Bivalvia | Unionida | Unionoidea | Unionidae | Ambleminae | Lampsilini
6 Recent freshwater species (8 total species)
Rafinesque, 1819. Jour. Phys. Chim. Hist. Nat. 88: 426.
Rafinesque, 1820. Ann. Gén. Sci. Phys. 5 (13): 302 [as ‘Obliquaria (Plagiola)’].
Rafinesque, 1864. [in] Binney & Tryon, reprint: 29, 46.
(intro'd as sub-gen. of Unio Retzius, 1788)
Type species: Obliquaria (Plagiola) interrupta Rafinesque, 1820 (sub. desig. by Herrmannsen, 1847: 279) = Ptychobranchus fasciolaris
Simpson, 1900. Proc. Acad. Nat. Sci. 52: 79.
Simpson, 1900. Proc. U.S. Nat. Mus. 22: 612.
Simpson, 1914. Descr. Cat. Naiades: 332.
Type species: Unio phaseolus Hildreth, 1828 (orig. desig.) = Ptychobranchus fasciolaris
Frierson, 1927. Check List N. Amer. Naiades: 65.
(intro'd as sub-gen. of Ptychobranchus Simpson, 1900)
Type species: Unio subtentus Say, 1825 (orig. desig.) = Ptychobranchus subtentus
The Taxonomic History lists the ways authors have classified the species currently assigned to Ptychobranchus, since 1900.
Lampsilis (sec. Eurynia) — Simpson (1900)
Medionidus — Simpson (1900)
Ptychobranchus — Simpson (1900), Simpson (1900), Ortmann (1909), Ortmann (1909), Ortmann (1909), ... Bieler (2021), FMCS (2021), Hata et al. (2022), Hopper et al. (2023), FMCS (2025)
Pleurobema (s.s.) — Simpson (1900), Simpson (1914), Frierson (1927)
Unio (s.s.) — Call (1900)
Lampsilis (Eurynia) — Simpson (1914)
Pleurobema — Simpson (1914), Haas (1969)
Unio — de Gregorio (1914), Henderson (1935)
Truncilla — Vanatta (1915), Ortmann (1918)
Ellipsaria — Utterback (1916), Ortmann (1918)
Dysnomia (Truncillopsis) — Ortmann & Walker (1922)
Ptychobranchus (s.s.) — Frierson (1927), Haas (1969), Haas (1969)
Ptychobranchus (Subtentus) — Frierson (1927), Haas (1969), Haas (1969)
Lampsilis (Ligumia) — Frierson (1927)
Lampsilis — Clench & Turner (1956), Athearn (1964), R.I. Johnson (1967)
Plagiola — Morrison (1969), R.I. Johnson (1980)
Obliquaria — Burch (1975)
Plagiola (s.s.) — R.I. Johnson (1978)