What You Should Know
Hygrophoropsis rufa is a species of fungus in the family Hygrophoropsidaceae. It is rare and found in Europe, where it grows on woodchips or near conifer stumps. Cap up to 10 cm, orange brown to brown; cap margin incurved. Stipe usually tapering towards the base, concolorous with the cap. Flesh orange, unchanging when exposed to air. Gills orange, decurrent (running down the stipe), forked. Smell and taste not distinctive.
Hygrophoropsis rufa Mushroom Identification
Cap diameter 3-10cm. Initially convex, caps usually expand to become shallow funnels but occasional specimens remain slightly domed or simply flat when fully mature; surface dry, matt to finely or granularly tomentose. Cap color orange-brown to dark brown. The cap margin remains slightly inrolled and is often wavy and irregular.
Bright orange when young and fresh, becoming yellower when old, the repeatedly-forking gill-like spore-producing structures are deeply decurrent and narrow.
Typically 3 to 5cm tall and 5 to 10mm in diameter, the upper parts of the tough stems of Hygrophoropsis rufa are the same color as the cap, while the stem base is white tomentose. The fibrous flesh is orange buff.
Ellipsoidal to ovoid, smooth, thick-walled, 5.6-6.4 x 3.6-4.4μm; dextrinoid.
Habitat & Ecological Role
A rare species, H. rufa has been recorded in the United Kingdom, Austria, Germany, and Denmark, although unconfirmed internet photos suggest a wider range that includes France and Slovakia. A saprophytic fungus, it fruits on woodchips or near conifer stumps.
Hygrophoropsis rufa Look-Alikes
Has a paler yellow-orange cap and significantly larger thin-walled spores.
Popular edible species found in similar woodland habitats, has wrinkled veins rather than gills.
Hygrophoropsis rufa Taxonomy
Originally described by Derek Reid in 1972 as a variety of Hygrophoropsis aurantiaca, it was raised to distinct species status in 2008. Molecular analysis of DNA sequences confirms its genetic uniqueness, and its status as sister species to H. aurantiaca.
Photo 1 - Author: 2012-01-28_Hygrophoropsis_aurantiaca_(Wulfen)_Maire_197125.jpg: (Creative Commons Attribution-Share Alike 3.0 Unported)
Photo 2 - Author: Holger Krisp (Creative Commons Attribution 3.0 Unported)
Photo 3 - Author: Holger Krisp (Creative Commons Attribution 3.0 Unported)
Photo 4 - Author: Jason Hollinger (Creative Commons Attribution 2.0 Generic)
Photo 5 - Author: Jason Hollinger (Creative Commons Attribution 2.0 Generic)