European endemic, restricted distribution, only recorded in Finland, Norway, Sweden and UK, red-listed in all these countries, restricted microhabitat, populations are confined to relatively isolated microsites.
Preliminary global (and European) red-list assessment: VU B2ab(ii,iii,iv,v); C2a (i) (Vulnerable).
A -criterion. Sufficient population/habitat decline not met
Length of evaluation period: 20 years (=3 generations according to recommendations of Dahlberg & Mueller 2011).
B criterion: AOO < 2000 km2
C-criterion: <10,000 ind. and less than 1,000 ind/subpopulation
Each mosspatch with mycelium is considered as one mature individual. Sweden estimated to have 5000 functional mature individuals (MI), UK 320-1000 MI, Norway 360 FMI and, Finland 200 MI.
D-criterion: too many mature individuals
Mainly occurring in stable and not threatened habitats However, the total population is estimated to slowly decline as a consequence of habitat over growth and exploitation. Sensitive for trampling. Assessed as nationally declining in Fin, No and Swe.
Northern Europe (UK distribution is restricted to Scotland)
European population in three of four occupied countries apparently declining
Population Trend: Deteriorating
Confined to relatively isolated microsites comprising moss-colonised calcareous and/or base-rich rocks and boulders.
In Scotland, the major threat is cessation of grazing leading to colonisation and shading of site by Betula saplings. The overwhelming majority of the known world population is currently in Sweden where it mainly is growing in stable not endangered habitats. The total population of the country is, however overall decrease slightly, due increasing shading of sites as a consequence of ceased grazing and exploitation through construction. The species is also sensitive to trampling wear along paths and trails on the moss -covered limestone outcrops.
Cutting and stump treatment of invasive Betula
Population genetical investigation of physical extent of genets (and how many ramets per genet) would improve estimates of “mature individuals”
Fleming, L.V., Ing, B. & Scouller, C.E.K. 1998. Current status and phenology of fruiting in Scotland of the endangered fungus Tulostoma niveum. Mycologist 12(3): 126-131.
Holden, E.M. (2011). Baseline data to indicate the extent of the white stalkball (Tulostoma niveum) on Craig Leek Site of Special Scientific Interest. Scottish Natural
Heritage Commissioned Report No. 177
Jeppson M. 2005. Åtgärdsprogram för bevarande av vit stjälkröksvamp (Tulostoma niveum). (Species Action Program for Tulostoma niveum, In Swedish with English summary). Naturvårdsverket, report 5512. Can be downloaded through internet.
Jeppson, M. 2006. Tulostoma niveum - en av världens sällsyntaste svampar [Tulostoma niveum - one of the rarest fungi in the world]. Svensk Mykologisk Tidskrift 27(2): 58-63.
Jordal J.B. & Johnsen J.I. (2009) Hvit styltesopp Tulostoma niveum - nå også på Sørvestlandet. Agarica 28: 64-70 [http://www.jbjordal.no/publikasjoner/Tulostoma_niveumAgarica-28.pdf].
Kers, L.E. 1978. Tulostoma niveum sp. nov. (Gasteromycetes), described from Sweden. Botaniska Notiser 131: 411-417.
Lost & Found Fungi Project website: http://fungi.myspecies.info/content/lost-found-fungi-project (accessed 22Feb2017)