Antiplanes abarbarea (W.H. Dall, 1919)
Crassispira abdera (W.H. Dall, 1919)
Comitas abnormis (FOSSIL) L. C. King, 1933 †
Crassispira abundans (FOSSIL) T.A. Conrad, 1840 †
Antiplanes abyssalis Y.I. Kantor & A.V. Sysoev,1991
Inquisitor acervatus B.C. Cotton, 1947
Compsodrillia acestra (W.H. Dall, 1889)
Lioglyphostoma acrocarinatum (W.H. Dall, 1927)
Crassispira adana (P. Bartsch, 1950)
Lioglyphostoma adematum W.P. Woodring, 1928
Inquisitor adenicus A.V. Sysoev, 1996
Carinodrillia adonis H.A. Pilsbry & H.N. Lowe,1932
Carinoturris adrastia (W.H. Dall, 1919)
Crassispira aegis (FOSSIL) W.P. Woodring, 1928 †
Knefastia aenigmatica (FOSSIL) B.M. Landau, F. Da Silva& S.M. Heitz, 2016 †
Comitas aequatorialis (K.H.J. Thiele, 1925)
Comitas aequatorialis palawanica A.W.B. Powell, 1969
Inquisitor aesopus (M.M. Schepman, 1913)
Crassispira affinis (L.A. Reeve, 1846)
Miraclathurella aguadillana (W.H. Dall & W. Stimpson,1901)
Lioglyphostoma aguadillanum (W.H. Dall & C.T. Simpson,1901)
Inquisitor alabaster (L.A. Reeve, 1843)
Comitas albicincta (A. Adams & L.A. Reeve,1850)
Pilsbryspira albiguttata (H.A. Pilsbry, 1904)
Pilsbryspira albinodata (L.A. Reeve, 1846)
Carinodrillia alboangulata (E.A. Smith, 1882)
Pilsbryspira albocincta (C.B. Adams, 1845)
Compsodrillia albonodosa (P.P. Carpenter, 1857)
Compsodrillia alcestis (W.H. Dall, 1919)
Hindsiclava alesidota (W.H. Dall, 1889)
Comitas allani (FOSSIL) Powell, 1942 †
Knefastia altenai O. Macsotay & B. Campos,2001
Pilsbryspira amathea (W.H. Dall, 1919)
Miraclathurella amica (FOSSIL) (H.A. Pilsbry & Johnson,1922 †)
Antiplanes amphitrite W.H. Dall, 1919