# List of the Paleozoic life of Minnesota

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

## A

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* G
* H
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* †Abludoglyptocrinus –
** †Abludoglyptocrinus charltoni
* †Acanthocrania
** †Acanthocrania granulosa
** †Acanthocrania setigeria
* †Acanthoparypha
** †Acanthoparypha evetti
* †Actinoceras
** †Actinoceras beloitense
** †Actinoceras bigsbyi
** †Actinoceras gravicentrum
** †Actinoceras janesvillensis
* †Actinodiscus
* †Aechmina
** †Aechmina cuspidata
** †Aechmina ionensis
* †Agelacrinites
* †Alaskadiscus
** †Alaskadiscus subacutus
* †Allodesma – type locality for genus
** †Allodesma subellipticum – type locality for species
* †Allumettoceras
** †Allumettoceras carletonense – or unidentified comparable form
** †Allumettoceras planodorsatum
* †Ambonychia
** †Ambonychia tenuis
* †Ambonychiopsis
* †Amecystis
** †Amecystis woodi
* †Americoncha
** †Americoncha marginata
* †Amorphognathus
** †Amorphognathus superbus
* †Amphilichas
** †Amphilichas cucullus – or unidentified comparable form
* †Amygdalocystites
* †Anaspyroceras
** †Anaspyroceras anellus
** †Anaspyroceras calvini
** †Anaspyroceras clermontense
** †Anaspyroceras perroti
* †Anazyga
** †Anazyga recurvirostra
* †Anolotichia
** †Anolotichia impolita
* †Antiplectoceras – tentative report
* †Anulocrinus
** †Anulocrinus forrestonensis
* †Aparchites
** †Aparchites barbatus
** †Aparchites carinatus
** †Aparchites chatfieldensis
** †Aparchites ellipticus
** †Aparchites fimbriatus
** †Aparchites macrus
** †Aparchites paratumida
* †Apycnodiscus
* †Archaeocrinus
** †Archaeocrinus obconicus
* †Archinacella
** †Archinacella cingulata
** †Archinacella deleta
** †Archinacella simplex
** †Archinacella simulatrix
** †Archinacella valida
* †Aristerella
* †Armenoceras
** †Armenoceras clermontense
** †Armenoceras iowense
* †Arthroclema
** †Arthroclema armatum
* †Arthropora
** †Arthropora simplex
* †Arthrostylus
** †Arthrostylus conjunctus
** †Arthrostylus obliquus
* †Aspidopora
* †Astreptodictya
** †Astreptodictya acuta
** †Astreptodictya elegans
** †Astreptodictya fimbriata
** †Astreptodictya pumila
* †Astrocystites
* †Ateleocystites
** †Ateleocystites guttenbergensis
* †Athrophragma
** †Athrophragma foliata
* †Austinella
** †Austinella kankakensis –

## B

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* †Bairdiocypris –
** †Bairdiocypris granti
* †Basilicus
** †Basilicus barrandi
* †Bassleratia
** †Bassleratia typa
* †Bathyurus
** †Bathyurus longispinus
* †Batostoma
** †Batostoma fertile
** †Batostoma magnopora
** †Batostoma winchelli
* †Bellimurina
** †Bellimurina charlottae
* †Bellornatia
** †Bellornatia tricollis
* †Belodina
** †Belodina compressa
** †Belodina confluens
* †Beloitoceras
** †Beloitoceras carveri
** †Beloitoceras grafense
** †Beloitoceras houghtoni
** †Beloitoceras huronense – or unidentified comparable form
** †Beloitoceras janesvillense
** †Beloitoceras lycum
** †Beloitoceras norwoodi
** †Beloitoceras pandion
** †Beloitoceras plebeium
** †Beloitoceras whitneyi
* †Berkeia – type locality for genus
** †Berkeia typica – type locality for species
* †Beyrichia
** †Beyrichia irregularis
* †Bodeiceras
** †Bodeiceras oxygonium
* †Bollia
** †Bollia regularis
** †Bollia ruthae
** †Bollia subaequata
** †Bollia subaequeata
* Reconstructive diagram (left) of a fossil (right) of the Ordovician sea urchin Bothriocidaris. The short spines which were attached to the tubercles are not drawn. †Bothriocidaris
** †Bothriocidaris solemi
* †Brachytomaria
** †Brachytomaria semele
* †Bromidella
** †Bromidella depressa
** †Bromidella rhomboides
* †Bryantodina
** †Bryantodina abrupta
** †Bryantodina typicalis
* †Bucania
** †Bucania elliptica
** †Bucania halli
** †Bucania minnesotensis
** †Bucania sublata
* †Bullatella
** †Bullatella granilabiatus
** †Bullatella granlabiatus
* †Bumastoides
** †Bumastoides milleri
** †Bumastoides porrectus
* Life restoration of the Early Ordovician-Silurian trilobite Bumastus †Bumastus
** †Bumastus orbicaudatus
* †Byrsolopsina
** †Byrsolopsina centipunctata
** †Byrsolopsina normella
** †Byrsolopsina ovata
** †Byrsolopsina planilateralis
* Bythocypris
** †Bythocypris curta
** †Bythocypris furnishi
* †Bythopora
** †Bythopora subgracilis –

## C

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* †Calceocrinus
** †Calceocrinus gossmani
** †Calceocrinus levorsoni
* Fossil of the Early Ordovician-Early Devonian trilobite Calymene †Calymene
** †Calymene mamillate
** †Calymene winchelli
* †Camaraspis
** †Camaraspis convexus
* †Camaraspoides
** †Camaraspoides berkeyi
* †Camellaspongia – type locality for genus
** †Camellaspongia tumula – type locality for species
* Restoration of the Middle Ordovician-Silurian nautiloid cephalopod Cameroceras feeding on an Aphetoceras, while a quartet of Cyclostomiceras swim by †Cameroceras
** †Cameroceras alternatum – or unidentified comparable form
** †Cameroceras hennepini
** †Cameroceras inopinatum – type locality for species
** †Cameroceras stillwaterense – type locality for species
* †Campylorthis
** †Campylorthis deflecta
* †Carabocrinus
** †Carabocrinus dicyclicus
** †Carabocrinus magnificus
** †Carabocrinus oogyi
** †Carabocrinus radiatus
** †Carabocrinus slocomi
* †Carinaropsis
** †Carinaropsis cymbula
** †Carinaropsis minima
* †Cataschisma
** †Cataschisma convexum
* †Centrocyrtoceras
** †Centrocyrtoceras annulatum
** †Centrocyrtoceras duplicostatum
** †Centrocyrtoceras rotundum
* †Ceratopea
** †Ceratopea canadensis
** †Ceratopea parvum – type locality for species
** †Ceratopea pygmaea – type locality for species
* †Ceratopsis
** †Ceratopsis chambersi
** †Ceratopsis humilinoda
** †Ceratopsis quadrifida
* †Ceraurinella
** †Ceraurinella scofieldi
** †Ceraurinella templetoni
* †Ceraurinus
** †Ceraurinus icarus
* Fossil of the Middle-Late Ordovician trilobite Ceraurus †Ceraurus
** †Ceraurus pleurexanthemus
** †Ceraurus pleurexanthomus
* †Charactoceras
** †Charactoceras laddi
* †Chariocephalus
** †Chariocephalus whitfieldi
* †Chasmatopora
** †Chasmatopora reticulata
* †Cheilocephalus
** †Cheilocephalus stcroixensis
* †Cheirocrinus
* †Chidleyenoceras
* †Chirognathus
** †Chirognathus duodactylus
* †Cincinnaticrinus
** †Cincinnaticrinus varibrachialus
* Assemblage of fossilized shells of the Ordovician brachiopod Cincinnetina †Cincinnetina
** †Cincinnetina minnesotensis – type locality for species
* †Clathrospira
** †Clathrospira conica
** †Clathrospira subconica
* †Cleiocrinus
* †Cleionychia
* †Coelocerodontus
** †Coelocerodontus trigonius
* †Colpodon
* †Colpomya
* Fossil of the Ordovician bryozoan Constellaria †Constellaria
** †Constellaria varia
* †Conularia
* †Cordylodus
** †Cordylodus delicatus
* †Cornites
* †Coronocystis
** †Coronocystis durandensis
* †Cotteroceras
** †Cotteroceras compressum
* †Cotylahindia – type locality for genus
** †Cotylahindia panaca – type locality for species
* †Crania
** †Crania reversa
* †Craniops
** †Craniops minor
* †Cremacrinus
** †Cremacrinus arctus
** †Cremacrinus crossmani
** †Cremacrinus gerki
** †Cremacrinus guttenbergensis
** †Cremacrinus punctatus
* †Cryptophyllus
** †Cryptophyllus obloides
** †Cryptophyllus oboloides
** †Cryptophyllus sulcatus
* †Crytoniodus
** †Crytoniodus complicatus
* †Ctenobolbina
** †Ctenobolbina emaciata
** †Ctenobolbina maquoketensis
* †Ctenodonta
** †Ctenodonta novicea
** †Ctenodonta oviformis – type locality for species
** †Ctenodonta similis
** †Ctenodonta subnasuta – type locality for species
* †Culumbodina
** †Culumbodina penna
* †Cuneamya
* †Cupulocrinus
** †Cupulocrinus canaliculatus
** †Cupulocrinus conjugans
** †Cupulocrinus graciis – or unidentified related form
** †Cupulocrinus gracilis
** †Cupulocrinus humilis
** †Cupulocrinus jewetti
** †Cupulocrinus latibrachiatus – or unidentified related form
** †Cupulocrinus levorsoni
** †Cupulocrinus molanderi
** †Cupulocrinus plattevillensis
* †Curtognathus
* †Cyclocystoides
** †Cyclocystoides halli
* †Cyclonema
** †Cyclonema aiens
** †Cyclonema percarinata
** †Cyclonema textilis
** †Cyclonema varicosum
* †Cyclospira
** †Cyclospira bisulcata
* †Cymatonota
* †Cyptendoceras
** †Cyptendoceras ruedemanni
* †Cyrtocerina
** †Cyrtocerina crenulata
** †Cyrtocerina schoolcrafti
* †Cyrtodonta
** †Cyrtodonta descriptus
** †Cyrtodonta dignus
** †Cyrtodonta grandis
* †Cyrtodontula
** †Cyrtodontula praecipita – type locality for species
* †Cyrtoizoceras
** †Cyrtoizoceras minneapolis
* †Cyrtolites
** †Cyrtolites dilatus
** †Cyrtolites disjunctus
** †Cyrtolites minor
** †Cyrtolites ornatus
** †Cyrtolites retrorsus
* †Cyrtonellopsis
** †Cyrtonellopsis vetulum
* †Cyrtospira
** †Cyrtospira wykoffensis
* †Cyrtostropha
** †Cyrtostropha salteri –

## D

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* †Daidia
** †Daidia subconica – type locality for species
* †Dalmanella
** †Dalmanella rara – or unidentified comparable form
** †Dalmanella sculpta – tentative report
* †Dapsilodus
** †Dapsilodus mutatus
* †Deceptrix
* †Deckeroceras
** †Deckeroceras clermontense
* †Deiroceras
** †Deiroceras scofieldi
* †Dekayella
** †Dekayella praenuntia
* †Delotaxis
* †Dendrocrinus
** †Dendrocrinus acutidactylus – or unidentified related form
** †Dendrocrinus casei
* †Desmograptus
** †Desmograptus cancellatus
* †Diceromyonia
** †Diceromyonia ignota
* †Dicranella
** †Dicranella bicornis
** †Dicranella marginata
** †Dicranella marinata
** †Dicranella simplex
** †Dicranella spinosa
** †Dicranella typa
* †Diestoceras
** †Diestoceras alceum
** †Diestoceras clarkei
* †Dilobella
** †Dilobella simplex
** †Dilobella typa
* †Dinorthis
** †Dinorthis pectinella
* †Diorthelasma
** †Diorthelasma weissi – type locality for species
* Cambrian graptolite Diplograptus †Diplograptus
** †Diplograptus peosta
* †Doleroides
** †Doleroides pervetus
* †Dolichoharpes
** †Dolichoharpes ottawaensis
* †Drepanoistodus
** †Drepanoistodus suberectus
* †Drumaspis
** †Drumaspis sabulosa
** †Drumaspis tanycodia
* †Dvorakia
** †Dvorakia chattertoni – type locality for species
** †Dvorakia klapperi –

## E

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* †Eccyliopterus
** †Eccyliopterus owenanus
* †Ectenaspis
** †Ectenaspis beckeri – type locality for species
* †Ectenocrinus
** †Ectenocrinus raymondi
** †Ectenocrinus simplex
* †Ectomaria
** †Ectomaria pagoda
** †Ectomaria prisca
* †Edrioaster
** †Edrioaster bigsbyi
* †Ellesmeria
** †Ellesmeria scobeyi
* †Ellesmeroceras
** †Ellesmeroceras winonicum
* †Ellipsocephaloides
** †Ellipsocephaloides curtus
** †Ellipsocephaloides gracilis
* †Elliptocryprites
** †Elliptocryprites paracylindrica – type locality for species
* †Elliptocyprites
** †Elliptocyprites paracylindrica – type locality for species
* Fossilized shells and restored appearances of the Middle-Late Ordovician nautiloid cephalopod Endoceras †Endoceras
** †Endoceras atkinsonense
** †Endoceras clarkei
** †Endoceras clermontense
** †Endoceras decorahense
** †Endoceras eburneolum – type locality for species
** †Endoceras fulgar
** †Endoceras gracillimum
** †Endoceras kayi
** †Endoceras proteiforme
** †Endoceras thomasi
* †Eobelodina
** †Eobelodina hormacola
* †Eochonetes
** †Eochonetes recedens
* †Eomonorachus
** †Eomonorachus intermedius
* †Eoplectodonta
** †Eoplectodonta recedens
** †Eoplectodonta saxea
* †Eoschmidtella
** †Eoschmidtella umbonata
* †Eotomaria
** †Eotomaria dryope
** †Eotomaria vicina
* †Ephippiorthoceras
** †Ephippiorthoceras laddi
** †Ephippiorthoceras tenuistriatum
* †Eremotrema – tentative report
** †Eremotrema emacerata
* †Eridotrypa
** †Eridotrypa aedilis
** †Eridotrypa exigua
* †Erismodus
** †Erismodus quadridactylus
* †Eroicaspira
** †Eroicaspira bellicincta
* †Erratencrinurus
** †Erratencrinurus vigilans
* †Escharopora
** †Escharopora subrecta
* †Eukloedenella
** †Eukloedenella richmondensis
* †Eumorphocystis
* †Eunema
** †Eunema centralis
** †Eunema concinnula
** †Eunema helicteres
** †Eunema quadrisulcata
** †Eunema simile
* †Euomphalopsis
** †Euomphalopsis depressa – type locality for species
* †Euprimitia
** †Euprimitia celata
** †Euprimitia labiosa
** †Euprimitia linepunctata
** †Euprimitia sanctipauli
* †Eurychilina
** †Eurychilina cannonfallsensis – type locality for species
** †Eurychilina depressa
** †Eurychilina incurva
** †Eurychilina kayi – type locality for species
** †Eurychilina micropunctata – type locality for species
** †Eurychilina minutifoveata
** †Eurychilina partifimbriata
** †Eurychilina reticulata
** †Eurychilina subradiata
** †Eurychilina sugarcreekensis – type locality for species
** †Eurychilina ventrosa
* †Eurycystites
** †Eurycystites granosus
* †Eurymya
** †Eurymya plana
* †Eurystomites
** †Eurystomites kelloggi –

## F

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* †Fayettoceras – tentative report
** †Fayettoceras beloitense
* †Fisherities
* Fossil of the Middle Ordovician-Silurian trilobite Flexicalymene †Flexicalymene
** †Flexicalymene senaria
* †Floripatella
** †Floripatella humilis
* †Furcitella
** †Furcitella scofieldi
* †Fusispira
** †Fusispira angusta
** †Fusispira convexa
** †Fusispira inflata
** †Fusispira intermedia
** †Fusispira nobilis
** †Fusispira planulata
** †Fusispira spicula
** †Fusispira subbrevis
** †Fusispira subfusiformis
** †Fusispira ventricosa
** †Fusispira vittata –

## G

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* Gabriceraurus dentatus †Gabriceraurus
** †Gabriceraurus mifflinensis
* †Geisonoceras
** †Geisonoceras clermontense
** †Geisonoceras scofieldi
* †Globonema
** †Globonema niota
* †Glyptocrinus
** †Glyptocrinus ornatus – or unidentified related form
** †Glyptocrinus pustulosis
** †Glyptocrinus tridactylus
* †Glyptocystites
* †Glyptocystitid – type locality for genus
* †Glyptorthis
** †Glyptorthis bellarugosa
** †Glyptorthis insculpta
* †Gonioceras
** †Gonioceras anceps
** †Gonioceras homerense
** †Gonioceras kayi
** †Gonioceras occidentale
* †Goniophora
** †Goniophora absimilis
* †Gorbyoceras
* †Graptodictya
** †Graptodictya proava
** †Graptodictya simplex
* †Grenprisa
** †Grenprisa billingsi
* Multiple views of a fossil of the Ordovician horn coral Grewingkia †Grewingkia
* †Gyronema
** †Gyronema pulchellum
** †Gyronema semicarinatum –

## H

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* †Hallatia
** †Hallatia convexa
** †Hallatia duplicata
** †Hallatia particylindrica
* †Halliella
** †Halliella magnipunctata
* Fossil of the Ordovician bryozoan ("moss animal") Hallopora †Hallopora
** †Hallopora dumalis
** †Hallopora goodhuensis
** †Hallopora multitabulata
** †Hallopora undulata
* †Hebertella
** †Hebertella occidentalis
* †Hebetoceras – tentative report
* †Helcionopsis
** †Helcionopsis depressum
** †Helcionopsis wisconsinensis
* †Helicotoma
** †Helicotoma planulata
* †Helopora
** †Helopora divaricata
* †Hemicystites
** †Hemicystites curtus
** †Hemicystites paulianus
* †Hemiphragma
** †Hemiphragma irrasum
** †Hemiphragma tenuimurale
* †Hesperidella
** †Hesperidella initialis
* †Hesperorthis
** †Hesperorthis tricenaria
* †Hindia
** †Hindia sphaeroidalis
* †Hiscobeccus
** †Hiscobeccus capax
* Fossilized shells of the Ordovician-Carboniferous sea snail Holopea †Holopea
** †Holopea ampla
** †Holopea appressa
** †Holopea concinnula
** †Holopea excelsa
** †Holopea insignis
** †Holopea obliqua
** †Holopea paludiniformis
** †Holopea pyrene
** †Holopea rotunda
** †Holopea similis
** †Holopea supraplana
* †Holtedahilina
** †Holtedahilina emaciata
* †Homotrypa
** †Homotrypa subramosa
* †Homotrypella
** †Homotrypella cribrosa
** †Homotrypella hospitalis
** †Homotrypella instabilis
* †Horiostomella
* †Hormotoma
** †Hormotoma artemesia
** †Hormotoma cassina
** †Hormotoma gracilis
** †Hormotoma minnesotensis
** †Hormotoma multivolvis
** †Hormotoma neglecta
** †Hormotoma oehlerti
** †Hormotoma subangulata
* †Hudsonaster
** †Hudsonaster narrawayi
** †Hudsonaster rugosus – or unidentified related form
* †Hybocrinus
** †Hybocrinus conicus
* †Hypseloconus – type locality for genus
** †Hypseloconus cornutiformis – type locality for species
** †Hypseloconus elongatus – type locality for species
* †Hypsiptycha
** †Hypsiptycha anticostiensis –

## I

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* †Icriodella
** †Icriodella superba
* †Icriodus
** †Icriodus calvini – type locality for species
** †Icriodus orri – type locality for species
* †Idahoia
** †Idahoia serapia
** †Idahoia serapio
** †Idahoia wisconsensis
* †Idiospira
** †Idiospira panderi
* †Illaenus
** †Illaenus americanus
* †Ischadites
** †Ischadites iowensis
* †Isorthoceras
** †Isorthoceras junceum
** †Isorthoceras sociale
* Fossil of the Middle-Late Ordovician giant trilobite Isotelus. †Isotelus
** †Isotelus gigas
** †Isotelus iowensis
** †Isotelus simplex
** †Isotelus susae
* †Isotomocrinus
** †Isotomocrinus minutus –

## K

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* †Kentlandoceras –
** †Kentlandoceras husseyi
** †Kentlandoceras schrocki – or unidentified comparable form
* †Kiesowia – tentative report
** †Kiesowia verrucosa
* Fossilized shells of the Middle Ordovician-Permian nautiloid cephalopod Kionoceras †Kionoceras
** †Kionoceras decorahense
** †Kionoceras postvillense
** †Kionoceras tenuitectum
** †Kionoceras thomasi
* †Kirengella
** †Kirengella rectilateralis – type locality for species
** †Kirengella stabilis – type locality for species
* †Kokenospira
** †Kokenospira costalis – type locality for species
* †Krausella
** †Krausella arcuata
** †Krausella curtispina
** †Krausella inaequalis
** †Krausella variata –

## L

* 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
* †Laccoprimitia
** †Laccoprimitia fillmorensis
* †Laddella
** †Laddella insueta
* †Lambeoceras
** †Lambeoceras confertum
** †Lambeoceras cultratum – or unidentified comparable form
* †Lecanospira
** †Lecanospira transversocordatus – type locality for species
* †Leperditella
** †Leperditella fryei
** †Leperditella macra
** †Leperditella millepunctata
** †Leperditella persimilis
* †Lepidocyclus
** †Lepidocyclus laddi
* †Lesueurilla
** †Lesueurilla beloitensis
* †Lichenaria
** †Lichenaria typa
* Shell of the Cambrian-modern brachiopod Lingula †Lingula
** †Lingula morsei
** †Lingula philomela
* †Lingulasma
** †Lingulasma galenensis
* †Lingulops
* †Liospira
** †Liospira americana
** †Liospira angustata
** †Liospira decipens
** †Liospira micula
** †Liospira modesta
** †Liospira obtusa
** †Liospira progne
** †Liospira vitruvia
* †Loganoceras
* †Lophospira
** †Lophospira decursa
** †Lophospira major
** †Lophospira milleri
** †Lophospira obliqua
** †Lophospira perangulata – type locality for species
** †Lophospira serrulata
** †Lophospira spironema
** †Lophospira ventricosa
* †Loxobucania
** †Loxobucania emmonsi
** †Loxobucania lindsleyi
* †Lyrodesma
** †Lyrodesma cannonense – type locality for species
* †Lytospira
** †Lytospira subrotunda
** †Lytospira undulatus –

## M

* 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
* †Maclurina
** †Maclurina bigsbyi
** †Maclurina manitobensis
* †Maclurites
** †Maclurites crassa
** †Maclurites cuneata
** †Maclurites depressus
** †Maclurites nitidus
** †Maclurites subrotunda
* Macrocypris
** †Macrocypris kayi
* †Macrocyproides
** †Macrocyproides clermontensis
* †Macrocyprus
** †Macrocyprus kayi
* †Macronotella
** †Macronotella arcta
** †Macronotella scofeldi
** †Macronotella scofieldi
* †Manespira
** †Manespira nicolleti
* †Manitoulinoceras
** †Manitoulinoceras neleum
** †Manitoulinoceras warsawense
** †Manitoulinoceras wykoffense
* †Maratia
** †Maratia mana
** †Maratia mara
** †Maratia micula
* †Matheria
* †Megamyonia
** †Megamyonia unicostata
* †Merocrinus
** †Merocrinus britonensis
* †Metaspyroceras
** †Metaspyroceras clarkei
** †Metaspyroceras minneapolis
** †Metaspyroceras nicolleti
** †Metaspyroceras perlineatum
** †Metaspyroceras wisconsinense
* †Michelinoceras
** †Michelinoceras beltrami
** †Michelinoceras multicameratum
* †Microcoelodus
* †Milleratia
** †Milleratia cincinnatiensis
* †Mitoclema
** †Mitoclema mundulum
* †Mixoconus
** †Mixoconus primus
* †Modiolodon
* †Modiolopsis
** †Modiolopsis fountainensis
** †Modiolopsis gregalis
** †Modiolopsis nana – type locality for species
* †Monocheilus
** †Monocheilus anatinum
** †Monocheilus micros
* †Monocyclic
** †Monocyclic inadunate
* †Monotrypa
* †Multioistodus
* †Myeinocystites
** †Myeinocystites crossmani –

## N

* 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
* †Nanno
** †Nanno aulema
* †Nasutimena
** †Nasutimena fluctuosa – or unidentified comparable form
* †Nematopora
** †Nematopora conferta
** †Nematopora consueta
** †Nematopora ovalis
* †Neobothriocidaris
** †Neobothriocidaris templetoni
* †Neocoleodus
* †Neopanderodus
* †Ningulella
** †Ningulella paucisulcata
* †Nodambichilina
** †Nodambichilina symmetrica
* †Nuculites –

## O

* 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
* †Oepikina
** †Oepikina inquassa
** †Oepikina minnesotensis
* †Oistodus
** †Oistodus abundans
** †Oistodus venustus
* †Omospira
** †Omospira laticincta
** †Omospira trentonensis
* †Oneotodus
** †Oneotodus ovatus
* †Onniella
** †Onniella porrecta
** †Onniella quadrata
* †Onoceras
** †Onoceras abruptum
** †Onoceras douglassi
** †Onoceras tetreauvillense
* †Ophileta
* †Ophiletina
** †Ophiletina angularis
** †Ophiletina fausta
** †Ophiletina sublaxa
* †Opikatia
** †Opikatia emaciata
** †Opikatia rotunda
* †Orbiculoidea
** †Orbiculoidea lamellosa – or unidentified comparable form
** †Orbiculoidea pelopea
* †Ormoceras – tentative report
** †Ormoceras maquoketense
* †Orthoceras
** †Orthoceras beltrami
** †Orthoceras minnesotense
* †Orthodesma
** †Orthodesma canaliculatum
** †Orthodesma caniculatum
** †Orthodesma litoralis
* †Orthograptus
* †Oulodus
** †Oulodus serratus
* †Oxoplecia
** †Oxoplecia ulrichi
* †Ozarkodina
** †Ozarkodina concinna
** †Ozarkodina delecta
** †Ozarkodina raaschi –

## P

* 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
* †Pachydictya
** †Pachydictya elegans
* †Pachyglossella
** †Pachyglossella elderi
** †Pachyglossella riciniformis
* †Palaeocrinus
** †Palaeocrinus angulatus
* †Palaeoglossa
** †Palaeoglossa hurlburti
* †Palaeoneilo
* †Paleocrinus
** †Paleocrinus angulatus
* †Panderodus
** †Panderodus feulneri
** †Panderodus gracilis
** †Panderodus panderi
* †Parabolbina
** †Parabolbina antecedans
** †Parabolbina carinifera
** †Parabolbina staufferi
* †Paraliospira
** †Paraliospira abrupta
** †Paraliospira supracingulata
* †Paraschmidtella
** †Paraschmidtella irregularis
** †Paraschmidtella uphami
* †Parastrophina
** †Parastrophina berensis
** †Parastrophina bernensis
** †Parastrophina rotundiformis
* †Parenthatia
** †Parenthatia camerata
** †Parenthatia punctata
* †Parschmidtella
** †Parschmidtella uphami
* †Paucicrura
** †Paucicrura corpulenta
** †Paucicrura rogata
* †Paupospira
** †Paupospira burginensis
** †Paupospira elevata
** †Paupospira oweni
** †Paupospira sumnerensis
* †Pedomphalella
** †Pedomphalella intermedia
** †Pedomphalella subovata
* †Periglyptocrinus
** †Periglyptocrinus spinuliferus
* †Periodon
** †Periodon grandis
* †Petrocrania
** †Petrocrania halli
** †Petrocrania trentonensis
* †Phialaspongia – type locality for genus
** †Phialaspongia fossa – type locality for species
* †Phragmodus
** †Phragmodus cognitus
** †Phragmodus inflexus
** †Phragmodus undatus
* †Phragmolites
** †Phragmolites compressus
** †Phragmolites dyeri
** †Phragmolites fimbriata
** †Phragmolites obliquus
** †Phragmolites triangularis
* †Phyllodictya
** †Phyllodictya varia
* †Pinodema
** †Pinodema conradi
* †Pionodema
** †Pionodema circularis
** †Pionodema subaequata
* Fossilized shell of the Ordovician brachiopod Plaesiomys †Plaesiomys
** †Plaesiomys meedsi
** †Plaesiomys proavitus
** †Plaesiomys subquadrata
* †Platystrophia
** †Platystrophia amoena
** †Platystrophia biforata
** †Platystrophia extensa – tentative report
** †Platystrophia trentonensis
* †Plectoceras
** †Plectoceras occidentale
** †Plectoceras robertsoni
* †Plectodina
** †Plectodina aculeata
** †Plectodina tenuis
* †Plectorthis
** †Plectorthis plicatella
* †Plethocardia
** †Plethocardia suberecta
* †Plethospira
** †Plethospira cannonensis – type locality for species
** †Plethospira cassina
* Fossil of the Late Ordovician cystoid echinoderm Pleurocystites †Pleurocystites
** †Pleurocystites squamosus
* †Polygammoceras
** †Polygammoceras prestonense
* †Polygnathus
** †Polygnathus curtigladius
** †Polygnathus intermedius
** †Polygnathus linguiformis
** †Polygnathus parawebbi
* †Polygrammoceras
** †Polygrammoceras prestonense
* †Polyplacognathus
** †Polyplacognathus ramosus
* †Porocrinus
** †Porocrinus elegans
** †Porocrinus fayettensis
** †Porocrinus pentagonius
** †Porocrinus smithi – or unidentified related form
* †Praepleurocystis
* †Prasopora
** †Prasopora insularis
* †Primitella
** †Primitella constricta
** †Primitella plattevillensis
* †Primitia
** †Primitia cannonensis – type locality for species
** †Primitia gibbera
** †Primitia mammata
** †Primitia spinata
** †Primitia tumidula
* †Primitiella
** †Primitiella bellevuensis
** †Primitiella carlei
** †Primitiella constricta
** †Primitiella milleri
** †Primitiella plattevillensis
* †Primitiopsis – tentative report
** †Primitiopsis bella
* †Probillingsites
** †Probillingsites milleri
** †Probillingsites pronis
** †Probillingsites welleri
* †Prolobella
* †Promopalaeaster
** †Promopalaeaster wilsoni
* †Proplina
** †Proplina convexum – type locality for species
** †Proplina cornutaformis – type locality for species
** †Proplina corpulentum – type locality for species
** †Proplina extensum – type locality for species
* †Prosaukia
** †Prosaukia ambigua
** †Prosaukia misa
* †Proteroconus
** †Proteroconus capuloides – type locality for species
* †Protopanderodus
** †Protopanderodus liripipus
* †Pseudagnostus
** †Pseudagnostus josephus
* †Pseudolingula
** †Pseudolingula eva
** †Pseudolingula iowensis
* †Pseudoprimitella
** †Pseudoprimitella unicornis
* †Pseudulrichia
** †Pseudulrichia simplex
* †Psuedulrichia
** †Psuedulrichia simplex
* †Pterinea
* †Pterotheca
** †Pterotheca attenuata
* †Pterygometopus
** †Pterygometopus sclerops – or unidentified comparable form
* †Ptiloconus
* †Ptilodictya – tentative report
* †Ptychaspis
** †Ptychaspis granulosa
** †Ptychaspis miniscaensis
** †Ptychaspis striata
** †Ptychaspis tuberosa
* †Ptychocrinus
* †Punctaparchites
** †Punctaparchites rugosus
** †Punctaparchites splendens
* †Pycnocrinus
** †Pycnocrinus gerki
** †Pycnocrinus multibrachialis
** †Pycnocrinus sardesoni
* †Pyrgocystis
** †Pyrgocystis sardesoni –

## 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
* †Quasibollia –
** †Quasibollia persulcata
** †Quasibollia ridicula
* †Quienquecaudex
** †Quienquecaudex springeri –

## 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
* †Rafinesquina –
** †Rafinesquina deltoidea
** †Rafinesquina nitans
** †Rafinesquina trentonensis
* †Raphistoma
** †Raphistoma shakopeense – type locality for species
* †Raphistomina
** †Raphistomina lapicida
** †Raphistomina rugata
* †Raymondatia
** †Raymondatia goniglypta
* †Redpathoceras – tentative report
* †Reedsoceras
** †Reedsoceras macrostomum
* †Reteocrinus
** †Reteocrinus rocktonensis
** †Reteocrinus spinosus
* †Rhaphanocrinus
** †Rhaphanocrinus buckleyi
* †Rhaphistomina
** †Rhaphistomina rugata
* †Rhinidictya
* †Rhynchotrema
** †Rhynchotrema ainsliei
** †Rhynchotrema laticosta
** †Rhynchotrema wisconsinense
* †Rhytimya
* †Richardsonoceras
** †Richardsonoceras beloitense
** †Richardsonoceras clarkei
** †Richardsonoceras romingeri
** †Richardsonoceras scofieldi
** †Richardsonoceras simplex
* †Rigidella
** †Rigidella cannonensis – type locality for species
* †Rioceras
** †Rioceras consuetum – tentative report
* †Rosticellula
** †Rosticellula colei
* Rostricellula
** †Rostricellula minnesotensis –

## 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
* †Saccelatia
** †Saccelatia angularis
** †Saccelatia arcuamuralis
** †Saccelatia arrecta
** †Saccelatia bullata
** †Saccelatia cletifera
* †Saffordia
* †Salpingostoma
** †Salpingostoma buelli
** †Salpingostoma imbricata
** †Salpingostoma sculptilis
* †Saratogia
** †Saratogia hamula
* †Scaevogyra
** †Scaevogyra swezeyi – type locality for species
* †Scalenocystites
** †Scalenocystites strimplei
* †Scalites
** †Scalites peracutum
* Fossils of the Cambrian mollusc Scenella †Scenella
** †Scenella compressa
** †Scenella obtusa
* †Sceptaspis
** †Sceptaspis lincolnensis
* †Schizambon
* †Schizocrania
** †Schizocrania filosa
* †Schmidtella
** †Schmidtella affinis
** †Schmidtella brevis
** †Schmidtella lacunosa
* †Schuchertia
* †Schuchertoceras
** †Schuchertoceras thomasi
* †Scofieldia
** †Scofieldia bilateralis
* †Scofieldoceras
** †Scofieldoceras depressum
** †Scofieldoceras shumardi
* †Scyphiodus
** †Scyphiodus primus
* †Similodonta
* †Simulites
** †Simulites concinnus
* †Sinuites
** †Sinuites cancellatus
** †Sinuites pervoluta
** †Sinuites rectangularis
** †Sinuites subcompressa – type locality for species
* †Sivertsia
* †Skenidioides
** †Skenidioides anthonense
* †Sowerbyella
** †Sowerbyella curdsvillensis
** †Sowerbyella minnesotensis
* †Spatiopora
** †Spatiopora lineata
* †Sphenolium
* †Sphenosphaera
** †Sphenosphaera platystoma
** †Sphenosphaera rogersensis
* †Spyroceras
** †Spyroceras cylindratum
** †Spyroceras lesueuri
** †Spyroceras perroti – or unidentified comparable form
** †Spyroceras scofieldi
* †Staufferella
** †Staufferella falcata
* †Staufferoceras
** †Staufferoceras featherstonhaughi
* †Stereoconus
** †Stereoconus gracilis
* †Stictopora
** †Stictopora dumosa
** †Stictopora exigua
** †Stictopora lita
** †Stictopora minima
** †Stictopora mutabilis
** †Stictopora neglecta – or unidentified comparable form
** †Stictopora paupera
* †Stictoporella
** †Stictoporella angularis
** †Stictoporella cribrosa
** †Stictoporella frondifera
** †Stictoporella gracilis
* †Stigmacephalus
** †Stigmacephalus flexifrons
* †Stigmaspis
** †Stigmaspis hudsonensis
* †Stigmatella
** †Stigmatella claviformis
* †Strepsodiscus
** †Strepsodiscus franconiensis – type locality for species
** †Strepsodiscus strongi
* †Streptelasma
** †Streptelasma corniculum
* Fossilized shell of the Ordovician-Silurian brachiopod Strophomena †Strophomena
** †Strophomena billingsi
** †Strophomena filitexta
** †Strophomena incurvata
** †Strophomena occidentalis
** †Strophomena planodorsata
** †Strophomena plattinensis – or unidentified comparable form
** †Strophomena septata
** †Strophomena trilobata
** †Strophomena trilobita
* †Stylocyrtoceras
** †Stylocyrtoceras tantillum – type locality for species
* †Subulites
** †Subulites conradi
** †Subulites dixonenesis
** †Subulites elongatus
** †Subulites pergracilis
** †Subulites regularis
* †Sygcaulocrinus
** †Sygcaulocrinus typus –

## 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
* †Tanaocystis
* †Tancrediopsis
* †Technophorus
** †Technophorus divaricatus
* †Teichertoceras
** †Teichertoceras husseyi – or unidentified comparable form
* †Tetradella
** †Tetradella ellipsilira
** †Tetradella subquadrans
** †Tetradella ulrichi
* †Tetranota
** †Tetranota bidorsata
** †Tetranota macra
** †Tetranota obsoleta
** †Tetranota sexcarinata
** †Tetranota wisconsinensis
* †Tetraprioniodus
** †Tetraprioniodus breviconus
* †Thaleops
** †Thaleops ovata
* †Thomasatia
** †Thomasatia falcicosta
* †Thuroholia
** †Thuroholia cribriformis
** †Thuroholia croneisi
* †Traskocrinus
** †Traskocrinus mahlburgi
* †Trematis
** †Trematis huronensis
* †Trematopora
** †Trematopora primigenia
* †Trichinocrinus – or unidentified related form
* †Triconodella
** †Triconodella flexa
* †Trigrammaria
** †Trigrammaria winchelli
* †Tripteroceras
** †Tripteroceras oweni
** †Tripteroceras planoconvexum
** †Tripteroceras scofieldi
* †Trochonema
** †Trochonema altum
** †Trochonema beachi
** †Trochonema beloitense
** †Trochonema fragile
** †Trochonema retrorsum
** †Trochonema rugosa
** †Trochonema subcrassum
** †Trochonema umbilicata
** †Trochonema vagrans
* Illustration of a fossilized shell in multiple views of the Silurian monoplacophoran mollusc Tryblidium reticulatum. Head region is to the left. †Tryblidium
** †Tryblidium exserta –

## 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
* †Ulrichaster –
** †Ulrichaster ulrichi
* †Ulrichia
** †Ulrichia saccula
* †Ulrichoceras
** †Ulrichoceras beloitense
* Fossil of the Ordovician-Devonian sea star Urasterella †Urasterella
* †Valcouroceras
* †Vanuxemia
** †Vanuxemia dixonensis
* †Vellamo
** †Vellamo americana –

## 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
* †Westonoceras
** †Westonoceras iowense
** †Westonoceras minnesotense
* †Whiteavesia
* †Whiteavesites
* †Whitfieldoceras
** †Whitfieldoceras clarkei
** †Whitfieldoceras exiguum – or unidentified comparable form
** †Whitfieldoceras minimum
** †Whitfieldoceras mumiaforme
* †Wilbernia
** †Wilbernia pero
* †Willmanocystis
** †Willmanocystis denticulatus
* †Winchellatia
** †Winchellatia ceratopea – type locality for species
** †Winchellatia lansingensis
** †Winchellatia longispina
** †Winchellatia minnesotensis
** †Winchellatia minnsotensis –

## 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
* †Zittelloceras
** †Zittelloceras beloitense
** †Zittelloceras brevicurvatum
** †Zittelloceras clarkeanum
** †Zittelloceras percurvatum
** †Zittelloceras scofieldi
** †Zittelloceras tenuistriatum
* †Zygobolboides
** †Zygobolboides calvini
** †Zygobolboides grafensis
** †Zygobolboides iowensis
** †Zygobolboides thomasi
* †Zygospira
** †Zygospira lebanonensis
** †Zygospira modesta
** †Zygospira plinthii – type locality for species
** †Zygospira uphami