Rapa sp. cf. R. incurva (Dunker, 1852)

(Figs 11 C-E; 12E)

Bulbus incurvus Dunker, 1852: 126 .

TYPE MATERIAL. — Rapa incurva: Holotype (ZMB 103.967).

TYPE LOCALITY. — Bulbus incurvus: Uncertain: “ China?” [no locality given on label of the holotype].

MATERIAL EXAMINED. — The type material of R. incurva and:

Banc Président Thiers, BENTHAUS, stn DW 1926, 24°38.2’S, 146°00.8’W, 50-90 m, 1 juv dd, 1 juv lv (Figs 11 C-E; 12E).

DISTRIBUTION. — Rapa incurva: Pacific Ocean,from the Kii Peninsula, Japan, “intertidal to 20 m, in base of soft corals” (Higo et al. 1999: 221). From New Caledonia and Loyalty Islands, empty shells in 20 m, alive in 17- 31 m.

REMARKS

Protoconch of 3.7 whorls, 710 µm high and 730 µm wide at the base. Protoconch I of 0.8 whorls covered by pustules. Protoconch II of about 2.9 whorls, with 2 major spiral keels (the abapical starting on the early second protoconch whorl, the adapical starting at the end of the second protoconch whorl), and one minor subsutural keel, sculptured with a series of threads over each keel. Spiral microsculpture evident on the keels.The specimens of the present material, are somehow different from juveniles of Rapa incurva in having a more spherical shape. It is possible, similarly to what happens in Leptoconchus, that also Rapa includes cryptic species of difficult morphological interpretation.