PBDB Taxon

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Unionata

Bivalvia

Taxonomy

Unionata was named by Gray (1854). It is extant.

It was assigned to Unioni by Carter et al. (2011).

Subtaxa

Trigoniida, Unionida

Synonymy list

Year	Name and author
1854	Unionata Gray
2011	Unionata Carter et al. p. 11

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Rank	Name	Author
kingdom	Animalia	()
—	Bilateria
—	Eubilateria	Ax 1987
—	Protostomia
—	Spiralia
superphylum	Lophotrochozoa
phylum	Mollusca
class	Bivalvia

Rank	Name	Author
—	Eubivalvia
subclass	Autobranchia	(Groblen 1894)
infraclass	Heteroconchia	(Gray 1854)
—	Uniomorphi	Gray 1854
—	Unioni	Gray 1854
—	Unionata	Gray 1854
—	Unionata	Gray 1854

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.

Unr. Unionata Gray 1854

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Or. Trigoniida Dall 1889

G. †Andivaugonia

G. †Antutitrigonia

G. †Arabitrigonia

G. †Columbitrigonia

G. †Dampietrigonia

G. †Gobiella

G. †Heslingtonia Fleming 1987

G. †Kupenga

G. †Litotrigonia

G. †Macrotrigonia Camacho and Olivero 1985

G. †Mediterraneotrigonia

Superfm. †Myophorelloidea Kobayashi 1954

Unr. †Megatrigonioidae van Hoepen 1929

Unr. †Megatrigoniitae van Hoepen 1929

Fm. †Megatrigoniidae van Hoepen 1929

Invalid names: Anditrigoniidae Leanza 1993 [synonym]

Invalid names: Iotrigoniidae Saveliev 1958 [empty]

Unr. †Rutitrigoniitae van Hoepen 1929

Invalid names: Rutitrigoniidae van Hoepen 1929 [empty]

Unr. †Myophorelloidae Kobayashi 1954

Fm. †Buchotrigoniidae Leanza 1993

Subfm. †Syrotrigoniinae Perez and Reyes 1997

Invalid names: Buchotrigoniinae Leanza 1993 [empty]

Fm. †Laevitrigoniidae Saveliev 1958

Subfm. †Frenguelliellinae Nakano 1960

Subfm. †Laevitrigoniinae Saveliev 1958

Fm. †Myophorellidae Kobayashi 1954

Subfm. †Myophorellinae Kobayashi 1954

Subfm. †Steinmanellinae Cooper 1991

Subfm. †Vaugoniinae Kobayashi 1954

Fm. †Steinmanellidae Cooper 1991

Subfm. †Yaadiinae Cooper and Leanza 2017

G. †Louella Cooper and Leanza 2017

G. †Popenoella Cooper and Leanza 2017

Invalid names: Packardella Kobayashi and Amano 1955 [synonym]

G. †Tashiroella Cooper and Leanza 2017

G. †Yaadia Crickmay 1930

G. †Yeharella Kobayashi and Amano 1955

Invalid names: Frenguelliellidae Nakano 1960 [empty]

G. †Nakanotrigonia

G. †Neuquenenitrigonia

G. †Paranditrigonia

G. †Procostaria

Superfm. †Pseudocardinioidea Martinson 1961

Fm. †Pseudocardiniidae Martinson 1961

G. †Apseudocardinia Liu and Zhu 1978

†Apseudocardinia hupehensis Grabau 1923

†Apseudocardinia sichuanensis Liu and Zhu 1978

G. †Hamiconcha Huang et al. 1981

G. †Jiangxiella Liu 1968

†Jiangxiella datianensis Liu 1976

†Jiangxiella elliptica Liu 1976

†Jiangxiella plana Liu 1976

†Jiangxiella subovata Liu 1976

G. †Pseudocardinia Martinson 1959

G. †Xinjiangconcha Wei 1984

†Xinjiangconcha lingulaiformis Wei 1984

G. †Xinyuella Chen and Xu 1980

†Xinyuella liuyangensis Gu and Liu 1976

Fm. †Utschamiellidae Kolesnikov 1977

G. †Utschamiella Ragozin 1937

G. †Skwarkoella

Subor. Trigoniina Dall 1899

Superfm. Trigoniacea Lamarck 1819

G. †Anopisthodon Philippi 1899

†Anopisthodon obesa Philippi 1847

G. †Aulacopleurum Philippi 1899

Superfm. Trigonioidea Lamarck 1819

Fm. †Costatoriidae Newell and Boyd 1975

G. †Procostatoria Newell and Boyd 1975

†Procostatoria cooperi Newell and Boyd 1975

†Procostatoria gloveri Newell and Boyd 1975

†Procostatoria sexradiata Branson 1930

Fm. †Eoschizodidae Newell and Boyd 1975

G. †Eoschizodus Cox 1951

†Eoschizodus hispanicus Amler 2010

†Eoschizodus truncatus Goldfuss 1837

Fm. †Groeberellidae Pérez et al. 1995

G. †Groeberella Leanza 1993

†Groeberella neuquensis Groeber 1924

Fm. †Ladinomyidae Prinoth and Posenato 2023

G. †Ladinomya Prinoth and Posenato 2023

†Ladinomya fosteri Prinoth and Posenato 2023

Fm. †Myophoriidae Bronn 1847

G. †Acanomyphoria Guo 1985

†Acanomyphoria tuberosa Guo 1985

G. †Amlerella Franke 2016

†Amlerella dahmeri Drevermann 1907

†Amlerella peregrina Beushausen 1895

G. †Atalantia Termier and Verriez 1974

†Atalantia trigonioides Termier 1974

G. †Baidiostraca Guo 1988

†Baidiostraca aberrans Guo 1988

G. †Caledogonia Freneix and Avias 1977

†Caledogonia globosa Freneix and Avias 1977

G. †Costatoria Waagen 1907

†Costatoria costata Zenker 1833

†Costatoria fallax Seebach 1833

†Costatoria inaequicostata Klipstein 1843

†Costatoria katsurensis Nakazawa 1967

†Costatoria kobayashii Kambe 1951

†Costatoria melanesiana Skwarko 1967

†Costatoria nazeensis Guo 1985

†Costatoria omanica Diener 1908

†Costatoria subrotunda Bittner 1901

†Costatoria vestitaeformis Krumbeck 1923

†Costatoria whateleyae Buch 1845

†Myophoria (Costatoria) goldfussi Alberti 1830

†Myophoria (Costatoria) kweichowensis Ku 1957

†Myophoria (Costatoria) mansuyi Reed 1927

†Myophoria (Costatoria) minor Chen 1976

†Myophoria (Costatoria) napangensis Healey 1908

†Myophoria (Costatoria) nuitoensis Vukhuc 1965

†Myophoria (Costatoria) radiata Loczy 1899

†Myophoria (Costatoria) submultistriata Chen 1976

†Myophoria (Costatoria) szechenyii Loczy 1899

G. †Dolabra M'Coy 1844

†Dolabra arcina Waagen 1881

†Dolabra unilateralis Sowerby 1840

Invalid names: Dolabra condrusorum Beushausen 1895 [synonym]

G. †Elegantinia Waagen 1907

†Elegantinia elegans Dunker 1849

†Elegantinia lijiangensis Guo 1985

†Elegantinia paullorum Boyd and Newell 1997

†Myophoria (Elegantinia) grahami McLearn 1941

†Myophoria (Elegantinia) venusta Chen 1976

Invalid names: Lyriomyophoria Kobayashi 1954 [objective synonym]

G. †Erugonia Newton et al. 1987

†Erugonia canyonensis Newton et al. 1987

G. †Gruenewaldia von Wöhrmann 1889

†Gruenewaldia decussata Munster 1838

†Gruenewaldia iranica Hautmann 2001

†Gruenewaldia magna Hautmann 2001

†Gruenewaldia woehrmanni Bittner 1895

G. †Guizhoumyophoria Fang 2009

†Guizhoumyophoria quadrata Yin 1974

Invalid names: Quadratia Yin 1974 [replaced]

G. †Hefteria

G. †Heminajas Wöhrmann 1891

†Heminajas balatonis Frech 1905

†Heminajas fissidentata von Wöhrmann 1889

†Heminajas fornulata Chen 1976

†Heminajas geyeri Waagen 1907

†Heminajas haastiana Wilckens 1918

†Heminajas qinghaiensis Lu 1981

†Heminajas woehrmanni Waagen 1907

G. †Myophoria Bronn 1834

Subg. †Myophoria (Rhenania) Waagen 1907

Subg. †Myophoria (Tropiphora) Waagen 1907

†Myophoria acuticostata Broili 1904

†Myophoria adornata McLearn 1942

†Myophoria ambilineata White 1877

†Myophoria beringiana Smith 1927

†Myophoria bittneri Newton 1923

†Myophoria blainvillei Klipstein 1843

†Myophoria blakei Cox 1932

†Myophoria brockensis Smith 1927

†Myophoria cairnesi McLearn 1942

†Myophoria chenopus Laube 1865

†Myophoria costulata Bittner 1895

†Myophoria coxi Awad 1945

†Myophoria ebbae Isberg 1934

†Myophoria elliptica Ogilvie Gordon 1927

†Myophoria germanica Hohenstein 1914

†Myophoria goldfussi Alberti 1834

†Myophoria harpa Munster 1837

†Myophoria heslingtonensis Trechmann 1917

†Myophoria humboldtensis Smith 1927

†Myophoria incurvata Seebach 1867

†Myophoria inflata Emmrich 1853

†Myophoria intermedia Schauroth 1857

†Myophoria kefersteini Münster 1828

†Myophoria kokeni Bittner 1895

†Myophoria kuuoruensis Skwarko 1967

†Myophoria liasica Stoppani 1857

†Myophoria maxima Krumbeck 1923

†Myophoria mexicana de Cserna 1961

†Myophoria nifukokoensis Krumbeck 1924

†Myophoria ornata Münster 1841

†Myophoria picta Lepsius 1878

†Myophoria proharpa Frech 1912

†Myophoria reziae Stoppani 1865

†Myophoria solitaria Bittner 1895

†Myophoria staggi Skwarko 1967

†Myophoria stenonis Stoppani 1865

†Myophoria subtrigonata Airaghi 1907

†Myophoria subvestita Krumbeck 1913

†Myophoria timorensis Krumbeck 1924

†Myophoria transversa Bornemann 1856

†Myophoria vestita Alberti 1864

†Myophoria volzi Frech 1912

†Myophoria vulgaris von Schlotheim 1820

†Myophoria zeballos McLearn 1942

Invalid names: Trigonellites von Schlotheim 1820 [synonym]

G. †Neoschizodus Giebel 1855

†Myophoria (Neoschizodus) kreitneri Loczy 1899

Subg. †Neoschizodus (Leviconcha) Waagen 1907

Subg. †Neoschizodus (Okunominetania) Ichikawa 1949

†Neoschizodus cardissoides Ziethen 1830

†Neoschizodus elongatus Boyd and Newell 1997

†Neoschizodus elongatus Philippi 1898

†Neoschizodus elongatus Giebel 1856

†Neoschizodus hubeiensis Zhang 1977

†Neoschizodus kitakamiensis Nakazawa and Newell 1968

†Neoschizodus kobayashii Ichikawa 1951

†Neoschizodus kolymensis Bychkov et al. 1976

†Neoschizodus laevigatus Ziethen 1830

†Neoschizodus mongumensis Skwarko 1967

†Neoschizodus orbicularis Bronn 1837

†Neoschizodus ovatus Goldfuss 1838

†Neoschizodus permicus Nakazawa 1960

†Neoschizodus praeorbicularis Bittner 1901

†Neoschizodus thaynesianus Newell and Boyd 1975

G. †Paraschizodus Newell and Boyd 1975

†Paraschizodus elongatus Newell and Boyd 1975

†Paraschizodus rothi Newell and Boyd 1975

G. †Rhenania Waagen 1907

Subg. †Rhenania (Dianorhenania) Guo 1985

G. †Rhenanomya LaRoque 1969

†Rhenanomya crassa Solle 1956

†Rhenanomya tumida Fuchs 1915

G. †Toechomya

G. †Trionychodia Guo 1988

†Trionychodia bella Guo 1988

G. †Yangella Liu and Gu 1988

†Yangella cuneatiformis Liu and Gu 1988

Invalid names: Cytherodontidae Miller [synonym], Gruenewaldiidae Cooper 1991 [synonym]

Fm. †Prosogyrotrigoniidae Kobayashi 1954

Subfm. †Praegoniinae Fleming 1962

G. †Agonisca Fleming 1963

G. †Praegonia Fleming 1962

Subfm. †Prosogyrotrigoniinae Kobayashi 1954

G. †Prosogyrotrigonia Krumbeck 1924

Fm. †Scaphellinidae Newell and Ciriacks 1962

G. †Scaphellina Newell and Ciriacks 1962

†Scaphellina concinna Branson 1930

Invalid names: Scaphellina bradyi Newell and Ciriacks 1962 [synonym], Scaphellina phosphoriensis Branson 1930 [synonym]

†Scaphellina praeobscurus Guskov 1984

Fm. †Schizodidae Newell and Boyd 1975

Subfm. †Eoastartinae Newell and Boyd 1975

G. †Eoastarte Ciriacks 1963

G. †Kaibabella Chronic 1952

G. †Heteroschizodus Newell and Boyd 1975

†Heteroschizodus macomoides Newell and Boyd 1975

G. †Schizodus King 1844

†Schizodus acuminatus Hoare et al. 1978

†Schizodus affinis Herrick 1887

†Schizodus alpinus Hall 1858

†Schizodus altus Newell and Boyd 1975

†Schizodus amplus Meek and Worthen 1870

Invalid names: Schizodus mooresi Miller 1889 [synonym]

†Schizodus antiquus Hind 1898

†Schizodus australis Runnegar 1969

†Schizodus bifidus Ciriacks 1963

†Schizodus canalis Branson 1930

†Schizodus cardissa Waagen 1881

†Schizodus chemungensis Conrad 1842

†Schizodus chesterensis Meek and Worthen 1860

†Schizodus compressus Rogers 1900

†Schizodus compressus Waagen 1881

†Schizodus crespinae Dickins 1957

†Schizodus cuneatus Meek 1875

†Schizodus curtiformis Walcott 1884

†Schizodus curtus Meek and Worthen 1866

†Schizodus cycloliratus Harrington 1955

†Schizodus deparcus Walcott 1884

†Schizodus depressus Worthen 1884

Invalid names: Schizodus abruptus Girty 1915 [objective synonym], Schizodus circularis Worthen 1884 [synonym]

†Schizodus dianensis Guo 1985

†Schizodus dubiiformis Waagen 1881

†Schizodus ellioti Maxwell 1964

†Schizodus elongatus Grabau 1931

†Schizodus emarginatus Reed 1944

†Schizodus ferrieri Girty 1910

†Schizodus fitzroyensis Dickins 1963

†Schizodus globosus Maxwell 1964

†Schizodus guizhouensis Liu and Xu 1976

†Schizodus hedongensis Liu 1976

†Schizodus japonicus Hayasaka 1925

†Schizodus jiangbianensis Fang and Yin 1995

†Schizodus jiangheensis Lu 1986

†Schizodus jiangxiensis Li and Ding 1982

†Schizodus kennedyensis Dickins 1956

†Schizodus lianyuanensis Zhang 1977

†Schizodus lopingensis Kayser 1883

†Schizodus magnus Worthen 1884

†Schizodus meekanus Girty 1900

†Schizodus minutus Maxwell 1964

†Schizodus negrii Bittner 1892

†Schizodus obscurus Sowerby 1821

Invalid names: Axinus parvus Brown 1839 [synonym], Axinus pucillus Brown 1839 [synonym], Axinus undatus Brown 1839 [synonym], Lucina minima Brown 1839 [synonym]

†Schizodus occidentalis Reed 1930

†Schizodus ovatus Meek and Hayden 1858

†Schizodus parvulus Cooper 1953

†Schizodus pinguis Waagen 1881

†Schizodus pintoensis Walcott 1884

†Schizodus rhynchophorus Ponomarenko 2011

†Schizodus rossicus de Verneuil 1845

†Schizodus rotundatus Brown 1839

†Schizodus sandimanensis Dickins 1963

†Schizodus schlotheimi Geinitz 1841

†Schizodus securus Shumard 1859

†Schizodus sinensis Liu 1976

†Schizodus subcircularis Herrick 1887

†Schizodus subobscurus Licharew 1933

†Schizodus subovatus Ciriacks 1963

†Schizodus subquadratus Grabau 1931

†Schizodus supaiensis Winters 1963

†Schizodus texanus Clifton 1942

†Schizodus tibeticus Liu and Cui 1983

†Schizodus trigonalis Sayre 1930

†Schizodus truncatus King 1844

Invalid names: Schizodus dubius Schauroth 1856 [synonym]

†Schizodus tschernjaki Muromtseva 1974

†Schizodus ulrichi Worthen 1890

†Schizodus wheeleri Swallow 1863

†Schizodus wyomingensis Newell and Boyd 1975

†Schizodus xiangtanensis Fang 1987

Invalid names: Protoschizodus de Koninck 1885 [synonym], Schizodus jiaozishanensis Xu 1980 [nomen nudum], Schizodus qinglongensis Xu 1980 [nomen nudum]

G. †Silurozodus Liljedahl 1992

Fm. †Sinodorinae Pojeta and Zhang 1984

G. †Sinodora Pojeta and Zhang 1984

Invalid names: Schizodinae Newell and Boyd 1975 [empty]

Fm. Trigoniidae Lamarck 1819

G. †Actinotrigonia

G. †Asiatotrigonia Cox 1952

†Asiatotrigonia sultanuisi Archangelski 1916

G. †Buchotrigonia Dietrich 1938

Subg. †Buchotrigonia (Syrotrigonia) Cox 1952

†Buchotrigonia abrupta von Buch 1838

Invalid names: Trigonia humboldtii von Buch 1839 [synonym]

†Buchotrigonia cazadoriana Wilckens 1907

†Buchotrigonia collombi Vilanova 1863

†Buchotrigonia deshayesi Vilanova 1863

†Buchotrigonia flexicostata Fritzsche 1924

†Buchotrigonia inca Fritzsche 1924

†Buchotrigonia pizcuetana Vilanova 1863

†Buchotrigonia scheibei Dietrich 1938

G. †Climacotrigonia

G. †Eotrigonia Cossmann 1912

†Eotrigonia semiundulata Jenkins 1865

Invalid names: Trigonia subundulata Jenkins 1865 [synonym]

†Eotrigonia tubulifera Tate 1885

G. †Geratrigonia Kobayashi 1954

†Geratrigonia hosourensis Yokoyama 1904

†Geratrigonia kurumensis Kobayashi 1954

G. †Heterotrigonia Cox 1952

†Heterotrigonia diversicostata Whiteaves 1876

†Heterotrigonia sawatai Yehara 1900

G. †Ibotrigonia

G. †Korobkovitrigonia

G. †Kyushutrigonia Tamura and Nishimura 1994

†Kyushutrigonia hachibarensis Tamura and Nishimura 1994

G. †Latitrigonia Kobayashi 1957

G. †Linotrigonia van Hoepen 1929

Subg. †Linotrigonia (Oistotrigonia) Cox 1952

†Linotrigonia fittoni Deshayes 1842

†Linotrigonia linifera van Hoepen 1929

†Linotrigonia meyeri Lycett 1875

G. †Liotrigonia Cox 1952

†Liotrigonia lingonensis Dumortier 1869

G. †Luxitrigonia Guo 1985

†Luxitrigonia menggaensis Guo 1985

G. †Lyroschizodus Newell and Boyd 1975

†Lyroschizodus djemelensis Boyd and Newell 1979

†Lyroschizodus oklahomensis Beede 1907

†Lyroschizodus orbicularis Newell and Boyd 1975

†Lyroschizodus praecox Waagen 1881

†Lyroschizodus subelegans Waagen 1881

†Lyroschizodus tobai Hayasaka 1925

G. †Maputrigonia Leanza 1985

G. †Megatrigonia van Hoepen 1929

Subg. †Megatrigonia (Apiotrigonia) Cox 1952

Subg. †Megatrigonia (Iotrigonia) Van Hoepen 1929

†Megatrigonia arsinoe Philippi 1900

†Megatrigonia carrincurensis Leanza 1941

†Megatrigonia conocardiiformis Krauss 1900

†Megatrigonia discors Philippi 1900

†Megatrigonia eximia Philippi 1899

†Megatrigonia obesa van Hoepen 1929

†Megatrigonia picunensis Weaver 1900

†Megatrigonia pusilla Philippi 1899

†Megatrigonia staffi Lange 1900

G. †Mesotrigonia

G. †Microtrigonia

G. †Minetrigonia Kobayashi and Katayama 1938

†Minetrigonia anadyrensis Kiparisova 1966

†Minetrigonia bulunensis Kiparisova 1966

†Minetrigonia hegiensis Saeki 1925

†Minetrigonia multicostata Korner 1937

†Minetrigonia pascoensis Steinmann 1930

†Minetrigonia suttonensis Clapp and Shimer 1911

Subfm. †Minetrigoniinae Kobayashi 1954

G. †Maoritrigonia Fleming 1962

G. †Perugonia Kobayashi and Tamura 1968

G. †Myophorigonia Cox 1952

†Myophorigonia jaworskii Steinmann 1929

†Myophorigonia kobayashii Tamura and McRoberts 1993

†Myophorigonia margaritifera Boehm 1904

†Myophorigonia parcinoda Lycett 1872

†Myophorigonia paucicostata Jaworski 1922

†Myophorigonia salasi de Cserna 1961

G. Neotrigonia Cossmann 1912

Subg. †Neotrigonia (Callitrigonia)

†Neotrigonia acuticostata McCoy 1866

†Neotrigonia bednalli Verco 1907

†Neotrigonia gemma Iredale 1924

†Neotrigonia kaiyomaruae Habe 1976

†Neotrigonia lamarckii Gray 1838

†Neotrigonia margaritacea Lamarck 1804

Neotrigonia pectinata Lamarck 1819

†Neotrigonia strangei Adams 1854

†Neotrigonia uniophora Gray 1847

Subfm. †Neuquenitrigoniinae Leanza 1993

G. †Neuquenitrigonia Leanza and Garate 1987

G. †Nipponitrigonia Cox 1952

†Nipponitrigonia kikuchiana Yokoyama 1891

†Nipponitrigonia naumanni Yehara 1923

G. †Nototrigonia Cox 1952

†Nototrigonia cinctuta Etheridge 1902

Subfm. †Nototrigoniinae Skwarko 1963

Invalid names: Austrotrigoniinae Skwarko 1968 [synonym]

G. †Opisthotrigonia Cox 1952

†Opisthotrigonia retrorsa Kitchin 1903

G. †Pacitrigonia Marwick 1932

†Pacitrigonia destefanii Feruglio 1900

†Pacitrigonia ecplecta Wilckens 1907

†Pacitrigonia hanetiana d'Orbigny 1842

†Pacitrigonia patagonica Feruglio 1937

†Pacitrigonia sobrali Leanza and Casadío 1991

†Pacitrigonia sylvesteri Marwick 1932

G. †Prorotrigonia Cox 1952

†Prorotrigonia seranensis Krumbeck 1923

Subfm. †Psilotrigoniinae Fleming 1987

G. †Psilotrigonia Cox 1952

G. †Quadratotrigonia Dietrich 1933

†Quadratotrigonia nodosa Sowerby 1830

G. †Quoiecchia Crickmay 1930

†Quoiecchia aliciae Crickmay 1930

G. †Rutitrigonia van Hoepen 1929

†Rutitrigonia affinis Sowerby 1818

†Rutitrigonia agrioensis Weaver 1931

†Rutitrigonia bornhardti Müller 1900

†Rutitrigonia coquandiana d'Orbigny 1844

†Rutitrigonia dietrichi Lange 1914

†Rutitrigonia dunscombiensis Lycett 1900

†Rutitrigonia excentrica Parkinson 1811

†Rutitrigonia jacksonensis Packard 1921

†Rutitrigonia janenschi Lange 1914

†Rutitrigonia laeviuscula Lycett 1875

†Rutitrigonia longa Agassiz 1840

†Rutitrigonia mesembria Tenison-Woods 1900

†Rutitrigonia neumayri Yehara 1923

†Rutitrigonia niongalensis Lange 1914

†Rutitrigonia palaeopatagonica Piatnizky 1900

†Rutitrigonia peregrina van Hoepen 1929

†Rutitrigonia pongolensis Rennie 1936

†Rutitrigonia pseudoindica Archangelski 1916

†Rutitrigonia regina Wilckens 1911

†Rutitrigonia schwarzi Müller 1900

†Rutitrigonia semiculta Forbes 1846

G. †Sichuantrigonia Gou 1993

†Sichuantrigonia verrucosa Gou 1993

G. †Sphenotrigonia Rennie 1936

†Sphenotrigonia frommurzei Rennie 1936

Subfm. Trigoniinae Lamarck 1819

G. †Guineana Skwarko 1967

G. †Magharitrigonia Ayoub-Hannaa et al. 2023

G. †Trigonia Bruguière 1789

G. †Turbitrigonia

Invalid names: Lyrodontidae Bronn 1862 [synonym], Pleurotrigoniinae van Hoepen 1929 [empty]

Superfm. †Trigonioidoidea Cox 1952

Fm. †Jilinoconchidae Ma 1989

G. †Jilinoconcha Ma 1989

†Jilinoconcha songhuaensis Gu and Yu 1976

Fm. †Nakamuranaiadidae Guo 1981

G. †Cyotrigonioides Guo 1981

†Cyotrigonioides puerensis Guo 1981

G. †Enotrigonioides Guo 1987

G. †Nakamuranaia Suzuki 1943

Fm. †Nippononaiidae Chen 1987

G. †Sinonaia Guo 1981

†Sinonaia jingdongensis Guo 1981

Invalid names: Nippononaiinae Chen 1987 [empty], Sinonaiinae Chen 1987 [empty]

Fm. Pseudohyriidae Kobajashi 1968

G. †Gobiola Martinson 1975

Subg. †Gobiola (Matsumotoina) Guo 1982

G. †Pseudohyria MacNeil 1936

Subg. †Pseudohyria (Liotrigonioides) Guo 1986

G. †Weichangella Yu and Yao 1980

†Weichangella caelata Yu and Yao 1980

Fm. †Sainschandiidae Kolesnikov 1977

G. †Sainschandia

Fm. †Trigonioididae Cox 1952

G. †Americunio Guo 1986

†Americunio asinaria Reeside 1957

G. †Eotrigonioides Ma 1989

†Eotrigonioides antiqua Gu and Ma 1976

G. †Hoffetrigonia Suzuki 1940

G. †Linotrigonioides Guo 1987

†Linotrigonioides cancellatus Guo 1987

Subfm. †Martinsonellinae Hong 1965

G. †Martinsonella Hong 1965

G. †Multiplicanaia Yu and Zhang 1984

†Multiplicanaia tujingziensis Yu and Zhang 1984

G. †Nippononaia Suzuki 1941

Subg. †Nippononaia (Arctonaia) Yu 1987

Subg. †Nippononaia (Eomartinsonella) Yu 1987

Subg. †Nippononaia (Eonippononaia) Guo 1981

†Nippononaia yanjiensis Gu 1976

Subfm. †Peregrinoconchinae Gu 1976

G. †Peregrinoconcha Chen and Lan 1976

G. †Pseudohyrioides Ma 1984

G. †Songhuanaia Gu 1976

†Songhuanaia songhuaensis Gu 1976

G. †Trigonioides Kobayashi and Suzuki 1936

Subg. †Trigonioides (Didymotrigonioides) Gu 1976

Subg. †Trigonioides (Diversitrigonioides) Gu 1976

Subg. †Trigonioides (Wakinoa) Yang 1976

Subg. †Trigonioides (Xizangotrigonioides) Guo 1986

G. †Yeniella Modell 1964

Invalid names: Danlengiconchinae Sha 1993 [empty], Trigonioidinae Cox 1952 [empty]

Invalid names: Americunioninae Guo 1986 [empty], Plicatounionidae Chen 1987 [empty]

Superfm. †Trigonodoidea Modell 1942

Fm. †Desertellidae Dechauseaux 1946

G. †Desertella Haug 1905

Fm. †Trigonodidae Modell 1942

G. †Janaija Truschelev 1984

†Janaija magnoplicata Kurushin 1987

†Janaija nikolaevi Kurushin 1987

†Janaija praelonga Kiparisova 1937

†Janaija visibilis Kurushin 1987

G. †Trigonodus Alberti 1864

†Trigonodus abdominalis Jelen 1989

†Trigonodus bittneri Waagen 1907

†Trigonodus brevidens Waagen 1907

†Trigonodus carniolicus Bittner 1907

†Trigonodus costatus Wöhrmann 1892

†Trigonodus dieneri Waagen 1907

†Trigonodus extraordinarius Jelen 1989

†Trigonodus intermedius Waagen 1907

†Trigonodus marmolatae Salomon 1895

†Trigonodus minor Newberry and Worthen 1866

†Trigonodus orientalis Bittner 1899

†Trigonodus postrablensis Frech 1912

†Trigonodus praeco Philippi 1898

†Trigonodus problematicus Klipstein 1843

†Trigonodus productus Whiteaves 1889

†Trigonodus rablensis Gredler 1862

†Trigonodus ramovsi Jelen 1989

†Trigonodus sandbergeri von Alberti 1864

†Trigonodus serianus Parona 1889

†Trigonodus sichuanensis Gu 1976

†Trigonodus subrhombus Guo 1985

†Trigonodus xiabolangensis Yin and Grant-Mackie 2005

†Trigonodus yunnanensis Guo 1985

G. †Virgotrigonia

G. †Zaletrigonia

G. †Zulutrigonia

Invalid names: Beichuanioidea Liu and Gu 1988 [empty], Lyrodesmatacea Ulrich 1894 [empty], Megatrigonioidea van Hoepen 1929 [empty], Myophorellina Cooper 1991 [empty]

Or. Unionida Stoliczka 1871

Superfm. †Archanodontacea Weir 1969

Fm. †Archanodontidae Weir 1969

G. †Archanodon Howse 1878

G. †Dianolimnia Guo 1985

†Dianolimnia lacustris Guo 1985

G. †Neamnigenia Khalfin 1950

†Neamnigenia buhaheensis Lu 1986

Subor. Hyriidina Hoeh 2009

Superfm. Hyrioidea Swainson 1840

Fm. Hyriidae Swainson 1840

G. Callonaia Simpson 1900

G. Castalia Lamarck 1819

Subfm. Hyriinae Swainson 1840

Invalid names: Prisodontinae Modell 1942 [synonym]

Invalid names: Propehyridellidae Iredale 1934 [synonym], Velesunioninae Iredale 1934 [empty]

G. †Protelliptio Russell 1934

Subor. †Silesunionidina Skawina and Dzik 2011

Invalid names: Silesunionoidea Skawina and Dzik 2011 [empty]

Subor. †Silesunionina Skawina and Dzik 2011

Fm. †Silesunionidae Skawina and Dzik 2011

G. †Silesunio Skawina and Dzik 2011

†Silesunio parvus Skawina and Dzik 2011

Invalid names: Unionellidae Skawina and Dzik 2011 [empty]

G. †Tihkia Sahni and Tewari 1958

†Tihkia silesiaca Skawina and Dzik 2011

Subor. Unionidina Gray 1854

Superfm. Mullerioidea Deshayes 1832

Fm. Etheriidae Deshayes 1830

G. Etheria Lamarck 1807

Fm. Iridinidae Swainson 1840

Subfm. Aspathariinae Modell 1942

Invalid names: Spathopsinae Modell 1942 [synonym]

G. Chambardia Servain 1890

Subfm. Iridininae Swainson 1840

Invalid names: Spathinae Bronn 1862 [synonym]

Invalid names: Pleiodontidae Rochebrune 1904 [synonym]

Fm. Mulleriidae Deshayes 1832

Subfm. Monocondylaeinae Modell 1942

G. Mulleria Férussac 1823

Subfm. Mycetopodinae Gray 1840

Invalid names: Acostaeidae Morrison 1973 [synonym]

Invalid names: Leilinae Morretes 1949 [empty], Mulleriinae Deshayes 1832 [empty], Pseudomulleriidae Starobogatov 1970 [synonym]

Superfm. Unionoidea Fleming 1828

Fm. †Actinodontophoridae Newell 1969

G. †Actinodontophora Ichikawa 1951

G. †Linshuiella Ma 1999

G. †Pseudoactinodontophora Murata 1971

G. †Zhongbanaia Ma 1999

Fm. Margaritiferidae Haas 1940

Subfm. Cumberlandiinae Heard and Guckert 1970

G. †Dianoconcha Guo 1988

G. †Margaritifera Schumacher 1815

G. †Mengyinaia Chen 1984

G. †Pseudomargaritifera Ma 1996

G. †Solenoides Ma 1996

Invalid names: Margaritanidae Ortmann 1910 [synonym], Promargaritiferidae Woodward 1994 [synonym]

Fm. †Mutelidae Swainson 1840

G. Leila Gray 1840

G. Mutela Scopoli 1777

Fm. †Pachycardiidae Cox 1961

G. †Cardinioides Kobayashi and Ichikawa 1952

G. †Guangdongella Li and Li 1980

G. †Pachycardia Hauer 1857

G. †Weixiella Guo and Chen 1985

G. †Weiyuanella Xu 1984

G. †Yunnanophorus Chen 1976

G. †Zhifangia Liu 1980

Fm. †Sancticarolitidae Simone and Mezzalira 1997

G. †Sancticarolis Mezzalira 1974

Fm. Unionidae Rafinesque 1820 [freshwater mussel]

G. †Acuneopsis Liu and Zhu 1978

Subfm. †Alasmidontinae Frierson 1927

Subfm. Ambleminae Rafinesque 1820

Invalid names: Cyprogeniinae Starobogatov 1970 [synonym], Friersoniinae Starobogatov 1970 [synonym], Medionidinae Starobogatov 1970 [synonym], Megalonaiadinae Heard and Guckert 1970 [synonym], Popenaiadinae Heard and Guckert 1970 [synonym], Propterinae Hannibal 1912 [synonym], Ptychobranchinae Starobogatov 1970 [synonym]

G. †Anodonta

G. Coelatura Conrad 1853

Subfm. Coelaturinae Modell 1942

Invalid names: Brazzaeainae Leloup 1950 [synonym], Dentaspathariinae Modell 1964 [synonym], Mweruellinae Pain and Woodward 1968 [synonym], Prisodontopsinae Pain and Woodward 1968 [synonym], Pseudospathinae Leloup 1950 [synonym]

G. †Comptio Liu and Luo 1978

G. Cuneopsis Simpson 1900

G. †Danlengiconcha Liu 1978

G. Elongaria Haas 1913

G. †Eocuneopsis Guo 1985

G. †Eolamprotula Gu 1962

Subfm. Gonideinae Ortmann 1916

Invalid names: Hyriopsinae Modell 1942 [synonym], Lamprotulinae Modell 1942 [synonym], Limnoscaphinae Lindholm 1932 [synonym], Pseudodontinae Frierson 1927 [synonym], Psilunioninae Starobogatov 1970 [synonym]

G. †Jishuiconcha Ding et al. 1982

G. Lamprotula Simpson 1900

G. †Liopotomida Ma 1999

G. †Liovetulonaia Ma 1999

G. †Luochengella Liu and Zhu 1978

Subfm. Modellnaiinae Brandt 1974

G. †Ningxiaconcha Ma 1991

G. †Paranodonta Kobayashi and Suzuki 1936

Subfm. Parreysiinae Henderson 1935

Invalid names: Arcidopsinae Starobogatov 1970 [synonym], Hemisolasminae Starobogatov 1970 [synonym], Lamellidentinae Modell 1942 [synonym]

G. †Periodunio Guo 1988

G. †Plicatounio Kobayashi and Suzuki 1936

G. Potomida Swainson 1840

Invalid names: Wenziella Modell 1958 [synonym]

G. Proparreysia Pilsbry 1921

G. †Pseudelliptio Zhu 1976

G. †Psilounio Guo 1985

G. †Qianweiella Liu and Luo 1981

G. †Qiyangia Chen and Xu 1980

G. Quadrula Rafinesque 1820

G. †Radioplicata Huang 1981

Subfm. Rectidentinae Modell 1942

Invalid names: Contradentinae Modell 1942 [synonym], Nannonaiinae Modell 1942 [synonym]

G. †Rhabdotophorus Russell 1935

G. †Shifangella Liu and Luo 1981

G. †Shistodesmus Simpson 1900

G. Solenaia Conrad 1869

G. †Tuberonaia Gu and Huang 1976

G. †Undulatula Gu 1976

G. †Unionelloides Gu 1962

Subfm. Unioninae Fleming 1828

Invalid names: Acuticostinae Starobogatov 1967 [synonym], Cafferiinae Modell 1942 [synonym], Heudeaninae Modell 1942 [synonym], Nodulariinae Starobogatov and Zatravkin 1987 [synonym], Strophitinae Starobogatov 1970 [synonym]

G. †Wulongiconcha Liu 1984

G. †Yunnanoconcha Gu and Ma 1976

Invalid names: Qiyangiinae Chen 1983 [empty]

Invalid names: Actinodontophoroidea Newell 1969 [empty], Amblemidae Rafinesque 1820 [empty], Archanodontoidea Modell 1957 [empty], Carydioidea Haffer 1959 [empty], Etherioidea Deshayes 1830 [empty]

Diagnosis

No diagnoses are available

Measurements

No measurements are available

Composition:

aragonitec

Locomotion:

facultatively mobilec

Life habit:

infaunalc

Diet:

suspension feederc

Vision:

blindc

Created:

2004-02-28 11:33:36

Modified:

2010-02-12 03:59:35

Source: c = class

Reference: Aberhan et al. 2004

Age range

Maximum range based only on fossils: base of the Floian to the top of the Holocene or 477.10000 to 0.00000 Ma
Minimum age of oldest fossil (stem group age): 471.3 Ma

Collections (4993 total)

Time interval	Ma	Country or state	Original ID and collection number
Oldest occurrences
Floian	477.1 - 471.3	China (Yunnan)	Baidiostraca aberrans (200939)
Arenig	477.1 - 468.0	Australia (Queensland)	Trigonodus sp. (157069 157073)
Katian	452.8 - 445.2	Sweden (Dalarna)	Myophoria ebbae (124939)
Wenlock	432.9 - 426.7	China (Jiangsu)	Eoschizodus sp. (27751 27752)
Wenlock	432.9 - 426.7	USA (New York)	Eoschizodus sp. (470)
Homerian - Gorstian	430.6 - 425.0	USA (Alaska)	Schizodus sp. A, Schizodus sp. B (153969)
Lochkovian	419.62 - 413.02	Australia (Victoria)	Eoschizodus sp. (7196 8481)
Lochkovian	419.62 - 413.02	China (Guangxi)	Schizodus cuneus (3998) Schizodus cuneus, Schizodus appressus (4002) Schizodus peregrins (4003)
Lochkovian	419.62 - 413.02	USA (Florida)	Eoschizodus sp. (75630)
Early/Lower Devonian	419.62 - 393.47	Australia (Victoria)	Eoschizodus sp. (8345 8351 8359)
Pragian	413.02 - 410.62	China (Guangxi)	Eoschizodus sp. (25814)
Pragian	413.02 - 410.62	Australia (Victoria)	Dolabra unilateralis (75704 75713 75714) Eoschizodus sp. (8498)
Pragian - Emsian	413.02 - 393.47	Turkey (Istanbul)	Hefteria sp., Toechomya sp., Eoschizodus sp. (32470)
Early/Lower Emsian	410.62 - 399.5	Germany	Pholadella peregrina (232221)
Early/Lower Emsian	410.62 - 399.5	China (Guangxi)	Schizodus sp. (3983)
Early/Lower Emsian	410.62 - 399.5	China (Heilongjiang)	Toechomya sp. (25844)
Early/Lower Emsian	410.62 - 399.5	Australia (Victoria)	Schizodus oweni (35555)
Emsian	410.62 - 393.47	Canada (Quebec)	Schizodus sp. (608)
Emsian	410.62 - 393.47	Australia (New South Wales)	Schizodus oweni (35556) Schizodus truemani, Eoschizodus taemasensis (35557 35558)
Emsian	410.62 - 393.47	China (Yunnan)	Trionychodia bella (200823)