New Lichen Species Allographa effusosoredica Discovered in Western Ghats.
Environment
In mid‑July 2025, researchers at MACS‑Agharkar Research Institute, Pune (under the Department of Science & Technology, Government of India) formally described a novel crustose lichen species, Allographa effusosoredica, discovered in the Western Ghats. This marks the first molecularly sequenced Allographa species in India, shedding light on ancient symbiosis.
- The species Allographa effusosoredica was identified by a team led by Ansil P. A., Rajeshkumar K. C., Lücking R., and Sharma B.O., through integrated morphological, chemical, and molecular analyses (mtSSU, LSU, RPB2 for the fungus; ITS for the algal partner). The work was supported by the MACS‑Agharkar Research Institute, Pune, under the Department of Science & Technology (DST), Government of India.
- This crustose lichen features a thin, diffusely sorediate (effuse) thallus with norstictic acid—a rare compound within the genus. It forms eight-spored asci bearing transversely septate ascospores with 7–11 septa. The morphology is superficially similar to Graphis glaucescens, but genetic analyses place it firmly within Allographa, closely allied to A. xanthospora.
- The symbiotic photobiont is a strain of Trentepohlia (cf. arborum), making this one of the first tropical lichens in India whose algal component was molecularly identified. This reveals the importance of local fungal–algal co-adaptation in biodiverse ecosystems like the Western Ghats.
Main Point :- (i) Allographa effusosoredica is now the 53rd Allographa species recorded from India and the 22nd from the Western Ghats region alone. It also represents the first Indian Allographa species ever sequenced at the molecular level—a milestone in Indian lichenology.
(ii) Lichens like A. effusosoredica play multiple roles in ecosystems—from soil formation and insect food sources to serving as sensitive bioindicators of environmental health. The integrative taxonomic approach used here highlights hidden biodiversity and reinforces the need to conserve the fragile Western Ghats habitat.
(iii) Through polyphasic taxonomy combining classical morphology, chemical profiling (e.g. norstictic acid detection), and DNA sequencing of both fungal and algal partners, this study establishes a robust model for lichen classification in tropical regions. It raises important questions about the distinction between Allographa and the similar genus Graphis, pushing boundaries in fungal systematics.
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