The species requires very old almost virgin coniferous of mixed forests with large decaying trunks of white firs and stable humid climate. Also continuity of old wood is required.

Syn:
Mycena atramentosa (Kalchbr.) Höhn.
Collybia atramentosa (Kalchbr.) Sacc.
Collybia fuliginaria (Batsch) Bres. sensu Bres.
Mycena fuliginaria (Batsch) Kühner sensu Bres.
Hydropus fuliginarius (Batsch) Singer sensu Bres.

Australian records may not be the same species.

A very rare species confined to old growth montane conifer forest, where it occurs on big strongly decayed logs of Abies, but also Picea. Threatened by decreasing numbers of its host.

Population on global scope probably decreasing, because of habitat destruction.

Saprotrophic wood inhabiting fungus growing on dead wood of conifers, mainly fir (Abies alba), less often spruce (Picea abies). It grows on rotting or decayed fallen trunks or stumps (rarely stumps), often covered with moss. It occurs mainly in various types of beech trees with the addition of fir and spruce or other woody species. In lower altitudes they are often almost pure beech forests with rare occurrence of fir or spruce, in foothills and mountains mixed forests with beech, fir, spruce and admixtures of maple and elm. Another habitat of this species is the scree forests with the occurence of fir. Rarely it could be found in the cultural spruce forest, but in an area that was also covered by mixed forests in the past. The fungus clearly prefers natural to primeval forests (in the vast majority of these are small-scale protected areas), in which there is plenty of dead wood and balanced damp mesoclimate of the forest. The findings come from the hills up to the mountain level, mostly from the foothills. In the hills, the fungus grows mainly in deep stream valleys, where the climate is colder due to the climate inversion, in higher altitudes on the slopes of hills and mountains.

Global climate change, clearing of fallen tree trunks from forest stands (eg along forest roads for human safety), forest opening due to forest management, clearcuts, bark beetle and windstorms (the species requires a stable wet microclimate), lack of fallens ar still standing old firs in many localities (young and middle-aged generations of firs are often lacking, which will in the future mean lack of substrate).

Ideally non-intervention; where this is not possible, then leaving as many fallen coniferous strains (especially fir) in place, taking care of the maximum possible integrity of the forest areas where the species occurs (avoid fragmentation by the formation of cuttings, pastures, etc.); support of young fir trees by fencing, reducing damage caused by hoofed animals.

No

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Kubicka, J. & Svrcek, M. 1955. Helmovka sazová – Mycena fuliginaria (Batsch ex Fr.) Bres. v Ceskoslovensku. Ceska Mykologia 9(1): 19-23.
Kühner, R. 1938a. Le genre Mycena. Encyclopédie Mycologique X. P. Lechevalier, Paris, 710 pp.  .
Ludwig, E. 2001. Pilzkompendium 1. Beschreibungen und Abbildungen. IHW-Verlag, Eching, 758 pp, 188 pls.  .
Wilhelm, M. 2004. Eine zufällige Partnerschaft?. Schweizerische Zeitschrift für Pilzkunde 82(3): 128-129.
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