Conus rattus Hwass, 1792

Franklin, J. Benjamin, Subramanian, K. A., Fernando, S. Antony & Krishnan, K. S., 2009, 2250, Zootaxa 2250, pp. 1-63 : 44

48. Conus rattus Hwass in Bruguière, 1792 (Figure 49)

Conus rattus Hwass in Bruguière, 1792: 700, no. 89 (representation of lectotype, Cuvier 1798: pl. 338, fig. 7 (45 x 29 mm) (Kohn 1968); "les mers d’Amérique").

Conus taitensis Hwass in Bruguière, 1792: 713, no. 108 (representation of lectotype, Cuvier 1798: pl. 336, fig. 9 (36 x 23 mm) ( Röckel et al. 1995); "Isle d’ Otaiti, dans 1’ Océan pacifique").

Conus chemnitzii Dillwyn, 1817: 363 , no. 108 (representation of holotype, Chemnitz 1795: pl. 182, figs. 1764, 1765) (37 x 23 mm) ( Röckel et al. 1995); " Ceylon ").

Conus taheitensis Reeve, 1843 : pl. 15, sp. 78.

Conus viridis Sowerby II, 1857: 20 , pl. 5, fig. 102 (representation of lectotype, Sowerby II 1857: pl. 5, fig. 102 (22 x 12.5 mm) ( Röckel et al. 1995); "Hurghada, Egypte, Rode Zee ").

Conus semivelatus Sowerby III, 1882: 118 , pl. 5, fig. 3 (holotype, NMWC (18 x 11.5 mm) ( Röckel et al. 1995); " Red Sea ").

Conus tahitiensis Dautzenberg, 1933: 89 ("Islands of Taheita, Annaa").

Material examined: MBMCS148 , 9 specimens, SL 28–56 mm; SW 13–25 mm .

Description. Shell small to moderately large, solid, glossy. Body whorl conical to broadly conical; outline variably convex at adapical third to three fourth, left side concave below. Shoulder angulate. Spire of low to moderate height, outline slightly convex. Body whorl with variably prominent fine spiral ribs at base, becoming obsolete adapically. Aperture narrow, outer lip thin.

Ground colour bluish-white. Body whorl overlaid with various shades of brown leaving a broad interrupted spiral ground-colour band below shoulder and another obsolete to broad band at centre. Solid dark brown spiral lines may extend from base to just below the shoulder; on some portions of the body whorl, brown spiral lines articulate with white dots to produce a speckled appearance. Base violet. Aperture violet. Periostracum yellowish brown, slightly opaque and transversely finely ridged.

Distribution. In India, the first record of C. rattus was based on a live specimen collected by Winckworth at Krusadai Island ( Kohn 1978).

The specimens described herein were collected from Keelakarai ( Table 6) by trawling in 10–40 m and diving in 5–8 m, in and around the sub-tidal coral reef flats and from Pamban by trawling in 10–40 m ( Table 6).

Remarks. This is the second record from India. Live specimens obtained by diving near subtidal coral reefs suggest its preference for this habitat. The distribution of C. rattus is probably limited to the Gulf of Mannar.