Publication Frierson (1927): species taxonomic opinions

Frierson, L.S. 1927. A Classified and Annotated Check List of the North American Naiades. 111 pp. https://babel.hathitrust.org/cgi/pt?id=coo.31924002812125&view=1up&seq=3.

Quadrula (Quincuncina) securiformis (Conrad, 1849) = Pustulosa infucata + Pustulosa kleiniana

+ Unio infucatus Conrad, 1834

+ Unio liratus Shuttleworth, 1852

+ Unio sparsus Küster, 1861

Quadrula (Quincuncina) securiformis-kleiniana (Lea, 1853) = Pustulosa kleiniana

Quadrula (Quincuncina) vittata Frierson, 1927 = Glebula rotundata

+ Unio rotundatus Reeve, 1865

Quadrula (s.s.) conjugans (Wright, B.H., 1899) = Quadrula verrucosa

Quadrula (s.s.) quadrula (Rafinesque, 1820) = Quadrula quadrula

+ Unio rugosus Barnes, 1823

+ Unio lacrymosus Lea, 1828

+ Unio dombeyanus Barnes, 1828

+ Unio asperrimus Lea, 1831

+ Unio quadratus Reeve, 1864

+ Unio lunulatus Pratt, 1876

Quadrula (s.s.) quadrula-apiculata (Say, 1829) = Quadrula quadrula

Quadrula (s.s.) quadrula-aspera (Lea, 1831) = Quadrula quadrula + Quadrula verrucosa

+ Tritogonia tuberculata var. obesa Simpson, 1900

Quadrula (s.s.) quadrula-forsheyi (Lea, 1859) = Quadrula quadrula

Quadrula (s.s.) quadrula-fragosa (Conrad, 1836) = Quadrula fragosa

Quadrula (s.s.) quadrula-nobilis (Conrad, 1854) = Quadrula nobilis

Quadrula (s.s.) quadrula-rumphiana (Lea, 1852) = Quadrula quadrula

+ Unio blandianus Lea, 1857

Quadrula (s.s.) quadrula-speciosa (Lea, 1862) = Quadrula quadrula

Quadrula (Striata) striata (Rafinesque, 1820) = Obovaria subrotunda + Plethobasus cooperianus + Pustulosa kieneriana

+ Unio striatus Reeve, 1864

+ Unio cooperianus Lea, 1834

+ Unio asperatus Sowerby, 1868

Quadrula (Tritogonia) verrucosa (Rafinesque, 1820) = Quadrula verrucosa

+ Unio tuberculatus Barnes, 1823

+ Unio (Theliderma) pustulata Swainson, 1840

+ Unio gigas Sowerby, 1867

+ Quadrula parkeri Geiser, 1911

Simpsoniconcha ambigua (Say, 1825) = Simpsonaias ambigua

+ Unio hildrethianus Lea, 1834

+ Alasmidonta dubia Ferussac, 1835

Strophitus (Jugosus) wrightianus Walker, 1901 = Alasmidonta wrightiana

Strophitus (Pseudodontoideus) alabamensis (Lea, 1861) = Pseudodontoideus connasaugaensis

Strophitus (Pseudodontoideus) gesneri (Lea, 1858) = Pseudodontoideus subvexus

Strophitus (Pseudodontoideus) spillmani (Lea, 1858) = Pseudodontoideus subvexus

Strophitus (s.s.) connasaugaensis (Lea, 1858) = Pseudodontoideus connasaugaensis

Strophitus (s.s.) radiatus (Conrad, 1834) = Strophitus radiatus

+ Margaritana elliottii Lea, 1858

+ Anodonta showalterii Lea, 1860

+ Margaritana elliptica Lea, 1859

Strophitus (s.s.) subvexus (Conrad, 1834) = Pseudodontoideus subvexus

+ Margaritana tombigbeensis Lea, 1862

+ Margaritana columbensis Lea, 1867

Strophitus (s.s.) undulatus (Say, 1817) = Strophitus undulatus

+ Alasmodonta edentula Say, 1829

+ Anodon areolatus Swainson, 1829

+ Anodon unadilla De Kay, 1843

+ Anodonta arkansensis Lea, 1852

+ Anodonta tetragona Lea, 1845

+ Anodon papyracea J.G. Anthony, 1865

+ Anodonta shaefferiana Lea, 1852

+ Anodon quadriplicatus Sowerby, 1870

+ Alasmodon rhombica J.G. Anthony, 1865

+ Anodon annulatus Sowerby, 1867

Strophitus (s.s.) undulatus-ovatus Frierson, 1927 = Strophitus undulatus

Strophitus (s.s.) undulatus-pennsylvanicus [sic] (Say, 1817) = Strophitus undulatus

Strophitus (s.s.) undulatus-rugosus (Swainson, 1822) = Strophitus undulatus

Strophitus (s.s.) undulatus-tennesseensis Frierson, 1927 = Strophitus undulatus

Strophitus (s.s.) undulatus-virgatus (Conrad, 1836) = Strophitus undulatus

+ Anodonta wardiana Lea, 1838

+ Anodonta pavonia Lea, 1838

Truncilla cognata (Lea, 1860)

Truncilla donaciformis (Lea, 1828)

+ Unio zigzag Lea, 1829

+ Unio nervosa ‘Rafinesque’ of Authors

+ Unio ziczac ‘Lea’ of Authors

Truncilla macrodon (Lea, 1859)

Truncilla truncata Rafinesque, 1820

+ Unio elegans Lea, 1831

Truncilla truncata-vermiculata Rafinesque, 1820 = Truncilla truncata