Turris clausifossata, Kilburn & Fedosov & Olivera, 2012

Kilburn, Richard N., Fedosov, Alexander E. & Olivera, Baldomero M., 2012, Revision of the genus Turris Batsch, 1789 (Gastropoda: Conoidea: Turridae) with the description of six new species, Zootaxa 3244 (1), pp. 1-58 : 16-17

Turris clausifossata sp. nov.

Plate 8 , figs A–E

? Turris undosa (non Lamarck, 1816); Wilson 1994: 194, pl. 38, fig. 15.

DESCRIPTION: Shell thick, fusiform, base somewhat contracted, b/l ca 0.35, a/l 0.38, whorls gently and evenly convex, suture shallow, but sharply incised; siphonal canal rather straight, short, about half rest of aperture, columella callus fairly thick, with a slight parietal nodule, fasciole weak, with a narrow false umbilicus. Outer lip opisthoclinely convex, drawn in at base of siphonal canal, edge crenate, stromboid notch distinct; anal sinus moderately shallow, linguiform, with a raised border.

Spiral cords low but angular, their crests slightly posteriorv to median. Early whorls with three subequal spiral cords, from about the 11th whorl, the subsutural one separating as the subsutural cord. Subsutural cord declivously angular with two spiral ridges, the posterior the weaker; sulcus very shallow, narrower than subsutural cord, anal cord very narrow, rather tabulate, shallowly bifid, flanked by converging, oblique lamellae; base of whorl with 3 spiral cords, median one weak, peripheral one the strongest; these cords equal to their intervals or narrower. Upper part of base with 4 main spiral cords, with some weaker intermediaries; rostrum with about 12 fine, well-spaced spiral threads. Collabral threads distinct, interstitial.

Colour dull, pale brown, spiral cords with rounded reddish-brown spots, obliguely aligned on later whorls, forming continuous stripes on early ones’ aperture and columella callus white.

Protoconch somewhat mamillate, of about 2 whorls, 2nd whorl with dense, arcuate riblets, width 0.79 mm

DISTRIBUTION: Known only from the type locality, on the coast of western India.

TYPE LOCALITY: 3 miles South of Dwarka, Gujarat, INDIA

TYPES: Holotype (Fig. 8 A, B),, 3 mi. S. of Dwarka , Gujarat, INDIA, Anton Brun Stn 216A, 21°49’N, 68°55’E, 27.5–28.5 fath. [50–52 m], 58.1 x 20.2 mm, MCZ N362501 . Paratype 1, juvenile 58.1 x 20.2 mm, same data; Paratype 2, juvenile 49.5 x 15.3 mm, same data .

REMARKS: Although only one adult and two juveniles are known, they are sufficient to demonstrate the uniqueness of the species. Although superficially similar to Turris nadaensis , the spiral furrows between the cords are much shallower than in this or any other species, the anal cord being scarcely higher than the adjacent surface. Turris tanyspira is perhaps the most similar species to clausifossata , but the latter differs in the much wider and shallower intercostal furrow anterior to the anal cord, which is furthermore narrower, lower and non-shouldered, and is crossed by stronger growth-plicules.

ETYMOLOGY: clausus (filled) + fossata (grooves), Latin, alluding to the apparently “filled-in” spiral grooves.

Figures

PLATE 8. Turris clausifossata nsp.: 3 mi. S. of Dwarka, Gujarat, India, Anton Brun Stn 216A, 50–52 m, Cambridge University N362501: A, B—holotype, 58.1 x 20.2 mm; C –juvenile paratype, 52.2 x 17.0 mm; D, E—juvenile paratype, 49.5 x 15.3 mm.