Researchers discover giant fungus in China dating back to dinosaur extinction

Researchers identified a massive new fungus species in the tropical and subtropical forests of Yunnan province, China.

The team discovered the pale-yellow organism, which can grow half a meter tall, while conducting diversity surveys in Kunming, Xishuangbanna, and Chuxiong. The fungus, named Dianjunus rex, belongs to the Ascomycota group. It produces reproductive structures called stromata that are the largest ever documented in this group.

While most collected specimens weighed between 250 and 600 grams, the researchers found one individual weighing 2.2 kilograms. The team established a new family, Dianjunaceae, to classify the species because its genetic profile is so distinct from other known fungi. Genetic analysis suggests the fungus emerged approximately 65 million years ago, coinciding with the mass extinction of the dinosaurs.

Researchers believe the environmental upheaval of that period, which left large amounts of dead plant material, may have provided a unique ecological opportunity for this lineage to develop. The fungus likely lives inside healthy trees as an endophyte before switching to a decomposer lifestyle once the host dies. The researchers noted that while they have documented more than 6,000 fungal species in Yunnan, the province likely contains over 100,000 species.

Many remain hidden underground or inside hosts, only appearing under specific conditions. The team published their findings in the journal Frontiers in Fungal Biology.