Turris amicta ( E. A. Smith, 1877 )

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 : 7-8

Turris amicta ( E. A. Smith, 1877)

Plate 3 , figs A–D

Pleurotoma amicta E. A. Smith, 1877: 488 . Type loc.: “Sandwich Islands” [erroneous, emended to Bombay, N. W. India, by Powell (1966)].

Surcula cingulifera var. amicta ; Melvill 1917: 162.

Turris amicta ; Powell 1964: 334, pl. 254, figs 7–8.

Turris (Annulaturris) amicta ; Powell 1966: text-fig. C42 (radula), pl. 6, fig. 18.

DESCRIPTION: Shell fusiform with acuminate, orthoconoid spire but with relatively short base, b/l 0.30–0.36, a/l 0.37–0.42;, siphonal canal short, slightly flexed to right; inner lip sigmoid, thickly calloused, in gerontic individuals developing a wide fasciole with a large false umbilicus; whorls rather flat-sided, suture deep, sometimes channelled. Outer lip convex in side view, anal sinus rather shallow, narrowly V-shaped.

Sculpture of rather uniform spiral cords; subsutural cord not projecting, bearing 2–3 spiral threads. Sulcus very narrow and moderately deep, often slightly recessed under sinus cord. Sinus cord bearing 1–2 ridges (flattening out towards lip). Basal part of spire whorls with 3–4 main cords, slightly angular with widely sloping sides, to rounded, the upper one forming the barely projecting periphery; often a weaker ridge in intervals. Base of last whorl with about 10–14 main cords, intervals between cords with 1–3 intermediary threads, rostrum with an additional 10–12 fine, close threads. Collabral threads relatively strong in interstices, periostracum sometimes giving them a lamellar appearance.

Uniform white, with a persistent yellowish-olive periostracum.

Protoconch unknown.

Maximum length 65 mm.

DISTRIBUTION: Gulf of Aden and Pakistan, south to India and Sri Lanka ( Powell, 1964), north to Chennai, shallowly subtidal in marine grassflats.

TYPES: Three syntypes NHMUK 1872.10.21.20 and 1964.2.29 .

OTHER MATERIAL EXAMINED: INDIA: off Koswari Is, Tuticorin area, in 2–3 m ( NMSA L5413, L8000: RK); Bombay ( ANSP 292066: Townsend; A. W. B. Powell); Cuffparade, Colaba, Bombay ( ANSP 317212: F. B. Steiner). PAKISTAN: Karachi ( ANSP 99310)

REMARKS: An uncommon species in modern collections, but is probably overlooked in the field, perhaps on account of its drab appearance. It is most similar to Turris kathiewayae n. sp. in shell characters; that species, however, lacks the persistent periostracum, and has a longer, straighter siphonal canal and steep-sided spiral cords. Bombay specimens appear to be much smaller (e.g. 38.5 mm) than those from the east coast of India.

Figures

PLATE 3. Turris amicta (E. A. Smith, 1877): A, B—Syntype of Pleurotoma amicta, H. Cuming “Sandwich Islands”, NHMUK 1964229, 49.5 x 16.1 mm; C, D—off Koswari, Is., S-E India, 2–3 m, NMSA L5413, RK, 62.6 x 18.1 mm.