Anarithma inornata is a species of sea snail, a marine gastropod mollusk in the family Mitromorphidae.
The shell is more globose and thicker than in Columbella stepheni (synonym of Anarithma metula <small>(Hinds, 1843)</small> )of which it was originally considered a variety. The brown spots are smaller and are better rounded on the upper whorls. On the body whorl, they form a second series located near the base. Notably, the large triangular brown spot does not appear in this species.
This marine species occurs off the Loyalty Islands.