Cyclocardia orbicularis chamaeformis (FOSSIL) (J. de C. Sowerby,1825 †) Belgium
Cyclocardia orbicularis paucicostata (FOSSIL) (A. Krause, 1885 †) Germany, Rheinland-Pfalz8 mm
Cyclocardia orientalis (FOSSIL) L. Krishtofovich, 1984 † Western Kamchatka
Cyclocardia ornata (FOSSIL) (G.P. Deshayes, 1858 †) France, Paris Basin10 mm
Cyclocardia otatsumei (FOSSIL) S. Uozumi, 1955 † Japan, Hokkaido, Utashinai
Cyclocardia ovata (Riabinina, 1952) Alaska
Cyclocardia ovata (Rjabinina, 1952) Russia, Sakhalin
Cyclocardia ovraensis (FOSSIL) V.N. Sinelnikova, 1991 † Western Kamchatka
Cyclocardia oyamai (FOSSIL) A.I. Kafanov, K. Ogasawara& K. Amano, 1999 † Western Kamchatka
Cyclocardia penzhensis (FOSSIL) A.M. Popov, 1983 † Western Kamchatka
Cyclocardia pilvoensis (FOSSIL) (Khomenko, 1934 †) Russia, Sakhalin
Cyclocardia pliocenica (FOSSIL) A.M. Popov, 1983 † Russia, Sakhalin
Cyclocardia praeruptensis (FOSSIL) (Slodkewitsch, 1938 †) Western Kamchatka
Cyclocardia prevosti (FOSSIL) (G.P. Deshayes, 1858 †) France, Paris Basin17 mm
Cyclocardia propinqua (FOSSIL) (G.P. Deshayes, 1858 †) France, Paris Basin16 mm
Cyclocardia pseutella (FOSSIL) J. Marwick, 1929 † New Zealand, Oamaru
Cyclocardia puella (FOSSIL) (Slodkewitsch, 1938 †) Western Kamchatka
Cyclocardia pusilla (FOSSIL) (G.P. Deshayes, 1858 †) France, Paris Basin
Cyclocardia ripensis A.M. Popov& O.A. Scarlato, 1980 Russia, Okhotsk Sea
Cyclocardia rjabininae (O.A. Scarlato, 1955) USA, Rhode Island
Cyclocardia roundiformis (FOSSIL) (Ilyina, 1963 †) Western Kamchatka
Cyclocardia siogamensis (FOSSIL) S. Nomura, 1957 † Japan, Fukushima, Iwaki
Cyclocardia spurca (Sowerby, 1833) Panama, Coiba Island36 mm
Cyclocardia steinkei (FOSSIL) Clark & J.W. Durham,1946 † Colombia, Sucre
Cyclocardia subrotunda (FOSSIL) (J.L.M. Defrance, 1828 †) France, Paris Basin17 mm
Cyclocardia subtenta (FOSSIL) (T.A. Conrad, 1849 †) Oregon, Coos bay, Astoria formation19 mm
Cyclocardia subtenta quadrata (FOSSIL) (W.H. Dall †) Oregon, Coos bay, Astoria formation27 mm
Cyclocardia terryi (FOSSIL) A.A. Olsson, 1922 † Colombia, La Chorrera
Cyclocardia thouarsii (A.V.M.D. D'Orbigny,1845)
Cyclocardia tjuschevkensis (FOSSIL) (Ilyina, 1963 †) Western Kamchatka
Cyclocardia tokunagai (FOSSIL) (M. Yokoyama, 1924 †) Japan, Saitama, Ogano
Cyclocardia trentensis (FOSSIL) Ward, 1992 † USA, North Carolina, Onslow
Cyclocardia umnaka (G. Willett, 1932) America
Cyclocardia utcholokensis (FOSSIL) (Slodkewitsch, 1938 †) Western Kamchatka
Cyclocardia uvutschensis (FOSSIL) (Ilyina, 1963 †) Western Kamchatka