MUSSELpdb
Taxonomy
Species & Genus Richness of
freshwater mussels
by Taxonomy
Species & Genus Richness of
freshwater bivalves
by Family
Geography
Species Richness & Endemism of
freshwater mussels
by Geography
Data last updated
Mon 2 March 2026
Bivalvia | ... | Unionoidea | Unionidae | Ambleminae | Quadrulini | Megalonaias nervosa
nominal species Unio heros Say, 1829
Unio heros Say, 1829 = Megalonaias nervosa
Say, 1829. New Harm. Dissem. 2(19): 291, sp. 1.
Say, 1858. [in] Binney, Compl. Writings T. Say: 165, 225.
Type(s): TYPE LOST XXX_UNKNOWN, Fox River of the Wabash.
Taxonomic Opinions
+ Megalonaias nervosa (Rafinesque, 1820) — Cummings et al., 2025: 450.
+ Megalonaias nervosa (Rafinesque, 1820) — Graf & Cummings, 2021: 20.
+ Megalonaias nervosa (Rafinesque, 1820) — Pfeiffer et al., 2019: 108.
+ Megalonaias nervosa (Rafinesque, 1820) — Pfeiffer et al., 2018: 147.
+ Megalonaias nervosa (Rafinesque, 1820) — Williams et al., 2014: 281.
+ Megalonaias nervosa (Rafinesque, 1820) — Watters et al., 2009: 191.
+ Megalonaias nervosa (Rafinesque, 1820) — Williams et al., 2008: 451.
+ Megalonaias nervosa (Rafinesque, 1820) — Graf & Cummings, 2007: 308.
+ Megalonaias nervosa (Rafinesque, 1820) — Brim Box & Williams, 2000: 62.
+ Megalonaias nervosa (Rafinesque, 1820) — Parmalee & Bogan, 1998: 159.
+ Megalonaias nervosa (Rafinesque, 1820) — Howells et al., 1996: 81.
+ Megalonaias nervosa (Rafinesque, 1820) — Vidrine, 1993: 38.
+ Megalonaias nervosa (Rafinesque, 1820) — Oesch, 1984: 73.
+ Megalonaias gigantea (Barnes, 1823) — R.I. Johnson, 1980: 90.
+ Megalonaias gigantea (Barnes, 1823) — Burch, 1975: 164.
+ Megalonaias gigantea gigantea (Barnes, 1823) — Haas, 1969: 284.
+ Megalonaias gigantea (Barnes, 1823) — Haas, 1969: N439.
+ Megalonaias gigantea (Barnes, 1823) — Murray & Leonard, 1962: 42.
= Amblema (sec. Megalonaias) heros (Say) — Thiele, 1934: 827, [1260].
+ Amblema (Megalonaias) gigantea (Barnes) — Haas, 1930: 328.
+ Megalonaias gigantea (Barnes, 1823) — F.C. Baker, 1928: 69.
+ Amblema (Megalonaias) gigantea (Barnes, 1823) — Frierson, 1927: 62.
= Megalonaias heros Say — Ortmann, 1923: 75.
+ Megalonaias gigantea (Barnes, 1823) — Ortmann & Walker, 1922: 7.
= Megalonaias heros (Say) — Utterback, 1915: 125, text fig. 2, pl. 7, fig. 16, pl. 17, figs. 48a-f.
= Quadrula (sec. Crenodonta) heros (Say, 1829) — Simpson, 1914: 825.
= Crenodonta heros (Say, 1829) — Ortmann, 1912: 248.
= Quadrula heros Say — Ortmann, 1909: 100.
= Quadrula (sec. Crenodonta) heros (Say, 1829) — Simpson, 1900: 770.
+ Unio (s.s.) multiplicatus Lea, 1831 — Call, 1900: 448.
+ Unio multiplicatus Lea, 1830-31 — Call, 1895: 29.
= Unio heros Say — B.H. Wright, 1888: [3].
+ Margaron (Unio) multiplicatus (Lea) — Lea, 1870: 29.
= Unio heros Say, 1829 — Reeve, 1864: pl. 2, sp. 8; pl. 4, sp. 13.
= Unio heros Say — Küster, 1855: 136, pl. 40, figs. 1-2.
= Complanaria heros — Agassiz, 1852: 49.
+ Margaron (Unio) multiplicatus (Lea) — Lea, 1852: 20.
= Unio heros Say — Hanley, 1843: 175, pl. 22, fig. 28.
= Unio heros Say, 1829 — Conrad, 1840: 107, pl. 59.
+ Margarita (Unio) multiplicatus Lea — Lea, 1838: 14.
+ Margarita (Unio) multiplicatus (Lea, 1831) — Lea, 1836: 12.
= Unio heros Say — Ferussac, 1835: 27.
