Unio cicatricosus Say, 1829
Say, 1829. New Harm. Dissem. 2(19): 292, sp. 2.
Say, 1858. [in] Binney, Compl. Writings T. Say: 131.
Type(s): NEOTYPE SMF_4539, N. Amerika.

Pleurobema (sec. Plethobasus) cicatricosa — Simpson (1900)
Pleurobema (sec. Plethobasus) cicatricosum — Simpson (1914)
Plethobasus cyphyus — Ortmann & Walker (1922), Burch (1975)
Pleurobema (Plethobasus) cyphyum — Frierson (1927)
Pleurobema (Plethobasus) cicatricosum — Haas (1930)
Plethobasus cicatricosus — Haas (1969), Stansbery (1970), R.I. Johnson (1980), Turgeon et al. (1988), Cummings & Mayer (1992), ... Haag (2012), Williams et al. (2017), Graf & Cummings (2021), FMCS (2021), Hopper et al. (2023)
Plethobasus pachosteus — Morrison (1969)

Unio varicosus Lea, 1831
Lea, 1831. Trans. Amer. Phil. Soc. 4 [O. 1]: 90 [100], pl. 11, fig. 20.
(homonym of Unio varicosa Lamarck, 1819)
Type(s): HOLOTYPE USNM_84320, Cincinnati, Ohio.

Pleurobema (sec. Plethobasus) cicatricosa — Simpson (1900)
Unio (s.s.) varicosus — Call (1900)
Pleurobema (sec. Plethobasus) cicatricosum — Simpson (1914)
Unio varicosus, var. — de Gregorio (1914)
Plethobasus cyphyus — Ortmann & Walker (1922), Burch (1975)
Pleurobema (Plethobasus) detectum — Frierson (1927)
Plethobasus cicatricosus — Haas (1969), Parmalee & Bogan (1998), Williams et al. (2008), Watters et al. (2009), IUCN (2011)

Unio cicatricoides Frierson, 1911
Frierson, 1911. Nautilus 25(5): 53, fig. 2, upper fig.
Type(s): HOLOTYPE UMMZ_80521, Wabash River, Indiana.

Pleurobema (sec. Plethobasus) cicatricosum — Simpson (1914)
Pleurobema (Plethobasus) cicatricoideum [sic] — Frierson (1927)
Plethobasus cicatricosus — Haas (1969), Parmalee & Bogan (1998), Williams et al. (2008), Watters et al. (2009)

Unio detectus Frierson, 1911
Frierson, 1911. Nautilus 25(5): 52, pls. 2 , lower fig.; pl. 3, upper fig.
Frierson, 1927. Check List N. Amer. Naiades: 45, sp. 202.
Type(s): HOLOTYPE UMMZ_81937, Ohio River.

Pleurobema (sec. Plethobasus) cicatricosum — Simpson (1914)
Pleurobema (Plethobasus) detectum — Frierson (1927)
Plethobasus cicatricosus — Haas (1969), Parmalee & Bogan (1998), Williams et al. (2008), Watters et al. (2009), IUCN (2011)

Plethobasus pachosteus Morrison, 1969
‘Rafinesque’ of Authors.
Morrison, 1969. AMU Annual Rept. (1969): 24.
R.I. Johnson, 1980. Bull. MCZ 149(2): 90.
(misidentified reference to Obovaria pachostea Rafinesque, 1820)

Plethobasus cicatricosus — Parmalee & Bogan (1998), Watters et al. (2009), IUCN (2011)

Unio cicatricosus Reeve, 1864
Reeve, 1864. Conch. Icon. 16: pl. 8, sp. 31; pl. 13, fig. 50.
(reference to Unio cicatricosus Say, 1829)

Pleurobema (sec. Plethobasus) cicatricosa — Simpson (1900)

Pleurobema (Plethobasus) cicatricoideum Frierson, 1927
Frierson, 1927. Check List N. Amer. Naiades: 45, sp. 203.
(error for Unio cicatricoides Frierson, 1911)