[1] Sikkim Univ, Dept Bot, Taxon & Biodivers Lab, 6 th mile, Samdur, Gangtok 737102, India
[2] GB Pant Natl Inst Himalayan Environm GBPNIHE, North East Reg Ctr, Chandranagar 791113, Arunachal Prade, India
[3] Bot Survey India, Cent Natl Herbarium, Howrah 711103, W Bengal, India
[4] GB Pant Natl Inst Himalayan Environm GBPNIHE, Sikkim Reg Ctr, Gangtok 737101, Sikkim, India
[5] Sirisay, Namchi 737126, Sikkim, India
[6] Bot Survey India, 3rd MSO Bldg, Kolkata 700064, West Bengal, India