Lichen diversity in the Eastern Himalaya biodiversity hotspot region, India

Abstract

Eastern Himalaya, a part of the Himalaya biodiversity hotspot region has been assessed for its
lichen diversity, based on the own collections, identifications, field observations and published
literature. Out of ca 2540 species so far, known from India, 1047 species,1 sub species and 4
varieties distributed in 592 crustose, 321 foliose, 125 fruticose and 9 squamulose growth forms
under 212 genera and 63 families, occurring as corticolous, saxicolous, terricolous, foliicolous,
and muscicolous constitute c. 41.22 % of the total lichen diversity of the country. The lichen
vegetation is recognized into four major types and discussed under (i) tropical lichen vegetation
(ii) sub tropical lichen vegetation (iii) temperate lichen vegetation and (iv) subalpine and alpine
lichen vegetation. A comparative statistics of diversity of species under dominant families and
genera at India and Eastern Himalaya level is given. The region is also active centre of speciation
and represented by 107 endemic species including many point endemics. It is pointed out that
this rich diversity of lichens is under threat due to various biotic activities. Therefore, conservation
measures concerning rich lichen diversity in brief are also discussed. It is also suggested that
unexplored high altitude areas are required to be explored thoroughly for getting complete knowledge
of the lichen diversity of the region and finally its utilization for the welfare of human beings.