Endemic Fauna of Andaman and Nicobar Islands Bay of Bengal

level. Quite a few lists of endemic species of the islands on various groups are made available (Tikader
and Das, 1985; Chakraborty, 1997; Agarwal, 1998; Mandal and Chakraborthy, 1999; Alfred and
Chakraborty, 2002 and Jayaraj and Andrews, 2005). Subsequently many species and subspecies
considered as endemics have been shifted to non-endemics and many new species have been added.
By summing up of all the available literature records, an updated list of endemics of the islands has
been prepared. About 1117 species and subspecies of animals of major groups, both vertebrate and
invertebrates, inhabiting terrestrial, freshwater and marine habitats considered endemic to the
Andaman and Nicobar Islands is presented here. For the higher vertebrate groups viz. mammals,
birds, reptiles, amphibians and fish common name, diagnostic features, habitat, distribution and
current status is given. Where as for other groups like molluscs, crustaceans, meiofaunal elements,
insects, etc. only their habitat, distribution and current staus is given as these small organisms can not
be identified to species level by the common man or an amature in the field. The literature cited in
the text is given at the end.
Physiography of the islands
The Andaman and Nicobar Archipelago comprises several hundred islands were once part of
the Asian main land but got separated over 100 million years ago during the Upper Mesozoic Period.
The archipelago can be broadly divided into two groups, namely the Andamans and the Nicobars
separated by the Ten-degree Channel which is about 150 km wide and 400 fathoms deep. The main
part of Andaman Group is collectively called as the Great Andamans comprising five adjoining islands,
viz. North Andaman, Middle Andaman, South Andaman, Baratang and Rutland islands. All these island
masses are separated by narrow channels. The southern most of the island group is Little Andaman
which is separated by a straight called Ducnan Passage. The Nicobar group comprises of about 24
islands with a total land mass of about 1,841 sq km. The northern most point of the group is Car
Nicobar Island and the southern most is Indira Point or Pigmilion Point of the Great Nicobar Island. Of
all the islands of Nicobar Group, Great Nicobar island is the largest having an area of 1,045 sq.km. The
other major islands of the group are Car Nicobar, Chowra, Tillanchong, Teressa, Bompoka, Camorta,
Trinket, Nancowry, Katchal, Pulomilo, Kondul and Little Nicobar. All the islands of the archipelago are
fertile and support evergreen vegetation. The present configuration achieved by these islands only
about 26 million years ago. The two islands, Narcondam and Barren are of volcanic origin. The
Narcondam was totally dormant and extinct for quite long period, shown the signs of eruption during
the mega earth quake took place on 26 th December 2004 and the Brren Island is highly active and
frequently erupting. The soil cover is more or less thin varying between two to five meters in the hill
tracts. The coastal flats are admixture of silty clay, sand and fragments of coral lime. The soil is
moderately acidic with high humus on top layer. The climate is of tropical nature. Due to proximity of
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