hepsetus, Hydrocyon Cuvier [G.] 1829:312 [Le Règne Animal (Edition 2) v. 2; ref. 995] No locality stated [Rio de Janeiro, Brazil]. Non-types: MNHN A-9851 (3, poor condition) Buenos Aires. Type catalog: Bertin 1948:7-8 [ref. 19577] but dated to Valenciennes 1847. On Quoy & Gaimard 1824-25, pl. 48 (fig. 2) [ref. 3574]. •Valid as Acestrorhampus hepsetus (Cuvier 1829) -- (Haro et al. 1996:6 [ref. 25004]). •Valid as Oligosarcus hepsetus (Cuvier 1829) -- (Menezes & Géry 1983:589 [ref. 8307], Menezes 1987:31 [ref. 20060], Gómez & Chebez 1996:47 [ref. 23791], Menezes in Reis et al. 2003:151 [ref. 27061], Ribeiro et al. 2007:52 [ref. 29321], Di Dario et al. 2013:262 [ref. 37503], Catelani et al. 2014:931 [ref. 37496], Litz & Koerber 2014:15 [ref. 33622], Ribeiro & Menezes 2015:77 [ref. 33768], Mirande & Koerber 2015:25 [ref. 35117], Petry et al. 2016:302 [ref. 34966], Nión et al. 2016:28 [ref. 35565] with author as Steindachner 1867, Wendt et al. 2019:5 [ref. 36952], Koerber & Serra 2020:4 [ref. 37449], Mirande & Koerber 2020:2 [ref. 37594], Menezes & Camelier 2024:243 [ref. 40817]). Current status: Valid as Oligosarcus hepsetus (Cuvier 1829). Acestrorhamphidae: Acestrorhamphinae. Distribution: South America: Rio de Janeiro south to Laguna dos Patos (southeastern Brazil). Habitat: freshwater, brackish.