arcuatus, Corydoras Elwin [M. G.] 1938:126, Pl. 3 [Annals and Magazine of Natural History (Series 11) v. 3 (no. 13); ref. 17186] Amazon River (aquarium specimen). Holotype: BMNH 1939.3.3.1. Paratype: (1) lost. Type catalog: Ferraris 2007:113 [ref. 29155]. Nijssen & Isbrücker 1986:43 restricted the type locality, but that is not supported by the Code. •Valid as Corydoras arcuatus Elwin 1938 -- (Ovchynnyk 1967:36 [ref. 37559], Nijssen & Isbrücker 1980:209 [ref. 6910], Burgess 1989:365 [ref. 12860], Isbrücker 2001:220 [ref. 26805], Reis in Reis et al. 2003:295 [ref. 27061], Britto & Lima 2003:89 [ref. 27314], Ferraris 2007:113 [ref. 29155], Britto et al. 2009:687 [ref. 30609], Barriga Salazar 2014:111 [ref. 35745], Tencatt & Ohara 2016:[12] [ref. 34353] as cf. arcuatus, Ottoni et al. 2016:132 [ref. 34756], DoNascimiento et al. 2017:72 [ref. 35633], Tencatt et al. 2019:[3] [ref. 36697], Bentley et al. 2021:189 [ref. 38185], Meza-Vargas et al. 2021:25 [ref. 39298]). Current status: Valid as Corydoras arcuatus Elwin 1938. Callichthyidae: Corydoradinae. Distribution: South America: middle Rio Juruá drainage (Brazil), Rio Javari drainage (Brazil / Peru) and streams north of Leticia (Colombia). Habitat: freshwater.