Record-Sized Fungus From China Belongs to a New Family
Researchers described Dianjunus rex, a fungus from Yunnan, China, whose spore-bearing structures reach 50 cm tall and weigh up to 2.2 kg. It has the largest fruiting bodies known in Ascomycota and belongs to a previously unknown family. DNA evidence suggests the family may have appeared about 65 million years ago, and the large size may help spores disperse in dense forest.
Dianjunus rex was collected in Yunnan at temperate coniferous sites near Damaidi and Yipinglang and in tropical rainforest near Nanbang. Its upright spore-bearing stromata emerge from soil around Chinese cork oak roots; voucher specimens were preserved at the Kunming Institute of Botany. Researchers cultured spores and sequenced protein-coding genes, leading to a new genus, species, and family, Dianjunaceae, within Xylariales.
Its nearest known relative, Graphostroma platystoma, lives on dead hardwood in the Northern Hemisphere and is the only member of Graphostromataceae. The authors estimate the new family may have arisen roughly 65 million years ago, soon after the extinction that ended non-avian dinosaurs. Other Xylariales produce secondary compounds and plant-degrading enzymes.
The discovery could expand scientific understanding of fungal diversity and evolution, affecting researchers, conservation planners, and forest managers who rely on biodiversity surveys. It may also draw attention to East Asian forests as reservoirs of undescribed fungi, potentially influencing bioprospecting and habitat-monitoring priorities. Because related fungi can break down plant material and produce secondary compounds, future studies could inform enzyme or natural-product research, though practical benefits remain uncertain.