Description of a new species of the genus Awaous Valenciennes, 1837 (Gobiiformes: Oxudercidae) from the middle stretch of the Mahanadi River, Odisha, India, with comments on the Awaous species from India.

Abstract

A new species of the genus Awaous (Oxudercidae), Awaous motla sp. nov., is described based on 18 specimens collected from the Mahanadi River near Sonepur, Subarnapur District, and 3 specimens from the same river near Boudh bridge, Boudh District of Odisha, India. This species is distinct from its congeners by having a combination of characteristics: relatively small eyes, diameter of 6.6-8.4 in head length (LH); robust and long snout, 2.0-2.6 in LH; eye diameter 2.7-4.1 in snout length; cephalic sensory pore system interrupted with eight pores; predorsal scales 13-15; longitudinal scale series 55-58; gill rakers 2 + 1 + (6-7) on the first gill arch; teeth small, conical, and in a single row on the upper jaw and multiserial (2-3) on the lower jaw. This species is also differentiated from some of its congeners in the nucleotide composition of the cytochrome c oxidase I gene by 8.3%-13.8% Kimura two-parameter (K2P) distance and belongs to a separate cluster in the maximum likelihood tree analysis. This finding is also supported by the species delimitation analysis based on Assemble Species by Automatic Partitioning. The new species holds high commercial value in its locality and needs special conservation attention for sustainable utilization.