armatus, Hydrocyon Jardine [W.] in Schomburgk 1841:249, Pl. 25 [The Natural history of fishes of Guiana; ref. 18707] Sandbars in vicinity of Maipuri campsite, 4°34'N, 58°35'W, Essequibo River, Guyana. Neotype: ANSP 175725. Book contains 2 plates numbered 25, both of which are identified as Hydrocyon armatus. Neotype designated by Toledo-Piza et al. 1999:273 [ref. 24227]. •Valid as Hydrolycus armatus (Jardine 1841) -- (Toledo-Piza et al. 1999:267 [ref. 24227], Toledo-Piza in Reis et al. 2003:235 [ref. 27061], Sarmiento et al. 2014:67, 186 [ref. 35004], DoNascimiento et al. 2017:36 [ref. 35633], Urbano-Bonilla et al. 2018:83 [ref. 35773], Koerber et al. 2022:17 [ref. 39235]). Current status: Valid as Hydrolycus armatus (Jardine 1841). Cynodontidae. Distribution: South America: Amazon and Orinoco River basins and rivers of Guyana (Brazil, Bolivia, Colombia, Guyana and Venezuela). Habitat: freshwater.