Revalidation and redescription of Moenkhausia madeirae Fowler from the rio Madeira basin in Brazil and Bolivia (Characiformes: Characidae)

Abstract

Based on the examination of type and recently collected specimens, Moenkhausia lepidura madeirae Fowler is resurrected from the synonymy of M. intermedia and redescribed as a valid species. Moenkhausia madeirae can be diagnosed from all congeners by the following combination of characters: presence of two symmetrical dark blotches on caudal fin (one on each lobe), a conspicuous humeral blotch, 18-22 branched anal-fin rays, and mature males with two (rarely three) well-developed hooks on the last simple and first branched anal-fin rays, respectively. The species occurs in the middle and upper rio Madeira basin in Brazil and Bolivia. Comparisons are made with the other species of Moenkhausia presenting symmetrical dark blotches on the caudal-fin lobes, i.e., M. barbouri, M. bonita, M. dichroura, and M. intermedia.