Announced October 22, 2026, Dianjunus rex is a new genus, species, and whole new family of fungus from Yunnan, China — and its lineage traces to just after the dinosaurs died out.
The discovery announcement: researchers in Yunnan found fruiting bodies up to 50 cm tall and 2.2 kg — and declared an entirely new genus, species, and family of fungus.
The science behind the find. A molecular clock dates D-rex's lineage to about 65 million years ago — roughly a million years after the asteroid wiped out the dinosaurs.
Meet the current record-holder for biggest organism alive: a single honey fungus in Oregon that sprawls across nearly 2,400 acres and may be thousands of years old.
Most of it is an invisible web of black cords called rhizomorphs, strangling trees underground across miles of forest — a single organism hiding in plain sight.
How one fungus became Earth's largest living thing — and how scientists even begin to weigh something that is almost entirely hidden beneath the soil.
D-rex belongs to the largest phylum of fungi — from baker's yeast to penicillin to deadly molds. Its fruiting body is now the biggest known in the entire group.
Genetically, fungi are closer to animals than to plants. A tour of the kingdom that quietly recycles the planet and may form its largest hidden living networks.