Amastra tenuispira

(Original description) The shell is dextral, imperforate, and solid, with an acuminately turreted shape and a conical spire.

Its surface is lustreless, covered with somewhat coarse, irregular incremental striae, while the whorls of the protoconch are very finely radiately sulcated.

The shell consists of 7 somewhat convex whorls, with some specimens showing a slight margining above; the suture is well impressed.

The shell is very thick, with the body whorl being white or pale buff, often with a pinkish tint towards the apex.

Small spots and fragments of a brown outer cuticle are occasionally present on the body whorl.