# List of the Paleozoic life of Maryland

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

## A

* 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
* †Acanthopecten – tentative report
** †Acanthopecten armigerus
** †Acanthopecten carboniferus
* †Acanthotriletes
** †Acanthotriletes pullus
* †Acoblatta – type locality for genus
** †Acoblatta argillacea – type locality for species
* †Actinopteria
** †Actinopteria boydi
** †Actinopteria boydii
** †Actinopteria decussata
* †Aglaoglypta
** †Aglaoglypta maera
* †Ambloblatta – type locality for genus
** †Ambloblatta bassleri – type locality for species
* †Ambocoelia
** †Ambocoelia umbonata
* †Ambonychia
* †Amphiscapha
** †Amphiscapha catilloides
* Fossils of the Ordovician-Permian bryozoan Amplexopora †Amplexopora
* †Anapiculatisporites
** †Anapiculatisporites crassisetus – type locality for species
* †Anazyga
** †Anazyga recurvirostra – tentative report
* †Ancyrospora
** †Ancyrospora ancyrea
* †Aneurospora
** †Aneurospora semizonalis
* †Anoplotheca
* †Anthraconeilo
** †Anthraconeilo taffiana
* †Aparchites
** †Aparchites punctillosa
* †Archaeoscyphia
* †Archaeotriletes
** †Archaeotriletes aduncus
* †Archaeozonotriletes
** †Archaeozonotriletes notatus
* †Archimylacris
** †Archimylacris delicata – type locality for species
* †Arthroacantha
** †Arthroacantha punctobrachiata – or unidentified comparable form
* †Astartella
** †Astartella concentrica
** †Astartella vera
* †Atlanticocoelia
* †Atrypa
** Fossilized shell of the Silurian-Late Devonian brachiopod Atrypa reticularis †Atrypa reticularis – report made of unidentified related form or using admittedly obsolete nomenclature
* †Aviculopecten

## B

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* I
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* M
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* †Bactrites
* Bairdia
* †Bassipterus
** †Bassipterus virginicus
* †Batostomella
* †Bellefontia
** †Bellefontia collieana – tentative report
* Fossilized shell of the Silurian-Early Triassic mollusc Bellerophon †Bellerophon
** †Bellerophon clarki
* †Beyrichia
** †Beyrichia moodeyi
** †Beyrichia veronica
* †Biharisporites
** †Biharisporites maguashensis
* †Bolbiprimitia
* †Bollia
** †Bollia immersa
** †Bollia nitida
** †Bollia pulchella
* †Bonnemaia
** †Bonnemaia celsa
** †Bonnemaia perlonga
* †Brachymylacris
** †Brachymylacris martini – type locality for species
* †Brochotriletes
* †Bucania – tentative report
* †Buthotrephis
** †Buthotrephis gracilis
* †Buthrotrephis
* †Byssonychia
** †Byssonychia radiata
* Bythocypris
** †Bythocypris obesa
** †Bythocypris pergracilis

## C

* A
* B
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* D
* E
* F
* G
* H
* I
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* L
* M
* N
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* P
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* Y
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* †Calamospora
** †Calamospora atava
** †Calamospora nigrata
* †Calymene
** †Calymene camerata
** †Calymene cresapensis
** Fossils in enrolled posture of the Silurian trilobite Calymene niagarensis †Calymene niagarensis – or unidentified comparable form
** †Calymene niagraensis
* †Camarotoechia
** †Camarotoechia andrewsi
** †Camarotoechia litchfieldensis
** †Camarotoechia tonolowayensis
* †Cariniferella
** †Cariniferella carinata
* †Cavellina
* †Ceratopea
* †Cheliphlebia – tentative report
** †Cheliphlebia argillacea – type locality for species
* †Chonetes
** †Chonetes novascoticus
* †Chonetina
** †Chonetina verneuilianus
* †Chonostrophia
* Assemblage of fossilized shells of the Ordovician brachiopod Cincinnetina †Cincinnetina
** †Cincinnetina multisecta
* †Clidophorus
** †Clidophorus nitidus
* †Clitendoceras
* †Coelospira
** †Coelospira nitens
** †Coelospira sulcata
* †Composita
** †Composita ovata – tentative report
* †Conularia
** †Conularia niagarensis
* †Convolutispora
** †Convolutispora subtilis
* †Coreanoceras
* Fossil of the Middle Ordovician-Carboniferous horn coral Cornulites †Cornulites
** †Cornulites concavus
** †Cornulites rosehillensis
* †Corvellites
* †Crurithyris
** †Crurithyris planoconvexa
* †Cryptolithus
* †Ctenodonta
** †Ctenodonta subreniformis
* †Culunana
** †Culunana attenuata
* †Cupularostrum
** †Cupularostrum contracta
* †Cyathophyllum
* †Cymatospira
** †Cymatospira montfortianus
* †Cyphomylacris – type locality for genus
** †Cyphomylacris atrata – type locality for species
* †Cyphotrypa
* †Cypricardella
** †Cypricardella crassa
** †Cypricardella cumberlandiae
** †Cypricardella gregaria
** †Cypricardella nitidula
** †Cypricardella tenuistriata
* †Cypricardinia
** †Cypricardinia elegans
* †Cyrtina
* †Cyrtodontula
** †Cyrtodontula subtruncata

## D

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* †Dakeoceras
* Fossil of the Late Ordovician-Middle Devonian trilobite Dalmanites †Dalmanites
** †Dalmanites limulurus
* †Dekayia
* †Delthyris
** †Delthyris vanuxemi
* †Derbyia
** †Derbyia crassa
* †Diaphanospora
** †Diaphanospora reticulatus
* †Diaphelasma
* †Dibolbina
** †Dibolbina cristata
* †Dictyotriletes
* †Dinoblatta – type locality for genus
** †Dinoblatta cubitalis – type locality for species
** †Dinoblatta fortis – type locality for species
* †Diparelasma
* †Dizygopleura
** †Dizygopleura acuminata
** †Dizygopleura carinata
** †Dizygopleura conjugata
** †Dizygopleura costata
** †Dizygopleura gibba
** †Dizygopleura halli
** †Dizygopleura intermedia
** †Dizygopleura micula
** †Dizygopleura perrugosa
** †Dizygopleura pricei
** †Dizygopleura proutyi
** †Dizygopleura simulans
** †Dizygopleura subdivisa
** †Dizygopleura subovalis
** †Dizygopleura swartzi
** †Dizygopleura symmetrica
* Life restoration of the Silurian eurypterid ("sea scorpion") Dolichopterus †Dolichopterus
* †Doloresella
* †Donaldina
** †Donaldina stevensana
* †Drepanellina
** †Drepanellina clarki
** †Drepanellina ventralis
* †Dunbarella
** †Dunbarella striata – type locality for species

## E

* A
* B
* C
* D
* E
* F
* G
* H
* I
* J
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* L
* M
* N
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* P
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* W
* X
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* †Ecculiomphalus
* †Edmondia
** †Edmondia aspenwallensis
** †Edmondia pseudoreflexa – type locality for species
* †Eldredgeops
** †Eldredgeops rana
* †Elita
* †Ellesmeroceras
* †Emphanisporites
** †Emphanisporites annulatus
** †Emphanisporites rotatus
* †Encrinurus
** †Encrinurus ornatus
* †Endocycloceras
** †Endocycloceras legorense
* †Eospirifer
** †Eospirifer crispus
* Life restoration of the Silurian-Early Devonian eurypterid ("sea scorpion") Erettopterus †Erettopterus – tentative report
* †Escharendoceras
* †Euchondria
** †Euchondria levicula – tentative report
* †Eukloedenella
** †Eukloedenella elongata
** †Eukloedenella punctillosa
** †Eukloedenella sinuata
** †Eukloedenella sulcifrons
** †Eukloedenella umbilicata
* †Euomphalus
* †Euphemites
** †Euphemites vittatus
* Life restoration of Silurian eurypterid ("sea scorpion") Eurypterus †Eurypterus
** †Eurypterus remipes
* †Euthydesma

## F

* A
* B
* C
* D
* E
* F
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* H
* I
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* M
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* Fossil of the Late Ordovician-Permian tabulate coral Favosites †Favosites
** †Favosites niagarensis – or unidentified comparable form
* †Finkelnburgia
** †Finkelnburgia virginica – tentative report
* †Fistulipora
* †Flexicalymene
* †Floweria
** †Floweria chemungensis
* †Foveosporites
** †Foveosporites insculptus

## G

* A
* B
* C
* D
* E
* F
* G
* H
* I
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* M
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* †Gasconadia
** †Gasconadia putilla
* †Geminospora
** †Geminospora svalbardiae
** †Geminospora tuberculata
* †Girtyspira
** †Girtyspira minuta
* †Glabrocingulum
** †Glabrocingulum grayvillense
** †Glabrocingulum ornatum
* †Glyptoglossella
** †Glyptoglossella cavellosa
* †Glyptorthis
** †Glyptorthis equiconvexa – type locality for species
* Fossilized shell of the Late Devonian-Late Triassic ammonoid cephalopod Goniatites †Goniatites
* †Grammysia
* †Gyrodoma
** †Gyrodoma marylandica

## H

* A
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* †Halliella
** †Halliella fissurella
** †Halliella subequata
* Fossil of the Ordovician bryozoan ("moss animal") Hallopora †Hallopora
* †Healdia
* †Hebertella
** †Hebertella sinuata
* †Hemimylacris – type locality for genus
** †Hemimylacris bassleri – type locality for species
* †Heterotrypa
* †Hindella
** †Hindella congregata
* †Hippocardia
** †Hippocardia cumberlandiae – type locality for species
* Fossilized shells of the Ordovician-Carboniferous sea snail Holopea †Holopea
* †Homeospira
** †Homeospira evax
* †Hormotoma
** †Hormotoma hopkinsi
** †Hormotoma rowei
* †Hyolithes
* †Hystricosporites
** †Hystricosporites porcatus
* †Hystriculina – tentative report
** †Hystriculina wabashensis
* †Hystricurus

## I

* A
* B
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* F
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* H
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* †Inaperaturate
* †Ischyrodonta – tentative report
** †Ischyrodonta truncata
* Fossil of the Middle-Late Ordovician giant trilobite Isotelus. †Isotelus

## J

* A
* B
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* F
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* †Juresania
** †Juresania symmetrica – tentative report

## K

* A
* B
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* F
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* H
* I
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* L
* M
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* P
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* †Kitikamispira
** †Kitikamispira concinna
** †Kitikamispira multistriata
* †Kloedenella
** †Kloedenella cornuta
** †Kloedenella immersa
** †Kloedenella intermedia
** †Kloedenella nitida
* †Kloedenia
** †Kloedenia normalis
* †Kyammodes
** †Kyammodes swartzi

## L

* A
* B
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* D
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* F
* G
* H
* I
* J
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* M
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* P
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* W
* X
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* Z
* †Lasiocrinus
** †Lasiocrinus scoparius – or unidentified comparable form
* †Lecanospira
** †Lecanospira compacta – tentative report
* †Leiorhynchus
* †Leperditia
** †Leperditia alta
** †Leperditia elongata
* †Leptaena
** †Leptaena rhomboidalis – report made of unidentified related form or using admittedly obsolete nomenclature
* †Lepterditia
* †Leptodesma
** †Leptodesma marylandica
** †Leptodesma naviforme
** †Leptodesma nitida
** †Leptodesma spinerigum
** †Leptodesma subplana – or unidentified comparable form
* †Leptostrophia
** †Leptostrophia proutyi
* †Lesueurilla
* †Levenea
* †Lichenaria
* Shell of the Cambrian-modern brachiopod Lingula †Lingula
** †Lingula carbonaria
** †Lingula gracilis
* †Linoproductus
** †Linoproductus prattenianus
* †Liocalymene
** †Liocalymene clintoni
* †Lobosiphon
* †Longispina
* †Lophotriletes
** †Lophotriletes atratus
* †Loxonema
* †Lyrodesma
** †Lyrodesma poststriatum
* Life restoration of the Permian snake-like amphibian Lysorophus showing speculative egg-coiling behavior †Lysorophus
* †Lytospira

## M

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* †Macluritella
** †Macluritella marylandica – type locality for species
* †Mastigobolbina
** †Mastigobolbina arguta
** †Mastigobolbina lata
** †Mastigobolbina typus
* †Mcqueenoceras
* †Meekospira
** †Meekospira percuta – or unidentified related form
* †Megamolgophis
** †Megamolgophis agostini
* †Melanoblattula – type locality for genus
** †Melanoblattula nigrescens – type locality for species
* †Meristina
* Fossilized shell of the Carboniferous-Permian nautiloid cephalopod Metacoceras †Metacoceras
** †Metacoceras marylandica – type locality for species
* †Modiolopsis
** †Modiolopsis gregarius
** †Modiolopsis leightoni
** †Modiolopsis modiolaris
* †Modiomorpha
* †Monticulipora
* †Mylacris
** †Mylacris lapsa – type locality for species
* †Mysticoceras

## N

* A
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* †Narkema
** †Narkema alternatum – type locality for species
* Fossilized shell of the Early Devonian – Triassic sea snail Naticopsis †Naticopsis
* †Neochonetes
** †Neochonetes granulifer
* †Neospirifer
** †Neospirifer dunbari – tentative report
* †Nucleospira
* †Nucularca
** †Nucularca pectunculoides
* †Nuculites
* †Nuculopsis
** †Nuculopsis anadontoides
** †Nuculopsis girtyi

## O

* A
* B
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* D
* E
* F
* G
* H
* I
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* M
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* †Obolella
* †Obolus – tentative report
* †Ochetopteron – type locality for genus
** †Ochetopteron canaliculatum – type locality for species
* †Octonaria
** †Octonaria muricata
* Restoration of the Cambrian trilobite Olenellus †Olenellus
* †Olethroblatta
** †Olethroblatta lineolata – type locality for species
* †Ophileta
* †Orbiculoidea
** †Orbiculoidea missouriensis – tentative report
* †Ormoceras
** †Ormoceras neumani
* †Orospira
* †Orthoceras
** †Orthoceras mackenzicum
* †Orthomylacris
** †Orthomylacris berryi – type locality for species
** †Orthomylacris recta – type locality for species
* †Orthonychia
** †Orthonychia prosseri
** †Orthonychia unguiculata
* †Orthopora
* †Orthorhynchula
** †Orthorhynchula linneyi

## P

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* †Pachyblatta – type locality for genus
** †Pachyblatta convexa – type locality for species
** †Pachyblatta radiata – type locality for species
* †Palaeoneilo
** †Palaeoneilo angusta
** †Palaeoneilo brevis
** †Palaeoneilo clarkei
** †Palaeoneilo constricta
** †Palaeoneilo crassa
** †Palaeoneilo petila
** †Palaeoneilo plana
* †Palaeozygopleura
** †Palaeozygopleura glabra – tentative report
** †Palaeozygopleura hamiltoniae
** †Palaeozygopleura styliola
** †Palaeozygopleura terebra
* †Paleonucula
** †Paleonucula croneisi
* †Paleyoldia – type locality for genus
** †Paleyoldia glabra
* †Paracyclas
** †Paracyclas lirata
* †Paraechmina
** †Paraechmina abnormis
** †Paraechmina crassa
** †Paraechmina depressa
** †Paraechmina postica
** †Paraechmina spinosa
* †Parajuresania
** †Parajuresania nebrascensis – tentative report
* †Parallelodon
** †Parallelodon tenuistriata
* †Patellilabia
** †Patellilabia tentoriolum – tentative report
* †Permophorus
** †Permophorus oblongus
* †Peronopora – tentative report
* †Pharkidonotus
** †Pharkidonotus percarinatus
* †Pholidops
** †Pholidops squamiformis
* †Pholidostrophia
* †Phragmosiphon
* †Phymatopleura
** †Phymatopleura brazonensis
* †Pintopsis
* †Plagioglypta
** †Plagioglypta annulostriata
* Fossilized shell of the Silurian-Early Triassic sea snail Platyceras †Platyceras
** †Platyceras marylandicum
** †Platyceras niagarense
* †Platysiphon
* †Plectonotus
** †Plectonotus boucoti
* †Plethobolbina
** †Plethobolbina cornigera
** †Plethobolbina typicalis
* †Pleurophorus
** †Pleurophorus occidentalis
* †Pliendoceras
* †Polidevcia – type locality for genus
** †Polidevcia bellistriata
* †Polytoechia – tentative report
* †Praenucula
** †Praenucula lavata
* †Proterocameroceras
* †Prothyris
** †Prothyris singewaldi – type locality for species
* †Protodouvillina
* †Psalikilus
* †Pseudoatrypa
* †Pseudorthoceras
** †Pseudorthoceras knoxense
* †Pseudozygopleura
** †Pseudozygopleura girtyi – or unidentified comparable form
* †Pterinea
** †Pterinea demissa
** †Pterinea flintstonensis
* Restoration of the Silurian-Middle Devonian eurypterid ("sea scorpion") Pterygotus †Pterygotus
** †Pterygotus marylandicus
* †Punctatisporites
** †Punctatisporites calamites
** †Punctatisporites glaber
** †Punctatisporites laevigatus
** †Punctatisporites solidus

## R

* A
* B
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* D
* E
* F
* G
* H
* I
* J
* K
* L
* M
* N
* O
* P
* Q
* R
* S
* T
* U
* V
* W
* X
* Y
* Z
* †Rafinesquina
** †Rafinesquina alternata
** †Rafinesquina corrugata
* †Resserella
** †Resserella elegantula
* †Reticularia
** †Reticularia bicostata
* †Retroclitendoceras
* †Retusotriletes
** †Retusotriletes goensis
** †Retusotriletes planus
** †Retusotriletes punctatus
* †Rhabdosporites
** †Rhabdosporites parvulus
* †Rhipidomella
* †Rhombopora – tentative report
** †Rhombopora lepidendroides – or unidentified comparable form
* †Rhynchospirina
** †Rhynchospirina globosa
* †Ribeiria
* †Rioceras
* †Ruedemannia – tentative report
** †Ruedemannia lirata

## S

* A
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* F
* G
* H
* I
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* M
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* P
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* U
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* X
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* †Samarisporites
** †Samarisporites grossicorrugatus – type locality for species
** †Samarisporites grossicorugatus
* †Sansabella
* †Schellwienella
** †Schellwienella elegans
** †Schellwienella rugosa
** †Schellwienella tenuis
* †Schizodus
** †Schizodus curtus
** †Schizodus oherni
** †Schizodus wheeleri
* †Schuchertella
* †Serpulopsis
** †Serpulopsis insita
* †Shansiella
** †Shansiella carbonaria – tentative report
* †Shellwienella
** †Shellwienella elegans
* Modern specimen of the marine bivalve Solemya Solemya
** †Solemya radiata
** †Solemya trapezoides
* †Soleniscus
** †Soleniscus primigenius
* † Solenopsis
** †Solenopsis solenoides
* †Sowerbyella
** †Sowerbyella serica
** †Sowerbyella sericea
* †Spaniodera – tentative report
** †Spaniodera simplex – type locality for species
* †Spelaeotriletes
* †Spinozonotriletes
* Fossilized shell of the Late Ordovician-Late Triassic brachiopod Spirifer †Spirifer
** †Spirifer disjunctus
** †Spirifer vanuxemi
* †Stegerhynchus
** †Stegerhynchus neglectum
* †Stenosiphon
* †Stereostylus
** †Stereostylus profundus
* †Stichotrophia
* †Straparollus
** †Straparollus marylandicus
* †Strobeus
** †Strobeus paludinaeformis
* Fossilized shell of the Ordovician-Silurian brachiopod Strophomena †Strophomena
* †Syntrophinella

## 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
* †Tainoceras
** †Tainoceras monolifer
* †Tancrediopsis
** †Tancrediopsis cuneata
* Fossilized shell of the Early Ordovician-Late Devonian probable mollusc Tentaculites †Tentaculites
** †Tentaculites gyracanthus
** †Tentaculites minutus
** †Tentaculites niagarense
** †Tentaculites niagarensis
* †Tetralobula
* †Trigonocera
* †Trimerus
** †Trimerus delphinocephalus
* †Tritoechia
* †Truncalosia
* †Turbonopsis
** †Turbonopsis coronola – type locality for species

## 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
* †Uncinulus
** †Uncinulus marylandicus
** †Uncinulus obtusiplicatus
** †Uncinulus stricklandi

## 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
* †Verrucosisporites
** †Verrucosisporites rarituberculatus

## 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
* †Waagenella
** †Waagenella crassus
* Fossilized head of the Silurian eurypterid ("sea scorpion") Waeringopterus †Waeringopterus
** †Waeringopterus cumberlandicus
* †Welleria
** †Welleria obliqua
* †Whitfieldella
** †Whitfieldella marylandica
* †Worthenia
** †Worthenia castlemanensis – 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
* †Xenelasma

## 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
* †Zygobeyrichia
** †Zygobeyrichia incipiens
** †Zygobeyrichia tonolowayensis
** †Zygobeyrichia ventricornis
** †Zygobeyrichia ventripunctata
* †Zygosella
** †Zygosella postica
* †Zygospira
** †Zygospira modesta