It is triangular in shape, supported by a single root, and shows three main cusps, in addition to various crests.

Radula: The large main cusp of the central tooth is accompanied by very small ectocones.

In some cases, Carabelli's cusp may rival the main cusps in size.

The large main cusp of the central tooth of radula is accompanied by prominent ectocones.

In the first marginal tooth, the main cusp is less symmetrical and the basal plate is less prominently developed.

The main cusps are located opposite each other and have rounded edges.

The main cusp is protocone; among the other two cusps, the paracone is higher but the metacone larger.

The ridge pattern results in the presence of three transverse furrows between the main cusps.

The molars of both species possess several accessory crests in addition to the main cusps.

The paracone, one of the main cusps, is quite small; this cusp is more prominent in N. rufus.