Pholiota microspora, the nameko, is a small, amber- to reddish-brown wood-decay mushroom covered in thick slime, native to the beech forests of Japan and the highlands of Taiwan. It is one of Japan's most popular cultivated mushrooms. It was long called Pholiota nameko until it was concluded in 2008 to be the same species as Agaricus microsporus, described from the Himalayas in 1850.
Edible and popular in Japanese cooking (miso soup, nabemono, stir-fries), with a slippery texture and slightly nutty taste; also sold dried. Wild collections need care: several Galerina species (e.g. G. marginata) contain deadly amatoxins and grow on decayed wood. Bitter Hypholoma fasciculare (yellow gills), scaly Pholiota species and Gymnopilus junonius can also be confused with it.
Never eat a wild mushroom based on a web page — confirm with an expert.
Mycology is an evolving science: names, classifications and safety information change as research advances. Entries are compiled from cited sources and reviewed, but may be incomplete or out of date — check the sources, and never rely on this library alone to identify or eat a mushroom.
Habitat
Singly or in clusters on dead or fallen broadleaf wood and stumps, most typically beech, also oaks; prefers humid sites such as mossy or riverside logs. Season: mainly mid to late autumn, sometimes early summer in cool conditions. Cultivated on broadleaf logs and on sawdust beds or bottles.
Distribution
Native to Japan (beech forests) and the highlands of Taiwan; the basionym was described from the Himalayas. Cultivated mainly in Japan and sold in China and elsewhere.
Characteristics
Cap: 3-10 cm, hemispherical becoming flat; reddish brown to pale brown, covered by a thick gelatinous layer. Gills: attached, crowded, pale yellow becoming pale brown; covered by a gelatinous veil when young. Stem: 5-8 cm long, solid, even in thickness; white above a gelatinous ring zone, slimy below. Flesh: yellowish white. Spore print: brown. Key features: clustered growth on broadleaf wood, heavy slime on cap and lower stem.
Difficulty
Intermediate
Growth speed
Slow
Contamination risk
Medium
Substrates
Hardwood sawdust with rice or wheat bran · Conifer sawdust with 15% rice bran · Straw with rye or wheat grain · Broadleaf hardwood logs