johnii, Plecostomus Steindachner [F.] 1877:691 [133] [Sitzungsberichte der Kaiserlichen Akademie der Wissenschaften. Mathematisch-Naturwissenschaftliche Classe v. 74 (1. Abth.); ref. 4224] Rio Poti, rio Parnaíba basin, municipality of Teresina, Piauí, Brazil. Lectotype: MCZ 7831. Paralectotypes: MCZ 7863-64 (4, 2); NMW 44191-93 (2, 2, 2); USNM 123009 [ex MCZ 7831] (2). Type catalog: Ferraris & Vari 1992:31 [ref. 19771], Ferraris 2007:255 [ref. 29155] On p. 133 of separate. Lectotype selected by Ramos et al. 2017:6 [ref. 35396]. •Valid as Hypostomus johnii (Steindachner 1877) -- (Isbrücker 1980:25 [ref. 2303], Burgess 1989:431 [ref. 12860], Isbrücker 2001:28, 31 [ref. 25653], Isbrücker 2002:19 [ref. 27178], Weber in Reis et al. 2003:359 [ref. 27061], Armbruster 2004:79 [ref. 27644] dated 1876, Ferraris 2007:255 [ref. 29155], Zawadzki et al. 2012:246 [ref. 32031], Zanata et al. 2013:248 [ref. 32751], Ramos et al. 2014:4 [ref. 35321], Zawadzki et al. 2015:57 [ref. 33866], Zanata & Pitanga 2016:229 [ref. 34535], Zawadzki et al. 2017:12 [ref. 35355], Ramos et al. 2017:2 [ref. 35396], Zawadzki et al. 2017:571 [ref. 35666], Silva et al. 2020:11 [ref. 37809], Koerber et al. 2022:51 [ref. 39235], Lustosa-Costa et al. 2022:16 [ref. 39190]). Current status: Valid as Hypostomus johnii (Steindachner 1877). Loricariidae: Hypostominae. Distribution: South America: lower and middle Parnaíba River basin (Brazil). Habitat: freshwater.