Abra Lamarck, 1818 (redescription)
Abra californica Knudsen, 1970 (redescription)
Abra palmeri Dall, 1915 (redescription)
Abra tepocana Dall, 1915 (redescription)
Acar J. E. Gray, 1857 (redescription)
Acar bailyi Bartsch, 1931 (redescription)
Acar gradata (Broderip & G. B. Sowerby I, 1829) (redescription)
Acar rostae (S. S. Berry, 1954) (source of synonymy)
Acesta H. Adams & A. Adams, 1858 (redescription)
Acesta (Plicacesta) diomedae (Dall, 1908) represented as Acesta diomedae (Dall, 1908) (redescription)
Acesta agassizii (Dall, 1902) (redescription)
Acharax Dall, 1908 (redescription)
Acharax johnsoni (Dall, 1891) (redescription)
Acila H. Adams & A. Adams, 1858 (redescription)
Acila (Truncacila) Schenck, 1931 represented as Acila H. Adams & A. Adams, 1858 (redescription)
Acila (Truncacila) Schenck, 1931 represented as Acila H. Adams & A. Adams, 1858 (additional source)
Acila castrensis (Hinds, 1843) (redescription)
Acrosterigma Dall, 1900 (redescription)
Acrosterigma pristipleura (Dall, 1901) (redescription)
Adontorhina S. S. Berry, 1947 (redescription)
Adontorhina cyclia S. S. Berry, 1947 (redescription)
Adontorhina zelayai Valentich-Scott & Coan, 2012 (original description)
Adrana H. Adams & A. Adams, 1858 (redescription)
Adrana crenifera (G. B. Sowerby I, 1833) (redescription)
Adrana penascoensis (H. N. Lowe, 1935) (redescription)
Adrana sowerbyana (A. d'Orbigny, 1845) (redescription)
Adula H. Adams & A. Adams, 1857 (redescription)
Adula diegensis (Dall, 1911) (redescription)
Adula soleniformis (A. d'Orbigny, 1842) (redescription)
Aequipecten P. Fischer, 1886 (redescription)
Aequipecten glyptus (A. E. Verrill, 1882) (redescription)
Albimanus Pilsbry & Olsson, 1935 (redescription)
Albimanus pentadactylus (Pilsbry & Olsson, 1935) (redescription)
Aligena H. C. Lea, 1843 (redescription)
Aligena muris (Rosewater, 1984) (new combination reference)
Aligena peruviana (Olsson, 1961) accepted as Isorobitella peruviana (Olsson, 1961) (redescription)
Aligena sechura (Olsson, 1961) (basis of record)
Ameghinomya Ihering, 1907 (additional source)
Amerycina Chavan, 1969 (redescription)
Amerycina colpoica (Dall, 1913) (redescription)
Amerycina cultrata Keen, 1971 (redescription)
Amerycina huberi Valentich-Scott, 2012 (original description)
Amiantis P. P. Carpenter, 1864 (redescription)
Amiantis callosa (Conrad, 1837) (redescription)
Amygdalum Megerle von Mühlfeld, 1811 (redescription)
Amygdalum americanum Soot-Ryen, 1955 (redescription)
Amygdalum pallidulum (Dall, 1916) (redescription)
Anadara J. E. Gray, 1847 (redescription)
Anadara adamsi Olsson, 1961 (redescription)
Anadara aequatorialis (A. d'Orbigny, 1846) (redescription)
Anadara biangulata (G. B. Sowerby I, 1833) (redescription)
Anadara bifrons (P. P. Carpenter, 1857) (redescription)
Anadara cepoides (Reeve, 1844) (redescription)
Anadara concinna (G. B. Sowerby I, 1833) (redescription)
Anadara emarginata (G. B. Sowerby I, 1833) (redescription)
Anadara esmeralda (Pilsbry & Olsson, 1941) (redescription)
Anadara formosa (G. B. Sowerby I, 1833) (redescription)
Anadara grandis (Broderip & G. B. Sowerby I, 1829) accepted as Larkinia grandis (Broderip & G. B. Sowerby I, 1829) (redescription)
Anadara hyphalopilema G. B. Campbell, 1962 (redescription)
Anadara labiosa (G. B. Sowerby I, 1833) (redescription)
Anadara mazatlanica (Hertlein & A. M. Strong, 1943) (redescription)
Anadara multicostata (G. B. Sowerby I, 1833) accepted as Larkinia multicostata (G. B. Sowerby I, 1833) (redescription)
Anadara nux (G. B. Sowerby I, 1833) (redescription)
Anadara obesa (G. B. Sowerby I, 1833) (redescription)
Anadara perlabiata (U. S. Grant & Gale, 1931) (redescription)
Anadara reinharti (H. N. Lowe, 1935) (redescription)
Anadara similis (C. B. Adams, 1852) (redescription)
Anadara tuberculosa (G. B. Sowerby I, 1833) (redescription)
Anadarinae Reinhart, 1935 represented as Arcidae Lamarck, 1809 (redescription)
Anatina Schumacher, 1817 (additional source)
Anatina cyprinus (W. Wood, 1828) (redescription)
Anodontia edentuloides (A. E. Verrill, 1870) (redescription)
Anomia Linnaeus, 1758 (redescription)
Anomia peruviana A. d'Orbigny, 1846 (redescription)
Anomiidae Rafinesque, 1815 (redescription)
Apiocardia Olsson, 1961 (additional source)
Apiocardia obovalis (G. B. Sowerby I, 1833) (redescription)
Arca Linnaeus, 1758 (additional source)
Arca pacifica (G. B. Sowerby I, 1833) (redescription)
Archivesica Dall, 1908 (redescription)
Archivesica gigas (Dall, 1896) (redescription)
Arcidae Lamarck, 1809 (redescription)
Arcinae Lamarck, 1809 represented as Arcidae Lamarck, 1809 (redescription)
Arcinella Schumacher, 1817 (additional source)
Arcinella californica (Dall, 1903) (redescription)
Arcopsis Koenen, 1885 (redescription)
Arcopsis solida (G. B. Sowerby I, 1833) (redescription)
Ardeamya Olsson, 1961 (source of synonymy)
Argopecten Monterosato, 1889 (redescription)
Argopecten purpuratus (Lamarck, 1819) (redescription)
Argopecten ventricosus (G. B. Sowerby II, 1842) (redescription)
Asthenothaerus P. P. Carpenter, 1864 (redescription)
Asthenothaerus diegensis (Dall, 1915) (redescription)
Asthenothaerus villosior P. P. Carpenter, 1864 (redescription)
Atrina Gray, 1842 (redescription)
Atrina maura (G. B. Sowerby I, 1835) (redescription)
Atrina oldroydii Dall, 1901 (redescription)
Atrina texta Hertlein, G. D. Hanna & A. M. Strong, 1943 (redescription)
Atrina tuberculosa (G. B. Sowerby I, 1835) (redescription)
Axinactis Mörch, 1861 (basis of record)