Mycena pseudocorticola

On moss-covered bark of various living deciduous trees. Autumn to winter. Widely distributed in South Norway. See records in The Norwegian Mycology Database.

Pileus 2-12 mm across, hemispherical, parabolical, broadly conical to convex, occasionally with a small papilla, often somewhat flattened at the centre, sulcate, translucent-striate, pruinose, glabrescent, dark bluish grey, bluish to bluish grey, or slate grey, turning brownish with age. Lamellae 8-14 reaching the stipe, fairly broad, ascending to subhorizontal, the edge convex, broadly adnate, mostly decurrent with a short tooth, grey to pale bluish grey, or greyish white, becoming pale sepia brown with age, the edge paler. Stipe 5-25 x 0.2-1 mm, equal, curved, pruinose-floccose, glabrescent, grey to bluish grey, more brownish with age, the base densely covered with long, white fibrils. Odour none.

Basidia 25-36 x 9-12 µm, clavate, 4-spored and clamped or 2-spored and clampless, with plump sterigmata up to 13 µm long. Spores from 4-spored basidia 8-10.5 x 7.5-10 µm, from 2-spored basidia up to 13 x 12 µm, Qav ~ 1.1, globose to subglobose, smooth, amyloid. Cheilocystidia 12-54 x 6-25 µm, occuring mixed with basidia, clavate, clamped or clampless, covered with unevenly spaced, simple to branched, curved to tortuous excrescences up to 20 µm long. Pleurocystidia absent. Lamellar trama dextrinoid, staining red-brown in Melzer’s reagent. Hyphae of the pileipellis 2-5 µm wide, covered with cylindrical excrescences. Hyphae of the cortical layer of the stipe diverticulate, the terminal cells 25 - 37.5 µm long, diverticulate.

Mycena pseudocorticola and M. meliigena (Berk. & Cooke) Sacc. can often be found growing together on the same trunk. M. pseudocorticola seems to be a little bit more common. Young, fresh specimens of the two species are not difficult to separate, but with age they both turn more brownish and can be hard to identify macroscopically. Microscopically they are very similar too. Maas Geesteranus (1982a) pointed at a quite reliable character to tell them apart in the shape and size of the terminal cells of the stipe cortex. In M. pseudocorticola these cells are stubby, not longer than 37 µm, whereas much longer, more slender, cells are by far the more common kind in M. meliigena.

The brown colours in older specimens may cause confusion with M. supina (Fr.) P. Kumm., but that species have cheilocystidia with only short excrescences. M. juniperina Aronsen has a pale yellowish brown pileus and grows on Juniperus communis. Entirely white specimens (with slate grey stipes) of Mycena pseudocorticola may also be encountered (see photo below).

Go to key to sect. Supinae.