Mycena fonticola is a species of fungus in the family Mycenaceae. First described in 2007, it is known only from central Honshu, Japan, where it grows on dead leaves and twigs in low-elevation forests dominated by oak trees.
Taxonomy, Naming, and Classification
The fungus was first collected by Japanese mycologist Haruki Takahashi in 1999 and described as a new species in a 2007 publication in the journal Mycoscience, along with seven other Japanese Mycena species. The specific epithet fonticola is derived from Latin, meaning "dweller in fountain." Its Japanese name is Izumino-ashinagatake (イズミノアシナガタケ). Based on macro- and microscopic features, Takahashi classified this species in the section Fragilipedes (Fr.) Quél., as defined by the Dutch Mycena specialist Maas Geesteranus.
Description
Cap: 1 to 2.5 cm (0.4 to 1.0 in) in diameter, ranging in shape from conical to convex to bell-shaped. The surface has radially arranged shallow grooves extending almost to the center. It is somewhat hygrophanous (changing color as it loses or absorbs water), dry, and smooth. Colored violet-brown when young, becoming somewhat paler from the margin. The white flesh is up to 1 mm thick and lacks any distinctive odor or taste.
Stem: 7 to 10 cm (2.8 to 3.9 in) tall by 1 to 2.5 mm (0.04 to 0.10 in) thick, cylindrical, slightly enlarged at the base, and hollow. Grayish-brown to violet-brown at the top, gradually becoming violet-brown on the lower portion. The surface is initially pruinose (covered with a fine whitish powder) but becomes smooth in age. The stem base bears large, bristle-like coarse white hairs.
Gills: Adnexed (narrowly attached to the stem), with 23 to 27 reaching the stem. Up to 2.5 mm broad, thin, whitish or with a grayish hue; edges concolorous with the gill faces.
Microscopic Characteristics
- Spores: Ellipsoid, smooth, colorless, distinctly amyloid (turning blue to black when stained with Melzer's reagent), thin-walled, measuring 11.5–14 by 6–8 μm.
- Basidia: 17–28 by 6–8 μm, club-shaped, four-spored.
- Cheilocystidia (cystidia on gill edges): 32–39 by 5–12 μm, abundant, spindle-shaped to roughly club-shaped, often apically broadly rounded, smooth, colorless, thin-walled, forming a sterile gill edge.
- Pleurocystidia (cystidia on gill faces): Absent.
- Hymenophoral trama: Thin-walled hyphae 7–15 μm wide, cylindrical, smooth, colorless, dextrinoid (staining reddish to reddish-brown in Melzer's reagent).
- Cap cuticle: Parallel, bent-over hyphae 2–5 μm wide, cylindrical, densely covered with warty or finger-like thin-walled diverticulae.
- Stem cuticle: Parallel, bent-over hyphae 3–5 μm wide, cylindrical, covered with scattered, thin-walled warty or finger-like diverticulae.
- Clamp connections: Absent in all tissues.
Similar Species
Mycena mustea, described concurrently with M. fonticola, is similar but differs in forming a pale grayish purple cap with a low and broad umbo. Microscopically, it has club-shaped cheilocystidia with several apical short finger-like outgrowths and nondiverticulate hyphae in the stem cuticle.
Habitat and Distribution
Mycena fonticola is known only from Kanagawa Prefecture in central Honshu, Japan. Fruit bodies are found solitary or scattered, on dead leaves and twigs in low-elevation forests dominated by the oak species Quercus myrsinaefolia and Quercus serrata.
References
- Takahashi H. (2007). "Eight new species of the genus Mycena from central Honshu, Japan". Mycoscience 48 (6): 342–357. doi:10.1007/s10267-007-0376-2.
- Index Fungorum. "Mycena fonticola Har. Takah." CAB International. Record ID: 532055.
