Carenzia melvilli is a species of small deep water sea snails, a marine gastropod mollusk in the family Seguenziidae.

The upper one runs at a little distance from the shallow but distinct suture, which is slightly undulate.

This space is rather smooth, though crossed by plicae running from the peripheral spines in an oblique direction.

The central ones, five in number, increase in breadth towards the centre, (one of them nearly double) and are larger than the interstices.

It has a broad, triangular cusp, with one small median denticle and about 6 smaller ones on each side.

The laterals one on each side have a transversely triangular shape, with an unarmed, arched upper and concave proximal and basal margin, with blunt points at the proximal and distal extremities of the basal margin.

The nacreous character of the shell agrees with the Rhipidoglossa, and so does the larger number of uncini.