Conrad, T.A. 1841. [Descriptions of three new species of Unio from the rivers of the United States.] . Proceedings of the Academy of Natural Sciences of Philadelphia 1: 19-20. Available electronically.

Conrad, 1841. Proc. Acad. Nat. Sci. 1: 19.
Conrad, 1850. Jour. Acad. Nat. Sci. 1: 277, pl. 38, figs. 4, 8.
Conrad, 1853. Proc. Acad. Nat. Sci. 6: 253.
Type(s): LECTOTYPE ANSP_10285, Jackson, La.
Conrad, 1841. Proc. Acad. Nat. Sci. 1: 20.
(incorrect original spelling of Unio parallelus Conrad, 1841)
Conrad, 1841. Proc. Acad. Nat. Sci. 1: 20 [as ‘paralellus’].
Conrad, 1854. Jour. Acad. Nat. Sci. 2(4): 297 [as ‘parallelus’].
(renamed Unio porrectus Conrad, 1854; homonym of Unio parallelus Sowerby, 1840; correct name for Unio paralellus Conrad, 1841)

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.