Inkinga platystoma is a species of sea snail, a marine gastropod mollusk in the family Horaiclavidae.

The two apical whorls are remarkably large.

It equals about 5/13 of the total length of the shell.

The sinus is large and moderately deep.

[2] This species occurs in the demersal zone off the Cape of Good Hope to Eastern Transkei, South Africa.