In News:

A team of Indian scientists from MACS-Agharkar Research Institute, Pune (under the Department of Science & Technology) has discovered a new species of lichen named Allographa effusosoredica in the Western Ghats, a UNESCO World Heritage Site and biodiversity hotspot. This crustose lichen exhibits effuse soredia and contains norstictic acid, a rare secondary metabolite within its genus.

Scientific and Molecular Significance

• The species was examined through polyphasic taxonomy, integrating:
  • Morphological traits
  • Chemical profiling
  • Molecular sequencing using genetic markers:
    • Fungal DNA markers: mtSSU, LSU, RPB2
    • Algal symbiont marker: ITS
• The lichen’s photobiont was identified as a species of Trentepohlia, advancing the understanding of tropical algal diversity in lichens.
• Though morphologically similar to Graphis glaucescens, it is phylogenetically closest to Allographa xanthospora.

Symbiosis in Lichens

• Lichens are composite organisms, formed by a symbiotic association between:
  • A fungal partner (mycobiont) — provides structure and protection.
  • A photosynthetic partner (photobiont), such as green algae or cyanobacteria — produces nutrients via photosynthesis.
• This discovery supports the concept of locally adapted symbiosis, emphasizing co-evolution in tropical ecosystems.

Ecological Importance of Lichens

• Lichens are vital for:
  • Soil formation
  • Feeding insect populations
  • Acting as bioindicators of air quality and ecosystem health.

Conservation and Biodiversity Impact

• Allographa effusosoredica is:
  • The 53rd Allographa species reported from India.
  • The 22nd species of this genus documented in the Western Ghats.
  • The first Indian Allographa species validated using molecular tools.
• The study was supported by the Anusandhan National Research Foundation (ANRF) and contributes to the growing inventory of India’s cryptic biodiversity.