Verticicosta crassicostata (Melvill, 1912) Huang & Lin, 2020

Huang, Shih-I & Lin, Ming-Hui, 2020, Verticosta n. gen. from Taiwan, Philippine, Gulf of Oman and North Atlantic Ocean (GASTROPODA, CAPULIDAE), Bulletin of Malacology, Taiwan 43, pp. 13-24 : 17

Verticicosta crassicostata (Melvill, 1912) n. comb.

波斯毛螺

(Plate 1, fig. 3)

Trichotropis crassicostata Melvill, 1912 — Descriptions of thirty-three new species of Gastropoda from the Persian Gulf, Gulf of Oman, and North Arabian Sea. Proceedings of the Malacological Society of London 10: 240–254; page 243, plate 12, fig. 5; type locality: gulf of Omen, 24°58’N, 56°54’E, 156 fathoms (= 285 m) depth.

RANGE AND HABITAT

Subtropical Indian Ocean, Gulf of Omen, 24°58’N, 56°54’E, 285 m depth, sand bottom.

COMPARISON AND REMARKS

Shell length 4 mm, small for genus; high-conic and turbiniform with rounded whorl edge. The 1 st teleoconch whorl contains 2 spiral cords and penultimate whorl contains 4 cords and 9 wide and elevated axial ribs. “ …the character of the longitudinal ribs, those of the species now before us being much fewer, more incrassate, and rudely formed… ” in the original description, Melvill (1912) emphasized the differences between V. crassicostata n. comb. and Trichotropis townsendi Melvill & Standen, 1901 having decussated sculpture with axial ribs and spiral cords of equal strength. T. townsendi is not included in Verticicosta n. gen.. V. crassicostata n. comb. is small in profile and bears less axial ribs and spiral cords per whorl than Verticosta campanella n. sp. and Verticosta lanterna n. sp..

Warén & Bouchet (1991) illustrated another 6mm Trichotropis crassicostata from 930 to 980 m depth off Réunion. The whorl is horizontally expanded and edge is angulated; sculpture is composed of 2 adapical infrasutural cords and P1 to P4 derived spiral cords and 17 elevated axial ribs on penultimate whorl. This is an undescribed species in Verticosta n. gen.. There are many other Trichotropis crassicostata by web

research and none of them matches the holotype from Gulf of Omen.