Growing up to 20 inches tall and weighing nearly five pounds, a giant new fungus named Dianjunus rex has been discovered deep in the forest in China’s Yunnan Province, WIRED reported.
The discovery was made by a research team from the Kunming Institute of Botany, part of the Chinese Academy of Sciences. They found the specimens growing in the soil near the roots of dying trees within the Nanban tropical rainforest.
ZME Science reported that the newly identified species has evolutionary roots stretching back roughly 65 million years. This places its emergence around the beginning of the Paleocene, following the Cretaceous-Paleogene extinction event.
D. rex is classified as a type of Ascomycete, the largest phylum of fungi with over 64,000 known species. Within this group, which includes morels, truffles, and yeasts, the giant fungus constitutes an entirely new biological family with no known close relatives.
Unlike mushrooms that typically form caps and stems, Ascomycetes produce fruiting bodies to release spores. The above-ground portions of D. rex are covered with white, powdery fibers that turn dark yellow upon maturity, while the portions buried in the soil remain black and smooth.
Researchers documented fruiting bodies growing in a wide variety of shapes, including cylinders, spindles, and cupped palms, which develop finger-like branches as they mature. ZME Science said that these reproductive structures are the largest documented within the Ascomycota group.
While 6,000 fungal species have already been documented in Yunnan, mycologists believe the province’s biological diversity could harbor up to 100,000 species.
“The discovery illustrates how much fungus biodiversity remains to be discovered in East Asian forests,” Indunil C. Senanayake, an associate professor at the Kunming Institute of Botany and the lead author of the press release, said.
Senanayake also explained the ecological context following the mass extinction event. “After the mass extinction, forests experienced dramatic changes, including the sudden availability of large amounts of dead plant material. For wood-associated decomposing fungi, such environmental disruption may have created new ecological opportunities,” he told ZME Science.
The research findings are published in the journal Frontiers in Fungal Biology.
