New Lichen Species Allographa effusosoredica in the Western Ghats

Lichens are symbiotic organisms formed through a partnership between fungi and photosynthetic partners—usually green algae or cyanobacteria. These organisms play vital ecological roles such as soil formation, air pollution monitoring, and sustaining food chains. The genus Allographa belongs to the family Graphidaceae and is largely found in tropical environments, including the Western Ghats, a UNESCO World Heritage site and one of the world’s biodiversity hotspots.

Significance

The discovery of Allographa effusosoredica by scientists from MACS-Agharkar Research Institute, Pune, marks the first Indian Allographa species supported by molecular data. This breakthrough advances India’s understanding of tropical lichen diversity and sets new benchmarks in the use of integrative taxonomy—combining classical identification with modern DNA-based techniques.

Key Features

The new lichen species is characterized by effuse soredia (a type of asexual reproductive structure) and a rare chemical, norstictic acid, which differentiates it from similar species. The lichen’s photobiont partner was identified as a Trentepohlia species, enriching the knowledge of algal diversity in tropical symbioses. Morphologically, it closely resembles Graphis glaucescens, although it is genetically aligned with Allographa xanthospora, raising important questions on evolutionary relationships within the Graphidaceae family.

Impact

This study enhances India’s lichen inventory, making A. effusosoredica the 53rd Allographa species reported from India and the 22nd from the Western Ghats. It highlights the evolutionary complexity of lichens and underlines the importance of molecular techniques in biodiversity research. The project was supported by the Anusandhan National Research Foundation (ANRF) and contributes to global efforts in symbiosis research and ecological conservation.