butantanis, Plecostomus margaritifer Ihering [R. von] 1911:394 [Revista do Museo Paulista, São Paulo v. 8 (1910); ref. 14822] Rio Pinheiros, São Paulo State, Brazil. Holotype (unique): DZSASP [now MZUSP] (not found). Type catalog: Ferraris 2007:256 [ref. 29155]. •Synonym of Hypostomus margaritifer (Regan 1908) -- (Weber in Reis et al. 2003:360 [ref. 27061], Ferraris 2007:256 [ref. 29155]). •Valid as Hypostomus butantanis (Ihering 1911) -- (Isbrücker 1980:21 [ref. 2303], Burgess 1989:430 [ref. 12860], Isbrücker 2001:28, 31 [ref. 25653], Isbrücker 2002:18 [ref. 27178], Armbruster 2004:79 [ref. 27644]). •Synonym of Hypostomus variipictus (Ihering 1911) -- (Azevedo et al. 2021:3 [ref. 38203]). Current status: Synonym of Hypostomus variipictus (Ihering 1911). Loricariidae: Hypostominae. Distribution: Brazil [if valid]. Habitat: freshwater.