Trigonia conferticostata (FOSSIL) Cragin, 1905 †
Geratrigonia convexa (FOSSIL) (Kobayashi, 1954 †)
Nipponitrigonia convexa (FOSSIL) Kobayashi, 1957 †
Trigonia coqueiroensis (FOSSIL) C.J. Maury, 1936 †
Trigonia corderoi (FOSSIL) A. Lambert, 1944 †
Trigonia costata (FOSSIL) Parkinson, 1811 †
Trigonia costata lata (FOSSIL) J. Lycett †
Kupenga coxi (FOSSIL) (Fleming, 1985) †
Trigonia cragini (FOSSIL) Stoyanow, 1949 †
Trigonia crebraecostata (FOSSIL) Pugaczewska, 1976 †
Trigonia crenulata (FOSSIL) J.B.P.A. Lamarck, 1819 †
Trigonia crenulifera (FOSSIL) Lycett †
Trigonia culleni (FOSSIL) J. Lycett, 1877 †
Opisthotrigonia curta (FOSSIL) (Aitken, 1961 †)
Opisthotrigonia curvata (FOSSIL) Aitken, 1961 †
Climacotrigonia dailyi (FOSSIL) Cox, 1964 †
Trigonia densestriata (FOSSIL) Behrendsen, 1892 †
Trigonia denticulata (FOSSIL) A.E.R. Agassiz, 1840 †
Trigonia dhosaensis (FOSSIL) Kitchin, 1903 †
Coxitrigonia distincta (FOSSIL) (Kitchin, 1903) †
Trigonia ehningensis (FOSSIL) (Rollier, 1912 †)
Trigonia elongata (FOSSIL) J. de C. Sowerby, 1823 †
Trigonia elongata angustata (FOSSIL) J. Lycett †
Trigonia elongata gracilis (FOSSIL) Kellaway & Wilson †
Guineana emmerichii (FOSSIL) (H. Winkler, 1859 †)
Eotrigonia eocenica (FOSSIL) T.A. Darragh, 1986 †
Trigonia eptingensis (FOSSIL) Schwarz, 1973 †
Trigonia erbeni (FOSSIL) Alencaster de Cserna,1963 †
Trigonia extentum (FOSSIL) Repman, 1963 †
Trigonia fluehmanni (FOSSIL) R.A. Philippi, 1899 †
Trigonia fortinensis (FOSSIL) A. Lambert, 1944 †
Trigonia gallica (FOSSIL) (Rollier, 1912 †)
Neotrigonia gemma T. Iredale, 1924
Trigonia glosensis (FOSSIL) Bigot, 1893 †
Jaworskiella gryphitica (FOSSIL) (Möricke, 1894 †)