gymnotus, Porotergus Ellis [M. D.] in Eigenmann 1912:441 [Memoirs of the Carnegie Museum v. 5 (no. 1); ref. 1227] Amatuk, Guyana. Holotype: FMNH 53575 [ex CM 1759]. Paratypes: BMNH 1911.10.31.543 (1), CAS 62305 [ex IU 12636] (1), FMNH 53291 [ex CM 1758] (1). Type catalog: Henn 1928:71 [ref. 12305], Ibarra & Stewart 1987:69 [ref. 12367], Ferraris et al. 2017:[10] [ref. 35236]. Also appeared in Ellis 1913:153, Pl. 23 (fig. 4) [ref. 1271]. •Valid as Porotergus gymnotus Ellis 1912 -- (Mago-Leccia 1994:32 [ref. 21320], Planquette et al. 1996:408 [ref. 22818], Albert & Campos-da-Paz 1998:433 [ref. 23853], Albert 2001:111 [ref. 25614], Albert in Reis et al. 2003:500 [ref. 27061], Cox Fernandes et al. 2009:204 [ref. 30178] as cf. gymnotus, de Santana & Crampton 2010:172 [ref. 30762], Sarmiento et al. 2014:188 [ref. 35004], Ferraris et al. 2017:[10] [ref. 35236], Bernt et al. 2018:474 [ref. 35797], Ochoa et al. 2020:63 [ref. 37781], Taphorn et al. 2022:38 [ref. 41297]). Current status: Valid as Porotergus gymnotus Ellis 1912. Apteronotidae: Apteronotinae. Distribution: South America: Essequibo and Amazon River basins (Bolivia, Brazil, French Guiana and Guyana). Habitat: freshwater.