Crassispira abdera is a species of sea snail, a marine gastropod mollusk in the family Pseudomelatomidae.

It has a dull waxen color with a darker blotch behind the aperture and a dark brown protoconch consisting of a 1+1⁄2 smooth and polished whorls.

The axial sculpture consists of (on the body whorl 7 or 8) ribs which appear at the periphery as conspicuous nodules and become obsolete on the base, except at the intersections mentioned previously.

The outer lip is moderately thickened, sharp-edged, and smooth inside, with a prominent knob behind it.

The inner lip smooth with a rather thick layer of enamel continues down the columella with a raised edge and a chink behind it.