Assessment Notes

Justification

Amanita magniverrucata is a locally common and widespread species in western North America. The population appears stable, although this may change in future should reductions in rainfall adversely impact it or its host species. It is assessed as Least Concern (LC).

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Taxonomic notes

Described from California, USA (Thiers and Ammirati 1982).

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Geographic range

This species occurs in coastal California, from San Diego County north into Mendocino County, and in the Sierra Nevada foothills; also in the southern California mountains, and the sky islands in Arizona. It has been reported from single collections from Oregon (Tulloss 2021), and Washington (Mycoportal 2021) but little information is available regarding this collections. It is likely also in northern Baja California, Mexico.

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Population and Trends

The population is widespread, and locally common. It occurs in young to mature forests, especially with oaks (Quercus spp.). No decline has been noted.

Population Trend: stable

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Habitat and Ecology

It is ectomycorrhizal with oaks (Quercus spp.), especially with Coast Live Oak (Quercus agrifolia) in southern and central California. It also occurs with Bishop Pine (Pinus muricata) and possibly with other conifers, in young to mature forests.

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Threats

Climate change, specifically a reduction of precipitation in southern California could pose a threat.

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Conservation Actions

No specific conservation actions are needed with regards to this species. Research is needed on population trends. Although no decline has been noted, a lot of the population occurs in areas with a changing climate, and overall drying of habitat in southern California.

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Use and Trade

No use/trade is known.

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Source and Citation

Siegel, N. 2021. Amanita magniverrucata. The IUCN Red List of Threatened Species 2021: e.T195921722A195926244. https://dx.doi.org/10.2305/IUCN.UK.2021-2.RLTS.T195921722A195926244.en .Accessed on 25 September 2024

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• Country occurrence