Pseudocrioceras abichii (FOSSIL) (Batsevich, 1873 †)
Kutatissites abiehanus (FOSSIL) (A.V.M.D. D'Orbigny,1851 †)
Ammonitoceras ackermanni (FOSSIL) Krenkel, 1910 †
Tropaeum acutecostatum (FOSSIL) Renngarten, 1951 †
Luppovia adjiderensis (FOSSIL) T.N. Bogdanova, Kakabadze& Mikhailova, 1978 †
Pedioceras aequatorialis (FOSSIL) (von Buch, 1839 †)
Tonohamites aequicingulatus (FOSSIL) (A. von Koenen, 1902 †)
Helicancylus aequicostatus (FOSSIL) (W.M. Gabb, 1864 †)
Ancyloceras ahausense (FOSSIL) Simionescu, 1900 †
Audouliceras ajax (FOSSIL) (F.M. Anderson, 1938 †)
Hamiticeras aliense (FOSSIL) Lobjanidze, 1972 †
Acanthoptychoceras alpinum (FOSSIL) A.V.M.D. D'Orbigny,1850 †
Proaustraliceras altum (FOSSIL) (Glazunova, 1973 †)
Colchidites amplexus (FOSSIL) Renngarten, 1951 †
Paracrioceras andinum (FOSSIL) (Gerth, 1925 †)
Acrioceras anglesense (FOSSIL) Thomel, 1965 †
Ancyloceras angulosum (FOSSIL) A. von Koenen, 1902 †
Paracrioceras annulatum (FOSSIL) (A. von Koenen, 1902 †)
Toxoceras annulatum (FOSSIL) d'Orbigny in Sarkar,1955 †
Tropaeum antarcticum (FOSSIL) R.O. Wilckens, 1947 †
Antarcticoceras antarcticum (FOSSIL) B.H. Thomson, 1974 †
Pseudocrioceras anthulai (FOSSIL) Eristavi, 1955 †
Colchidites apolinari (FOSSIL) (Royo & R. Gomez, 1945 †)
Pedioceras apollinaria (FOSSIL) Basse, 1948 †
Proaustraliceras apticum (FOSSIL) (Glazunova, 1973 †)
Tropaeum arcticum (FOSSIL) (Stolley, 1911 †)
Australiceras argus (FOSSIL) F.M. Anderson, 1938 †
Paracrioceras asiaticum (FOSSIL) (E. Matsumoto, 1947 †)
Toxoceratoides asperulus (FOSSIL) (A. von Koenen, 1902 †)
Ancyloceras astierianum (FOSSIL) A.V.M.D. D'Orbigny,1850 †
Pedioceras asymmetricum (FOSSIL) Kakabadze & Hoedemaeker,1997 †
Colchidites atsharensis (FOSSIL) Rouchadze, 1933 †
Lithancylus attrox (FOSSIL) (F.M. Anderson, 1938 †)
Audouliceras audouli (FOSSIL) Astier, 1851 †
Auritina aurita (FOSSIL) Egoian, 1989 †