The curious case of Phyllidia ocellata and the first molecular data of three phyllidiid species from India (Gastropoda, Heterobranchia, Phyllidiidae)

ABSTRACT The current study presents the first molecular data of three species of the family Phyllidiidae, Phyllidia ocellata, Phyllidia alyta and Phyllidiella rosans, from Indian waters. The P. ocellata molecular sequences closely match those available from the Pacific Ocean, whereas P. alyta and P. rosans form independent clades, confirming their identifications as distinct species. Phyllidia ocellata, frequently found in the Indo-Pacific tropical coral reefs, is renowned for its wide range of colours and external forms. Numerous variations have been found and are being examined at the molecular level, and the subject of this study is another variation that, until dissection and molecular analysis, was thought to be a colour form of Phyllidia multituberculata. Although India has a long history of heterobranch research, no phyllidiid species from Indian waters have ever been the subject of molecular research.