Bivalvia | Unionida | Unionoidea | Unionidae | Ambleminae | Amblemini | Amblema
14 specimens + 11 GenBank vouchers

‘LeSueur’ Say, 1817. Nich. Encyc. 2: [12].
‘LeSueur’ Say, 1819. Nich. Encyc. 4: [17].
Say, 1858. [in] Binney, Compl. Writings T. Say: 50.
Type(s): NEOTYPE SMF_4305, Ohio, U.S.A.
Quadrula (sec. Crenodonta) plicata — Simpson (1900), Simpson (1914)
Unio (s.s.) plicatus — Call (1900)
Crenodonta plicata — Ortmann (1912)
Amblema plicata — Ortmann & Walker (1922), Modell (1942), Heard & Guckert (1970), Clarke (1973), Burch (1975), ... Freeman et al. (2025), Chen et al. (2025), FMCS (2025), Campbell & Lydeard (2026), Wu et al. (2026)
Amblema (s.s.) plicata — Frierson (1927), Haas (1930)
Crenodonta peruviana peruviana — Murray & Leonard (1962)
Amblema plicata plicata — Haas (1969), Turgeon et al. (1988), Williams et al. (1993), Watters et al. (2009)
Amblema plicatus — Mackie et al. (1980)
Amblema p. plicata — Hoke (2005)
Bruguière, 1797. Encycl. Méth. 2: pl. 248, fig. 7 [as Unio sp.].
Lamarck, 1819. Hist. Natur. Anim. sans Vert. 6: 71, sp. 4.
Quadrula (sec. Crenodonta) plicata — Simpson (1900), Simpson (1914)
Amblema peruviana — Utterback (1915), Ortmann & Walker (1922), F.C. Baker (1928)
Amblema costata — Ortmann (1925)
Amblema (s.s.) plicata — Frierson (1927)
Crenodonta peruviana peruviana — Murray & Leonard (1962)
Amblema plicata plicata — Haas (1969), Watters et al. (2009)
Amblema plicata — Burch (1975), Mathiak (1979), R.I. Johnson (1980), Parmalee & Bogan (1998), Williams et al. (2008), He & Zhuang (2013)

Lamarck, 1819. Hist. Natur. Anim. sans Vert. 6: 71, sp. 5.
Type(s): HOLOTYPE MNHN_MPL_0037, Habite la rivière de l’Ohio. Michaud.
Quadrula (sec. Crenodonta) plicata — Simpson (1900), Simpson (1914)
Amblema rariplicata — Utterback (1915), F.C. Baker (1928)
Amblema plicata — Ortmann & Walker (1922), R.I. Johnson (1969), Burch (1975), R.I. Johnson (1980), Parmalee & Bogan (1998), Williams et al. (2008), He & Zhuang (2013)
Amblema (s.s.) plicata — Frierson (1927)
Amblema plicata plicata — Haas (1969), Watters et al. (2009)

Rafinesque, 1820. Ann. Gén. Sci. Phys. 5 (13): 315, pl. 82, figs. 13-14 [also as ‘Unio costata’].
Rafinesque, 1864. [in] Binney & Tryon, reprint: 58.
Type(s): LECTOTYPE ANSP_20246, small creeks, Kentucky.
Amblema (plicata) costata — Utterback (1915)
Quadrula costata — Vanatta (1915)
Amblema plicata costata — Ortmann (1918), Haas (1969)
Amblema costata — Ortmann & Walker (1922), Ortmann (1924), Ortmann (1925), F.C. Baker (1928), Thiele (1934), MacNeil (1935), ITIS (2012)
Amblema (s.s.) plicata-costata — Frierson (1927)
Crenodonta peruviana costata — Murray & Leonard (1962)
Amblema (s.s.) plicata costata — Haas (1969)
Amblema plicata — Heard & Guckert (1970), Clarke (1973), Burch (1975), R.I. Johnson (1980), Oesch (1984), ... Parmalee & Bogan (1998), Graf & Cummings (2007), Williams et al. (2008), He & Zhuang (2013), Graf & Cummings (2021)
Amblema plicata plicata — Watters et al. (2009)
(homonym of Unio undulata Say, 1817)
Barnes, 1823. Amer. J. Sci. 6 (1-2): 120, pl. 2, fig. 2a-b.
Quadrula (sec. Crenodonta) undulata — Simpson (1900), Simpson (1914)
Unio (s.s.) undulatus — Call (1900)
Quadrula undulata — Ortmann (1909), Ortmann (1909), Ortmann (1909), Ortmann (1910)
Crenodonta undulata — Ortmann (1912)
Unio undulatus — de Gregorio (1914)
Amblema (plicata) costata — Utterback (1915)
Quadrula costata — Vanatta (1915)
Megalonaias gigantea — Ortmann & Walker (1922), F.C. Baker (1928), Burch (1975)
Amblema costata — Ortmann & Walker (1922)
Amblema (Megalonaias) gigantea — Frierson (1927)
Crenodonta peruviana costata — Murray & Leonard (1962)
Amblema plicata — R.I. Johnson (1980), Oesch (1984), Vidrine (1993), Strayer & Jirka (1997), Williams et al. (2008), He & Zhuang (2013)
Megalonaias nervosa — Howells et al. (1996), Williams et al. (2008), Watters et al. (2009)
(reference to Amblema costata Rafinesque, 1820)
‘Rafinesque’ of Authors.
Conrad, 1836. Monogr. Fam. Unionidae 1(2): pl. 17, fig. 7.
Reeve, 1864. Conch. Icon. 16: pl. 4, sp. 16.
Quadrula (sec. Crenodonta) undulata — Simpson (1900), Simpson (1914)
Amblema plicata — He & Zhuang (2013)

Conrad, 1841. Proc. Acad. Nat. Sci. 1: 19.
Conrad, 1850. Jour. Acad. Nat. Sci. 1: 276, pl. 38, fig. 2.
Conrad, 1853. Proc. Acad. Nat. Sci. 6: 261 [as ‘Plectomerus perplicatus’].
Type(s): HOLOTYPE ANSP_129919, Jackson, Miss.
Quadrula (sec. Crenodonta) perplicata — Simpson (1900), Simpson (1914)
Crenodonta perplicata — Ortmann (1912), Ortmann (1914)
Amblema perplicata — Utterback (1915), Davis & Fuller (1981), Lydeard et al. (1996), Krebs et al. (2003)
Amblema perplicatus — Ortmann (1923)
Amblema costata — Ortmann (1924)
Amblema (s.s.) plicata-perplicata — Frierson (1927)
Amblema plicata costata — Haas (1969)
Amblema plicata — Burch (1975), R.I. Johnson (1980), Vidrine (1993), Howells et al. (1996), Parmalee & Bogan (1998), Williams et al. (2008), He & Zhuang (2013), Patterson et al. (2021)
Amblema plicata perplicata — Turgeon et al. (1988), Williams et al. (1993), Watters et al. (2009)
Amblema elliottii — Mulvey et al. (1997)
Lea, 1845. Proc. Amer. Phil. Soc. 4: 163.
Lea, 1848. Trans. Amer. Phil. Soc. 10 [O. 4]: 70 [44], pl. 2, fig. 5 [as ‘atro-costatus’].
Quadrula (sec. Crenodonta) perplicata — Simpson (1900), Simpson (1914)
Amblema (s.s.) plicata-perplicata — Frierson (1927)
Amblema plicata costata — Haas (1969)
Amblema plicata — Williams et al. (2008), He & Zhuang (2013)
Megalonaias nervosa — Watters et al. (2009)

Lea, 1845. Proc. Amer. Phil. Soc. 4: 163 [as ‘hippopœus’].
Lea, 1848. Trans. Amer. Phil. Soc. 10 [O. 4]: 67 [41], pl. 1, fig. 1 [as ‘hippopœus’].
Type(s): HOLOTYPE USNM_84096, L. Erie.
Quadrula (sec. Crenodonta) plicata var. hippopæa [sic] — Simpson (1900), Simpson (1914)
Quadrula hippopæa [sic] — Ortmann (1909)
Quadrula undulata hippopæa [sic] — Ortmann (1909)
Amblema (s.s.) plicata-hippopaea [sic] — Frierson (1927)
Amblema plicata costata — Haas (1969)
Amblema plicata — Clarke (1973), Burch (1975), Strayer & Jirka (1997), Parmalee & Bogan (1998), Williams et al. (2008), He & Zhuang (2013)
Amblema plicata plicata — Watters et al. (2009)

Lea, 1845. Proc. Amer. Phil. Soc. 4: 163.
Lea, 1848. Trans. Amer. Phil. Soc. 10 [O. 4]: 68 [42], pl. 1, fig. 2.
Type(s): POSSIBLE SYNTYPE ANSP_127444, Ala. River, Selma, Alabama.
Quadrula (sec. Crenodonta) undulata var. latecostata — Simpson (1900), Simpson (1914)
Amblema (s.s.) plicata-costata — Frierson (1927)
Amblema plicata — Howells et al. (1996), Williams et al. (2008), He & Zhuang (2013)
(error for Unio hippopoeus Lea, 1845)
‘Lea’ of Authors.
Lea, 1852. Synopsis Fam. Naiades: 21 [as ‘hippopæus’].
Conrad, 1853. Proc. Acad. Nat. Sci. 6: 261 [as ‘hippopæus’].
Adams & Adams, 1857. Gen. Rec. Moll. 2(31-32): 497 [as ‘hippopæus’].
Reeve, 1864. Conch. Icon. 16: pl. 11, sp. 40 [as ‘hippopæus’].
Lea, 1870. Synopsis Fam. Naiades: 31 [as ‘hippopæus’].
B.H. Wright, 1888. Check List N. Amer. Unionidae etc.: [3], [as ‘hippopæus’].
Simpson, 1900. Proc. U.S. Nat. Mus. 22: 767 [as ‘hippopæa’].
Ortmann, 1909. Nautilus 22(10): 101 [as ‘Q. hippopæa’].
Ortmann, 1909. Ann. Carnegie Mus. 5: 203 [as ‘Quadrula undulata hippopæa’].
Simpson, 1914. Descr. Cat. Naiades: 816 [as ‘hippopæa’].
Frierson, 1927. Check List N. Amer. Naiades: 61.
Haas, 1969. Das Tierreich 88: 287.
Clarke, 1973. Malacologia 13(1-2): 35.
Burch, 1975. Freshw. Unio. North Amer.: 165.
Strayer & Jirka, 1997. Pearly Mussels NY (26): 98.
He & Zhuang, 2013. Freshwater Bivalves China: 27.
Amblema plicata plicata — Watters et al. (2009)

Conrad, 1855. Proc. Acad. Nat. Sci. 7: 256.
Type(s): LECTOTYPE ANSP_129918, Pearl River, Miss.
Quadrula (sec. Crenodonta) perplicata — Simpson (1900), Simpson (1914)
Amblema (s.s.) plicata-perplicata — Frierson (1927)
Amblema plicata costata — Haas (1969)
Amblema plicata — Parmalee & Bogan (1998), Williams et al. (2008), He & Zhuang (2013)
Amblema plicata plicata — Watters et al. (2009)
(reference to Unio plicata Say, 1817)
‘Say’ of Authors.
Küster, 1856. Conchyl. Cab. 9(2): 137, pl. 40, fig. 3.
Chenu, 1859. Manuel Conchyl. 2: 143, pl. 706.
Quadrula (sec. Crenodonta) undulata — Simpson (1900), Simpson (1914)
Strophitus undulatus — Vidrine (1993)
Amblema plicata — He & Zhuang (2013)
(error for Unio latecostatus Lea, 1845)
‘Lea’ of Authors.
Adams & Adams, 1857. Gen. Rec. Moll. 2(31-32): 497.
Lea, 1870. Synopsis Fam. Naiades: 31.
Singley, 1893. Geol. Surv. Texas (1892): 317.
Quadrula (sec. Crenodonta) undulata var. latecostata — Simpson (1900), Simpson (1914)
(error for Unio pearlensis Conrad, 1855)
‘Conrad’ of Authors.
Reeve, 1864. Conch. Icon. 16: pl. 11, sp. 42.
Paetel, 1890. Cat. Conch.-Samml. 3: 163.
Quadrula (sec. Crenodonta) perplicata — Simpson (1900), Simpson (1914)
Amblema (s.s.) plicata-perplicata — Frierson (1927)
Amblema plicata — Parmalee & Bogan (1998)

Lea, 1868. Proc. Acad. Nat. Sci. 20: 144.
Lea, 1868. Jour. Acad. Nat. Sci. 6 [O. 12]: 309 [69], pl. 48, fig. 122.
Type(s): FIGURED SYNTYPE USNM_84110, Brazos River, Tex.
Quadrula (sec. Crenodonta) perplicata — Simpson (1900), Simpson (1914)
Amblema (s.s.) plicata-perplicata — Frierson (1927)
Amblema plicata costata — Haas (1969)
Amblema plicata — Parmalee & Bogan (1998), Williams et al. (2008), He & Zhuang (2013)
Amblema plicata plicata — Watters et al. (2009)

Lea, 1868. Proc. Acad. Nat. Sci. 20: 144.
Lea, 1868. Jour. Acad. Nat. Sci. 6 [O. 12]: 312 [72], pl. 49, fig. 125.
Type(s): FIGURED SYNTYPE USNM_84112, Dallas Co., Texas.
Quadrula (sec. Crenodonta) perplicata — Simpson (1900), Simpson (1914)
Amblema (s.s.) plicata-perplicata — Frierson (1927)
Amblema plicata costata — Haas (1969)
Amblema plicata — Parmalee & Bogan (1998), Williams et al. (2008), He & Zhuang (2013)
Amblema plicata plicata — Watters et al. (2009)

Lea, 1872. Proc. Acad. Nat. Sci. 24: 156.
Lea, 1874. Jour. Acad. Nat. Sci. 8 [O. 13]: 29 [33], pl. 9, fig. 26.
Type(s): FIGURED SYNTYPE USNM_84111, Austin, Texas.
Quadrula (sec. Crenodonta) perplicata — Simpson (1900), Simpson (1914)
Amblema (s.s.) plicata-perplicata — Frierson (1927)
Amblema plicata costata — Haas (1969)
Amblema plicata — Parmalee & Bogan (1998), Williams et al. (2008), He & Zhuang (2013)
Amblema plicata plicata — Watters et al. (2009)

Cragin, 1887. Bull. Washburn Coll. 2: 6.
Type(s): HOLOTYPE ANSP_63304, Sac & Fox Reservation, Oklahoma.
Quadrula (sec. Crenodonta) perplicata var. quintardii — Simpson (1900), Simpson (1914)
Amblema perplicata quintardi — Utterback (1915)
Amblema (s.s.) plicata-quintardi — Frierson (1927)
Amblema plicata costata — Haas (1969)
Amblema plicata — R.I. Johnson (1980), Parmalee & Bogan (1998), Williams et al. (2008), He & Zhuang (2013)
Amblema plicata plicata — Watters et al. (2009)

Marsh, 1891. Nautilus 5(1): 1.
Pilsbry, 1892. Proc. Acad. Nat. Sci. 44: 131, pl. 8, figs. 7-8.
Pilsbry, 1893. Nautilus 7(1): pl. 1, figs. 7-8.
Type(s): HOLOTYPE ANSP_41589, Little Red River, Ark.
Quadrula (sec. Crenodonta) undulata var. pilsbryi — Simpson (1900), Simpson (1914)
Amblema perplicata quintardi — Utterback (1915)
Amblema (s.s.) plicata-pilsbryi — Frierson (1927)
Amblema plicata costata — Haas (1969)
Amblema plicata — R.I. Johnson (1980), Parmalee & Bogan (1998), Williams et al. (2008), He & Zhuang (2013)
Amblema plicata plicata — Watters et al. (2009)

Marshall, 1916. Nautilus 29: 133.
Type(s): HOLOTYPE USNM_215130, James R., Huron, South Dakota.
Amblema (s.s.) plicata-southalli — Frierson (1927)
Amblema costata — Thiele (1934)
Amblema plicata costata — Haas (1969)
Cokeria southalli — Haas (1969)
Amblema plicata — R.I. Johnson (1980), Parmalee & Bogan (1998), Williams et al. (2008), He & Zhuang (2013)
Amblema plicata plicata — Watters et al. (2009)
(misidentified reference to Unio multiplicatus Lea, 1831)
Desh. of Authors.
(reference to Unio undulatus Barnes, 1823)
Desh. of Authors.
(misidentified reference to Unio crassus Say, 1817)
‘Say’ Barnes, 1823. Amer. J. Sci. 6 (1-2): 118, figs. 1a-b.
Quadrula (sec. Crenodonta) plicata — Simpson (1900), Simpson (1914)
Quadrula (Fusconia [sic]) subrotunda — Frierson (1927)
Amblema plicata plicata — Watters et al. (2009)
Amblema plicata — He & Zhuang (2013)
(misidentified reference to Unio crassus var. giganteus Barnes, 1823)
‘Barnes’ Lea, 1838. Trans. Amer. Phil. Soc. 6 [O. 2]: 31, 35.
Quadrula (sec. Crenodonta) plicata — Simpson (1900), Simpson (1914)
Amblema plicata — Parmalee & Bogan (1998), He & Zhuang (2013)
Amblema plicata plicata — Watters et al. (2009)
(reference to Unio undulatus Barnes, 1823)
‘Barnes’ Hanley, 1843. Illustr. Descr. Cat. Rec. Bivalve Shells: 175, pl. 20, fig. 26.
Quadrula (sec. Crenodonta) undulata — Simpson (1900), Simpson (1914)
Amblema costata — Ortmann (1924), F.C. Baker (1928)
Amblema plicata — Parmalee & Bogan (1998), He & Zhuang (2013)
(error for Unio latecostatus Lea, 1845)
Lea, 1852. Synopsis Fam. Naiades: 21.
(misidentified reference to Unio heros Say, 1829)
‘Say’ Küster, 1855. Conchyl. Cab. 9(2): 136, pl. 40, figs. 1-2.
Quadrula (sec. Crenodonta) plicata — Simpson (1900), Simpson (1914)
Amblema (s.s.) plicata — Frierson (1927)
Amblema plicata plicata — Haas (1969), Watters et al. (2009)
Amblema plicata — Parmalee & Bogan (1998)
(reference to Unio perplicatus Conrad, 1841; error for Unio atrocostatus Lea, 1845)
‘Conrad, Anthony, MS.’ Reeve, 1864. Conch. Icon. 16: pl. 9, sp. 35; errata [changed to ‘U. atrocostatus’].
Unio (s.s.) multiplicatus — Call (1900)
Quadrula (sec. Crenodonta) perplicata — Simpson (1900)
(error for Unio quintardii Cragin, 1887)
‘Cragin’ B.H. Wright, 1888. Check List N. Amer. Unionidae etc.: [3].
(error for Unio lincecumii Lea, 1868)
‘Lea’ Paetel, 1890. Cat. Conch.-Samml. 3: 157.
Quadrula (sec. Crenodonta) perplicata — Simpson (1900), Simpson (1914)
Amblema plicata plicata — Watters et al. (2009)
Quadrula (sec. Crenodonta) plicata — Simpson (1900), Simpson (1914)
Quadrula (sec. Crenodonta) plicata var. hippopæa [sic] — Simpson (1900), Simpson (1914)
Quadrula (sec. Crenodonta) perplicata — Simpson (1900), Simpson (1914)
Quadrula (sec. Crenodonta) perplicata var. quintardii — Simpson (1900), Simpson (1914)
Quadrula (sec. Crenodonta) undulata — Simpson (1900), Simpson (1914)
Quadrula (sec. Crenodonta) undulata var. latecostata — Simpson (1900), Simpson (1914)
Quadrula (sec. Crenodonta) undulata var. pilsbryi — Simpson (1900), Simpson (1914)
Unio (s.s.) undulatus — Call (1900)
Unio (s.s.) plicatus — Call (1900)
Unio (s.s.) multiplicatus — Call (1900)
Quadrula undulata — Ortmann (1909), Ortmann (1909), Ortmann (1909), Ortmann (1910)
Quadrula hippopæa [sic] — Ortmann (1909)
Quadrula undulata hippopæa [sic] — Ortmann (1909)
Crenodonta plicata — Ortmann (1912)
Crenodonta undulata — Ortmann (1912)
Crenodonta perplicata — Ortmann (1912), Ortmann (1914)
Unio undulatus — de Gregorio (1914)
Amblema peruviana — Utterback (1915), Ortmann & Walker (1922), F.C. Baker (1928)
Amblema rariplicata — Utterback (1915), F.C. Baker (1928)
Amblema perplicata — Utterback (1915), Davis & Fuller (1981), Lydeard et al. (1996), Krebs et al. (2003)
Amblema perplicata quintardi — Utterback (1915)
Amblema (plicata) costata — Utterback (1915)
Quadrula costata — Vanatta (1915)
Amblema plicata costata — Ortmann (1918), Haas (1969)
Megalonaias gigantea — Ortmann & Walker (1922), F.C. Baker (1928), Burch (1975)
Amblema costata — Ortmann & Walker (1922), Ortmann (1924), Ortmann (1925), F.C. Baker (1928), Thiele (1934), MacNeil (1935), ITIS (2012)
Amblema plicata — Ortmann & Walker (1922), Modell (1942), R.I. Johnson (1969), Heard & Guckert (1970), Clarke (1973), ... Freeman et al. (2025), Chen et al. (2025), FMCS (2025), Campbell & Lydeard (2026), Wu et al. (2026)
Amblema perplicatus — Ortmann (1923)
Quadrula (Fusconia [sic]) subrotunda — Frierson (1927)
Amblema (s.s.) plicata — Frierson (1927), Haas (1930)
Amblema (s.s.) plicata-costata — Frierson (1927)
Amblema (s.s.) plicata-perplicata — Frierson (1927)
Amblema (s.s.) plicata-hippopaea [sic] — Frierson (1927)
Amblema (s.s.) plicata-pilsbryi — Frierson (1927)
Amblema (s.s.) plicata-quintardi — Frierson (1927)
Amblema (s.s.) plicata-southalli — Frierson (1927)
Amblema (Megalonaias) gigantea — Frierson (1927)
Crenodonta peruviana peruviana — Murray & Leonard (1962)
Crenodonta peruviana costata — Murray & Leonard (1962)
Amblema plicata plicata — Haas (1969), Turgeon et al. (1988), Williams et al. (1993), Watters et al. (2009)
Amblema (s.s.) plicata costata — Haas (1969)
Cokeria southalli — Haas (1969)
Amblema plicatus — Mackie et al. (1980)
Amblema plicata perplicata — Turgeon et al. (1988), Williams et al. (1993), Watters et al. (2009)
Strophitus undulatus — Vidrine (1993)
Megalonaias nervosa — Howells et al. (1996), Williams et al. (2008), Watters et al. (2009)
Amblema elliottii — Mulvey et al. (1997)
Amblema p. plicata — Hoke (2005)