PBDB Taxon

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Cyclostomi

Taxonomy

Cyclostomi was named by Duméril (1806).

It was reranked as the class Cyclostomi by Huang (2024).

It was assigned to Vertebrata by Miyashita et al. (2019); and to Chordata by Huang (2024).

Subtaxa

Cyclostomata (syn. Marsipobranchii), Squirmarius

Entered

by M. Uhen on 2019-04-01; modified by M. Uhen on 2019-04-02

Synonymy list

Year	Name and author
1806	Cyclostomi Duméril p. 2147
2019	Cyclostomi Miyashita et al. p. 2147
2024	Cyclostomi Huang p. 2259

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Rank	Name	Author
kingdom	Animalia	()
—	Bilateria
—	Eubilateria	Ax 1987
—	Deuterostomia

Rank	Name	Author
phylum	Chordata	Haeckel 1874
class	Cyclostomi	(Duméril 1806)
class	Cyclostomi	(Duméril 1806)

If no rank is listed, the taxon is considered an unranked clade in modern classifications. Ranks may be repeated or presented in the wrong order because authors working on different parts of the classification may disagree about how to rank taxa.

Cl. †Cyclostomi Duméril 1806

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Subcl. Cyclostomata Richards

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Cl. †Anaspida Traquair

Or. †Anaspidiformes

Fm. †Pharyngolepididae Kiær 1924

G. †Pharyngolepis Kiaer 1911

Fm. †Pterygolepididae Obruchev 1964

G. †Pterygolepis Kiaer 1911

Fm. †Ramsaasalepididae Blom et al. 2003

G. †Ramsaasalepis Blom and Marss 2003

Fm. †Septentrioniidae Blom et al. 2002

G. †Septentrionia Blom et al. 2001

Fm. †Tahulalepididae Blom et al. 2002

G. †Tahulalepis Blom et al. 2001

Invalid names: Rhyncholepididae Kiaer 1924 [empty]

Or. Birkeniida Berg 1937

G. †Cowielepis Blom 2008

†Cowielepis ritchiei Blom 2008

Or. †Birkeniiformes

Fm. †Birkeniidae Traquair 1899

G. †Birkenia

G. †Ctenopleuron Mathew 1907

G. †Kerreralepis BLOM 2012

G. †Rhyncholepis Kiaer 1911

G. †Conopiscius

Or. †Endeiolepidiformes

Fm. †Endeiolepididae Stensiö 1939

G. †Endeiolepis Stensiö 1939

Or. †Conodontophorida Eichenberg 1930

G. †Algherella

G. †Alternognathus

G. †Amydrotaxis

G. †Angulodus

G. †Axiothea

G. †Caenodontus

G. †Cambropustula Müller and Hinz 1991

G. †Coelocerodontus Ethington 1959

†Coelocerodontus trigonius Ethington 1959

Cl. †Conodonta Pander 1856 [conodont]

G. †Acodina Stauffer

†Acodina cuspidata Stauffer 1940

†Acodina inoptinata Stauffer 1938

Invalid names: Acodina concava Stauffer 1940 [synonym], Acodina lirata Stauffer 1940 [synonym], Acodina ursa Stauffer 1940 [synonym]

G. †Aldridgeodus Calner et al. 2008

†Aldridgeodus minimus Calner et al. 2008

G. †Aldridgeognathus Miller et al. 2017

†Aldridgeognathus manniki Miller et al. 2017

G. †Ancidontus Chen and Gong 1986

G. †Ancyrogondolella Budurov 1972

†Ancyrogondolella triangularis Budurov 1972

G. †Apteracontiodus Bauer 2010

†Apteracontiodus carinatus Stouge 1984

Or. †Belodellida Sweet 1988

Fm. †Ansellidae Fåhræus and Hunter 1985

Fm. †Belodellidae Khodalevich and Tschernich 1973

G. †Besselodus Aldridge 1982

Fm. †Dapsilodontidae Sweet 1988

G. †Branmehla Haas 1959

G. †Chengyuania Kozur 1994

Invalid names: Pseudogondolella Kozur 1990 [replaced]

Fm. †Coleodontidae Branson and Mehl 1944

G. †Archaeognathus Cullison 1938

G. †Coleodus Branson and Mehl 1933

G. †Mixoconus Sweet 1955

G. †Neocoleodus Branson and Mehl 1933

G. †Stereoconus Branson and Mehl 1933

Invalid names: Archaeognathidae Miller 1969 [synonym]

G. †Cooperignathus Zhen et al. 2003

G. †Costiconus Rasmussen 2001

†Costiconus costatus Dzik 1976

†Costiconus ethingtoni Fåhræus 1966

†Costiconus iniquus Viira 1974

G. †Dasytodus Chen and Gong 1986

†Dasytodus transmutatus Xu and Xiang 1983

G. †Diaphanodus Bagnoli 1987

†Diaphanodus compressus Chen and Gong 1986

Invalid names: Stenodontus Chen and Gong 1986 [replaced], Vanwamelodus Apollonov 1984 [replaced]

G. †Dischidognathus

†Dischidognathus primus Ethington and Clark 1982

G. †Dolborodina Moskalenko 2003

†Dolborodina juktaliensis Moskalenko 1973

G. †Enantiognathus Mosher and Clark 1965

Invalid names: Enantiognathus ziegleri Diebel 1956 [nomen dubium]

G. †Eofalodus Harris 1962

Infracl. †Euconodonta Janvier 1997

Or. †Proconodontida Sweet 1988

G. †Fahraeosodus Stouge and Bagnoli 1988

G. †Falcodus Huddle 1934

†Falcodus secundus Youngquist 1945

†Falcodus ultimus Branson and Mehl 1934

G. †Gagievodus Baranov and Al'khovik 2003

G. †Gobduntaulepis Doweld 2014

†Gobduntaulepis bispinatus Pianovskij 1989

Invalid names: Acantholepis Pianovskij 1989 [replaced]

G. †Heterdontoides

†Hindeodella (Metaprioniodus) andrusovi koeveskalensis Kozur and Mostler 1972

G. †Iowagnathus Liu et al. 2017

†Iowagnathus grandis Liu et al. 2017

G. †Llandoverygnathus Walliser 1972

G. †Lundodus Bagnoli and Stouge 1997

†Lundodus gladiatus Lindström 1955

G. †Minimodus Rasmussen 2001

†Minimodus maocaopus Zhang 1998

G. †Nasusgnathus Ni 1983

†Nasusgnathus dolonus An 1981

G. †Noixodontus McCracken and Barnes 1982

G. †Omanognathus Miller et al. 2017

†Omanognathus daiqaensis Miller et al. 2017

G. †Oslodus Zhang 1998

†Oslodus semisymmetricus Hamar 1966

Or. †Ozarkodinida Dzik 1976

Fm. †Anchignathodontidae Clark 1972

Fm. †Elictognathidae Austin and Rhodes 1981

Fm. †Ellisoniidae Clark 1972

G. †Gamachignathus

Fm. †Gondolellidae Lindstrom 1970

Invalid names: Xaniognathidae Sweet 1981 [synonym]

Superfm. †Gondolelloidea Lindstrom 1970

Fm. †Idiognathodontidae Harris and Hollingsworth 1933

Fm. †Kockelellidae Klapper 1981

G. †Microzarkodina Lindström 1971

Subor. †Ozarkodinina Dzik 1976

Fm. †Palmatolepididae Sweet 1988

G. †Periodon Hadding 1913

Invalid names: Loxognathus Graves and Ellison 1941 [synonym]

G. †Plectodina

Fm. †Pterospathodontidae Cooper 1977

Fm. †Spathognathodontidae Hass 1959

Fm. †Spathognathodontodae Hass 1959

Fm. †Vjalovognathidae Yuan et al. 2016

Invalid names: Gondolellidea Lindstroem 1970 [empty]

G. †Palmatodella Bassler 1925

†Palmatodella paridens Huddle 1934

Or. †Panderodontida Sweet 1988

G. †Cristodus

G. †Loxodus Furnish 1938

Fm. †Panderodontidae Lindström 1970

G. †Thrincodus Bauer 1987

G. †Pandorinella Müller and Müller 1957

†Pandorinella insita Stauffer 1940

Or. †Paraconodontida Müller 1962

G. †Bengtsonella Müller and Hinz 1991

G. †Furnishina Müller 1959

Superfm. †Furnishinacea Müller 1981

G. †Hertzina Mueller 1959

G. †Muellerodus Miller 1980

G. †Nogamiconus Miller 1980

G. †Phakelodus Miller 1984

G. †Proacodus Müller 1959

G. †Problematoconites Mueller 1959

G. †Prooneotodus Mueller 1959

G. †Prosagittodontus Müller and Nogami 1971

G. †Serratocambria Müller and Hinz 1991

G. †Tarimspira Yue and Gao 1992

Invalid names: Fengzuella He and Yu 1992 [synonym]

G. †Trolmenia Müller and Hinz 1991

G. †Westergaardodina Müller 1959

Invalid names: Amphigeisinacea Clark et al. 1981 [empty]

G. †Parvigondolella Kozur and Mock 1972

†Parvigondolella andrusovi Kozur and Mock 1972

G. †Pollognathus Kozur and Mostler 1970

Or. †Polyplacognathida Stouge and Bagnoli 1999

Invalid names: Cahabagnathidae Stouge and Bagnoli 1999 [empty]

Or. †Prioniodontida Dzik 1976

Fm. †Acodontidae Dzik 1994

G. †Anticostiodus Zhang and Barnes 2000

Fm. †Balognathidae Hass 1959

Invalid names: Prioniodontidae Ulrich and Bassler 1926 [synonym]

Superfm. †Balognathoidea Hass 1959

Fm. †Cyrtoniodontidae Hass 1959

Fm. †Distomodontidae Klapper 1981

G. †Histiodella

Fm. †Multioistodontidae Harris 1964

G. †Oepikodus Lindström 1955

Fm. †Oistodontidae Lindström 1970

Fm. †Paracordylodontidae Bergström 1981

G. †Paracordylodus Lindström 1955

G. †Phragmodus Branson and Mehl 1933

Invalid names: Cyrtoniodus Stauffer 1935 [synonym]

Fm. †Plectodinidae Sweet 1988

Or. †Prioniodinida Sweet 1988

Subor. †Prioniodinina Sweet 1988

Superfm. †Prioniodontacea Bassler 1925

Fm. †Rhipidognathidae Lindström 1970

Fm. †Strachanognathidae Bergstrom 1981

Invalid names: Periodontidae Lindström 1970 [empty]

Or. †Protopanderodontida

Fm. †Acanthodontidae Lindström 1970

Fm. †Clavohamulidae Lindström 1970

Fm. †Cornuodontidae Stouge 1984

Fm. †Drepanoistodontidae Fahraeus and Nowlan 1978

Fm. †Oneotodontidae Miller 1980

Fm. †Protopanderodontidae Lindström 1970

Fm. †Serratognathidae Zhen et al. 2009

G. †Pseudobelodella Armstrong 1990

†Pseudobelodella silurica Armstrong 1990

G. †Rexroadus Zhang and Barnes 2002

†Rexroadus kentuckyensis Branson and Branson 1947

†Rexroadus nathani McCracken and Barnes 1981

G. †Rhynchognathodus Ethington 1959

G. †Rotundoconus An and Zhang 1983

G. †Sagittodontus Rhodes 1953

G. †Silurognathus Jeppsson 2005

†Silurognathus maximus Jeppsson 2005

G. †Spathognathodus Branson and Mehl 1941

†Spathognathodus asymmetricus Bischoff and Sannemann 1958

†Spathognathodus culminidirectus Scott 1961

†Spathognathodus dubius Ethington and Furnish 1962

†Spathognathodus fundamentus Walliser 1957

†Spathognathodus optimus Moskalenko 1966

†Spathognathodus stygius Flajs 1967

†Spathognathodus transitans Bischoff and Sannemann 1958

G. †Tardogondolella Kozur and Mostler 1971

†Tardogondolella postera Kozur and Mostler 1971

G. †Tokognathus Nieper 1969

G. †Trichonodella Branson and Branson 1947

†Trichonodella blanda Stauffer 1940

†Trichonodella inconstans Ziegler 1960

G. †Youngquistognathus Myshkina and Zhuravlev 2005

G. †Zygognathus Branson et al. 1951

†Zygognathus manifestus Moskalenko 1973

Invalid names: Amphigeisinidae Miller 1981 [empty], Euconodonta Müller and Hinz 1991 [empty], Euconodonta Müller and Hinz 1991 [empty], Hindeodella andrusovi Kozur and Mostler 1972 [nomen dubium], Nothognathella Branson and Mehl 1934 [nomen vanum], Polygnathida Barskov 1995 [empty]

G. †Declinognathodus Dunn 1966

†Declinognathodus noduliferus Ellison and Graves 1941

G. †Dentacodina

G. †Dichodella

†Dichodella exilis Serpagli 1967

Superfm. †Distacodontacea Bassler 1925

Fm. †Distacodidae Ulrich and Bassler 1926

G. †Distacodus Pander 1856

Invalid names: Distacodontidae Bassler 1925 [empty], Teridontidae Miller 1981 [empty], Ulrichodinidae Bergstrom 1981 [empty]

G. †Elsonella

G. †Embaysgnathus

G. †Eocarniodus Orchard 1980

†Eocarniodus gracilis Rhodes 1955

G. †Evencodus

G. †Exochognathus Pollock et al. 1970

†Exochognathus brassfieldensis Branson and Branson 1947

†Exochognathus expansus Nicoll and Rexroad 1969

G. †Fungulodus

G. †Geniculatus

Superfm. †Hibbardellacea Mueller 1956

Fm. †Hibbardellidae Müller 1956

G. †Delotaxis Klapper and Philip 1971

G. †Hindeodelloides

G. †Hindeodina

G. †Homoiranognathus

G. †Huddlella

G. †Istorinus Knüpfer 1967

†Istorinus erectus Knüpfer 1967

Invalid names: Istorinus disymmetricus Knüpfer 1967 [synonym], Istorinus humilis Knüpfer 1967 [synonym], Istorinus postdentatus Knüpfer 1967 [synonym], Istorinus recurvus Knüpfer 1967 [synonym]

G. †Laterignathus

G. †Leutorhinion

Fm. †Mestognathidae Austin and Rhodes 1981

G. †Mestognathus Bischoff

G. †Mitrellotaxis

G. †Neocavitella

G. †Norigondolella

G. †Oligodus

G. †Ozarcodina Walliser

Superfm. †Panderodontacea Lindstrom 1970

Invalid names: Scolopodontidae Bergstrom 1981 [empty]

G. †Paraprionodus Ethington and Clark 1982