Cyclocardia kieli (FOSSIL) C. Nielsen, 2013 †
Cyclocardia kirkerensis (FOSSIL) Clark, 1918 †
Cyclocardia kurilensis (FOSSIL) Savizky, 1981 †
Cyclocardia kurilensis (FOSSIL) Savisky, 1981 †
Cyclocardia lutosa (FOSSIL) L.S. Zhidkova& Krishtofovich, 1984 †
Cyclocardia magica (FOSSIL) (Devjatilova, 1981 †)
Cyclocardia magna (FOSSIL) Quilty & al., 2016 †
Cyclocardia marama (FOSSIL) (P.A. Maxwell, 1969 †)
Cyclocardia mesembria (FOSSIL) J.D. Stilwell& Zinsmeister, 1992 †
Cyclocardia moniliata (W.H. Dall, 1903)
Cyclocardia moniligena C.J.S. Hickman, 2015
Cyclocardia montereyana (FOSSIL) R. Arnold, 1908 †
Cyclocardia myogadaniensis (FOSSIL) (Itoigawa †)
Cyclocardia nipponensis M. Huber, 2010
Cyclocardia novangliae (E.S. Morse, 1869)
Cyclocardia occidentalis (FOSSIL) (T.A. Conrad, 1855 †)
Cyclocardia ochotica (FOSSIL) (Slodkewitsch, 1936 †)
Cyclocardia orbica (FOSSIL) M. Yokoyama, 1925 †
Cyclocardia orbicularis (FOSSIL) (E. Forbes, 1846 †)
Cyclocardia orbicularis chamaeformis (FOSSIL) (J. de C. Sowerby,1825 †)
Cyclocardia orbicularis paucicostata (FOSSIL) (A. Krause, 1885 †)
Cyclocardia orientalis (FOSSIL) L. Krishtofovich, 1984 †
Cyclocardia ornata (FOSSIL) (G.P. Deshayes, 1858 †)
Cyclocardia otatsumei (FOSSIL) S. Uozumi, 1955 †
Cyclocardia ovata (Riabinina, 1952)
Cyclocardia ovata (Rjabinina, 1952)
Cyclocardia ovraensis (FOSSIL) V.N. Sinelnikova, 1991 †
Cyclocardia oyamai (FOSSIL) A.I. Kafanov, K. Ogasawara& K. Amano, 1999 †
Cyclocardia penzhensis (FOSSIL) A.M. Popov, 1983 †
Cyclocardia pilvoensis (FOSSIL) (Khomenko, 1934 †)
Cyclocardia pliocenica (FOSSIL) A.M. Popov, 1983 †
Cyclocardia praeruptensis (FOSSIL) (Slodkewitsch, 1938 †)
Cyclocardia prevosti (FOSSIL) (G.P. Deshayes, 1858 †)
Cyclocardia propinqua (FOSSIL) (G.P. Deshayes, 1858 †)
Cyclocardia pseutella (FOSSIL) J. Marwick, 1929 †