Diversity and habitat preferences of butterflies (Insecta: Lepidoptera) in Dzongu, Mangan, Sikkim, India

The butterfly diversity of the Dzongu region of Mangan District, Sikkim was assessed between 2016 and 2024, revealing the presence of 420 species from 187 genera and six families. Nymphalidae emerged as the dominant family with 165 species across 68 genera, followed by the Lycaenidae with 92 species from 51 genera, Hesperiidae with 84 species from 44 genera, Papilionidae with 38 species from eight genera, Pieridae with 32 species from 13 genera, and Riodinidae with nine species from three genera. A total 118 butterfly species that were protected under the Indian Wildlife (Protection) Amendment Act, 2022, with the majority falling under Schedule II. Very rare documents included Papilio krishna, Teinopalpus imperialis, Meandrusa lachinus, Stichophthalma camadeva, Euaspa pavo, Ionolyce helicon, Dodona adonira, and Koruthaialos butleri, the state butterfly of Sikkim Bassarona durga and the newly discovered species, Zographetus dzonguensis. A total of 194 butterfly species exclusive to the northeastern region of India were documented. It was found that the sub-tropical hill forest supported the highest butterfly diversity with 395 species recorded, and the sub-alpine forest supported the lowest diversity with 13 species. The unique geographical features of Dzongu support a wide variety of butterfly species and the presence of more than half the species in Sikkim underscores the importance of prioritizing conservation efforts in this unique valley.