Diniatys dentifer (Adams, 1850)

Bulla dentifera Adams, 1850: 588, pl. 115, fig. 124.

Atys dentifera — Sowerby 1870: pl. 3, sp. 13. Schepman 1913: 470.

Atys (Dinia) dentifer — Martens 1880: 303.

Atys (Dinia) dentifera —H. & A. Adams 1854: 21. Watson 1886: 641. Pilsbry 1895: 276, pl. 27, fig. 81. Kobelt 1896: 27, pl. 8, fig. 15.

Diniatys dentifer — Iredale 1936: 329. Habe 1952: 141, pl. 20, fig. 12. Gosliner et al. 2008: 28.

Type locality. Marutea Atoll, French Polynesia (Lord Hood’s Island).

Material examined. the Philippines, 1 shell examined, MNHN, Paris (B17/ OT 793), H = 3.5 mm; Mariana Islands, Guam, 5 spcs dissected, UF 374130, H = 3.1–4.6 mm; Maui, Hawaii, 1 spc. dissected, ZMBN 81706, H = 4 mm; the Philippines, 1 spc. dissected, MNHN, Paris (B17/ OT 793), H = 3.8 mm.

Animal (Fig. 1H): Whitish and greenish pigmentation abundant all over body; dark blotches present on mantle; eyes visible.

Shell (Figs 3B, 14A, B): Maximum height 12 mm; whitish; fragile, translucent, ovoid, narrower towards both ends, posterior part broader than anterior part, anterior end protruded, posterior end truncated; spire sunken, columella ends in tooth-like projection; spiral grooves at both ends only (anterior = 12–13, posterior = 15), inconspicuous axial lines present throughout shell.

Jaws (Figs 14C, D): Present, crescent shape, jaw rodlets with 9–11 denticles.

Radula (Figs 14E, F): Radular formula at mid-point 16–22 x 6.1.6; median tooth with broad base, sharp triangular central cusp, small triangular lateral cusp; outer lateral teeth hook-shaped, broad base with semi-circular projection outwardly, size decreases outwardly.

Gizzard plates (Figs 15A, B): Three gizzard plates; broad, almost equal size from anterior to posterior, 11–13 ridges, rachis conspicuous, single rows of rods with pointed tips along top edge of ridges, anterior side of ridges and top side of rachis covered by tiny rods with pointed tips, posterior side of ridges smooth, density of rods increases posteriorly.

Male reproductive system (Fig. 15C): Total length 4.6 mm (H = 3.5 mm). Formed by three parts: prostate, seminal duct and penial region; prostate elongated, bilobed, proximal lobe larger, semi-translucent, distal lobe opaque-yellowish; long and thin seminal duct connects prostate and penial region, anterior part of seminal duct narrower and translucent, coils into a loop before inserting penial region; penial region elongated, semi-translucent, about half of length of seminal duct, a narrower duct is observed within.

Ecology. Associated with cyanobacteria, particularly Lyngbya, on rock reef flats and beds of Halimeda spp. at the depth of up to 21 m (Gosliner et al. 2008; present study).

Geographical distribution. Madagascar, the Philippines, Japan, Indonesia, Papua New Guinea, Guam, Hawaii, French Polynesia (Watson 1886; Kay 1979; Gosliner et al. 2008; present study).