A new species of Heptapterus Bleeker 1858 (Siluriformes, Heptapteridae) from the Rio Sali basin, north-western Argentina

A revision of fish specimens previously identified as Heptapterus mustelinus from the endorheic Rio Sali Basin, Tucuman, Argentina, reveals that they present several morphological differences from that species. This paper describes Heptapterus qenqo sp. nov. from the Rio Sali Basin. The new species is diagnosed by a combination of the following characters: presence of small serrae on the anterior proximal margin of the first pectoral-fin ray; anal-fin rays iv-v, 11-13 (15-17 total anal-fin rays); adipose-fin base 40.9-47.4% standard length; small eyes (7.4-14.2% head length); adipose-fin confluent to caudal fin and maxillary barbel not reaching pectoral-fin base in adults, and reaching or scarcely surpassing the first pectoral-fin ray in small juveniles. (C) 2010 The Authors