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 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 cultrata Keen, 1958 accepted as Adrana sowerbyana (A. d'Orbigny, 1846) (source of synonymy)
Adrana exoptata (Pilsbry & H. N. Lowe, 1932) accepted as Adrana metcalfei (Hanley, 1860) (redescription)
Adrana penascoensis (H. N. Lowe, 1935) (redescription)
Adrana sowerbyana (A. d'Orbigny, 1846) (redescription)
Adula H. Adams & A. Adams, 1857 (redescription)
Adula diegensis (Dall, 1911) (redescription)
Adula soleniformis (A. d'Orbigny, 1846) (redescription)
Adula soleniformis panamensis Olsson, 1961 accepted as Adula soleniformis (A. d'Orbigny, 1846) (source of synonymy)
Aequipecten P. Fischer, 1886 (redescription)
Aequipecten (Pacipecten) Olsson, 1961 accepted as Leptopecten A. E. Verrill, 1897 (source of synonymy)
Aequipecten glyptus (A. E. Verrill, 1882) (redescription)
Agriodesma Dall, 1909 accepted as Entodesma R. A. Philippi, 1845 (source of synonymy)
Agriopoma aequinoctiale Fischer-Piette, 1969 accepted as Pitar consanguineus (C. B. Adams, 1852) (source of synonymy)
Albimanus Pilsbry & Olsson, 1935 (redescription)
Albimanus pentadactylus (Pilsbry & Olsson, 1935) (redescription)
Aligena H. C. Lea, 1843 (redescription)
Aligena cerritensis Arnold, 1903 † accepted as Isorobitella trigonalis (P. P. Carpenter, 1857) (source of synonymy)
Aligena cokeri Dall, 1909 accepted as Kelliopsis cokeri (Dall, 1909) (redescription)
Aligena muris (Rosewater, 1984) (new combination reference)
Aligena nucea Dall, 1913 accepted as Kelliopsis nucea (Dall, 1913) (redescription)
Aligena peruviana (Olsson, 1961) accepted as Isorobitella peruviana (Olsson, 1961) (redescription)
Aligena sechura (Olsson, 1961) (basis of record)
Aligena trigonalis (P. P. Carpenter, 1857) accepted as Isorobitella trigonalis (P. P. Carpenter, 1857) (redescription)
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)
Amerycina mikkelsenae Valentich-Scott, 2012 accepted as Litigiella mikkelsenae (Valentich-Scott, 2012) (original description)
Amiantis P. P. Carpenter, 1864 (redescription)
Amiantis callosa (Conrad, 1837) (redescription)
Amphichaena gracilis Mörch, 1860 accepted as Donax kindermanni (R. A. Philippi, 1847) (source of synonymy)
Amphidesma croceum A. Gould, 1850 accepted as Semele corrugata (G. B. Sowerby I, 1833) (source of synonymy)
Amphidesma laeta Reeve, 1853 accepted as Semele purpurascens (Gmelin, 1791) (source of synonymy)
Amphidesma nucleola Lamarck, 1818 accepted as Lasaea adansoni (Gmelin, 1791) (source of synonymy)
Amphidesma pulchella Reeve, 1853 accepted as Semele bicolor (C. B. Adams, 1852) (source of synonymy)
Amphidesma rubrolineatum Conrad, 1837 accepted as Semele decisa (Conrad, 1837) (source of synonymy)
Amphidesma simplex A. Adams & Reeve, 1850 accepted as Semele pulchra (G. B. Sowerby I, 1833) (source of synonymy)
Amphidesma striosum C. B. Adams, 1852 accepted as Semele pulchra (G. B. Sowerby I, 1833) (source of synonymy)
Amphidesma variegata Lamarck, 1818 accepted as Semele purpurascens (Gmelin, 1791) (source of synonymy)
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 alta C. B. Adams, 1852 accepted as Periploma lenticulare G. B. Sowerby I, 1834 (source of synonymy)
Anatina cyprinus (W. Wood, 1828) (redescription)
Angulus gouldii P. P. Carpenter, 1864 accepted as Tampaella meropsis (Dall, 1900) (source of synonymy)
Anodontia edentuloides (A. E. Verrill, 1870) (redescription)
Anomalocardia broggi Pilsbry & Olsson, 1943 accepted as Iliochione subrugosa (W. Wood, 1828) (source of synonymy)
Anomalocardia mangeri Hertlein & A. M. Strong, 1948 accepted as Globivenus fordii (L. G. Yates, 1890) (source of synonymy)
Anomalocardia subrugosa Manger, 1934 accepted as Globivenus fordii (L. G. Yates, 1890) (source of synonymy)
Anomia Linnaeus, 1758 (redescription)
Anomia adamas Gray, 1850 accepted as Anomia peruviana A. d'Orbigny, 1846 (source of synonymy)
Anomia alectus Gray, 1850 accepted as Anomia peruviana A. d'Orbigny, 1846 (source of synonymy)
Anomia fidenas Gray, 1850 accepted as Anomia peruviana A. d'Orbigny, 1846 (source of synonymy)

Patagonia for Petricola patagonica A. d'Orbigny, 1846 

 Nomenclature

 for Alvania sculptilis (May, 1920)

Alvania sculptilis (May, 1920) is a junior secondary homonym of Alvania sculptilis (Monterosato, 1877). However, ... [details]

 Taxonomic remark

 for 

In the synonymy of Mytella guyanensis (Lamarck, 1819), Coan & Valentich-Scott (2012, p. 115) list "Modiola bicolor ... [details]