Endemic Fauna of Andaman and Nicobar Islands Bay of Bengal

species are exclusively distributed in Andamn Islands, 4 species in Nicobar Islands and 9
species are common to both the island groups. Of the 13 species of freshwater molluscs 11
species are occurring in Andaman group and 2 species common to both the island groups. Of
the recorded 87 species of endemic land molluscs, 41 species distributed in Andaman group,
38 species restricted to Nicobar group while 8 species common to both the islands. The
distribution of endemic species of remaining marine groups like meiofaunal components,
crustaceans, insects etc. are found largely rectricted to Andaman group of islands. The
reasons for such distribution of faunal elements can not be drawn unless through studis are
made on the faunal groups of Nicobar Islands. Due to difficulty in accessibility of Nicobar
group of islands most of the workers restricted their studies to Andaman group of islands
only. Intensive studies on lower groups certainly add several hundreds of faunal elements
with new distributional records and new to science to the existing fauna of the islands.
SUMMARY
The Andaman and Nicobar Islands located in the mid-sea of Bay of Bengal comprises
over 350 islands inaddition to large number of rocks and rock outcrops with a total land area
of 8,293 sq km covering 1,962 km of serpentine coastline. The islands are close to the
nearest landmass to the North Andamans is Cape Negaris of Myanmar coast, about 300 km
away and the Nicobars 100 km away from Achin Head of Western Sumatra. The islands
covered with 90% of various types of luxuriant forests virtually become the hotspots for
speciation due to long period of isolation from main land mases resultd in several hundreds
of endemic faunal elements at species and subspecies level. The islands are supporting over
8,386 species of animals comprising both terrestrial and marine waters. Of which, 1117
species are enedmic to the A and N islands. For major vertebrate groups common name,
diagnostic features, habitat, distribution and status of each species is given. But for lower
groups only habitat, distribution and status are given. The population status and their bilogy
of all the endemic species are not known. About 872 species of terrestrial fauna are endemic
which include protozoa, molluscs, annelids, arthropods (insects), arachnids, myriapods,
freshwater fish, amphibians, reptiles, birds and mammals while 245 species of marine fauna
are endemic include sponges, cnidarians, picnogonids, molluscs, crustaceans, fishes and
meiofauna. The terrestrial fauna is dominant with insects having 604 endemics followed by
land molluscs 100, birds 90, reptiles 32; mammals 19 and arachnids 10 species. Compared to
terrestrial fauna the marine fauna is the largest component but the endemics are less in
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