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Margaritiferidae

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Central America

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Data last updated
Mon 1 Dec 2025

Bivalvia | Unionoida | Unionoidea | Unionidae | Ambleminae | Quadrulini | Quadrulina

genus Quadrula Rafinesque, 1820: synonymy

5 Recent freshwater species (9 total species)

Synonymy

Quadrula Rafinesque, 1820

Rafinesque, 1820. Ann. Gén. Sci. Phys. 5 (13): 305.
Rafinesque, 1864. [in] Binney & Tryon, reprint: 49.
(intro'd as sub-gen. of Obliquaria Rafinesque, 1820)
Type species: Obliquaria (Quadrula) quadrula Rafinesque, 1820 (sub. desig. by Herrmannsen, 1848: 384) = Quadrula quadrula

Tritogonia Agassiz, 1852

Agassiz, 1852. Arch. Naturg. 18(1): 48.
Type species: Obliquaria (Ellipsaria) verrucosa Rafinesque, 1820 (orig. desig.) = Quadrula verrucosa

Tritogenia Agassiz, 1852

‘Agassiz’ of Authors.
Agassiz, 1852. Arch. Naturg. 18(1): 52.
Mörch, 1853. Cat. Conch. Yoldi 2: 44.
Adams & Adams, 1857. Gen. Rec. Moll. 2(31-32): 496.
Paetel, 1890. Cat. Conch.-Samml. 3: 143.
(error for Tritogonia Agassiz, 1852)
Type species: Obliquaria (Ellipsaria) verrucosa Rafinesque, 1820 = Quadrula verrucosa

Amphinaias Fischer & Crosse, 1894

Fischer & Crosse, 1894. Miss. Sci. Mexique, Rech. Zool. 2(15): 556.
(intro'd as sub-gen. of Unio Retzius, 1788)
Type species: Unio couchianus Lea, 1860 (orig. desig.) = Quadrula couchiana

Quaduila Preston, 1916

Preston, 1916. Zool. Rec. 51: 66.
(error for Quadrula Rafinesque, 1820)
Type species: Obliquaria (Quadrula) quadrula Rafinesque, 1820 = Quadrula quadrula

Quodrula Ortmann, 1910

Ortmann, 1910. Nautilus 23(11): 140.
(error for Quadrula Rafinesque, 1820)
Type species: Obliquaria (Quadrula) quadrula Rafinesque, 1820 = Quadrula quadrula

Tritigonia Morrison, 1955

Morrison, 1955. Ann. Rept. AMU 1955(21): 16.
(error for Tritogonia Agassiz, 1852)
Type species: Obliquaria (Ellipsaria) verrucosa Rafinesque, 1820 = Quadrula verrucosa

Taxonomic History (since 1900)

The Taxonomic History lists the ways authors have classified the species currently assigned to Quadrula, since 1900.

Tritogonia — Simpson (1900), Simpson (1900), Ortmann (1909), Simpson (1914), Vanatta (1915), ... Graf & Cummings (2021), Porto-Hannes et al. (2021), FMCS (2021), Hopper et al. (2023), Hauck et al. (2023)
Quadrula (sec. Theliderma) — Simpson (1900), Simpson (1914)
Unio (Pleurobema) — Martens (1900)
Unio (s.s.) — Call (1900)
Quadrula — Ortmann (1909), Ortmann (1909), Ortmann (1910), Ortmann (1910), Ortmann (1912), ... Freeman et al. (2025), Chen et al. (2025), FMCS (2025), Cummings et al. (2025), Hou et al. (2025)
Unio — de Gregorio (1914), Henderson (1935), Yen (1951)
Hyriopsis — Haas (1924)
Quadrula (s.s.) — Frierson (1927), F.C. Baker (1928), Haas (1930), Haas (1969), Haas (1969)
Quadrula (Tritogonia) — Frierson (1927)
Quadrula (Bullata) — Frierson (1927)
Quadrula (Cyclonaias) — Haas (1930)
Quadrula (sec. Amphinaias) — Thiele (1934)
Orthonymus — Modell (1957)
Quadrula (Pustulosa) — Haas (1969)
Quadrula (Amphinaias) — Haas (1969)
Obliquaria — Burch (1975)
Amphinaias — IUCN (1996), Graf & Cummings (2007), Cummings & Graf (2010)
Q. — Sheng et al. (2014)

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