Bivalvia | Unionida | Unionoidea | Unionidae | Ambleminae | Pleurobemini | Pleurobema
5 specimens + 6 GenBank vouchers

Lea, 1831. Trans. Amer. Phil. Soc. 4 [O. 1]: 92 [102], pl. 12, fig. 23.
Type(s): HOLOTYPE USNM_84723, Claiborne, Ala.
Pleurobema (s.s.) decisa — Simpson (1900)
Unio (s.s.) clavus — Call (1900)
Pleurobema decisum — Ortmann (1912), Burch (1975), Turgeon et al. (1988), Williams et al. (1993), Turgeon et al. (1998), ... Morrison et al. (2021), Hopper et al. (2023), Hauck et al. (2023), FMCS (2025), Campbell & Lydeard (2026)
Pleurobema (s.s.) decisum — Simpson (1914)
Pleurobema (s.s.) decisus — Frierson (1927)
Pleurobema decisum decisum — Haas (1969)
Pleurobema decisus — Jones et al. (2005)
Say, 1834. Amer. Conch. 6: ??.
(misidentified reference to Obliquaria (Scalenaria) scalenia Rafinesque, 1820)
Pleurobema (s.s.) decisa — Simpson (1900)
Pleurobema (s.s.) decisum — Simpson (1914)
Pleurobema (s.s.) decisus — Frierson (1927)

Lea, 1858. Proc. Acad. Nat. Sci. 10: 166.
Lea, 1859. Jour. Acad. Nat. Sci. 4 [O. 7]: 209 [27], pl. 25, fig. 90.
Type(s): HOLOTYPE USNM_84729, Chattanooga, Tenn.
Pleurobema (s.s.) chattanoogaensis — Simpson (1900)
Unio (s.s.) clavus — Call (1900)
Pleurobema (s.s.) chattanoogaense — Simpson (1914)
Pleurobema (s.s.) decisus-chattanoogaensis — Frierson (1927)
Pleurobema decisum chattanoogaensis — Haas (1969)
Pleurobema chattanogaense [sic] — Burch (1975)
Pleurobema chattanoogaense — Turgeon et al. (1988), Williams et al. (1993), Parmalee & Bogan (1998), Turgeon et al. (1998), Lydeard et al. (1999), ... Cummings & Graf (2010), ITIS (2012), Ouyang et al. (2015), Inoue et al. (2018), Morrison et al. (2021)
Pleurobema decisum — Williams et al. (2008), Williams et al. (2017), Graf & Cummings (2021)
Pleurobema chattanoogaensis — Hauck et al. (2023)

Lea, 1861. Proc. Acad. Nat. Sci. 13: 40.
Lea, 1862. Jour. Acad. Nat. Sci. 5 [O. 8]: 92 [96], pl. 13, fig. 240.
Type(s): HOLOTYPE USNM_84735, Columbus, Miss.
Pleurobema (s.s.) decisa — Simpson (1900)
Unio (s.s.) clavus — Call (1900)
Pleurobema (s.s.) decisum — Simpson (1914)
Unio anaticulus — de Gregorio (1914)
Pleurobema (s.s.) decisus — Frierson (1927)
Pleurobema decisum decisum — Haas (1969)
Pleurobema curtum — Williams et al. (2008)

Lea, 1861. Proc. Acad. Nat. Sci. 13: 60.
Lea, 1862. Jour. Acad. Nat. Sci. 5 [O. 8]: 67 [71], pl. 7, fig. 217.
Type(s): HOLOTYPE USNM_84726, Cahawba R., Ala.
Pleurobema (s.s.) decisa — Simpson (1900)
Unio (s.s.) clavus — Call (1900)
Pleurobema (s.s.) decisum — Simpson (1914)
Unio consanguineus — de Gregorio (1914)
Pleurobema (s.s.) decisus — Frierson (1927)
Pleurobema decisum decisum — Haas (1969)
Pleurobema decisum — Williams et al. (2008)

Lea, 1861. Proc. Acad. Nat. Sci. 13: 60.
Lea, 1866. Jour. Acad. Nat. Sci. 6 [O. 11]: 43 [47], pl. 15, fig. 41.
Type(s): HOLOTYPE USNM_84725, Coosawattee R., Ga.
Pleurobema (s.s.) decisa — Simpson (1900)
Unio (s.s.) clavus — Call (1900)
Pleurobema (s.s.) decisum — Simpson (1914)
Pleurobema (s.s.) decisus — Frierson (1927)
Pleurobema decisum decisum — Haas (1969)
Pleurobema decisum — Williams et al. (2008)
‘Lea’ Reeve, 1864. Conch. Icon. 16: pl. 17, sp. 77.
(misidentified reference to Unio medius Lea, 1861)
Pleurobema (s.s.) decisa — Simpson (1900)
Pleurobema (s.s.) decisum — Simpson (1914)
Pleurobema (s.s.) decisus — Frierson (1927)
Pleurobema decisum decisum — Haas (1969)
‘Lea’ Küster, 1852. Conchyl. Cab. 9(2): 41, pl. 7, fig. 3. [in part]
(reference to Unio decisus Lea, 1831)
Pleurobema (s.s.) decisa — Simpson (1900)
Pleurobema (s.s.) decisum — Simpson (1914)
‘Lea’ Burch, 1975. Freshw. Unio. North Amer.: 12.
(error for Unio chattanoogaensis Lea, 1858)
Pleurobema (s.s.) decisa — Simpson (1900)
Unio (s.s.) clavus — Call (1900)
Pleurobema (s.s.) chattanoogaensis — Simpson (1900)
Pleurobema decisum — Ortmann (1912), Burch (1975), Turgeon et al. (1988), Williams et al. (1993), Turgeon et al. (1998), ... Morrison et al. (2021), Hopper et al. (2023), Hauck et al. (2023), FMCS (2025), Campbell & Lydeard (2026)
Pleurobema (s.s.) decisum — Simpson (1914)
Pleurobema (s.s.) chattanoogaense — Simpson (1914)
Unio anaticulus — de Gregorio (1914)
Unio consanguineus — de Gregorio (1914)
Pleurobema (s.s.) decisus — Frierson (1927)
Pleurobema (s.s.) decisus-chattanoogaensis — Frierson (1927)
Pleurobema decisum decisum — Haas (1969)
Pleurobema decisum chattanoogaensis — Haas (1969)
Pleurobema chattanogaense [sic] — Burch (1975)
Pleurobema chattanoogaense — Turgeon et al. (1988), Williams et al. (1993), Parmalee & Bogan (1998), Turgeon et al. (1998), Lydeard et al. (1999), ... Cummings & Graf (2010), ITIS (2012), Ouyang et al. (2015), Inoue et al. (2018), Morrison et al. (2021)
Pleurobema decisus — Jones et al. (2005)
Pleurobema curtum — Williams et al. (2008)
Pleurobema chattanoogaensis — Hauck et al. (2023)