Lyophyllum favrei is a conspicuously brightly-coloured and rare litter-inhabiting species characteristically found in beech (Fagus) woodland and old alluvial forest habitats in central Europe. The distribution has outliers in Greece, SW Russia, Spain and the UK. It has relatively few known European sites (ca. 50) with a clear stronghold of ca. 32 sites in Switzerland where it is considered to be moderately threatened and showing some decline due to river management. Elsewhere in Europe, there are very few (>5) sites per country where it is vulnerable to destruction by chance or accidental (stochastic) events, for example, severe storm damage or site management operations.

Switzerland has been well-surveyed and further discoveries of new sites are expected to be few in number. Even when unknown sites are considered, it is expected that Switzerland will remain the global stronghold for this species. The Swiss sites are localised in a series of river catchments and it is nationally assessed as fragmented and declining. Each catchment is assumed to hold a subpopulation. Applying Criterion C with an estimated global total of mature individuals not exceeding 2500, an inferred continuing decline in habitat extent/quality and with no subpopulation exceeding 250 mature individuals, this species is assessed as EN C2a(i).

 

Based on molecular analysis (Hofstetter et al. 2002) and taking account of Redhead et al.‘s (2006) proposal to conserve the name Lyophyllum with a different type, Calocybe favrei should be adopted as the current name for this species.
Lyophyllum favrei f. ochracea is excluded from this assessment as this is now recognised as a species in its own right, L. ochraceum or, preferably, Calocybe ochracea.

Anders to Martyn and Beatrice (now answered below): It is assessed as VU in Swiss, How many unrecorded sites should we consider in Europe (which will affect the estimated total population size). If we tentatively assume 2 mycelial genotypes to occur at each location (assuming corresponding to 20 mat individuals) , with in total less than 125 locations, the no of mature ind would be less than 2500 - then EN. If more than 125 sites - rather VU. 

Beatrice: In my opinion the assumption of 2 genotypes per site is already rather optimistic. There are not many stations known with 20 mature individuals. Therefore EN seems to be ok -it may remain VU in Switzerland.

Martyn15Apr2021:
The Swiss stronghold has 32 known sites which, if we assume each site has 2 genets and therefore 20 mature individuals, equates to 640 mature individuals. Given the intensive surveying that has occurred in Switzerland, Beatrice thinks it unlikely that many new sites remain to be discovered. If we estimate a maximum of 10 undiscovered Swiss sites, this yields an additional 200 individuals (840 in total). This stronghold population is partitioned in numerous river valleys, each of which is assumed to be a subpopulation comprising fewer than 250 individuals.
18 sites are known from other countries, but with no country having over 5 sites. 18 sites equates to 360 individuals. As this species forms such highly conspicuous mushrooms, it seems reasonable to estimate that there may be x3 sites (a generous estimate) if all were known (1080 individuals extant in other countries). Grand total: ca. 2000 mature individuals. With an inferred continuing decline (habitat), this would qualify C. favrei for EN C2a(i)

Calocybe (Lyophyllum) favrei is an European species mainly found across central Europe from Spain to Russia. It has relatively few European sites (50 known) with a continental and global stronghold of ca. 32 sites in Switzerland. The maximum number of known sites in any other country is 4.

The number of sites known after in Europe are; Austria 2 in Klagenfurt & Kirchdorf; Croatia 1 in Ravna Gora; France 3 with one in a protected area; Germany 2 incl. Starnberg; Greece 1; Rep. of Ireland: 1 but pre-1980 (Fraiture & Otto 2015); Italy 4; Russia 1 in SW Russia (probably Adygea or Karachaevo-Cherkesia); Spain 2 in Catalonia and the Basque Country; Switzerland ca.32 sites exclusively in the north of the country on the banks of alpine rivers; UK: 1 woodland site with 2 potentially extant fruiting patches (but no sightings since 1987); Ukraine 1 in Crimea (Yalta Mountain Forest Nature Reserve) in 1992 (Moser 1993)

In Switzerland, it is nationally red-listed as VU (Vulnerable, B1ab(iii)) based on limited extent of occurrence, severely fragmented population and with some decline due to river management. Elsewhere in Europe, there are very few (<5) sites per country where it is vulnerable to destruction by chance or accident (stochastic events). For example, one fruiting patch in the UK was chosen as the site for a site-management bonfire (Legon 1989a,b) and no further fruiting has been observed there. The other UK fruiting patch (both are in the same woodland) has been similarly unproductive since the highly damaging “Great Storm” of 1987 which uprooted many beeches in the area. Therefore, although increased survey intensity is likely to yield a modest number of new records, it is expected that national populations are more or less stable or in decline.

On average, each site is assumed to hold 2 genets which, for a litter-inhabiting fungus, is assumed to equate to 20 mature individuals (Dahlberg & Mueller, 2001). Switzerland has been very well surveyed for this species and only an estimated additional 10 sites is stimated remain to be found. This would give a total of 42 sites and 840 mature individuals, and each site could be a distinct subpopulation here, as records are restricted to river valleys. Elsewhere there are 18 known sites and it is assumed that the true number of sites could be three times higher. This would give 54 sites and 1080 individuals. The global total would then be (1080+840) ca. 2000 mature individuals. The total population is inferred to have an continuing decline due to an inferred continuing decline of extent and quality of its habitat.

Lyophyllum favrei is a litter-inhabiting, saprotrophic species of broadleaved, mainly Fagus, woodland that may fruit, sometimes in abundance, over many years (decades) at the same spot as the mycelia can be longlived if the habitat remain undisturbed. In the Switzerland stronghold and elsewhere it grows in old alluvial forest sites, often in river valleys and often on calcareous soil.

Habitat destruction (man-made and storm/flood damage), unsympathetic river bank and forest management, tourism (excessive trampling of alluvial forest soils). The English woodland site receives indirect protection as a statutory Site of Special Scientific Interest, but C. favrei does not receive direct protection as it is not listed as one of the elements contributing to the site’s special scientific interest. The two areas of this woodland known to have been occupied by C. favrei since 1970 have both been damaged; one by inappropriate siting of a management bonfire and the other by a severe storm in 1987. In view of the increasing incidence of extreme weather events, there is likely to be an increasing potential threat from windthrow of Fagus trees causing mycelial damage and death.

Exact positions of fruiting patches to be plotted on site managers’ maps and referred to when forest or river management work is being planned to ensure that areas with fruiting populations of this fungus are taken into account and not damaged. Protection of all fruiting sites is required. Site information should be passed to local authorities.

Population structure should be investigated and environmental samples from areas formerly supporting fruiting should be probed for species-specific DNA markers (molecular ecology) to see if fungus is still present in those areas in a non-fruiting (mycelial) state. Further research needed to establish population extent and trends in countries which have been surveyed less intensively for this species. Research required to include this fungus within site-based management planning.

No known uses or trade.

Dahlberg A. & Croneborg H (2006). 33 threatened fungi in Europe. ECCF
DAhlberg A & Mueller G 2011.
ESCÀNEZ, Ll.; (2010); Calocybe favrei (R. Haller Aar. & R. Haller Suhr) Bon, novetat pel catàleg de la Flora Micològica del Berguedà.; MOIXERÓ. Fongs i Flora del Pirineu, 1:
Escanez Monferrer Ll. (2011) Calocybe favrei (R. Haller Aar. & R. Haller Suhr) Bon. Bolets de Catalunya, de la Peninsula ibèrica I de las Illes Balears : lam. 1458. Societat Catalana de Micologia
Evans S., Henrici, A. & Ing, B. 2006. Red data list of threatened British fungi (preliminary assessment) http://www.fieldmycology.net/Download/RDL_of_ Threatened_ British_ Fungi.pdf
Hofstetter, V., Clémençon, H., Vilgalys, R. & Moncalvo, J.-M. (2002). Phylogenetic analyses of the Lyophylleae (Agaricales, Basidiomycota) based on nuclear and mitochondrial rDNA sequences. Mycol. Res. 106(9): 1043–1059
Legon, N.W. (1989a) Profiles of Fungi 21-22. Mycologist 3(3): 142
Legon, N.W. (1989b) Fungi from Norbury Park, Surrey, 1984–88. Mycologist 3(3): 131–132
Moser M. 1993. Remarkable species of Agaricales collected in the Crimean Mountains (Ukraine). – Ukrainian Botanical Journal. – 50 (4): 93-103.
Redhead, S.A., Hofstetter, V., Clémençon, H., Moncalvo, J.-M. & Vilgalys, R. (2006). Proposal to conserve the name Lyophyllum with a conserved type (Basidiomycota). Taxon 55(4): 1034–1036.
Reid D.A. 1958. New or interesting records of British Hymenomycetes II. Transactions of the British Mycological Society 41(4): 419–445.
Senn-Irlet B. (2012) http://www.wsl.ch/dienstleistungen/publikationen/pdf/12111.pdf
Senn-Irlet, B. (2012) Merkblatt Pilze: Karminschwärzling.Lyophyl-lum favrei R. Haller und R. Haller. [published online October 2012]. Available from: http://www.wsl.ch/merkblaetter_pilze Birmens dorf, Eidg. Forschungs anstalt WSL. 2 S