tricornis, Hopliancistrus Isbrücker [I. J. H.] & Nijssen [H.] 1989:543, Figs. 5-7 [Die Aquarien- und Terrarienzeitschrift (DATZ) v. 42 (no. 9); ref. 13622] Poça de Pedra on Rio Tapajós, São Luis, Pará State, Brazil. Holotype: MZUSP 22007. Paratypes: IRSNB 692 (20); MZUSP 24304 (7), 26837 (7), 27664 (6); ZMA 107873-75 (6, 6, 6), 120339 (19). Type catalog: Ferraris 2007:249 [ref. 29155]. •Valid as Hopliancistrus tricornis Isbrücker & Nijssen 1989 -- (Burgess & Finley 1996:169 [ref. 22901], Montoya-Burgos et al. 1998:367 [ref. 23850], Isbrücker 2001:28 [ref. 25653], Isbrücker 2002:18 [ref. 27178], Fisch-Muller in Reis et al. 2003:386 [ref. 27061], Ferraris 2007:249 [ref. 29155], Oliveira et al. 2021:4 [ref. 38080]). Current status: Valid as Hopliancistrus tricornis Isbrücker & Nijssen 1989. Loricariidae: Hypostominae. Distribution: Middle Tapajós River basin (including lower Jamanxim and Itapacurá River drainages) and Cupari River drainage, Pará State, Brazil. Habitat: freshwater.