Guwahati, July 10: A study on butterfly diversity has recorded 343 species of the insect in Barail wildlife sanctuary in south Assam.

The study, published in the Journal of Entomology and Zoology Studies, by Monsoon Jyoti Gogoi, Hillol Jyoti Singha and Panna Deb, from December 2012 to April 2016, found two new additions to Indian butterfly fauna - Fawcett's Pierrot (Niphanda asialis marcia) and Multi-spotted Oakblue ( Arhopala anthelus). This record of 343 species is significant because it stands second to Kaziranga which has around 430 types of butterflies.

Gogoi, a butterfly expert, told The Telegraph that the two new butterflies, which are blue, are additions to the Malayan species from the sanctuary.

The Malayan region refers to the Malay peninsula, which includes south Myanmar, Thailand and some part of Malaysia.

"There are lots of Malayan species which are not found together in any other place of the Northeast which supports the fact that Barail wildlife sanctuary is a stronghold of Malayan butterflies," Gogoi said.

An Englishman named Sir Keith Cantlie during the fifties had mentioned that more Malayan butterflies can be seen in Dima Hasao (then North Cachar Hills) district in comparison to Khasi hills in Meghalaya.

These species were till now found only in Myanmar and Thailand but not in India.

However, on February 3, 2013, Fawcett's Pierrot ( Niphanda asialis marcia) was sighted in Jaintia-Cachar hills boundary by Gogoi, which turned out to be the first record of the species from India.

Later, it was found to be quite common in Barail wildlife sanctuary.

Subsequently, on February 7, 2013, another blue butterfly known as Multi-Spotted Oakblue ( Arhopala anthelus) was sighted by Gogoi and Rajkamal Goswami from Jaintia-Cachar hills boundary, which also turned out to be another new record for India.

Since then, the species was found once in East Jaintia Hills, but quite often seen in Barail wildlife sanctuary.

Barail wildlife sanctuary is the lone one in the entire southern Assam, with an area of 326.24 square km, and is also one of the last remaining contiguous forest tracks left in south Assam.

The vegetation of the sanctuary is represented by tropical evergreen, semi-evergreen in "human disturbance area" in lower elevation and moist deciduous at mid-elevation.

"Many species recorded during earlier surveys could not be found during the study. This shows that some of them may be locally extinct from the area because of change in climate or habitat, or there is need for more survey in near future," the study said.

It says despite its potential, the wildlife sanctuary has not been given due importance and is still undergoing heavy degradation owing to logging and other anthropogenic activities.