Assessment Notes

Justification

Collybia bakerensis is a small, whitish to pinkish mushroom growing on woody debris in spring and summer, typically near melting snowbanks. It is common but easily overlooked because of its small size and cryptic fruiting habits (on the inside of bark around rotting logs and stumps, or underside of woody debris). It is presently known from 300 or more collections in western North America, many of which come from California and Oregon. Because of the widespread distribution and the absence of any documented decline, this species is assessed as Least Concern (LC).

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Taxonomic notes

Described from Mount Baker in Washington, USA by Smith (1944). According to Desjardin et al. (2015) it belongs in the genus Gymnopus, but molecular phylogenetic evidence is lacking for that placement.

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Geographic range

This species is widespread across the mountains of western North America, common in the Sierra Nevada and Cascade Range in California and Oregon, and occasional in the Washington Cascades and the Rocky Mountains.

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Population and Trends

Currently it is known from around 75 collections from approximately 45 localities in California, and 225 or more collections from elsewhere in western North America, the majority of which come from Oregon (Siegel et al. 2019, MyCoPortal 2020). There is no evidence to suggest that this species is in decline. Suitable habitat appears to be restricted to higher elevation forests with abundant large-diameter woody debris, which experience ample, persistent winter snowpack.

Population Trend: stable

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Habitat and Ecology

It can be found scattered in small clusters or solitary on rotting logs, stumps and other woody debris of conifers. It is saprotrophic, preferring fruiting on the underside/inside of bark layers around decaying stumps and fallen trunks, typically near melting snowbanks in spring and summer. Suitable habitat appears to be restricted to higher elevation forests with abundant large-diameter woody debris, which experience ample, persistent winter snowpack.

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Threats

The declining winter snowpack in the Sierra Nevada has altered the habitat in which this species occurs, however it is presently unknown if it affects this species. No data are available showing if this species needs a winter snowpack to fruit.

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Conservation Actions

No specific conservation actions are needed with regards to this species.

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Use and Trade

No use/trade is known.

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Source and Citation

Siegel, N. 2021. Collybia bakerensis. The IUCN Red List of Threatened Species 2021: e.T195923828A195928033. https://dx.doi.org/10.2305/IUCN.UK.2021-2.RLTS.T195923828A195928033.en .Downloaded on 29 September 2021

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