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

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

*CH. Ramesh, Raju. Mohanraj, Kada. Narayana Murthy, Perumal. Karthick & Sumantha. Narayana

Department of Ocean Studies and Marine Biology, Pondicherry Central University, Port Blair-744102, Andaman & Nicobar Islands, India. [E-mail address: [email protected]]

Received ; revised

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 These specimens were identified as described The Coriocella is classified under the by of Wellens (1991). X-ray photographs Phylum , family were taken for observing the structure of the consisting of 6 species that have been shell. Specimen was dissected, shell, radula registered in WoRMS. Among these and sex organs were removed and observed Coriocella hibyae was first reported from the under light microscope (Olympus BX41). Republic of Maldives2 and also found to be Specimen was registered with National distributed in Indonesia, Philippines and Zoological Collection of ZSI, Port Blair and Myanmar3. This species is a carnivore found the registration number assigned was 8493. 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’ 11⁰35’35.94” N; Long’ 92⁰44’28.22” E from

an undisturbed shallow water coral reef area Figure 1. Map showing study region, Burmanallah( ). enclosed by mangroves (Fig. 1). Three specimens were found in undisturbed shallow Results water at a depth of 1 m with the presence of Coriocella hibyae (Wellens, 1991) few corals of Porites sp. Two specimens Taxonomic position: were collected and the other was left as such Phylum : Mollusca Cuvier, 1795 because of their uncommon presence. Class : Cuvier, 1795 Samples were transferred into sterile zip lock Order : Golikov & bags and were brought to the laboratory and Starobogatov, 1975 preserved in Ethyl alcohol for further studies. INDIAN J. MAR. SCI., VOL. 43, NO. 10 OCTOBER 2014

Family : Velutinidae (Lamellariidae) the presence of a shell in this (Figures. Gray, 1840 8 & 9). The shell is white in colour, very thin Genus : Coriocella Blainville, 1824 and has growth curves on it (Fig. 7). Shell has Species : hibyae (Wellens, 1991) 3 whorls with the incompletion of the third Common Name: Maldives Sponge Snail whorl (Fig. 5 & 6). Light microscopic studies of radula showed that it is taenioglossate Description: The specimens were identified radula about 2 cm long with 67 small rows of as Coriocella hibyae based on external and teeth (Fig. 10 - 12). The taenioglossate radula internal morphological characteristics. The formula is I.I.I. Canine tooth was observed on size of the specimen is about 4.5 cm long, 2.5 both right and left teeth (Fig. 13). Lateral cm broad and body possesses a central view of radula structure was also observed bulbous boss surrounded with four other under the microscope (Fig. 14). The specimen bosses. Surface colour of the body is shiny was identified as male by dissecting out the bluish green with numerous small dark brown penis (Fig. 15). . spots and ventral body surface is dark pink in colour (Fig. 2- 4). X-ray photographs revealed

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. Ireland, Mr. Sreeraj of Zoological Survey of Remarks: Coriocella hibyae was first India, Port Blair, and the authorities of described by Wellens (1991) from the Pondicherry University. The first author Republic of the Maldives and it has been thanks the Department of Science and noted as an endemic species to Maldives5. But Technology for the INSPIRE fellowship. this species was found to extend its References distribution in Indonesia, Philippines, 1. WoRMS., World register of marine Myanmar (www.nudipixel.com) and species (WoRMS). Andamans4, which shows that this species is http://www.marinespecies.eu, (2013) not an endemic species. The present study Accessed on 18-04-2013. pertains to the biology of this species which 2. Wellens, W., Coriocella hibyae sp. nov: a has not been reported from these waters. new Lamellaria species (Gastropoda: Prosobranchia) from the Republic of Acknowledgement Maldives, J. Conchol., 34(1991) 73-80. Authors thank Caren Topley of the 3. NUDI PIXEL., www.nudipixel.com, Conchological Society of Great Britain and (2013) Accessed on 09-04-2013. RAMESH et al.: OCCURRENCE OF A RARE LAMELLARID, CORIOCELLA HIBYAE

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.