetus
** †Proetus vaningeni
* †Prolecanites
** †Prolecanites lyoni – or unidentified comparable form
* †Proshumardites
** †Proshumardites morrowanus
* †Prospira
** †Prospira latior
* †Prothyris
** †Prothyris crista – type locality for species
** †Prothyris soleniformis – or unidentified comparable form
* †Protocycloceras
** †Protocycloceras arkansaense
** †Protocycloceras smithvillense
* †Pseudagnostus
** †Pseudagnostus communis
* †Pseudokingstonia
** †Pseudokingstonia exotica
* †Pseudopronorites
** †Pseudopronorites arkansiensis
** †Pseudopronorites quinni
* †Pseudorthoceras
** †Pseudorthoceras knoxense
** †Pseudorthoceras stonense – type locality for species
* †Pseudozygopleura
* †Pterocephalia
** †Pterocephalia sanctisabae
* †Ptychomphalina
** †Ptychomphalina magna – type locality for species
* †Punctospirifer
* †Pycnoceras
** †Pycnoceras clausum
* †Pygmaeoceras
** †Pygmaeoceras solidum

## Q

* A
* B
* C
* D
* E
* F
* G
* H
* I
* J
* K
* L
* M
* N
* O
* P
* Q
* R
* S
* T
* U
* V
* W
* X
* Y
* Z
* †Quinnites
** †Quinnites henbesti
** †Quinnites textum

## R

* A
* B
* C
* D
* E
* F
* G
* H
* I
* J
* K
* L
* M
* N
* O
* P
* Q
* R
* S
* T
* U
* V
* W
* X
* Y
* Z
* †Radnoria
* †Ramosites
* †Raphiophorus
** †Raphiophorus niagarensis
* †Rayonnoceras
** †Rayonnoceras eccentricum – type locality for species
** †Rayonnoceras fayettevillense
** †Rayonnoceras irregulare – or unidentified comparable form
** †Rayonnoceras nobile – or unidentified comparable form
** †Rayonnoceras protentum – type locality for species
** †Rayonnoceras solidiforme
** †Rayonnoceras vaughanianum
* †Rectangulina
* †Resserella
* †Reticulariina
* †Reticuloceras
** †Reticuloceras tiro
** †Reticuloceras wainwright
** †Reticuloceras wainwrighti
* †Reticycloceras
** †Reticycloceras croneisi – type locality for species
** †Reticycloceras girtyi – type locality for species
** †Reticycloceras peytonense – type locality for species
** †Reticycloceras sequoyahense
* †Retispira
** †Retispira cincta
** †Retispira ordinata – or unidentified related form
** †Retispira yochelsoni – type locality for species
* †Retites
** †Retites semiretia
* †Reviya
** †Reviya planus – or unidentified related form
* †Rhipidomella
* †Rhynchopora
* †Rhytiophora
** †Rhytiophora blairi
* †Richardsonites
** †Richardsonites richardsonianum
** †Richardsonites richardsonianus
* †Roundyella
** †Roundyella simplex

## S

* A
* B
* C
* D
* E
* F
* G
* H
* I
* J
* K
* L
* M
* N
* O
* P
* Q
* R
* S
* T
* U
* V
* W
* X
* Y
* Z
* †Sandia
* †Sanguinolites
** †Sanguinolites simulans – tentative report
* †Sansabella
** †Sansabella fayettevillensis
** †Sansabella reticulata
* †Savitrisporites
** †Savitrisporites nux
* †Schartymites
** †Schartymites paynei
* †Schellwienella
* †Schizodus
** †Schizodus chesterensis
* †Schizophoria
* †Schuchertella
* †Schulzospora
** †Schulzospora rara
* †Schumardella
** †Schumardella obsolecens
* †Sedenticellula
* †Sedgwickia
* †Seminolites
* †Septatrypa
** †Septatrypa havliceki
* †Septimyalina
** †Septimyalina perattenuata – or unidentified comparable form
* †Serenida
** †Serenida seminalis
* †Shaleria
* †Solenochilus
** †Solenochilus floweri – type locality for species
** †Solenochilus peculiare – or unidentified comparable form
* †Solenomorpha
** †Solenomorpha nitida
* †Spathelopsis – type locality for genus
** †Spathelopsis browni – type locality for species
* Fossil of the Middle Ordovician-Silurian trilobite Sphaerexochus †Sphaerexochus
** †Sphaerexochus glaber – type locality for species
* †Sphenotus
** †Sphenotus branneri
** †Sphenotus dubius
** †Sphenotus meslerianus
** †Sphenotus pisinnus – type locality for species
** †Sphenotus washingtonensis
* Fossilized shell of the Late Ordovician-Late Triassic brachiopod Spirifer †Spirifer
* †Spiriferellina
* †Staurocephalus
** †Staurocephalus lagena – type locality for species
** †Staurocephalus oarion – type locality for species
* †Stearoceras
** †Stearoceras gibbosum – or unidentified related form
** †Stearoceras smithi – type locality for species
* †Stenoglaphyrites
** †Stenoglaphyrites involutus – type locality for species
** †Stenoglaphyrites miseri – type locality for species
* †Stenopronorites
* †Sthenarocalymene
** †Sthenarocalymene scutula – type locality for species
* Fossil preserved in situ of a Carboniferous tree-like club moss relative with attached Stigmaria rhizome system †Stigmaria
** †Stigmaria wedingtonensis
* †Stioderma
** †Stioderma hadra – type locality for species
* †Streptis
** †Streptis glomerata
* †Streptorhynchus
* †Strobeus
* †Stroboceras
** †Stroboceras gordoni – type locality for species
** †Stroboceras sulcatum – or unidentified comparable form
* †Sudeticeras
* †Sulcella
* †Sulcogirtyoceras
** †Sulcogirtyoceras jasperense – type locality for species
** †Sulcogirtyoceras limatum
* †Sutherlandia
* †Syngastrioceras
** †Syngastrioceras globosum
** †Syngastrioceras oblatum
** †Syngastrioceras scotti
* †Syntrophopsis
** †Syntrophopsis grandis – type locality for species

## T

* A
* B
* C
* D
* E
* F
* G
* H
* I
* J
* K
* L
* M
* N
* O
* P
* Q
* R
* S
* T
* U
* V
* W
* X
* Y
* Z
* †Tectamichelina – type locality for genus
** †Tectamichelina mangeri – type locality for species
* †Teiichispira
** †Teiichispira odenvillensis
* †Tesuquea
* †Tetracamera
* †Tetratylis – tentative report
* †Tetratylus – tentative report
* †Torynifer
* †Trepspira
** †Trepspira tentative report type locality for species – informal
* †Triboloceras – tentative report
* †Tripteroceroides – tentative report
* Fossils of the bore-hole ichnogenus Trypanites Trypanites
* †Tylonautilus
** †Tylonautilus gratiosus

## U

* A
* B
* C
* D
* E
* F
* G
* H
* I
* J
* K
* L
* M
* N
* O
* P
* Q
* R
* S
* T
* U
* V
* W
* X
* Y
* Z
* †Utharocrinus
** †Utharocrinus pentanodus

## V

* A
* B
* C
* D
* E
* F
* G
* H
* I
* J
* K
* L
* M
* N
* O
* P
* Q
* R
* S
* T
* U
* V
* W
* X
* Y
* Z
* †Valhallites
** †Valhallites ornatus – type locality for species
** †Valhallites tuberculatus – type locality for species
** †Valhallites westforkensis – type locality for species
* †Verneuilites
** †Verneuilites pygmaeus
* †Virgaspongia – type locality for genus
** †Virgaspongia ichnata – type locality for species
* †Virginiata
** †Virginiata arkansana
* †Voiseyella
* †Vorticina
** †Vorticina venata

## W

* A
* B
* C
* D
* E
* F
* G
* H
* I
* J
* K
* L
* M
* N
* O
* P
* Q
* R
* S
* T
* U
* V
* W
* X
* Y
* Z
* †Wichitoceras
** †Wichitoceras compressum
* †Wiedeyoceras
** †Wiedeyoceras williamsi – type locality for species
* †Wilkingia
** †Wilkingia inflata – or unidentified comparable form
* †Winslowoceras
** †Winslowoceras henbesti – type locality for species

## X

* A
* B
* C
* D
* E
* F
* G
* H
* I
* J
* K
* L
* M
* N
* O
* P
* Q
* R
* S
* T
* U
* V
* W
* X
* Y
* Z
* †Xenocheilos
** †Xenocheilos minutum

## Y

* A
* B
* C
* D
* E
* F
* G
* H
* I
* J
* K
* L
* M
* N
* O
* P
* Q
* R
* S
* T
* U
* V
* W
* X
* Y
* Z
* †Yochelsonospira
** †Yochelsonospira tenuilineata

## Z

* A
* B
* C
* D
* E
* F
* G
* H
* I
* J
* K
* L
* M
* N
* O
* P
* Q
* R
* S
* T
* U
* V
* W
* X
* Y
* Z
* †Zaphrentites
** †Zaphrentites arkansanus
* †Zia
* †Zygopleura – report made of unidentified related form or using admittedly obsolete nomenclature