Giant fungus found in China prompts new scientific classification
Dianjunus rex produces reproductive structures reaching 50 cm (20 inches), the largest known in its fungal phylum, researchers report.
A team from the Kunming Institute of Botany has discovered a fungus in Yunnan, China, with reproductive growths weighing up to 2.2 kg (4.9 pounds). Named Dianjunus rex, the species is distinctive enough to warrant a previously unrecognized genus and family, according to their study in Frontiers in Fungal Biology.
The whitish growths were found attached to woody roots of Chinese cork oak trees during forest surveys. Researchers identify these structures as the biggest fruiting bodies recorded in Ascomycota, a phylum comprising more than 64,000 recognized species.
To establish where the fungus belonged, the team examined its physical traits, cultivated its spores in a laboratory and sequenced its genome. Those findings supported placing it in the newly established family Dianjunaceae within the order Xylariales. Its scientific name references both its size and the ancient Dian kingdom.
Comparisons involving genomic information from hundreds of fungi put the lineage's estimated beginnings at approximately 65 million years ago. Researchers suggested that forest changes following the Cretaceous-Paleogene mass extinction may have offered opportunities for its wood-associated ancestors.
The reason for its size remains uncertain. The team proposed that taller reproductive growths may catch air currents more effectively, helping spores travel through dense vegetation. However, they noted that building such structures demands considerable energy, potentially limiting the environments where this strategy would be advantageous.
