Ehlersina abditinoda (FOSSIL) E.G. Linsley, 1968 †
Ferganispira acteonina (FOSSIL) Batten, 1995 †
Spiroscala acuminata (FOSSIL) (A. Thomas, 1940 †)
Cataschisma acuta (FOSSIL) Pitcher 1939 †
Cataschisma acute (FOSSIL) Pitcher †
Latitaenia aequicrescens (FOSSIL) (E.F.R.K. Koken, 1897 †)
Spiroraphe aequilatera (FOSSIL) (Wahlenberg, 1821 †)
Mourlonia aifamensis (FOSSIL) Dickins & Skwarko, 1981 †
Apachella alamillano (FOSSIL) (Girty, 1909 †)
Euzone alauna (FOSSIL) E.F.R.K. Koken, 1896 †
Umbotropis albicans (FOSSIL) J. Perner, 1903 †
Peruvispira allandalensis (FOSSIL) E.M. Fletcher, 1958 †
Arizonella allecta (FOSSIL) Stoyanow, 1948 †
Kirchneriella altaica (FOSSIL) (Murchison & al., 1845 †)
Peruvispira alticonica (FOSSIL) Wang, 1980 †
Ananias alticonica (FOSSIL) (Wang, 1980 †)
Glabrocingulum alveozonum (FOSSIL) Batten, 1989 †
Promourlonia ambiqua (FOSSIL) Longst, 1924 †
Glabrocingulum amotapense (FOSSIL) (A. Thomas, 1930 †)
Nipponomaria anatolica (FOSSIL) (Enderle, 1901 †)
Woolnoughia angulata (FOSSIL) Dickins, 1963 †
Stenoloron angulifer (FOSSIL) (Lindström, 1884 †)
Glabrocingulum angulosa (FOSSIL) Rollins, 1975 †
Mourlonia antrina (FOSSIL) (von Schlotheim, 1816 †)
Stenoloron aperiens (FOSSIL) J. Perner, 1907 †
Glyptotomaria apiarium (FOSSIL) Knight, 1945 †
Mourlonia apicalis (FOSSIL) (J.W. Hall, 1876 †)
Ananias appeli (FOSSIL) Batten, 1989 †
Pleurorima aptychia (FOSSIL) Barrande in J. Perner,1907 †
Euryzone arata (FOSSIL) (J.W. Hall, 1862 †)
Eoangyomphalus arctica (FOSSIL) Blodgett & Johnson,1992 †
Stenoloron areyi (FOSSIL) (A.H. Clarke & Ruedemann,1903 †)
Austroneilsonia argentina (FOSSIL) Sabattini, 1975 †
Stenozone argentinus (FOSSIL) (Reed, 1927 †)
Pernotrochus arizonensis (FOSSIL) Chronic, 1952 †