Bivalvia | Unionida | Unionoidea | Unionidae | Ambleminae | Amblemini | Reginaia
4 specimens + 5 GenBank vouchers
(new name for Obovaria pachostea Rafinesque, 1820)
Rafinesque, 1820. Ann. Gén. Sci. Phys. 5 (13): 322.
Rafinesque, 1864. [in] Binney & Tryon, reprint: 64.
Quadrula (Fusconia [sic]) antrosa — Frierson (1927)
Fusconaia antrosa — Haas (1969)
Amblema antrosa — Burch (1975)
Fusconaia ebena — Vidrine (1993), Parmalee & Bogan (1998), Williams et al. (2008), Watters et al. (2009), He & Zhuang (2013)
Rafinesque, 1818. Amer. Mon. Mag. 3: 355 [as ‘Potamilus pusillus’]. [nomen nudum]
Rafinesque, 1820. Ann. Gén. Sci. Phys. 5 (13): 308 [also as ‘Unio pusilla’].
Rafinesque, 1864. [in] Binney & Tryon, reprint: 23, 52.
Unio buxeus — Vanatta (1915)
Fusconaia pusilla — Morrison (1969)
Obliquaria pusilla — Burch (1975)
Fusconaia ebena — R.I. Johnson (1980), He & Zhuang (2013)

Rafinesque, 1818. Amer. Mon. Mag. 3: 355 [as ‘Potamilus obovalis’]. [nomen nudum]
Rafinesque, 1819. Jour. Phys. Chim. Hist. Nat. 88: 426 [as ‘U. (Obovaria) obovalis’]. [nomen nudum]
Rafinesque, 1820. Ann. Gén. Sci. Phys. 5 (13): 311 [also as ‘Unio obovalis’].
Rafinesque, 1864. [in] Binney & Tryon, reprint: 23, 29, 54.
Type(s): LECTOTYPE ANSP_20244, Ohio River.
Quadrula obovalis — Vanatta (1915)
Fusconaia ebenus — Ortmann & Walker (1922)
Quadrula (Fusconia [sic]) antrosa — Frierson (1927)
Fusconaia antrosa — Haas (1969)
Obovaria obovalis — Burch (1975)
Fusconaia ebena — Oesch (1984), Parmalee & Bogan (1998), Williams et al. (2008), Watters et al. (2009), He & Zhuang (2013)
(renamed Amblema antrosa Rafinesque, 1820)
Rafinesque, 1820. Ann. Gén. Sci. Phys. 5 (13): 312 [also as ‘U. pachostea’].
Rafinesque, 1864. [in] Binney & Tryon, reprint: 55.
Quadrula (Fusconia [sic]) antrosa — Frierson (1927)
Fusconaia antrosa — Haas (1969)
“Plethobasus pachosteus” ** — Morrison (1969)
Obovaria pachostea — Burch (1975)
“Plethobasus cicatricosus” ** — R.I. Johnson (1980)
Fusconaia ebena — Parmalee & Bogan (1998), Williams et al. (2008), Watters et al. (2009), He & Zhuang (2013)

Lea, 1831. Trans. Amer. Phil. Soc. 4 [O. 1]: 84 [94], pl. 9, fig. 14.
Type(s): HOLOTYPE USNM_85792, Cincinnati, Ohio.
Quadrula (sec. Fusconaia) ebenus — Simpson (1900)
Unio (s.s.) ebenus — Call (1900)
Fusconaia ebenus — Ortmann (1912), Ortmann & Walker (1922), Ortmann (1925), F.C. Baker (1928), Burch (1975), Mathiak (1979)
Quadrula (sec. Fusconaia) (Group of Q. subrotunda) ebenus — Simpson (1914)
Unio ebenus, var. — de Gregorio (1914)
Fusconaia ebena — Utterback (1915), Gordon et al. (1979), R.I. Johnson (1980), Davis & Fuller (1981), Oesch (1984), ... Breton et al. (2011), ITIS (2012), IUCN (2012), McMurray et al. (2012), He & Zhuang (2013)
Quadrula obovalis — Vanatta (1915)
Quadrula (Fusconia [sic]) antrosa — Frierson (1927)
Fusconaia antrosa — Haas (1969)
Fusconaia pusilla — Morrison (1969)
Reginaia ebenus — Campbell & Lydeard (2012), Campbell & Lydeard (2012), Inoue et al. (2013), Williams et al. (2017), Zieritz et al. (2018), ... FMCS (2021), Hopper et al. (2023), FMCS (2025), Campbell & Lydeard (2026), Barraza et al. (2026)
Reginaia ebena — Haag (2012), Pfeiffer et al. (2016), Chase et al. (2018), Pfeiffer et al. (2019), Pfeiffer et al. (2019), Inoue et al. (2020), Hauck et al. (2023)
(reference to Obovaria obovalis Rafinesque, 1820)
Say, 1834. Amer. Conch. 6: [unpaginated].
Quadrula (sec. Fusconaia) ebenus — Simpson (1900)
Quadrula (sec. Fusconaia) (Group of Q. subrotunda) ebenus — Simpson (1914)
Fusconaia ebena — Watters et al. (2009), He & Zhuang (2013)
(error for Obovaria obovalis Rafinesque, 1820)
‘Raf.’ Conrad, 1834. New Fresh-Water Shells: 69.
Pleurobema cordata — Ortmann & Walker (1922)
(misidentified reference to Unio obliqua Lamarck, 1819)
‘Lamarck’ of Authors.
Ferussac, 1835. Mag. Zool. 5(59-60): 28.
Conrad, 1837. Monogr. Fam. Unionidae 1(9): 77, pl. 43, fig. 2.
Quadrula (sec. Fusconaia) ebenus — Simpson (1900)
Quadrula (sec. Fusconaia) (Group of Q. subrotunda) ebenus — Simpson (1914)
Quadrula (Fusconia [sic]) antrosa — Frierson (1927)
Fusconaia antrosa — Haas (1969)
Fusconaia ebena — Parmalee & Bogan (1998), Watters et al. (2009)
(misidentified reference to Unio globatus Lea, 1871)
Call, 1894. Proc. Indiana Acad. Sci. 1893(3): ??.
Quadrula (Fusconia [sic]) antrosa — Frierson (1927)
(misidentified reference to Unio subrotundus Lea, 1831)
‘Lea’ Call, 1894. Proc. Indiana Acad. Sci. 1893(3): ??.
Quadrula (Fusconia [sic]) antrosa — Frierson (1927)
(error for Obliquaria (Rotundaria) pusilla Rafinesque, 1820)
‘Rafinesque’ Lea, 1836. Synopsis Fam. Naiades: 59.
‘Rafinesque’ Lea, 1852. Synopsis Fam. Naiades: 58.
‘Rafinesque’ Lea, 1870. Synopsis Fam. Naiades: 92.
Fusconaia ebena — He & Zhuang (2013)
(error for Unio (s.s.) mytiloides Swainson, 1840)
Swainson, 1840. Treat. Malacol.: 292.
(misidentified reference to Pleurobema mytiloides Rafinesque, 1820)
‘Rafinesque’ Swainson, 1840. Treat. Malacol.: 269-270, figs. 52-53; 292 [as ‘mytilïodes’].
Quadrula (sec. Fusconaia) ebenus — Simpson (1900)
Quadrula (sec. Fusconaia) (Group of Q. subrotunda) ebenus — Simpson (1914)
Quadrula (Fusconia [sic]) antrosa — Frierson (1927)
Fusconaia ebena — Parmalee & Bogan (1998), Watters et al. (2009)
Quadrula (sec. Fusconaia) ebenus — Simpson (1900)
Unio (s.s.) ebenus — Call (1900)
Fusconaia ebenus — Ortmann (1912), Ortmann & Walker (1922), Ortmann (1925), F.C. Baker (1928), Burch (1975), Mathiak (1979)
Quadrula (sec. Fusconaia) (Group of Q. subrotunda) ebenus — Simpson (1914)
Unio ebenus, var. — de Gregorio (1914)
Unio buxeus — Vanatta (1915)
Quadrula obovalis — Vanatta (1915)
Fusconaia ebena — Utterback (1915), Gordon et al. (1979), R.I. Johnson (1980), Davis & Fuller (1981), Oesch (1984), ... Breton et al. (2011), ITIS (2012), IUCN (2012), McMurray et al. (2012), He & Zhuang (2013)
Pleurobema cordata — Ortmann & Walker (1922)
Quadrula (Fusconia [sic]) antrosa — Frierson (1927)
Fusconaia antrosa — Haas (1969)
Fusconaia pusilla — Morrison (1969)
“Plethobasus pachosteus” ** — Morrison (1969)
Amblema antrosa — Burch (1975)
Obliquaria pusilla — Burch (1975)
Obovaria obovalis — Burch (1975)
Obovaria pachostea — Burch (1975)
“Plethobasus cicatricosus” ** — R.I. Johnson (1980)
Reginaia ebenus — Campbell & Lydeard (2012), Campbell & Lydeard (2012), Inoue et al. (2013), Williams et al. (2017), Zieritz et al. (2018), ... FMCS (2021), Hopper et al. (2023), FMCS (2025), Campbell & Lydeard (2026), Barraza et al. (2026)
Reginaia ebena — Haag (2012), Pfeiffer et al. (2016), Chase et al. (2018), Pfeiffer et al. (2019), Pfeiffer et al. (2019), Inoue et al. (2020), Hauck et al. (2023)