Bivalvia | Unionida | Hyrioidea | Hyriidae | Hyriinae | Rhipidodontini | Diplodon
(homonym of Unio (Aximedia) elliptica Rafinesque, 1820; correct name for Diplodon ellypticum Spix in Wagner, 1827; renamed Diplodon (s.s.) wagnerianum Simpson, 1900)
Spix in Wagner, 1827. Test. Fluv. Brasil.: 33.
Spix in Wagner, 1827. Test. Fluv. Brasil.: pl. 26, figs. 1-2 [as Diplodon ellypticum].
Diplodon (s.s.) wagnerianum — Simpson (1900)
Diplodon ellipticus — Ihering (1910), Parodiz (1968), Mansur (1970), Simone (2006), Graf & Cummings (2007), Bogan (2010), Miyahira et al. (2019), Mansur et al. (2020), Graf & Cummings (2021), Nagel (2025)
Diplodon (s.s.) wagnerianus — Simpson (1914), Thiele (1934)
Diplodon (s.s.) ellipticus — Ortmann (1921), Pereira et al. (2014)
Diplodon (s.s.) granosus ellypticus — Haas (1931), Haas (1969)
Diplodon (s.s.) granosus ellipticus — Bonetto (1964)
Diplodon ellipticum — Graf (2000)
Diplodon wagnerianum — Marshall et al. (2014)
(incorrect original spelling of Diplodon ellipticum Spix in Wagner, 1827)
Spix in Wagner, 1827. Test. Fluv. Brasil.: pl. 26, figs. 1-2.
Diplodon (s.s.) wagnerianum — Simpson (1900)
Diplodon (s.s.) wagnerianus — Simpson (1914)
Diplodon (s.s.) ellipticus — Ortmann (1921)
Diplodon (s.s.) granosus ellypticus — Haas (1931), Haas (1969)
Diplodon ellipticus — Parodiz (1968), Mansur (1970), Simone (2006), Miyahira et al. (2019)
Diplodon (s.s.) ellypticum — Haas (1969)
Diplodon ellipticus [sic] — Bogan (2010)
Diplodon granosus ellypticum — IUCN (2011)

Lea, 1856. Proc. Acad. Nat. Sci. 8: 94.
Lea, 1857. Jour. Acad. Nat. Sci. 3 [O. 6]: 305 [25], pl. 28, fig. 20.
LECTOTYPE USNM_84155 (by R.I. Johnson, 1974: 50), Rio Grande, New Grenada.
Diplodon (s.s.) atratus — Simpson (1900)
Diplodon (s.s.) dunkerianus — Simpson (1914), Pereira et al. (2014)
Diplodon rhuacoicus — Haas (1930), Simone (2006)
Diplodon (s.s.) rhuacoicus — Figueiras (1965), Haas (1969)
Diplodon parallelipipedon [sic] aethiops — Parodiz (1968)
Diplodon dunkerianus — Mansur (1970), IUCN (1996)
Diplodon ellipticus — Miyahira et al. (2019), Mansur et al. (2020), Nagel (2025)
‘Pfeiffer teste Charpentier’ Küster, 1856. Conchyl. Cab. 9(2): 145, pl. 42, fig. 5.
Diplodon (s.s.) rhuaconicus — Simpson (1900), Simpson (1914)
Diplodon wheatleyanus — Haas (1930)
Schleschiella burroughiana rhuacoica [sic] — Modell (1950)
Diplodon burroughianus wheatleyanus — Parodiz (1968)
Diplodon (s.s.) wheatleyanus — Haas (1969)
Rhipidodonta burroughiana — Simone (2006)
Diplodon ellipticus — Miyahira et al. (2019)
(reference to Diplodon ellipticum Spix in Wagner, 1827)
‘Spix & Wagner’ of Authors.
Küster, 1861. Conchyl. Cab. 9(2): 238, pl. 80, fig. 2.
‘Spix’ Sowerby, 1868. Conch. Icon. 16: pl. 74, sp. 382.
Diplodon (s.s.) wagnerianum — Simpson (1900)
Diplodon (s.s.) wagnerianus — Simpson (1914)
Diplodon ellipticus — Mansur (1970), Miyahira et al. (2019)
(new name for Diplodon ellipticum Spix in Wagner, 1827)
Simpson, 1900. Proc. U.S. Nat. Mus. 22: 877.
Simpson, 1914. Descr. Cat. Naiades: 1246 [as ‘wagnerianus’].
Diplodon (s.s.) wagnerianum — Simpson (1900)
Diplodon (s.s.) wagnerianus — Simpson (1914), Thiele (1934)
Diplodon (s.s.) ellipticus — Ortmann (1921)
Diplodon (s.s.) granosus ellypticus — Haas (1931), Haas (1969)
Diplodon (s.s.) wagnerianus wagnerianus — Morretes (1949)
Diplodon wagnerianus — Bonetto (1959)
Diplodon ellipticus — Parodiz (1968), Mansur (1970), Simone (2006), Miyahira et al. (2019)
Diplodon wagnerianum — Marshall et al. (2014)

Marshall, 1928. Proc. U.S. Nat. Mus. 74(2762): 1, pl. 4, figs. 1-3.
HOLOTYPE USNM_368260, Arcas, Minas Geraes, Brazil.
Diplodon (s.s.) granosus ellypticus — Haas (1931), Haas (1969)
Diplodon (s.s.) jacksoni — Morretes (1949)
Diplodon ellipticus — Parodiz (1968), Mansur (1970), Simone (2006), Nagel (2025)
(error for Unio rhuaconicus Küster, 1856)
‘Küster’ Modell, 1950. Arch. Moll. 79(4/6): 141.
(error for Diplodon (s.s.) wagnerianum Simpson, 1900)
‘Simpson’ Simone, 2006. Land. Freshw. Moll. Brazil.: 257.
Diplodon ellipticus — Simone (2006)
Diplodon (s.s.) wagnerianum — Simpson (1900)
Diplodon (s.s.) atratus — Simpson (1900)
Diplodon (s.s.) rhuaconicus — Simpson (1900), Simpson (1914)
Diplodon ellipticus — Ihering (1910), Parodiz (1968), Mansur (1970), Simone (2006), Graf & Cummings (2007), Bogan (2010), Miyahira et al. (2019), Mansur et al. (2020), Graf & Cummings (2021), Nagel (2025)
Diplodon (s.s.) wagnerianus — Simpson (1914), Thiele (1934)
Diplodon (s.s.) dunkerianus — Simpson (1914), Pereira et al. (2014)
Diplodon (s.s.) ellipticus — Ortmann (1921), Pereira et al. (2014)
Diplodon rhuacoicus — Haas (1930), Simone (2006)
Diplodon wheatleyanus — Haas (1930)
Diplodon (s.s.) granosus ellypticus — Haas (1931), Haas (1969)
Diplodon (s.s.) wagnerianus wagnerianus — Morretes (1949)
Diplodon (s.s.) jacksoni — Morretes (1949)
Schleschiella burroughiana rhuacoica [sic] — Modell (1950)
Diplodon wagnerianus — Bonetto (1959)
Diplodon (s.s.) granosus ellipticus — Bonetto (1964)
Diplodon (s.s.) rhuacoicus — Figueiras (1965), Haas (1969)
Diplodon parallelipipedon [sic] aethiops — Parodiz (1968)
Diplodon burroughianus wheatleyanus — Parodiz (1968)
Diplodon (s.s.) wheatleyanus — Haas (1969)
Diplodon (s.s.) ellypticum — Haas (1969)
Diplodon dunkerianus — Mansur (1970), IUCN (1996)
Diplodon ellipticum — Graf (2000)
Rhipidodonta burroughiana — Simone (2006)
Diplodon ellipticus [sic] — Bogan (2010)
Diplodon granosus ellypticum — IUCN (2011)
Diplodon wagnerianum — Marshall et al. (2014)