Indian Journal of Geo-Marine Sciences Vol. 43(10), October 2014, pp. 1942-1944

Occurrence of a rare lamellarid, Coriocella hibyae (Wellens, 1991) from Andaman Islands

*CH. Ramesh, R. Mohanraj, K. N. Murthy, P. Karthick & S. Narayana Department of Ocean Studies and Marine Biology, Pondicherry Central University, Port Blair-744102, Andaman & Nicobar Islands, India. [E-mail address: [email protected]]

Received 14 October 2013 ; revised 9 December 2013

In the present study the occurrence of a rare lamellibranch Coriocella hibyae from Andaman Islands is being reported. Three samples of C. hibyae were found in an undisturbed shallow water coral reef region in Burmanallah and the biology of this species is described and identified based on their internal shell and radula structures as C. hibyae which has been first described by Wellens (1991) from the Republic of Maldives.

[Key words: Coriocella hibyae, Andaman]

Introduction by of Wellens (1991). X-ray photographs The Coriocella is classified under the were taken for observing the structure of the Phylum , family shell. Specimen was dissected, shell, radula consisting of 6 species that have been and sex organs were removed and observed registered in WoRMS. Among these under light microscope (Olympus BX41). Coriocella hibyae was first reported from the Specimen was registered with National Republic of Maldives2 and also found to be Zoological Collection of ZSI, Port Blair and distributed in Indonesia, Philippines and the registration number assigned was 8493. Myanmar3. This species is a carnivore found in coral reef and rocky environments. Their body surface is smooth, colour varies from shiny bluish green to pale pink colour with smooth sponge like tissue that covers the internal shell. In the present study we report the biology of this species, whereas earlier reports by Venkataraman et al (2012) showed their presence in these waters.

Materials and Methods Sampling was done during low tide at Burmanallah coast, Port Blair Lat’ ⁰ ⁰ 11 35’35.94” N; Long’ 92 44’28.22” E from Figure 1. Map showing study region, Burmanallah( ). an undisturbed shallow water coral reef area enclosed by mangroves (Fig. 1). Three Results specimens were found in undisturbed shallow Coriocella hibyae (Wellens, 1991) water at a depth of 1 m with the presence of Taxonomic position: few corals of Porites sp. Two specimens Phylum : Mollusca Cuvier, 1795 were collected and the other was left as such Class : Cuvier, 1795 because of their uncommon presence. Order : Golikov & Samples were transferred into sterile zip lock Starobogatov, 1975 bags and were brought to the laboratory and Family : Velutinidae (Lamellariidae) preserved in Ethyl alcohol for further studies. Gray, 1840 These specimens were identified as described Genus : Coriocella Blainville, 1824 RAMESH et al.: OCCURRENCE OF A RARE LAMELLARID, CORIOCELLA HIBYAE 1943

Species : hibyae (Wellens, 1991) 8 & 9). The shell is white in colour, very thin Common Name: Maldives Sponge Snail and has growth curves on it (Fig. 7). Shell has 3 whorls with the incompletion of the third Description: The specimens were identified whorl (Fig. 5 & 6). Light microscopic studies as Coriocella hibyae based on external and of radula showed that it is taenioglossate internal morphological characteristics. The radula about 2 cm long with 67 small rows of size of the specimen is about 4.5 cm long, 2.5 teeth (Fig. 10 - 12). The taenioglossate radula cm broad and body possesses a central formula is I.I.I. Canine tooth was observed on bulbous boss surrounded with four other both right and left teeth (Fig. 13). Lateral bosses. Surface colour of the body is shiny view of radula structure was also observed bluish green with numerous small dark brown under the microscope (Fig. 14). The specimen spots and ventral body surface is dark pink in was identified as male by dissecting out the colour (Fig. 2- 4). X-ray photographs revealed penis (Fig. 15). . the presence of a shell in this (Figures.

Figures. 2,3 & 4. Dorsal, lateral and ventral view photographs of Coriocella hibyae. Fig. 5 & 6. Dorsal view of the internal Shell. Fig. 7. Ventral view of the internal Shell. Fig. 8 & 9. X-ray photographs of dorsal and ventral views of the internal shell. Fig. 10, 11 & 12. Taenioglossate radula (4X&10X). Fig. 13. Canine teeth on right rachidian. Fig. 14. Lateral view of radula. Fig. 15. Penis of C. hibyae. Pondicherry University. The first author Remarks: Coriocella hibyae was first thanks the Department of Science and described by Wellens (1991) from the Technology for the INSPIRE fellowship. Republic of the Maldives and it has been References noted as an endemic species to Maldives5. But 1. WoRMS., World register of marine this species was found to extend its species (WoRMS). distribution in Indonesia, Philippines, http://www.marinespecies.eu, (2013) Myanmar (www.nudipixel.com) and Accessed on 18-04-2013. Andamans4, which shows that this species is 2. Wellens, W., Coriocella hibyae sp. nov: a not an endemic species. The present study new Lamellaria species (Gastropoda: pertains to the biology of this species which Prosobranchia) from the Republic of has not been reported from these waters. Maldives, J. Conchol., 34(1991) 73-80. 3. NUDI PIXEL., www.nudipixel.com, Acknowledgement (2013) Accessed on 09-04-2013. Authors thank Caren Topley of the Conchological Society of Great Britain and Ireland, Mr. Sreeraj of Zoological Survey of India, Port Blair, and the authorities of 1 944 INDIAN J. MAR. SCI., VOL. 43, NO. 10 OCTOBER 2014

4. Venkataraman K, Raghunathan C, Raghuraman R, & Sreeraj C R, Marine biodiversity, (Published by the Director, Zool. Surv. India., Kolkata) 2012, pp. 164. 5. Apte D., Field guide to the marine life of India, (Published by Deepak Apte, Poorva Society., Thane) 2012, pp. 502.