Bivalvia | Unionida | Unionoidea | Unionidae | Ambleminae | Quadrulini | Quadrulina
6 Recent freshwater species (6 total species)
Swainson, 1840. Treat. Malacol.: 267-273, 275-276, 289-290, 378.
(intro'd as sub-gen. of Unio Retzius, 1788; renamed Thelyderma Agassiz, 1846)
Type species: Obliquaria (Quadrula) metanevra Rafinesque, 1820 (sub. desig. by Gray, 1847: 196) = Theliderma metanevra
Agassiz, 1846. Nomencl. Zool. Index Univ.: 368.
(new name for Theliderma Swainson, 1840)
Type species: Obliquaria (Quadrula) metanevra Rafinesque, 1820 = Theliderma metanevra
‘Swainson’ of Authors.
Lea, 1852. Synopsis Fam. Naiades: 22.
Reeve, 1864. Conch. Icon. 16: pl. 7,sp. 25.
Lea, 1870. Synopsis Fam. Naiades: 33.
Paetel, 1875. Fam. Gatt. Moll.: 203.
(error for Theliderma Swainson, 1840)
Type species: Obliquaria (Quadrula) metanevra Rafinesque, 1820 = Theliderma metanevra
Agassiz, 1852. Arch. Naturg. 18(1): 48.
Type species: Unio cylindricus Say, 1817 (orig. desig.) = Theliderma cylindrica
The Taxonomic History lists the ways authors have classified the species currently assigned to Theliderma, since 1900.
Quadrula (s.s.) — Simpson (1900), Simpson (1914)
Unio (s.s.) — Call (1900)
Quadrula — Ortmann (1909), Ortmann (1909), Ortmann (1910), Ortmann (1910), Ortmann (1912), ... IUCN (2012), McMurray et al. (2012), Jones (2015), Inoue et al. (2018), Klymus et al. (2020)
Unio — de Gregorio (1914)
Quadrula (Orthonymus) — Frierson (1927), Haas (1930), Haas (1969)
Quadrula (sec. Orthonymus) — F.C. Baker (1928)
Quadrula (sec. Theliderma) — Thiele (1934)
Orthonymus — Haas (1969)
Theliderma — IUCN (1996), IUCN (2000), Graf & Cummings (2007), Cummings & Graf (2010), Campbell & Lydeard (2012), ... Graf & Cummings (2021), FMCS (2021), Neemuchwala et al. (2023), Hopper et al. (2023), FMCS (2025)