agna, Plecostomus Miranda Ribeiro [A. de] 1907:188 [Boletim Sociedade Nacional Agricultura, Rio de Janeiro [Lavoura] v. 11 (no. 5); ref. 17767] Rio Ribeira, Iporanga, São Paulo, Brazil. Holotype (unique): whereabouts unknown. Type catalog: Ferraris 2007:251 [ref. 29155]. Originally as ãgnã. Not listed in Miranda Ribeiro 1953 [ref. 12732]. •Valid as Hypostomus agna (Miranda Ribeiro 1907) -- (Isbrücker 1980:18 [ref. 2303], Burgess 1989:430 [ref. 12860], Isbrücker 2001:28, 31 [ref. 25653], Isbrücker 2002:18 [ref. 27178], Weber in Reis et al. 2003:355 [ref. 27061], Armbruster 2004:79 [ref. 27644], Oyakawa et al. 2005:4 [ref. 28322], Ferraris 2007:251 [ref. 29155], Zawadzki et al. 2015:56 [ref. 33866], Reis et al. 2020:467 [ref. 38364]). Current status: Valid as Hypostomus agna (Miranda Ribeiro 1907). Loricariidae: Hypostominae. Distribution: South America: Ribeira de Iguapé River basin (Brazil). Habitat: freshwater.