Weakly rhomboidal disc, width less than 70% total length; rather long tail, postcoacal length more than 75% of disc length; short head (ventral length mostly less than 30% total length) and snout (length to eye less than 15% total length); narrow, cartilaginous interorbit less than 4% total length; internasal flap greatly expanded posteriorly; no broad lobes on posterolateral border of nostrils; inner margin of spiracle oblique; no lateral tail folds; no dorsal fin; apices of pelvic fins rounded; 7-8 oral papillae arranged along a 'W' line on mouth floor; 96-102 pectoral fin radials; total vertebrae more than 150; dorsal surface uniform yellowish brown (Ref. 51067).