Cerithium citrinum G. B. Sowerby II 1855

Cerithium citrinum Sowerby, 1855

Cerithium citrinum Sowerby, 1855:855–856, pl. 79: fig. 66 [lectotype, herein selected: BMNH, 19861681; 2 paralectotypes 198616823; type locality: Masbate, Philippines]; 1865. pl. 1: fig. 1.—Tryon, 1887:123, pl. 20: figs. 21, 23.—Kobelt, 1893:110–111, pl. 27: figs. 2, 3.—Kira, 1962:27, pl. 13: fig. 21.—Springsteen and Leobrera, 1986:59, pl. 13: fig. 4.

DESCRIPTION.—Shell (Figure 25): Shell tall, turreted, comprising 13–17 inflated whorls and reaching 50 mm length and 19.6 mm width. Protoconch unknown. Early teleoconch whorls purplish blue. Adult teleoconch whorls sculptured with broad, inflated, colabral axial ribs; 8–11 ribs on penultimate whorl. Each whorl with about 13 overriding, thin, spiral threads and deeply incised spiral lines. Numerous microscopic spiral lirae and incised lines overlying larger spirals. Suture deeply incised. Body whorl wide, with weak axial ribs except for varix opposite outer lip of aperture. Base of body whorl excavated by strong siphonal constriction, sculptured with numerous spiral brae. Aperture ovate, about one-fourth the shell length. Columella concave with thick columellar callus and distinct columellar lip. Anterior canal very long, tubular, thin, reflexed and slightly twisted to left of shell axis. Outer lip highly inflated, thickened at edge, strongly crenulated, with many internal denticles and strong tooth at base of outer lip, adjacent to canal. Anal canal well developed, flanked by distinct parietal columellar tooth extending well into aperture. Shell color white-lemon to darker yellow, especially on axial ribs, sometimes with diffuse brown blotches. Anterior canal frequently brown or dark blue, especially at anterior. Aperture usually bright yellow. Measurements (TABLE 14). Periostracum not evident. Operculum corneous, thin, dark tan and with eccentric nucleus.

Radula (Figure 26): Type-1 radular ribbon (Figure 3A) small, about one-twelfth the shell length, comprising about 60 rows of teeth. Rachidian tooth (Figure 26B–D) rectangular-hexagonal with pair of posterior basal ridges and weak, median, posterior projection on basal plate; top of rachidian convex with cutting edge having chisel-shaped central cusp flanked on each side by two pointed denticles. Lateral tooth (Figure 26D) rhomboidal with large central posteriorly projecting buttress and long, posterior, lateral extension on basal plate; cutting edge with large pointed main cusp, one inner flanking denticle and 3 or 4 pointed, outer flanking denticles. Marginal teeth (Figure 26C) with wide shafts and tapering hook-like tips, serrated with slender, pointed denticles. Inner marginal tooth with blade-like central cusp, 3 inner flanking denticles and 3–5 outer flanking denticles. Outer marginal tooth same, but lacking outer flanking denticles.

Anatomy: Body flesh colored, flecked with brown. Snout long; foot long, narrow. Mantle edge lined with small papillae. Inhalant siphon thick, darkly pigmented within. Osphradium greenish brown near mantle edge. Ctenidium narrow, comprised of long triangular filaments. Hypobranchial gland white, with narrow, glandular, transverse ridges. Buccal mass large, jaws large. Type-A pallial oviduct (Figure 4A); anterior seminal receptacle of lateral lamina a very long tube, extending posteriorly to point opposite posterior seminal receptacle of medial lamina.

SYNONYMIC

Cerithium citrinum is a species of sea snail, a marine gastropod mollusk in the family Cerithiidae.