Melzer's reagent), thin-walled, and measure 11.5–14 by 6–8 µm. The spore-bearing cells, the basidia, are 17–28 by 6–8 µm, club-shaped, and four-spored. The basidioles (immature or aborted basidia) are club-shaped. The cheilocystidia (cystidia found on the gills edges) are 32–39 by 5–12 µm, abundant, spindle-shaped to roughly club-shaped, often apically broadly rounded, smooth, colorless, and thin-walled. They form a sterile gill edge. Pleurocystidia (cystidia on the gill faces) are absent in this species. The hymenophoral tissue (tissue of the hymenium-bearing structure) is made of thin-walled hyphae that are 7–15 µm wide, cylindrical, smooth, colorless, and dextrinoid (staining reddish to reddish-brown in Melzer's reagent). The cap cuticle is made of parallel, bent-over hyphae that are 2–5 µm wide, cylindrical, and densely covered with warty or finger-like thin-walled diverticulae that are colorless or contain cytoplasmic brownish pigment. The layer of hyphae underlying the cap cuticle are parallel, colorless or with cytoplasmic brownish pigment, dextrinoid, and have short and inflated cells measuring up to 30 µm wide. The stem cuticle is made of parallel, bent-over hyphae that are 3–5 µm wide, and cylindrical. These hyphae are covered with scattered, thin-walled warty or finger-like diverticulae that can be either colorless, or contain brownish pigment in the cytoplasm. The flesh of the stem is made of longitudinally running, cylindrical hyphae that are 5–17 µm wide, smooth, colorless, and dextrinoid. Clamp connections are absent in all tissues of this species. Similar species Mycena mustea is another similar Mycena that was discovered and reported concurrently with M. fonticola; it 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, 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 Q. serrata. References External links The Agaricales in Southwestern Islands of Japan Images of the holotype specimen fonticola Fungi of Asia Fungi described in 2007