A new long-finned Corydoras Lacépède, 1803 (Siluriformes: Callichthyidae) from the lower rio Paraná basin, Brazil

Abstract

A new species of Corydoras is described from the lower rio Paraná basin, just downstream from Itaipu Dam, Brazil, close to Paraguay boundary. The new species can be distinguished from most of its congeners by the infraorbital 2 with a posterior laminar expansion conspicuously reduced, first and second dorsal-fin branched rays conspicuously elongated in males, mesethmoid entirely covered by skin, and by the presence of four to six irregular black or brownish blotches on the midline of the flank. The probable occurrence of the new species in the floodplain of the upper portion of the rio Paraná drainage is discussed.

Keywords

• Canal da Piracema
• Corydoradinae
• Itaipu dam
• Sexual dimorphism
• Taxonomy