Cellana karachiensis Winckworth, 1930

Vakani, Bhavik, Nakano, Tomoyuki & Kundu, Rahul, 2020, Diversity and taxonomy of the intertidal patellogastropod limpets of the mainland Indian coastline, Zootaxa 4728 (2), pp. 211-226 : 214-215

Cellana karachiensis Winckworth, 1930

( Fig. 2 , Fig. 9a )

Description. Oval and cone-shaped shell, slope of the apex curves gently to the anterior and posterior. Shell surfaces usually with radiating spotted bands, but the banding pattern changes with age. Normally, the shell has eleven bands on dorsal surface, but some may be indistinct or disappear due to erosion. Size of shell up to 50 to 60 mm in length. Shell slightly broader to the posterior as compared to the anterior, moderately elevated. Apex anterior, subcentric. Margin slightly contoured. Sculpture of dense, crisp, radial riblets varying from 60 to 90; in juvenile animals, 55 to 60. Shell thickness approximates about 1 to 1.5 mm, varying with age. Colour of shell pale brownish buff exteriorly, with 11 radiate bands (spatula) of deep/dark reddish to brown on shell, internal spatula chestnut-brown; sometimes only chestnut colored dashes on whole shell, sometime a mix. Foot colour and tentacles are mostly found creamy white in colour. Mantle skirt might contain series of small tentacles.

Radular morphology ( Fig. 9a ). Radula docoglossan, formula: 1 + D1 + 1 + D1 +1. Radula long, about four to five times of length of animal. Rachidian tooth very small and spear-shaped. One lateral tooth on each side of rachidian tooth, having shape of bifurcated canine tooth. Bifurcation of tooth uneven, one cusp being a little longer than the other. One marginal tooth on each side, which looks similar to the lateral. In both, marginal and lateral teeth, the bigger cusp of each tooth points towards the inner side of radular ribbon.

Materials examined. Specimens were collected from Veraval coast, Gujarat, India (20°54’38.1”N 70°21’04.1”E). Five specimens (length 29.5–31.5 ± 0.73 mm, width 25.6–27.9 ± 0.87 mm and height 8.8–15 ± 2.31 mm) were ex- amined. Three specimen having Museum ID: ZMGDNC5.1, ZMGDNC5.2, ZMGDNC5.3, coll. Bhavik Vakani, are deposited in the Museum.

Remarks. Earlier references for this species indicated that it was endemic to the Gulf of Oman, extended to the Karachi coast and up to the Gulf of Kutch ( Powell 1973). However, Vakani et al. (2014), Joseph et al. (2016a), Poriya et al. (2016) also recorded this species from the south Saurashtra coastline at Veraval, India. The rocky shoreline of the south Saurashtra coastline of the Kathiawar Peninsula seems to be the ideal habitat for this species.

Habitat. Exclusively found on the spray to upper littoral zone in the rocky intertidal area.

Distribution. Gulf of Oman, Karachi coast, Pakistan and up to the south Saurashtra coastline (Gujarat, India). This species was not observed from any other parts of the mainland Indian coastline during the study period.

Figures

FIGURE 2. Cellana karachiensis. a (dorsal), b (ventral), c (ventral empty shell), d (lateral). a–d (ZMGDNC1.2a), e–j variants of Cellana karachiensis—e (ZMGDNC5.1), f (ZMGDNC5.2), g (ZMGDNC5.2g), h (ZMGDNC5.3), i (ZMGDNC13.2i), j (ZMGDNC5.2j).

FIGURE 9. Radular teeth of patellogastropods (x 50). a: Cellana karachiensis, b: Cellana radiata, c: Cellana rota, d: Cellana conciliata, e: Cellana cylindrica, f: Patelloida lentiginosa, g: Lottia sp. (0.5 mm).