Typically growing in Sphagnum, but sometimes
found in other habitats. Summer to late autumn. Generally a rare and probably a declining species due to drainage of suitable habitats. It is, at least, known from Austria, Denmark, Germany, Norway, Finland, Iceland, Poland, Sweden, Switzerland, and the Netherlands (The Global Red Fungal List Initiative 2023).
Pileus 7-12 mm across, broadly conical to parabolical, flattening with age, becoming plano-convex, with or without umbo, translucent-striate, pruinose, glabrescent, hygrophanous, dark sepia brown, often with a blackish grey centre when moist, pallescent to more greyish when drying, whitish at the margin. Flesh watery grey-brown; odour absent and taste insignificant. Lamellae 15-20 reaching the stipe, ascending or subarcuate, finally subhorizontal, broadly adnate, decurrent with a tooth, fairly thick, smooth to ribbed, dorsally intervenose with age, fairly dark grey-brown, paler with age, the edge pallid to whitish. Stipe 25-65 x 1-2 mm, hollow, equal, terete, straight to flexuous, delicately pruinose above, glabrous below, paler or darker grey-brown to more whitish grey, the base covered with few to numerous, long flexuous, whitish fibrils.
Basidia 27-35 x 7-10 µm, clavate, 4-spored. Spores 8-10.7 x 4-5.2 µm, Q 1.6-2.2, Qav ~ 1.8, elongated pip-shaped, almost cylindrical, smooth, amyloid. Cheilocystidia 15-45 x 8-17 µm, occuring mixed with basidia, clavate to subcylindrical, apically more or less strongly branched, covered with few to numerous, unevenly spaced, fairly coarse, simple to furcate, curved excrescences 2-10.5 x 1-3.5 µm. Pleurocystidia absent. Lamellar trama dextrinoid, vinescent in Melzer's reagent. Hyphae of the pileipellis 2-3.5 µm wide, more or less densely covered with simple to branched excrescences 1.8-7 x 1-2.5 µm, somewhat gelatinized. Hyphae of the cortical layer of the stipe 1.5-4 µm wide, smooth to sparsely diverticulate; terminal cells 2.5-7 µm wide, more or less densely diverticulate. Clamp connections present in all tissues.
Maas Geesteranus (1986 b) placed this species in sect. Cinerellae. It can be distinguished from M. cinerella on account of the habitat, a darker pileus, absence of a farinaceous smell, and somewhat different cheilocystidia. The rather similar M. pseudopicta has a completely different, very dry, often caclcareous habitat, the basidia are generally 2-spored, and the cheilocystidia generally have coarse to very coarse excrescences.