Assessment Notes

Justification

Cortinarius magnivelatus is a medium-sized mushroom with a stout stature, and hypogeous fruiting habit (typically fruiting under the duff). It is recognizable by its white to whitish-tan cap, a persistent white partial veil of thick, radially fibrillose membrane that remains mostly unbroken even in age, and rusty brown spores. It is currently known from over 100 records from around fifty localities in California, Oregon, and Nevada, USA, and is believed to be under-reported. In combination with the lack of evidence for any recorded decline, this species is assessed as Least Concern (LC).

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Taxonomic notes

This species was described as Pholiota magnivelata (Morse 1941), from a collection made at “General Grant National Park” (now Kings Canyon National Park), California, USA. It was invalidly transferred into the genus Cortinarius by Thiers and Smith (1969), but the transfer was subsequently made correctly by Fogel (1994).

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Geographic range

This species is widespread in the Sierra Nevada, and southern Cascade Range in California and Oregon, and from two high elevation locations in eastern Nevada.

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Population and Trends

The population is widespread, and no decline has been noted. It is currently known from over 100 records from around fifty localities in California, Oregon, and Nevada, USA, and is likely to be under-reported.

Population Trend: stable

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Habitat and Ecology

It is solitary, scattered, or found in small clusters under duff or in soil. Typically it forms ‘shrumps’ (pushing up mounds of duff), rarely becoming exposed, or only breaking the surface in areas with hard-packed ground and/or a thin duff layer. It is ectomycorrhizal with conifers, likely primarily associated with fir (Abies spp). This species does not appear to be restricted to mature forest, and has been found fruiting after heavy logging disturbance. Fruiting is in late spring and summer.

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Threats

No specific threats have been identified with regards to this species.

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Conservation Actions

No specific conservation actions are needed with regards to this species. Additional research into range of this species would be useful, e.g. does in occur into the Blue Mountains of Oregon, or the Rocky Mountains.

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Use and Trade

No use/trade is known.

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Source and Citation

Siegel, N. 2021. Cortinarius magnivelatus. The IUCN Red List of Threatened Species 2021: e.T198477888A198489654. https://dx.doi.org/10.2305/IUCN.UK.2021-2.RLTS.T198477888A198489654.en .Accessed on 5 October 2022

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• Country occurrence