Oak-stump bonnet cap

Appearance

The cap is light reddish-brown, with a diameter typically ranging from 1 to 4.5 cm. Initially conic to bell-shaped to convex, it flattens during maturity, developing visible surface grooves corresponding to the gills underneath the cap. The margin of the cap has minute but distinct scallops. The surface is moist and smooth, and hygrophanous. The cap frequently develops splits in the margin, or cracks in the disc. The flesh of the cap is thick in the center but thin elsewhere, grayish to whitish, fragile, and with a slightly mealy odor and taste. The gills have a decurrent attachment to the stem and are a pale brownish color with tinges of red. They are broad, and have a close to subdistant spacing, with about 26–35 gills reaching the stem. The fragile stem is 3 to 9 cm long by 0.15 to 0.4 cm thick and yellow to yellow-brown, becoming reddish-brown to orange-brown in the bottom half in maturity. The lower portion of young stems is covered with white flecks. Roughly equal in thickness at the top and bottom, the base of the stem is covered by a yellowish mycelium that can be up to a third of the length of the stem. The edibility of the mushroom is "doubtful" and consumption "best avoided".The spores are 7–9 by 5–6.5 μm, broadly ellipsoid, smooth, and strongly amyloid. The basidia are four-spored. The pleurocystidia are not differentiated. The cheilocystidia are embedded in the gill edge and very inconspicuous, club-shaped, 26–36 by 5–10 μm, and have tips that are covered with contorted projections that can be slender or thick. The flesh of the gills is homogeneous, and pale yellowish to dirty brown when stained in iodine. The flesh of the cap has a distinct pellicle, a well-differentiated hypoderm, and a filamentous tramal body; it is pale yellowish to sordid brownish in iodine stain.

Naming

First described as "Agaricus inclinatus" by Swedish mycologist Elias Magnus Fries in 1838, it was assigned its current name in 1872 by Lucien Quélet. "Mycena galericulata" var. "calopus", and its basionym "Agaricus galericulatus" var. "calopus", are synonyms.

In a molecular study of the large subunit ribosomal DNA sequences of mycorrhizal fungi of the orchid "Gastrodia confusa", "M. inclinata" was found to be closely related to "M. aurantiomarginata", "M. crocata", and "M. leaiana".

The specific epithet "inclinata" means "bent in". The mushroom is commonly known as the "clustered bonnet" or the "oak-stump bonnet cap".
"Mycena maculata" bears some resemblance to "M. inclinata", but is only associated with decaying hardwood logs and stumps, and is found in eastern North America, and sometimes on oak on the West Coast. In age, it develops reddish spots on the gills that are not seen in "M. inclinata". "M. inclinata" is often confused with the edible "M. galericulata", a common species that is variable in cap color, size and shape. "M. galericulata" typically has a bluntly conical cap that is dull gray-brown, and white to grayish veins that have numerous cross-veins. "M. polygramma" has a ridged stem that is bluish-gray.

Distribution

"Mycena inclinata" is a saprobic fungus, deriving its nutrients from decomposing organic matter found in plant litter such as leaves, twigs, bark and branches. It accomplishes this by producing enzymes capable of breaking down the three major biochemical components of plant cell walls found in litter: cellulose, hemicellulose and lignin.

The fruit bodies of "Mycena inclinata" grow in dense groups or clusters on decaying hardwood logs and stumps during the spring and autumn. The fungus forms a white, woolly mycelium on the surface of decomposing oak leaves. Occasionally, it can be found growing on a living tree. In eastern North America, it is abundant in the area bounded by Nova Scotia, Ontario, Manitoba, Missouri, North Carolina, and New York. It has been found in Oregon, but the species appears to be generally rare along the Pacific Coast. The range of the fungus also includes Europe, the Canary Islands, North Africa, East Siberia, Japan, Malesia, Turkey, and New Zealand.

Habitat

"Mycena inclinata" is a saprobic fungus, deriving its nutrients from decomposing organic matter found in plant litter such as leaves, twigs, bark and branches. It accomplishes this by producing enzymes capable of breaking down the three major biochemical components of plant cell walls found in litter: cellulose, hemicellulose and lignin.

The fruit bodies of "Mycena inclinata" grow in dense groups or clusters on decaying hardwood logs and stumps during the spring and autumn. The fungus forms a white, woolly mycelium on the surface of decomposing oak leaves. Occasionally, it can be found growing on a living tree. In eastern North America, it is abundant in the area bounded by Nova Scotia, Ontario, Manitoba, Missouri, North Carolina, and New York. It has been found in Oregon, but the species appears to be generally rare along the Pacific Coast. The range of the fungus also includes Europe, the Canary Islands, North Africa, East Siberia, Japan, Malesia, Turkey, and New Zealand.