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), ... Matos et al. (2024), Dai et al. (2025), Freeman et al. (2025), Chen et al. (2025), FMCS (2025)
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)
Barnes, 1823. Amer. J. Sci. 6 (1-2): 120, pl. 2, fig. 2a-b.
(homonym of Unio undulata Say, 1817)
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)
‘Rafinesque’ of Authors.
Conrad, 1836. Monogr. Fam. Unionidae 1(2): pl. 17, fig. 7.
Reeve, 1864. Conch. Icon. 16: pl. 4, sp. 16.
(reference to Amblema costata Rafinesque, 1820)
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)
‘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.
(error for Unio hippopoeus Lea, 1845)
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)
‘Say’ of Authors.
Küster, 1856. Conchyl. Cab. 9(2): 137, pl. 40, fig. 3.
Chenu, 1859. Manuel Conchyl. 2: 143, pl. 706.
(reference to Unio plicata Say, 1817)
Quadrula (sec. Crenodonta) undulata — Simpson (1900), Simpson (1914)
Strophitus undulatus — Vidrine (1993)
Amblema plicata — He & Zhuang (2013)
‘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.
(error for Unio latecostatus Lea, 1845)
Quadrula (sec. Crenodonta) undulata var. latecostata — Simpson (1900), Simpson (1914)
‘Conrad’ of Authors.
Reeve, 1864. Conch. Icon. 16: pl. 11, sp. 42.
Paetel, 1890. Cat. Conch.-Samml. 3: 163.
(error for Unio pearlensis Conrad, 1855)
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)
Desh. of Authors.
(misidentified reference to Unio multiplicatus Lea, 1831)
Desh. of Authors.
(reference to Unio undulatus Barnes, 1823)
‘Say’ Barnes, 1823. Amer. J. Sci. 6 (1-2): 118, figs. 1a-b.
(misidentified reference to Unio crassus Say, 1817)
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)
‘Barnes’ Lea, 1838. Trans. Amer. Phil. Soc. 6 [O. 2]: 31, 35.
(misidentified reference to Unio crassus var. giganteus Barnes, 1823)
Quadrula (sec. Crenodonta) plicata — Simpson (1900), Simpson (1914)
Amblema plicata — Parmalee & Bogan (1998), He & Zhuang (2013)
Amblema plicata plicata — Watters et al. (2009)
‘Barnes’ Hanley, 1843. Illustr. Descr. Cat. Rec. Bivalve Shells: 175, pl. 20, fig. 26.
(reference to Unio undulatus Barnes, 1823)
Quadrula (sec. Crenodonta) undulata — Simpson (1900), Simpson (1914)
Amblema costata — Ortmann (1924), F.C. Baker (1928)
Amblema plicata — Parmalee & Bogan (1998), He & Zhuang (2013)
Lea, 1852. Synopsis Fam. Naiades: 21.
(error for Unio latecostatus Lea, 1845)
‘Say’ Küster, 1855. Conchyl. Cab. 9(2): 136, pl. 40, figs. 1-2.
(misidentified reference to Unio heros Say, 1829)
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)
‘Conrad, Anthony, MS.’ Reeve, 1864. Conch. Icon. 16: pl. 9, sp. 35; errata [changed to ‘U. atrocostatus’].
(reference to Unio perplicatus Conrad, 1841; error for Unio atrocostatus Lea, 1845)
Unio (s.s.) multiplicatus — Call (1900)
Quadrula (sec. Crenodonta) perplicata — Simpson (1900)
‘Cragin’ B.H. Wright, 1888. Check List N. Amer. Unionidae etc.: [3].
(error for Unio quintardii Cragin, 1887)
‘Lea’ Paetel, 1890. Cat. Conch.-Samml. 3: 157.
(error for Unio lincecumii Lea, 1868)
Quadrula (sec. Crenodonta) perplicata — Simpson (1900), Simpson (1914)
Amblema plicata plicata — Watters et al. (2009)
Quadrula (sec. Crenodonta) plicata — Simpson (1900), Simpson (1914)
Unio (s.s.) plicatus — Call (1900)
Quadrula (sec. Crenodonta) undulata — Simpson (1900), Simpson (1914)
Unio (s.s.) undulatus — Call (1900)
Quadrula (sec. Crenodonta) perplicata — Simpson (1900), Simpson (1914)
Quadrula (sec. Crenodonta) plicata var. hippopæa [sic] — Simpson (1900), Simpson (1914)
Quadrula (sec. Crenodonta) undulata var. latecostata — Simpson (1900), Simpson (1914)
Unio (s.s.) multiplicatus — Call (1900)
Quadrula (sec. Crenodonta) perplicata var. quintardii — Simpson (1900), Simpson (1914)
Quadrula (sec. Crenodonta) undulata var. pilsbryi — Simpson (1900), Simpson (1914)
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 (plicata) costata — Utterback (1915)
Quadrula costata — Vanatta (1915)
Amblema perplicata — Utterback (1915), Davis & Fuller (1981), Lydeard et al. (1996), Krebs et al. (2003)
Amblema perplicata quintardi — Utterback (1915)
Amblema plicata costata — Ortmann (1918), Haas (1969)
Amblema plicata — Ortmann & Walker (1922), Modell (1942), R.I. Johnson (1969), Heard & Guckert (1970), Clarke (1973), ... Matos et al. (2024), Dai et al. (2025), Freeman et al. (2025), Chen et al. (2025), FMCS (2025)
Amblema costata — Ortmann & Walker (1922), Ortmann (1924), Ortmann (1925), F.C. Baker (1928), Thiele (1934), MacNeil (1935), ITIS (2012)
Megalonaias gigantea — Ortmann & Walker (1922), F.C. Baker (1928), Burch (1975)
Amblema perplicatus — Ortmann (1923)
Amblema (s.s.) plicata — Frierson (1927), Haas (1930)
Amblema (s.s.) plicata-costata — Frierson (1927)
Quadrula (Fusconia [sic]) subrotunda — Frierson (1927)
Amblema (Megalonaias) gigantea — Frierson (1927)
Amblema (s.s.) plicata-perplicata — Frierson (1927)
Amblema (s.s.) plicata-hippopaea [sic] — Frierson (1927)
Amblema (s.s.) plicata-quintardi — Frierson (1927)
Amblema (s.s.) plicata-pilsbryi — Frierson (1927)
Amblema (s.s.) plicata-southalli — 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)