Sikkim Chief Minister Prem Singh Tamang on the occasion of World Environment Day on Sunday declared Blue Duke the state butterfly.
He made the announcement at a function held here.
Of the 720 species of butterflies found in Sikkim, Blue Duke was selected as the state butterfly securing 57 per cent votes in a recent online poll conducted by the Forest Department.
Blue Duke, which goes by the scientific name Bassarona durga durga, is unique to Sikkim and the eastern Himalayas. It was discovered in the state in 1858.