Retimohnia clarki (W.H. Dall, 1907) Aleutian Islands
Bathybuccinum clarki Y.I. Kantor& M.G. Harasewych, 1998
Pisania clathrata P. Dautzenberg& H. Fischer, 1906 Morocco, cap Cantin
Meteuthria clathratula (K.H.J. Thiele, 1925)
Austrofusus claviculus (FOSSIL) L. C. King, 1933 †
Cominella clelandi (FOSSIL) R. Tate, 1888 †
Limatofusus clementinus (W.H. Dall, 1919) America
Aeneator cleryanus (FOSSIL) (A.V.M.D. D'Orbigny,1842 †) Chile, Navidad Formation43 mm
Penion clifdenensis (FOSSIL) (Finlay, 1930 †)
Austrofusus cliftonensis (J. Marwick, 1926 ) New Zealand
Buccinum cnismatopleura (W.H. Dall, 1919) Alaska, Point Barrow
Buccinum cnismatum W.H. Dall, 1907 Aleutian Islands, Unalaska Island
Buccinum cnismatum chibanum J.T. Kuroda, 1964 Japan, Chiba69,6 mm
Solenosteira cochlearis (FOSSIL) (R.J.L. Guppy, 1873 †) Colombia, La Chorrera
Austrofusus coerulescens (FOSSIL) (Finlay, 1930 †)
Aulacofusus coerulescens J.T. Kuroda& T. Habe in T. Habe, 1961 Japan, Kochi
Buccinulum colensoi (H.H. Suter, 1908) New Zealand, North Island22 mm
Eocantharus colombiana (FOSSIL) Clark & J.W. Durham,1946 † Colombia, Bolivar
Janiopsis colridusensis (FOSSIL) (J.M. Pacaud & Leroy,2015 †)
Neptunea columbiana A.G. Smith, 1958
Fax cominelloides (FOSSIL) (R. Tate, 1888 †) Australia, Victoria, S. Grampians Bal
Siphonalia commoda A. Adams, 1863 Japan
Neptunea communis (A.T. von Middendorff,1848) Bering Sea
Neptunea communis clarki (F.B. Meek, 1923) Bering Sea66 mm
Cominella compacta (FOSSIL) J. Marwick, 1926 †
Nassicola compacta (FOSSIL) (H.H. Suter, 1917 †) New Zealand
Buccinulum compactum (FOSSIL) (H.H. Suter, 1917 †) New Zealand
Aeneator comptus (H.J. Finlay, 1924) New Zealand, Hauraki Gulf44 mm
Siphonalia concinna A. Adams, 1863 China, Zhejiang61 mm
Caducifer concinnus (L.A. Reeve, 1844) Philippines, Olango Island14 mm
Aeneator conformatus (FOSSIL) (J. Marwick, 1931 †)
Prosipho congenitus E.A. Smith, 1915 Antarctica
Cominella conica (FOSSIL) Bell A. † UK, England, Suffolk
Parvisipho conjunctispira (FOSSIL) A.E.M. Cossmann † France, Normandy
Buccinum conoideum G.O. Sars, 1878 Norway