Basidiomata cespitose. On very rotten wood buried in sandy soil. Only known from the holotype.

Pileus 15 - 20 mm across, conical to campanulate, not infrequently with a papillate umbo, not sulcate, translucent-striate, pruinose, glabrescent, umber brown, paler at the margin. Flesh thin. Odour stated to be alkaline. Lamellae c. 16 reaching the stipe, tough, ascending, 1.5 mm broad, almost free to emarginate, whitish with a pale brownish tint, the edge convex, white. Stipe 70 - 80 x 1 mm, hollow, cartilaginous and brittle, equal, terete, flexuous, smooth, apically pruinose, glabrous farther below, yellowish brown or concolorous with the pileus, the base covered with long, coarse, whitish fibrils.

Basidia c. 27 x 10 µm, clavate, 2-spored, clampless, with plump sterigmata 7 µm long. Spores 9.8 - 11.6 x 6.3 - 8 µm, pip-shaped, smooth, amyloid. Cheilocystidia 27 - 54 x 11 - 13.5 µm, forming a sterile band (lamellar edge homogeneous), clavate (although frequently rather more fusiform on account of the broad base of the neck), more rarely subcylindrical, clampless, towards the middle of the lamella passing into a broad, bifurcate neck, near the pileus margin with several bifurcate or branched necks or densely covered with numerous coarse excrescences 11 - 27 x 2.5 - 7 µm. Pleurocystidia absent. Lamellar trama brownish vinescent in Melzer's reagent. Hyphae of the pileipellis 2.7 - 5.8 µm wide, clampless, covered with warts 1.8 - 3.5 x 1.5 - 2.5 µm and warted excrescences 6.5 - 30 x 1.5 - 2.5 µm. Hyphae of the cortical layer of the stipe 1.3 - 2.5 µm wide, clampless, sparsely covered with simple, cylindrical excrescences 0.9 - 4.5 x 0.9 - 2 µm, with rare terminal cells which are 2.5 - 3.5 µm broad and fairly coarsely diverticulate.

ØSTFOLD:
SKJEBERG, Høysand, 30 May 1982, Ø. Weholt M3/82 (Holotype) (L)

The entire description has been taken from Maas Geesteranus (1995).

Mycena dicranolophus belongs to section Mycena, where it comes close to M. hemispherica Peck and M. galericulata (Scop) Gray, but according to the author they should be distinguishable on account of the more numerous and broader lamellae and the shape of the cheilocystidia. In my opinion, the cheilocystidia, as they are shown in the author´s figures, seem to fit well within the variation of M. galericulata. Unfortunately, an attempt in 2022 to get an ITS sequence from the holotype, kindly put to our disposal by the herbarium in Leiden, did not succeed.