Crosse, H. & P. Fischer. 1893. Diagnoses Molluscorum Republicae Mexicanae et Guatemalae incolarum. Journal de Conchyliologie 40: 294-296. Available electronically.

Crosse & Fischer, 1893. J. de Conch. 40: 295.
Fischer & Crosse, 1894. Miss. Sci. Mexique, Rech. Zool. 2(15): 518, pl. 64, figs. 8-11.
Type(s): SYNTYPES MNHN_IM-2000-1657, Mexique, Lac de Tchapala.
Crosse & Fischer, 1893. J. de Conch. 40: 294 [as ‘usumasintæ’].
Martens, 1900. Biol. Centr.-Amer., Moll.: 500 [as ‘usumacintæ’].
(new name for Unio usumasintae Crosse & Fischer, 1893)
Crosse & Fischer, 1893. J. de Conch. 40: 294 [as ‘usumasintæ’].
Fischer & Crosse, 1894. Miss. Sci. Mexique, Rech. Zool. 2(15): 574, pl. 63, fig. 4; pl. 67, fig. 5 [as ‘usumasintæ’].
(renamed Unio usumacintae Martens, 1900)
Type(s): TYPE LOST XXX_UNKNOWN, in flumine Usumasinta, Provinciæ Peten dictæ, Guatemalæ.

Crosse & Fischer, 1893. J. de Conch. 40: 294.
Fischer & Crosse, 1894. Miss. Sci. Mexique, Rech. Zool. 2(16): 597, pl. 64, figs. 4-4b.
Type(s): SYNTYPES MNHN_IM-2000-1810, Lac Yzabal, Guatemala.