Endolithic Fungal Diversity in Antarctic Oligocene Rock Samples Explored Using DNA Metabarcoding

Area of Science:

• Paleomycology
• Molecular Ecology
• Geomicrobiology

Background:

• Fungal communities within ancient rock formations remain largely unexplored.
• Understanding past microbial life provides insights into Earth's history and evolutionary processes.

Purpose of the Study:

• To characterize the fungal diversity associated with Oligocene rock cores.
• To assess the complexity and composition of ancient endolithic mycobiomes.
• To compare ancient fungal diversity with modern habitats.

Main Methods:

• DNA metabarcoding was employed to analyze fungal DNA from Oligocene rock cores.
• High-throughput sequencing identified fungal amplicon sequence variants (ASVs).
• Diversity indices and rarefaction curves were used to quantify and assess fungal diversity.

Main Results:

• A rich and complex mycobiome was detected, comprising 198 fungal ASVs across multiple phyla.
• Dominant taxa included *Pseudogymnoascus pannorum*, *Penicillium* sp., and *Aspergillus* sp.
• High fungal diversity indices were observed, with variations noted between different rock cores.

Conclusions:

• Oligocene rock cores harbor a diverse endolithic fungal community.
• The detected mycobiome is comparable in diversity to recent Antarctic habitats.
• Further research is needed to isolate these fungi for evolutionary, physiological, biogeochemical, and biotechnological studies.