nigricans, Hypostomus Castelnau [F. L.] 1855:44, Pl. 22 (fig. 1) [Animaux nouveaux or rares v. 2; ref. 766] Amazon River, Brazil. Holotype (unique): MNHN A-9576. Type catalog: Bertin & Estève 1950:14 [ref. 19575], Ferraris 2007:278 [ref. 29155] •Valid as Parancistrus nigricans (Castelnau 1855) -- (Isbrücker 1980:58 [ref. 2303], Burgess 1989:435 [ref. 12860]). •Synonym of Parancistrus aurantiacus (Castelnau 1855) -- (Rapp Py-Daniel 1989:239 [ref. 13470], Isbrücker 2001:28 [ref. 25653], Isbrücker 2002:19 [ref. 27178], Fisch-Muller in Reis et al. 2003:392 [ref. 27061], Rapp Py-Daniel & Zuanon 2005:571 [ref. 28565], Ferraris 2007:278 [ref. 29155]). Current status: Synonym of Parancistrus aurantiacus (Castelnau 1855). Loricariidae: Hypostominae. Habitat: freshwater.