New Lichen Species Discovered in Western Ghats Expands India’s Fungal Map

In a groundbreaking discovery that underscores the rich and largely untapped biodiversity of the Western Ghats, a team of Indian scientists has identified a new species of lichen, Allographa effusosoredica, marking a milestone in the study of symbiotic organisms and evolutionary biology in India. The newly described species is the first of its genus in India to be fully characterized using molecular sequencing, setting new standards for taxonomic research in tropical lichens.

The discovery was led by researchers Ansil P. A., Rajeshkumar K. C., Sruthi O. P., and Bharati O. Sharma at the MACS-Agharkar Research Institute, Pune, an autonomous institution under the Department of Science and Technology (DST), Government of India. Their work was supported by the Anusandhan National Research Foundation (ANRF)—formerly known as the Science and Engineering Research Board (SERB)—under a project focused on unraveling fungal-algal partnerships in lichens using modern ecological and molecular tools.

The Lichen World: A Complex Symbiosis

Lichens are often misunderstood as simple mossy patches clinging to tree trunks and rocks. In reality, they are intricate symbiotic life forms composed of at least two distinct partners: a fungal component (mycobiont) that provides structure and protection, and a photosynthetic partner (photobiont)—either a green alga or cyanobacterium—that produces food through photosynthesis. Their partnership is one of nature’s oldest and most successful examples of symbiosis.

The new species, Allographa effusosoredica, belongs to a group of crustose (crust-like) lichens known for their discrete, often inconspicuous appearance. However, its distinctive features make it stand out in the genus.

What Makes Allographa effusosoredica Unique?

Discovered in the lush terrain of the Western Ghats, a UNESCO World Heritage site and global biodiversity hotspot, A. effusosoredica displays:

• Effuse soredia: Powdery outgrowths that help it reproduce asexually, appearing as a wide dispersal across the surface (rather than clustered)

• Presence of norstictic acid: A rare chemical compound among its genus that aids in distinguishing it from morphologically similar species

• Trentepohlia algal partner: An important find in understanding the specificity and adaptability of photobionts in tropical lichen communities

These traits were verified through a polyphasic approach, combining traditional morphological observation with chemical analysis (spot tests and thin-layer chromatography) and multi-gene molecular sequencing. The genes used included:

• mtSSU, LSU, and RPB2 for the fungal DNA

• ITS marker for the algal partner

This integrative method allowed researchers to confidently place the new species phylogenetically close to Allographa xanthospora—a known member of the Graphidaceae family. Intriguingly, its physical appearance closely mimics Graphis glaucescens, raising compelling questions about evolutionary convergence and taxonomic boundaries within the family.

A Scientific First for India

This is the first time a species from the genus Allographa has been molecularly sequenced in India, bringing credibility and rigor to Indian lichen taxonomy. With this discovery, A. effusosoredica becomes the 53rd species of Allographa reported from India, and the 22nd from the Western Ghats region alone—a clear signal of the area's rich lichen biodiversity and the need for continued exploration.

The study also offers a rare glimpse into lichen-algal symbiosis, reinforcing the hypothesis that tropical lichens often harbor locally adapted algal partners, a phenomenon still poorly understood globally.

Why It Matters

Lichens may appear modest, but they are ecological powerhouses. They:

• Fix atmospheric nitrogen

• Break down rocks and help form soil

• Provide food for insects and nesting material for birds

• Serve as bioindicators of air pollution and climate change, reacting sensitively to environmental changes

In India, despite hosting one of the world’s richest floral and faunal diversities, lichen studies remain underrepresented, especially those that involve molecular data. The discovery of A. effusosoredica highlights the urgent need for more molecular taxonomy and ecological research, particularly in biodiversity hotspots like the Western Ghats, the Eastern Himalayas, and the Andaman-Nicobar Islands.

Building a National Lichen Inventory

The work by the Agharkar Research Institute contributes significantly to India’s efforts to build a comprehensive inventory of its lichen biodiversity. This also feeds into global databases that aim to track and understand how climate, pollution, and land-use change affect these symbiotic organisms.

With changing climate patterns and increasing habitat degradation, such discoveries are not just academic—they are urgent. They help us understand the resilience of ecosystems, the subtle interplay of organisms, and how even the smallest life forms carry evolutionary stories spanning millennia.

A Window into Hidden Worlds

The discovery of Allographa effusosoredica is not just the addition of a name to a species list—it is a scientific achievement, a testament to Indian research excellence, and a call for deeper investment in biodiversity science. As the world becomes increasingly aware of the interconnectedness of life, these “silent sentinels” offer a window into the resilience, adaptability, and complexity of nature.