Bivalvia | Unionida | Hyrioidea | Hyriidae | Hyriinae | Rhipidodontini | Diplodon

Spix in Wagner, 1827. Test. Fluv. Brasil.: 34, pl. 28, figs. 1-2.
Type(s): SYNTYPE SMF_3866, Rio Solimoes, Amazonas Geb. Bras.
Diplodon (s.s.) rhombeus — Simpson (1900), Simpson (1914), Pereira et al. (2014)
Diplodon (Cyclomya) rhombeus — Haas (1931)
Diplodon rhombeus — Parodiz (1968), Mansur et al. (2020), Graf & Cummings (2021)
Diplodon (Rhipidodonta) rhombeus — Haas (1969)
Rhipidodonta rhombea — Simone (2006), Graf & Cummings (2007), Bogan (2010)
Diplodon rhombea — ITIS (2013)

Lea, 1860. Proc. Acad. Nat. Sci. 12: 89.
Lea, 1863. Jour. Acad. Nat. Sci. 5 [O. 10]: 383 [19], pl. 43, fig. 291.
Type(s): HOLOTYPE USNM_85780, Amazon R., Brazil.
Diplodon (Cyclomya s.s.) patelloides — Simpson (1900), Simpson (1914)
Diplodon (Cyclomya) rhombeus — Haas (1931)
Diplodon paranensis — Parodiz (1968), Quintana (1982)
Diplodon (Rhipidodonta) rhombeus — Haas (1969)
Rhipidodonta rhombea — Simone (2006)

Ortmann, 1921. Mem. Carnegie Mus. 8: 531, pl. 38, figs. 5-7; pl. 46, fig. 7.
Type(s): LECTOTYPE CM_61.9264 (by R.I. Johnson, 1977: 237), Rio Grande, Boqueirao, Bahia, Brazil.
Diplodon (s.s.) enno — Ortmann (1921), Morretes (1949)
Diplodon delodontus enno — Haas (1930)
Diplodon rotundus — Bonetto (1962)
Diplodon (s.s.) delodontus enno — Bonetto (1964), Haas (1969)
Diplodon (s.s.) rotundus rotundus — Bonetto (1965)
Diplodon rotundus enno — Parodiz (1968)
Rhipidodonta rhombea — Simone (2006)

Haas, 1938. Arch. Moll. 70: 46, Abb. 1-3.
(intro'd as intra-sp. of Unio besckeanus Dunker, 1849)
Type(s): TYPE SMF_24362, Rio Sao Francisco, bei Jatoba, Staat Pernambuco, Bras.
Diplodon (s.s.) besckeanus nordestinus — Morretes (1949), Haas (1969)
Diplodon rhombeus — Parodiz (1968)
Rhipidodonta rhombea — Simone (2006)
Diplodon (s.s.) rhombeus — Simpson (1900), Simpson (1914), Pereira et al. (2014)
Diplodon (Cyclomya s.s.) patelloides — Simpson (1900), Simpson (1914)
Diplodon (s.s.) enno — Ortmann (1921), Morretes (1949)
Diplodon delodontus enno — Haas (1930)
Diplodon (Cyclomya) rhombeus — Haas (1931)
Diplodon (s.s.) besckeanus nordestinus — Morretes (1949), Haas (1969)
Diplodon rotundus — Bonetto (1962)
Diplodon (s.s.) delodontus enno — Bonetto (1964), Haas (1969)
Diplodon (s.s.) rotundus rotundus — Bonetto (1965)
Diplodon rhombeus — Parodiz (1968), Mansur et al. (2020), Graf & Cummings (2021)
Diplodon paranensis — Parodiz (1968), Quintana (1982)
Diplodon rotundus enno — Parodiz (1968)
Diplodon (Rhipidodonta) rhombeus — Haas (1969)
Rhipidodonta rhombea — Simone (2006), Graf & Cummings (2007), Bogan (2010)
Diplodon rhombea — ITIS (2013)