Gaza superba

The shell is 2,5 to 4 cm. in width and present a somewhat elevated spire. The apex is open in adult stage. The umbilicus is about 75% covered by callus. The color of the shell is old ivory golden sheen. The early whorls are faintly wine colored. The operculum is circular and shows yellow to brown colors (Original description W.H. Dall) Shell in general features recalling Gaza daedala, much of whose description would apply with little change to this species. The eight whorls are in the adult roundly shouldered below the suture, rounded at the periphery, somewhat flattened on the base, and deeply and widely umbilicated. The umbilicus is a little more than half covered by a nacreous callus. The first 2½ whorls are transparent, not nacreous, very obtuse with the nucleus not prominent. The next 3½ whorls are smooth, except for faintest lines of growth, glassy with the nacre shining through. The remainder of the shell is covered with delicate and distinct lines of growth, sometimes a little more pronounced near the suture, and by revolving lines almost too shallow to be called grooves. These are most prominent on the periphery, evanescent on the flattened part of the base and above near the suture. On the body whorl these are about 0.5 mm. apart. The region near the suture is almost smooth. The suture is very distinct, but not channelled. …