Ptychobela resticula, Li & Kilburn & Li, 2010

Li, Bao Quan, Kilburn, Richard N. & Li, Xin Zheng, 2010, Report on Crassispirinae Morrison, 1966 (Mollusca: Neogastropoda: Turridae) from the China Seas, Journal of Natural History 44 (11 - 12), pp. 699-740 : 734-735

Ptychobela resticula sp. nov.

( Figures 6C, D )

Type material

Holotype. SCS. One specimen. CN S208 B-42, 21°00′ N, 114°30′ E, muddy sand, 83 m, AT, 8 April 1960.

Paratypes. SCS. One specimen , CN N126 B-12, 20°15′ N, 110°45′ E, medium sand, 55 m, AT, 10 February 1960 .

Measurement

See Table 1.

Description

Shell biconic-fusiform, heavy; medium to large (adult length 33.0–41.5 mm). Spire high, approximately equal in length to aperture (including canal); body whorl convex, and anterior canal relatively short, slightly flexed. Teleoconch with 10 evenly convex whorls, body whorl most strongly so. Suture narrow, adpressed, distinct. Sculpture of strong, opisthocline, rounded axial ribs, beginning below sulcus, extending to base of whorl, on last whorl these ribs weaken and evanesce at about midwhorl; with nine ribs on penultimate and last whorls. Subsutural cord very strong, slightly wider than sulcus, bearing three or four fine spiral threads. Spiral ridges strong, rounded, crossing the axial ribs, five to six on penultimate whorl, and 18–19 between the last suture and the tip of the base. Sulcus and interspaces between main ridges with thinner and weaker spiral ridges. Growth lines forming coarse threads. Aperture moderately narrow, outer lip slightly flared, thickened, with low crenulations along its edge and a deep stromboid notch. Anal sinus asymmetrically U-shaped, directed slightly adapically, parietal nodule pronounced. Siphonal canal relatively short and deep, end rounded.

Protoconch high conical, of two to three whorls, smooth; breadth 1.21–1.29 mm. Colour orange-brown, interior of aperture and parietal callus porcellanous-white.

Etymology

Latin resticula , noun, rope-like, referring to the strong subsutural cord.

Distribution

Only known from the type locality, the SCS.

Remarks

Ptychobela resticula sp. nov. is characterised by its proportionally low spire, strong spiral ridges and a rope-like subsutural cord comprising three or four fine spiral threads. The new species is somewhat similar to Ptychobela suturalis ( Gray, 1838) but differs in proportions (such as a lower spire) and a stronger subsutural cord.

Figures

Figure 6. (A) Syntype of Pleurotoma (Drillia) concolor Smith, 1877, BMNH 1964227, Moluccas; 42.1 × 11.2 mm; (B) Ptychobela suturalis (Hainan Island); (C, D) Ptychobela resticula sp. nov. (holotype, SCS, CN S208B-42, 83 m, 41.5 × 14.3 m); (E) Ptychobela vexillium (SCS, CN N31B-13).