Euthria aracanensis G.F. Angas, 1873
Buccinum araitonum R. Tiba, 1981
Amarophos arayaensis (FOSSIL) B.M. Landau & F. Da Silva,2012 †
Probuccinum archibenthale (J.C. Melvill & R. Standen,1907)
Suessionia arenaria (FOSSIL) A.E.M. Cossmann, 1889 †
Tasmeuthria arenicola (FOSSIL) Darragh, 2017 †
Savatieria areolata H. Strebel, 1905
Buccinum argillaceum A.N. Golikov & V.V. Gulbin,1977
Siphonalia ariejansseni (FOSSIL) Schnetler, 2001 †
Engina armillata L.A. Reeve, 1848
Suessionia armoricensis (FOSSIL) (Vasseur, 1881 †)
Bayerius arnoldi (V.J. Lus, 1981)
Neptunea arthritica (FOSSIL) (A.C. Bernardi, 1857 †)
Barbitonia arthritica (A. Valenciennes, 1858)
Aulacofusus asagaensis (FOSSIL) J. Makiyama, 1934 †
Celatoconus asheri (FOSSIL) E.J. Petuch, 1988 †
Penion asper (FOSSIL) (J. Marwick, 1928 †)
Siphonalia aspersa J.T. Kuroda& T. Habe in T. Habe, 1961
Pollia assimilis (L.A. Reeve, 1846)
Engina astricta (L.A. Reeve, 1846)
Prosipho astrolabiensis (H. Strebel, 1908)
Manaria astrolabis Fraussen & Stahlschmidt,2016
Eosipho atlanticus K. Fraussen & R. Hadorn,2005
Monostiolum atlanticus A.C. dos Santos Coelho, H.R. Matthews& al., 1970
Cominella attenuata (FOSSIL) (C.A. Fleming, 1943 †)
Aeneator attenuatus A.W.B. Powell, 1927
Habevolutopsius attenuatus (W.H. Dall, 1874)
Retifusus attenuatus (A.N. Golikov& V.V. Gulbin, 1977)
Pareuthria attra F.A. Schilder & M. Schilder,1938
Cyrtochetus augustulus (FOSSIL) Garvie, 2013 †
Colus aurariae K. Fraussen, J. Rosado, C.M.L. Afonso& A. Monteiro, 2009
Monostiolum auratum G.T. Watters & C.J. Finlay,1989
Crassicantharus aureatus K. Fraussen& P. Stahlschmidt, 2015
Neptunea aurigena K. Fraussen & R.A. Terry,2007
Neptunea aurigena apeliota K. Fraussen & Y. Terryn,2007