Mareleptopoma drivasi, Renard & Bouchet, 2003

Renard, Jacques Le & Bouchet, Philippe, 2003, New species and genera of the family Pickworthiidae (Mollusca, Caenogastropoda), Zoosystema 25 (4), pp. 569-591 : 575-577

Mareleptopoma drivasi n. sp.

( Fig. 4 )

“ Mareleptopoma drivasi ” – Bouchet 1987: figs 86, 87 (nomen nudum).

TYPE MATERIAL. — Holotype (dd) and 4 paratypes (dd) in MNHN.

TYPE LOCALITY. — Cap La Houssaye, La Réunion, 12 m.

ETYMOLOGY. — The specific epithet honours Jean Drivas, one time resident of La Réunion and enthusiastic collector of Indo-Pacific micromolluscs.

MATERIAL EXAMINED. — A total of 13 specimens (10 lots).

La Réunion. Cap La Houssaye , 12 m, 1984, leg. Drivas, 1 dd, holotype ( MNHN; Fig. 4A, B, C ). — Boucan Canot, 57 m, 1984, leg. Drivas, 4 dd, paratypes ( MNHN; Fig. 4D ). — Boucan Canot, 45- 50 m, coll. Palazzi, 1 dd .

Japan. Najikin, Motobu Peninsula, Okinawa, 26°42’N, 127°56’E, 35 m, 1978, leg. Bolland, 1 dd ( LACM 78-22.4). — 1 km WNW Onna Village, Okinawa, 26°30’N, 127°51’E, 55 m, 1978, leg. Bolland, 1 dd ( LACM 78-26.3).

Palau. Helen I., fore reef, in crevice, 1994, leg. Myers, 1 dd ( MNHN ex Paulay). — Tobi I., fore reef, in crevice, 17 m, 1994, leg. Myers, 1 dd ( MNHN ex Paulay).

Guam. Apra Harbour, IM shoal, south side, in underhung area, c. 1-1.5 m into reef, depth 5-7 m, 1994, leg. Paulay, 1 dd ( MNHN).

Mariana. Saipan, roof of “Grotto”, 5-10 m, 1994, leg. Paulay, 1 dd ( MNHN).

Indonesia. Pulau Run, Banda Archipelago, 21 m, 1994, leg. Birkeland, 1 dd ( MNHN ex Paulay).

DISTRIBUTION. — Indian Ocean: La Réunion; Pacific Ocean: Okinawa, Guam, Marianas, Indonesia.

DESCRIPTION

Holotype ( Fig. 4A, B, C ). Shell very small, rissoiform, consisting of five whorls. Protoconch ( Fig. 4C ) consisting of 1.5 smooth globular whorls, indicating non-planktotrophic larval development. Teleoconch sculpture consisting of two spiral cords, one below suture, another at mid-whorl. Third spiral cord present as a sutural thread, hidden by deep suture. Axial sculpture consisting of faint straight equidistant ribs, slightly oblique; nine such ribs on first teleoconch whorls, 22 on body whorl. Intersections of axial and spiral sculpture forming prominent narrow tubercles. Base convex, sculptured, in addition to three nodulose spiral cords, with faint smooth cord in middle of base, plus a strong cord surrounding umbilicus. Umbilicus open. Aperture rounded; peristome thickened, more so in outer than inner part. Successive positions of peristome seen concentrically on outer lip; six such rings gradually narrow aperture of holotype.

Dimensions

H = 1.1 mm, D = 0.78 mm.

REMARKS

The sculpture of Mareleptopoma drivasi n. sp. resembles that of M. iredalei ; however, the body whorl of M. drivasi n. sp. is larger and forms 45% of the total shell height (vs 35% in M. iredalei ). The peristome of M. drivasi n. sp. is much broad- er, and its larval shell is of non-planktotrophic type.

Figures

FIG. 4. — Mareleptopoma drivasi n. sp.; A-C, holotype, cap La Houssaye, La Réunion (MNHN), H = 1.1 mm; A, B, apertural and side views; C, protoconch; D, paratype, Boucan Canot, La Réunion (MNHN), H = 0.93 mm. Scale bar: C, 100 µm.