Pleurotoma pentagonalis Reeve, 1845 Ithycythara pentagonalis is a species of sea snail, a marine gastropod mollusc in the family Mangeliidae.

[1] Tucker considers Ithycythara auberiana a synonym of Ithycythara pentagonalis Reeve, L.A., 1845[2] The smooth, ivory white shell has an oblong-ovate shape.

It shows compressed ribs at the angles, pointed at the upper part of the ribs.

This marine species occurs off St Vincent, West Indies.

This Mangeliidae-related article is a stub.