Cerithium interstriatum Sowerby, 1855. (Synonyms: Cerithium fucatum Pease, 1861b; C. clavis Sowerby, 1865; Cerithium thaanumi Pilsbry and Vanatta, 1905.) Length, 12 mm; diameter, 4 mm. Shell: conic-elongate, inflated; with beaded spiral threads; cream occasionally splashed with dark brown. Spire: protoconch of three brown whorls, the apical smooth and mamillate, the others with two spiral keels, the apical keel smooth, the abapical beaded; teleoconch of five to ten convex whorls; suture shallow, oblique on the apical whorls. Sculpture: somewhat variable — apical whorls clathrate, later whorls usually with about three spirals of elongate beads on each whorl, the interspaces twice the diameter of the spirals and often with smooth threads between; suture bordered by a thread. Aperture: subovate; outer lip thin; base concave, encircled by a beaded spiral; siphonal canal short. Color: fawn splashed with brown. These cerithids are common on fringing reefs. C. interstriatum has also been recorded from the Red Sea (Jousseaume, 1931).