Mycena intersecta is a species of mushroom in the family Mycenaceae. First reported as a new species in 2007, it is known only from central Honshu, in Japan, where it is found growing solitarily or scattered, on dead leaves in lowland forests dominated by oak. The mushrooms have olive-brown caps up to in diameter atop slender stems that are long by thick. On the underside of the cap are the distantly spaced, whitish gills that have cross-veins running between them. Microscopic characteristics of the mushroom include the smooth, irregularly cylindrical cheilocystidia (cystidia on the gill edge), the absence of pleurocystidia (cystidia on the gill face), the diverticulate elements of the cap cuticle, the broadly club-shaped to irregularly shaped caulocystidia (cystidia on the stem), the weakly dextrinoid flesh (staining reddish to reddish-brown in Melzer's reagent), and the absence of clamp connections. The edibility of the mushroom is unknown. Taxonomy and naming The mushroom was first collected by Japanese mycologist Haruki Takahashi in 1999, and published as a new species (along with seven other Japanese Mycenas) in a 2007 publication. The specific epithet is from the Latin word intersecta or "intersected", and refers to the intervenose gills. Its Japanese name is Oriibu-ashinagatake (オリーブアシナガタケ). According to Takahashi, the fungus is best classified in the section Fragilipedes (Fr.) Quél., as defined by the Dutch Mycena specialist Maas Geesteranus. Description The cap of M. intersecta is initially conical to convex to bell-shaped, eventually reaching in diameter. When it is moist, it is partly translucent, so that the outlines of the gills underneath the cap can be seen. The cap is somewhat hygrophanous, and dry. Its surface is initially minutely pruinose (as if covered with a fine white powder), but this effect soon sloughs off, leaving the surface smooth. The cap color is initially olive-brown to yellowish-brown, then somewhat paler from the margin. The white flesh is up to 0.7 mm thick, and lacks any distinctive taste and odor. The slender stem is long by thick, cylindrical, and hollow. Its surface is dry, and colored pale olive-brown near the top, becoming olive-brown downward. Like the cap, it is at first pruinose, but smooths out in age. The base of the stem is covered with coarse white hairs. The gills are adnate to subdecurrent (running slightly down the length of the stem), and distantly spaced, with 16–19 gills reaching the stem. The gills are up to 1.5