Seventeen Brachyuran crab species found in Andaman and Nicobar Islands

The Andaman and Nicobar Islands have been found to be home to different species of deep-water Brachyuran crabs, a recent survey carried out by Center for Marine Living Resources Ecology (CMLRE) noted.

Brachyuran crabs bear immense ecological and economic significance. They are not only an important source of protein but also a rich source of carbohydrates, lipids, vitamins and minerals, helping the fisheries industry flourish.

The deep-water survey, carried out with the help of Fisheries Ocean Research Vehicle Sagar Ratna, has revealed the presence of seventeen species of Brachyuran crabs, including three species which were recorded for the first time in the area.

Most importantly, the CMLRE survey spotted the seventeen crab species in newer areas of the ocean. These crabs are ecologically important for being both a predator and prey in the marine food web.

Brachyuran crabs also play a key role in the deep-water ecosystem. They help “clean up” the sea bottom by harvesting decomposing plants and animals, thus helping in detritus formation, nutrient recycling, and dynamics of the ecosystem. Crabs are also used to cure different ailments like stomach ache, liver and lung diseases, and heal wounds, osteoporosis, epilepsy, and reproductive malfunction in women, among others.

The research team, for the first time, found a rare porter crab ‘Homolochunia valdiviae Doflein, 1904’, inhabiting a wide depth of 395-1000 metres in the Northern Indian Ocean, previously known only to be in the Western Indian and Western Pacific Ocean regions.

Another species of deep-water elbow crab ‘Dairoides seafdeci Takeda and Ananpongsuk’, 1991, which is endemic to the Andaman Sea, was found for the first time in the Indian Exclusive Economic Zone (EEZ) with a relatively narrow depth range of 299–633 meters.

A third species of deep-water pebble crab ‘Parilia pattersoni PKL Ng, Devi and AB Kumar’, 2018, earlier found in western Bay of Bengal, got recorded by the CMLRE research team for the first time in both the Andaman Sea and Arabian Sea.

The research team comprised Sherine Sonia Cubelio, VP Padate, Narayanane Saravanane, and Maruthadu Sudhakar of CMLRE, Ministry of Earth Sciences, Cochin, besides KM Amritha of Kerala University of Fisheries and Ocean Studies (KUFOS) and eminent carcinologist Professor PKL Ng of the National University of Singapore.

The research paper is published in the Journal of Regional Studies in Marine Science.

(With inputs from India Science Wire)