The ichthyofauna of a poorly known area in the middle-southern Espinhaco mountain range, state of Minas Gerais, Brazil: diagnostics and identification keys Author dos Santos, Sergio Alexandre https://orcid.org/0000-0003-4340-4139 Museu Nacional, Universidade Federal do Rio de Janeiro, Departamento de Vertebrados, Quinta da Boa Vista s / n. CEP 20.940 - 040, Rio de Janeiro, RJ, Brazil sergio.pisces@gmail.com Author de Britto, Marcelo Ribeiro Museu Nacional, Universidade Federal do Rio de Janeiro, Departamento de Vertebrados, Quinta da Boa Vista s / n. CEP 20.940 - 040, Rio de Janeiro, RJ, Brazil text ZooKeys 2021 2021-08-03 1054 25 66 http://dx.doi.org/10.3897/zookeys.1054.67554 journal article http://dx.doi.org/10.3897/zookeys.1054.67554 1313-2970-1054-25 BAEC60898F874A56BAD08E2922E22F60 C0E2746E8DE65F77826FCC7FF2B54A4C Brycon opalinus (Cuvier, 1819) Distribution. Rio Paraiba do Sul and rio Doce basins. Diagnosis. Brycon opalinus is diagnosed from its congeners by having one humeral spot and another in the caudal peduncle, never extending up to median caudal fin rays; tubules of the lateral line without secondary branches.