Alcadia pusilla is a species of an operculate land snail, terrestrial gastropod mollusk in the family Helicinidae.

[1] The shell of adult snails has a depressed globular shape.

It features extremely fine growth striae and a subacute apex.

The shell has more than four slightly convex whorls with a distinct suture.

The outer lip is thin, moderately dilated, and well-reflected, with a deep curved incision similar to that of Alcadia brownii palliata (C. B. Adams, 1849), located just below the columella, whose end is sickle-shaped.