ambyiacus, Auchenipterus Fowler [H. W.] 1915:222, Fig. 6 [Proceedings of the Academy of Natural Sciences of Philadelphia v. 67; ref. 1392] Ambyiacu [Ampiyacu] River, Ecuador [now Peru]. Holotype (unique): ANSP 21484. Type catalog: Böhlke 1984:24 [ref. 13621], Ferraris 2007:71 [ref. 29155]. •Synonym of Auchenipterus nuchalis (Spix & Agassiz 1829) -- (Burgess 1989:241 [ref. 12860]). •Valid as Auchenipterus ambyiacus Fowler 1915 -- (Ferraris & Vari 1999:400 [ref. 23953], Ferraris in Reis et al. 2003:473 [ref. 27061], Ferraris 2007:71 [ref. 29155], Barriga Salazar 2014:115 [ref. 35745], Sarmiento et al. 2014:143, 189 [ref. 35004], DoNascimiento et al. 2017:86 [ref. 35633], Calegari et al. 2019:[96] [ref. 36961], Meza-Vargas et al. 2021:22 [ref. 39298]). Current status: Valid as Auchenipterus ambyiacus Fowler 1915. Auchenipteridae: Auchenipterinae. Distribution: South America: upper and middle Amazon and Orinoco River basins and coastal rivers of Guyana (Bolivia, Brazil, Colombia, Ecuador, Guyana, Peru and Venezuela). Habitat: freshwater.