Distribution and diversity of lichenicolous fungi from western Himalayan Cold Deserts of India, including a new Zwackhiomyces species

The bare rock surfaces in cold deserts provide the most extreme environmental conditions for life on Earth where specialists with particular adaptations, such as bacteria, black yeasts, fungi, mosses, lichens and microalgae can colonize. Lichens growing in these harsh conditions also use to house symptomatic and asymptomatic fungi, which are generally termed as lichenicolous and endolichenic fungi, respectively. In the present study lichenicolous fungi associated with lichens of cold deserts of India (LehLadakh and Lahaul Spiti) were investigated using lichen specimens obtained from CSIR-National Botanical Research Institute including herbaria of LWG, LWU and private herbaria of Dr. D.D. Awasthi (AWAS). The new species Zwackhiomyces lecideae, lichenicolous on Lecidea, is described in detail, and a list of 36 species (including one lichenicolous lichen, Sarcogyne sphaerospora, and one black meristematic fungus, Lichenothelia convexa, that is also a facultative lichenicolous fungus) belonging to 11 families (excluding genera of uncertain taxonomic positions) infecting 39 species of lichen hosts in the study site is presented. The discovery of a new species of Zwackhiomyces raises the tally of its members to 36 across the world and eight from India.

Automated summary

The bare rock surfaces in cold deserts offer extreme environmental conditions where specialized organisms such as bacteria, black yeasts, fungi, mosses, lichens, and microalgae can thrive. This study focused on lichenicolous fungi associated with lichens of cold deserts in India, identifying a new species and listing a total of 36 species infecting 39 species of lichen hosts in the study site. The discovery of a new species of Zwackhiomyces increases the global count to 36, with eight of them found in India.