Diagnosis: combined premaxillary tooth plate width rather large, 30.1-35.3% of head length vs. larger in N. macrostoma and smaller in N. akiri, N. pembetadi and much smaller in the other species except N. depierrei; interorbital distance small, 17.2-23.4% of head length vs. larger in N. akiri and over 27% in N. macrostoma, M. maculatum, N. thomasi and N. walkeri; eye diameter relatively large, 7.5-10.4% of head length, negatively allometric with body size, vs. smaller in N. pallidum and N. maculatum; only 7 soft dorsal-fin rays vs. more than 8 in N. depierrei, N. maculatum, N. pallidum, N. pembetadi, N. thomasi and N. walkeri (Ref. 94168).

Description: head and body extremely dorsoventrally flattened, with depth almost constant from head to body, predorsal body depth 10.9-12.9% of standard length, minimal caudal peduncle depth 10.0-11.0% of standard length, head depth 36.6-38.9% of head length; branchiostegal membranes almost not fused, separated by a deep medial slit, possibly overlapping; dorsal-fin spine short, 3.4-7.4% of standard length (Ref. 94168).

Colouration: In life, uniform brownish red, paler ventrally; in young specimens 5-7 pale vertical dotted bars may be visible on the flanks; most fins somewhat transparent (Ref. 94168).