Redescription of the freshwater anchovy Anchoviella vaillanti (Steindachner, 1908) (Clupeiformes: Engraulidae) with notes on the distribution of estuarine congeners in the Rio São Francisco basin, Brazil

Abstract

Anchoviella vaillanti (Steindachner, 1908) was described based on few specimens from the middle Rio São Francisco; however, several specimens of the species have been collected in recent decades. The range of morphological variation of A. vaillanti could thus be reassessed based on a larger number of specimens currently available in fish collections, and the species redescribed. Anchoviella vaillanti can be recognized among freshwater congeners by the relative position of the pelvic, dorsal and anal fins. Records of the species in ichthyological collections are restricted to the upper and middle portions of the Rio São Francisco basin, but the species might also occur in the lower Rio São Francisco. Comments on the distribution of the marine species of Anchoviella from the lower Rio São Francisco basin and an identification key including those species and A. vaillanti are provided.