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Scientists have recorded four species of azooxanthellate corals for the first time from Indian waters.

About azooxanthellate corals

• These new corals were found from the waters of Andaman and Nicobar Islands. Azooxanthellate corals are a group of corals that do not contain zooxanthellae and derive nourishment not from the sun but from capturing different forms of plankton.
• These groups of corals are deep-sea representatives, with the majority of species reporting from between 200 m to 1000 m. Their occurrences are also reported from shallow coastal waters.
• Zooxanthellate corals, meanwhile, are restricted to shallow waters.
• The details of the new records have been published in Thalassas: An International Journal of Marine Sciences in a paper titled Zoogeographic Range Extension of Four Species of Flabellid Corals Under the Genus Truncatoflabellum (Scleractinian: Flabellidae) From Indian Waters.
• All the four groups of corals are from the same family Flabellidae.
• Truncatoflabellum crassum (Milne Edwards and Haime, 1848), incrustatum (Cairns, 1989), T. aculeatum (Milne Edwards and Haime, 1848), and T. irregulare (Semper, 1872) under the family Flabellidae were previously found from Japan to the Philippines and Australian waters while only T. crassum was reported within the range of Indo-West Pacific distribution including the Gulf of Aden and the Persian Gulf.
• Azooxanthellate corals are a group of hard corals and the four new records are not only solitary but have a highly compressed skeletal structure.

• There are about 570 species of hard corals found in India and almost 90% of them are found in the waters surrounding Andaman and Nicobar Islands. The pristine and oldest ecosystem of corals share less than 1% of the earth’s surface but they provide a home to nearly 25% of marine life.