. Shell small (to 13.2 mm), broadly fusiform, truncated anteriorly, stout, body whorl approximately 59% of total length, solid; surface appears waxy, of up to approximately 9 barely convex whorls, with whorl periphery below mid whorl. Sculpture of axial ribs. Protoconch of approximately 1,75 smooth whorls, first partially submerged in second. Axial sculpture of low broad ribs that extend from suture-to-suture, broadest and round-crested below mid-whorl on spire whorls, narrower and ridged on shoulder, relatively few in number, 6-7 on penultimate and 4-6 on last whorl to varix. Spiral sculpture absent except for fine, well-spaced spiral threads on shell base, and distinct ridges on anterior fasciole, strongest anteriorly. Sulcus absent; but axial ribs somewhat reduced and narrowed in the sulcal region. Varix a large cup-handle-like rib behind the anal sinus, producing a lopsided shell profile viewed ventrally. Outer lip thin, projects out a short distance from the varix; some specimens with a strengthening rib near lip edge; stromboid notch weak. Anal sinus deeply notched, U-shaped, positioned on shoulder a little below suture; parietal lobe not constricting the opening. Inner lip emarginated, thick and slightly raised anteriorly, thin in parietal area; and forming a lobe on the parietal wall posteriorly. Anterior canal short, open, unnotched; anterior fasciole not swollen; with approximately 6 spiral ridges. Color solid white, yellowish white or light orange brown; without patterning.

Cerodrillia sanibelensis has all of the key characters of Cerodrillia: an expanded lateral cup-handle-like varix producing an axially lopsided shell; strong ribs that run from suture-to-suture on the spire with little change in the sulcal area; and a waxy smooth shell surface devoid of spiral sculpture, except for lines and ridges on the shell base. Variability. The average length of 14 specimens is 10.36 mm (8.3-13.2 mm), and their average W/L ratio is 0.407. Identification. Cerodrillia sanibelensis is most easily recognized by its rather straight ribs and solid, waxy appearance. It has fewer axials than congeners of similar size. Cerodrillia sanibelensis is most similar to C clappi Bartsch & Rehder, 1939 and C perryae Bartsch & Rehder, 1939. It differs from both in being broader—the varix is more prominent and spire proportionally shorter, and having fewer axial ribs. From C perryae it also differs in having whorls that are less convex; the last whorl with a noticeably less angular shoulder, and in lacking color banding.

W Florida (off Lee Co.; off Collier Co.); Florida Keys (S of Big Pine Key). Reported from 7-13 m.