Alcadia pusilla is a species of an operculate land snail, terrestrial gastropod mollusk in the family Helicinidae.
(Original description) The shell has a depressed globular shape. It has a horn color that can appear brownish. It features extremely fine growth striae and a subacute apex. The spire is moderately elevated with curvilinear outlines. The shell has more than four slightly convex whorls with a distinct suture. The aperture is rather large, well-rounded on the right side, and somewhat sinuate on the left side. 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. This species is much less discoidal than Alcadia macilenta (C. B. Adams, 1849).[1]
This species occurs in Jamaica.