Dianjunus rex Discovered in Yunnan Forests as New Fungal Family
Scientists have discovered a new species of fungus in the forests of China's Yunnan province that reaches up to 50 centimeters in height and represents an entirely unknown family of organisms.
Field Expeditions Across Yunnan Yield Massive Specimens
Field campaigns conducted between August 2024 and July 2025 across the tropical and subtropical forests of Yunnan brought the specimens to light. The fungi grow in association with tree roots and surrounding soil, producing fleshy structures that rise vertically from the ground. While most collected samples weighed between 250 and 600 grams, the largest recorded specimen tipped the scales at 2.2 kilograms. These towering reproductive structures, known as stromas, measure between 20 and 50 centimeters in height, making them the largest documented structures within the ascomycetes group, which includes truffles and yeasts.
DNA Analysis Establishes a New Evolutionary Branch
Genomic sequencing and physical comparisons revealed that the organism occupies a distinct evolutionary branch within the order Xylariales. The genetic distance and unique traits justified the creation of a new genus, Dianjunus, and a completely new family, Dianjunaceae. Evolutionary analysis places the separation of this family around 65 million years ago. This timeline aligns with the Cretaceous-Paleogene extinction event, when an asteroid impact triggered a mass extinction that wiped out non-avian dinosaurs and roughly 75 percent of Earth’s species. Researchers suggest that ecosystem reorganization after the catastrophe may have opened up new ecological niches for wood-associated fungi, though direct causality remains unproven.
Frequently Asked Questions About Dianjunus rex
Where exactly were the specimens found?
The specimens were discovered during exploration campaigns carried out between August 2024 and July 2025 in the tropical and subtropical forests of China’s Yunnan province.
How does the size of Dianjunus rex compare to other fungi?
While some fungi possess underground mycelial networks covering vast areas, Dianjunus rex produces individual reproductive structures, or stromas, that reach up to 50 centimeters in height and weigh as much as 2.2 kilograms, setting a size record for the ascomycetes group.
What is the proposed evolutionary timeline for this new family?
Genetic analysis estimates that the Dianjunaceae family separated approximately 65 million years ago, coinciding with the mass extinction event at the end of the dinosaur era.