Liotipoma clausa, Mclean, 2012

Mclean, James Hamilton, 2012, New species and genera of colloniids from Indo-Pacific coral reefs, with the definition of a new subfamily Liotipomatinae n. subfam. (Turbinoidea, Colloniidae), Zoosystema 34 (2), pp. 343-376 : 366-368

Liotipoma clausa n. sp.

( Fig. 13 E-H)

TYPE MATERIAL. — Holotype: LACM stn 91-189, Fiji,S side Herald Pass, W side Great Astrolabe Reef , Kandavu Group, 18°46.0’S, 178°27.2’W, 15 m, 20.VI.1991,Twila Bratcher, immature specimen, H 3.0, D 4.2 mm ( LACM 3110 ).

Paratype: same data as holotype, immature specimen, H 2.5, D 3.2 mm ( LACM).

TYPE LOCALITY. — Fiji, S side Herald Pass, W side Great Astrolabe Reef, Kandavu Group.

DISTRIBUTION. — Known only from type material.

ETYMOLOGY. — Latin, clausa , closed, suggested by the massive umbilical plug.

DESCRIPTION

Male shell ( Fig. 13 E-H).

Whorls 3.2 (but mature lip not formed); profile high for genus; with single keel, periphery with strong carination at mid-whorl; shoulder nearly flat-sided, base below keel evenly rounded. Axial sculpture of strong ribs, 33 on last whorl in spire view; weakly spinose and projecting in early whorls, more closely spaced and less spinose in final half whorl. Spiral sculpture of three strong cords on shoulder; base with strong cords, of which three largest become strongly projecting in last half whorl; emergent cord and adjacent subtending cord prominent. Umbilicus fully obstructed by early formation of tongue that precedes formation of expanded final lip; aperture radial, mature lip unknown. H 3.0, D 4.2 mm (immature male holotype).

Female shell

Unknown.

Operculum

Unknown.

REMARKS

The holotype specimen seems sufficiently large and mature to suggest that it reached the stage to commence forming the mature lip. This species is characterised by it high number of axial ribs, short spines, and minor whorl expansion. There are many more axial ribs than in L. solaris n. sp., which also occurs at Fiji. This species, along with L. splendida n. sp. ( Fig. 9 A-D), has 33 axial ribs, the highest count for the genus. This differs from the other species treated here in its massive development of the basal cords. Although lacking the mature lip, mature shells should be readily recognised in the future.

Figures

FIG. 13.— A-D, Liotipoma splendida n. sp.holotype,male shell (MNHN 24772,stn 1269), Doiman Reef,Touhou Sector,New Caledonia, 15-20 m, H 3.2, D 5.1 mm; E-H, Liotipoma clausa n. sp. Holotype, immature male shell (LACM 3110, stn 91-189), Herald Pass, Great Astrolabe Reef, Fiji, 15 m, H 3.0, D 4.2 mm. Scale bars: 1 mm.

FIG. 9. — Liotipoma magna n. sp., female shells: A-D, paratype (MNHN 24768,stn DS105), off NW side Tutuba Island, Espiritu Santo, Vanuatu,92 m,H 3.6, D 5.7 mm;E-G, paratype,off W side Tutuba Island (MNHN 24769,stn DS105),off NW side Tutuba Island,Espiritu Santo, Vanuatu, 92 m, H 3.4, D 5.3 mm. Scale bars: 1 mm.