Shell broadly conic, yellowish white, with the tip horn-colored and the spiral cords of the postnuclear whorls pale chestnut-brown, fading as they cross the ribs. On the base the spiral cords are interrupted by the much more numerous ribs, which gives them a catenated effect. The tip of the base is brown for about one fifth of its length, but an area of equal width posterior to this lacks the brown interrupted bands. The interior of the aperture is bluish white. Nuclear whorls three, the first well rounded, the other two marked by a strong acute spiral keel a little anterior to the middle of the whorls. Postnuclear whorls well rounded, marked by exceedingly strong, broad, almost humplike axial ribs, which become very attenuated in the posterior sinal region and evanesce at the suture. Of these ribs, IO occur upon all but the last whorl, which has 12. The intercostal spaces are a little wider than the ribs. At the summit of the whorls in the posterior sinal region the shell is marked by rather strong, closely spaced, curved riblets, which give to this part a crenulated aspect. On the base additional riblets are intercalated so that one, two, or even three slender axial ribs may appear between the heavy knobs described above. These are of very regular strength and spacing and are rendered nodulose by the spiral threads. The yellowish white nodules furnish a decided contrast to the dark areas that separate them. The spiral sculpture of the postnuclear whorls consists of three exceedingly feeble threads in the sinal region at the summit on the first two turns. On the third turn an additional thread is added and on the remaining turns, two more. The posterior of these threads render the later whorls finely nodulose. Anterior to the sinal groove three spiral threads are present on the first and second of the postnuclear whorls, and five on the remaining whorls except the last, which has six. Here too an additional slender spiral thread is present between the first and second and the second and third of the strong threads. The suture is given a somewhat false aspect by the appressing of the summit of the whorls against the preceding turn. Periphery well rounded. Base moderately long, marked by the slender axial riblets described above, which become evanescent a little anterior to the middle, and 21 spiral threads, which are of almost equal strength and spacing, the last three near the tip of the columella, however, being less strong and a little more closely spaced. The entire surface of the shell is covered with fine granules. Aperture moderately large and rather broad, strongly channeled anteriorly and posteriorly. Outer lip reinforced by a strong varix, from which the edge of the lip projects as a clawlike element that is bent inward. The callus on the inside of the lip marking the varix is finely denticulated. Fine denticles also mark the somewhat sinuous columellar margin of the aperture.

This species is related to Glyphostoma gabbii, from which it differs markedly in its color pattern and detailed sculpture.

Caribic. Puerto Rico.