Overview
The Giant Bracket Fungus (Phellinus ellipsoideus, formerly classified as Fomitiporia ellipsoidea) holds the astounding official world record for producing the largest, heaviest individual fungal fruiting body on planet Earth. Discovered thriving in the tropical rainforests of Hainan Island, China, by mycologist Dai Yu-Cheng, a premier specimen was documented measuring an unbelievable 35 feet (10.8 meters) in length, nearly three feet wide, and weighing an estimated half a metric ton (over 1,000 pounds). Growing continuously for over two decades across the underside of a fallen colossal hardwood trunk, it stands as an unprecedented titan of the fungal kingdom.
Biology and Physical Characteristics
Phellinus ellipsoideus is a resupinate (flat-spreading) perennial polypore bracket fungus. Rather than forming a protruding cap or shelf, the fruiting body forms a massive, hard, woody crust that spreads longitudinally across the underside of decaying fallen tree trunks. The upper non-fertile surface is deeply cracked, crustose, and dark brownish-black, while the fertile hymenial surface is a rich cinnamon-brown to golden-ochre, perforated by millions of microscopic pores (5 to 7 pores per millimeter) that produce tiny ellipsoidal basidiospores. The internal context is exceptionally dense, stratified with annual tube layers that build up over decades of continuous tropical growth.
Behavior and Ecology
Functioning ecologically as a primary white rot wood decomposer, Phellinus ellipsoideus secretes powerful lignolytic enzymes—including manganese peroxidases and laccases—that break down the tough, resistant polymers of ancient tropical hardwood timber. By decomposing massive fallen tree trunks that would otherwise take centuries to decay, it recycles vital carbon, nitrogen, and minerals back into the rainforest floor, creating nutrient-rich humus and subterranean cavities that nurture emerging tree saplings. Spores are released continuously into circulating damp ground-level drafts, colonizing fresh fallen logs across old-growth forests.
Conservation and Human Impact
While Phellinus ellipsoideus is secure across preserved old-growth national parks in southern China and Hainan, such as the Jianfengling National Forest Park and Bawangling Nature Reserve, it is fundamentally dependent on veteran deadwood in ancient primary rainforests. Commercial timber harvesting and the systematic removal of fallen logs from managed forests eliminate the colossal hardwood substrates required to support multi-decade perennial fruiting bodies. Preserving large deadwood logs in tropical protected areas is essential to sustaining these ancient fungal giants.
Interesting Factoid
In 2010 on Hainan Island, scientists discovered a single specimen of Phellinus ellipsoideus that had been growing continuously for 20 years; it weighed an estimated 1,000 pounds and measured 35 feet long—making it officially the largest mushroom fruiting body ever recorded in human history.
Last updated: October 2026