Tropidoturris planilirata is a species of sea snail, a marine gastropod mollusk in the family Borsoniidae.

[1] The size of the biconic shell attains 16.8 mm.

Characteristical for this species is the fact that the shell has no axial ribs.

The broad spiral lirae are close and flattened.

[2] This marine species occurs off KwaZulu-Natal, South Africa .