Assiminea punctum is a species of minute, salt-tolerant snail with an operculum, an aquatic gastropod molluscs, or micromolluscs, in the family Assimineidae.
The length of this species attains 3 mm.
(Original description in Latin) The shell is very minute and scarcely rimose (having a very slight chink). It is ovate-conoidal, very smooth, shining, and horn-green.
The spire is elongated, with a somewhat acute apex. It has five convex whorls, which are joined by a black-margined suture. The body whorl is inflated and does not equal half the length of the shell.
The aperture is acutely oval, with straight margins, and it is brown-edged internally.
This species occurs on Mayotte, Indian Ocean.