A new species of Nemuroglanis (Siluriformes: Heptapteridae) from the rio Guariba, rio Madeira basin, Brazil

Abstract

Nemuroglanis furcatus is described from streams of the rio Guariba, a clear water tributary of the rio Aripuanã, rio Madeira basin in Brazil. Nemuroglanis furcatus can be distinguished from its congeners by the possession of a long lateral line, reaching the middle portion of the adipose-fin base; a narrow posterior cranial fontanel (16 to 27% of its length); and the anterior border of pectoral bridge with a pointed contour. The plesiomorphic state of some of the synapomorphies for Nemuroglanis in N. furcatus suggests that this species might be the sister-group to the remaining species of the genus. A key for all four valid species of Nemuroglanis species is provided.