Turridrupa polynesia Stahlschmidt, Puillandre, Olivera & Kantor sp. nov.

(Figs. 12 K–O, 23 D)

Turridrupa sp. 2 Boutet et al. 2020: 457, unnumbered fig.

Type material:

HOLOTYPE: French Polynesia, Society Island, Moorea, -17.5145°, -149.7616°, 30–33 m, outer reef slope, rubble, coll. by C. Meyer et al., 14.7 mm (UF 428006, Figs. 12 K–M).

PARATYPE 1: French Polynesia, Tahiti, shallow water (PS-616, Fig. 12 N) .

PARATYPE 2: French Polynesia, Society Island, Moorea, Temae Bay, -17.4915°, -149.7517°, 7–20 m (UF436452, Fig. 12 O) .

Sequenced material

Holotype (UF 428006).

Material examined

FRENCH POLYNESIA: Society Islands, Tahiti, 2 spms (Gori collection)—Tuamotu Archipelago, Takaroa, 2 spms (Gori and Chino collections).

Distribution

Presently known from the Society Islands and the Tuamotu Archipelago, “shallow water” to 33 m.

Description

Shell medium-sized for genus, up to 17.6 mm in height, clavi- to fusiform, solid; spire more than 1.5 times height of aperture including siphonal canal; suture narrow and inconspicuous, siphonal canal, moderately long; anal sinus shallow, U-shaped, expanding on the opening, its apex on the weak second spiral cord; inner lip with thick callus, forming a pad adjacent to end of aperture, stromboid notch very short and shallow.

Sculpture of smooth, strong spiral cords which are slightly narrower than their intervals, each whorl with 3–4 evenly-spaced spiral cords (the 4 th usually hidden by succeeding whorls); more or less equally strong, smooth expect the sinus spiral cord with laterally elliptical and low gemmules, about 25 on the penultimate whorl. Last whorl with about 10 strong spiral cords, more closely-spaced and weakening anteriorly; interspaces between spiral cords with weak, microscopic spiral threads (mainly on the base) and axial plicae.

Protoconch domed, eroded in all examined specimens, of approximately 3 whorls, last two with arcuate axial riblets.

Colour uniform beige-yellowish to light to dark brown.

Colour uniform light yellowish brown with paler apex (protoconch and first 3 spiral whorls).

Radula (Fig. 23 D) ~44 rows of teeth, including 6 nascent rows; length ~1.4 mm. Central formation resembles an integral tooth with indistinct anterior margin, slightly elevated bow-shaped posterior margin, and sharp, short, curved central cusp (length/width ~4). Marginal teeth ~100 µm long (1.4% AL). Major limb broad. Accessory limb very narrow anteriorly, fuses with dorsal side of major limb, no socket. Broadens gradually toward outer margin, width ~half that of major limb. Length ~0.6 of major limb, nearly reaches outer limit of major limb.

Remarks

Turridrupa polynesia sp. nov. stands nearest to Turridrupa cincta in general appearance but is easily distinguished from that species by the more fusiform shell due to its longer siphonal canal and by the different spiral sculpture. While the sinus spiral cord of T. cincta is very weak and bears rarely any knobs, it is strong and has well developed gemmules in T. polynesia sp. nov. Molecular data clearly indicate that T. polynesia is not closely related to T. cincta .

Ethymology

Named after the area where the species is known from (Polynesia).