Assessment Notes

Justification

Ramaria verlotensis is a rare ectomycorrhizal fungus, endemic to the Pacific Northwest of North America and restricted to old-growth conifer forests. Despite extensive survey efforts under the Northwest Forest Plan since 1998, it is only known from four sites. The old growth forest habitat has become very rare due to timber logging during the last century, and the habitat is assessed as still declining.(>30% population reduction in the past 50 years; i.e. three generations, based on >90% loss of old growth forest in the last 100 years). All the sites where this species occurs contain considerably less than 250 mature individuals, and though the present sites are protected, the future of the habitat is insecure. It is assessed as Endangered (EN) under criteria C1 and C2a(i).

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Taxonomic notes

Described by Marr and Stuntz in 1973, based on a collection made in 1969 from the North Cascades in Washington, USA.

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Geographic range

Only known from four disjunct populations in North Western USA. Two are from the Cascade range in Washington, a site in the Rocky Mountains in Idaho, and a site on the far northern coast of California.

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Population and Trends

Ramaria verlotensis is a rare fungus, endemic to the Pacific Northwest of North America. It is characteristic for old-growth forests where it forms ectomycorrhiza with Abies spp., Pseudotsuga menziesii, and Tsuga heterophylla. It is only known from 4 sites. This species is a very rare and has been extensively searched for under the Northwest Forest Plan since 1998 (Castellano et al. 1999); despite these intensive survey efforts, the number of known sites has not increased. Described from a collection made in 1967 from the North Cascades in Washington, a single collection made in Idaho in 1982, and a single collection from northern California was reported (Castellano et al. 1999). It has also been found at Mount Rainier (Efren Cazares, personal communication). It is confined to old-growth conifer forests. The old growth forest habitat has become very rare due to timber logging during the last century, and the habitat is assessed as still declining. The population of R. verlotensis is estimated to have been reduced by >60% in the past 100 years based on >90% loss of old growth forest. For the purposes of Criterion A of IUCN Red List assessments, population declines of Ectomycorrhizal fungi are assessed over 50 years (corresponding to three generations (Dahlberg and Mueller 2011). The decline of R. verlotensis during the last 50 years is estimated to exceed 30% and to be ongoing at a lower rate. The total number of locations, considering unrecorded ones, is not considered to exceed 100 and the total number of mature individuals to be less than 2500 mature individuals. Though the present known sites are protected, the future of unrecorded localities and the habitat is insecure.

Population Trend: unknown

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Habitat and Ecology

It is an ectomycorrhizal terrestrial fungus confined to old-growth mature forests where it forms ectomycorrhiza with Abies spp., Pseudotsuga menziesii, and Tsuga heterophylla. Ectomycorrhizal fungal mycelia are perennial and may live for several decades and potentially much more than a century with a continuous presence of living trees and presence of an old-growth habitat.

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Threats

This is an ectomycorrhizal fungus species dependent on living host trees for viability. The major threat to this species and its co-occurring co-generic brethren is habitat destruction, viz. the logging of old-growth forests to which it is confined. The extent of old growth forest in the Pacific Northwest of North America has declined 90% in the last century (Society of American Foresters 1984, Haynes 1986).

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Conservation Actions

Habitat protection: the type location is an old campground, with recreation activities in the area. Two sites (Mount Rainier, WA and Jedediah Smith State Park, CA) are protected in National and State parks. The exact location of the Idaho site is unknown. Any new sites should be protected from logging and other disturbances. This species is a so-called Strategy 1 species under the Northwest Forest Plan (Castellano et al. 1999), and has been surveyed and managed within the range of the Northern Spotted Owl (Strix occidentalis caurina).

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Use and Trade

None known. Similar Ramaria are edible and are collected for consumption.

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Source and Citation

Siegel, N. 2019. Ramaria verlotensis. The IUCN Red List of Threatened Species 2019: e.T125433300A125433305. https://dx.doi.org/10.2305/IUCN.UK.2019-1.RLTS.T125433300A125433305.en .Accessed on 13 February 2024

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• Country occurrence