Distinguished from the other two peninsular Indian species N. anguilla and N. monilis by its colouration and a set of morphometric characters. The species differs in having a lateral line that extends to the pelvic fin base below (vs. reaching up to anal fin in N. anguilla and complete in N. monilis), shorter snout length (35.9-39.4% HL vs 46.8% HL in N. anguilla and 40.5-48.1% HL in N. monilis), bigger eye (28.1-31.3% HL vs 23.0% HL in N. anguilla and 15.9-19.9% HL in N. monilis), caudal peduncle shorter than N. anguilla (12.4-13.1% SL vs 15.5% SL) and shallower than N. monilis (9.5-10.2% SL vs 12.0-14.5% SL). Vent to anal distance is reduced compared to N. anguilla (29.7-34.5% vs 40.6% Pelvic to anal distance) and greater than N. monilis (29.7-34.5% vs 16.9-25.9% Pelvic to anal distance). Notable colour variations are the lesser number of bands on dorsal (back) 11-13 (vs 19-20 in N. anguilla and N. monilis), 6-8 blotches evently spaced along the lateral line (vs. band formed of coalescing blotches extending to caudal base in N. anguilla and monoliform band in N. monilis (Ref. 80640).