Assessment Notes

Justification

This species is currently only known from Nahuel Huapi National Park and its surroundings in Rio Negro province, Argentina, where it is rare. Extensive surveys elsewhere in northern Patagonia have failed to find this species. Even assuming that it could occupy an area five times greater than currently known, the overall population size is estimated to be <50 mature individuals. Therefore, this species is listed as Critically Endangered.

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Taxonomic notes

Kraisitudomsook et al. (2020) examined a specimen from the Farlow Herbarium (FH-00284257, near Concepción, Chile, 1906) that was morphologically similar to Geomorium gamundiae, but with different spore dimensions and ornaments. This variability suggests that further collecting in the northern ranges of Nothofagaceae in South America may reveal additional new truffle-like species.

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Geographic range

Geomorium gamudiae has a restricted distribution with only three localities known so far from the Nahuel Huapi National Park and surroundings (Rio Negro province in Argentina).

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Population and Trends

So far Geomorium gamundiae is only known from three localities in Nothofagus forest from the Nahuel Huapi National Park and surroundings (Rio Negro province). This hypogeous species may be easily overlooked but, based on extensive surveys in northern Patagonia, the collections seem to indicate that it has a restricted distribution. Although the distribution of the species could extend further south, it is probably not present in southern Patagonia (Magallanes and Tierra del Fuego) where surveys of hypogeous fungi have been quite extensive. Conservatively assuming that there could be 2-3 mature individuals per site, and that the potential range could be five times greater than its current known range, the overall population size estimate is still extremely small (30-45 mature individuals). The scattered collections over the years (2001, 2012, 2017) seem to indicate that the population is stable in the area.

Population Trend: stable

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Habitat and Ecology

This hypogeous, ectomycorrhizal species associates exclusively with Nothofagus species in Patagonia. So far it has been found in association with Nothofagus pumilio and Nothofagus dombeyi.

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Threats

This species is associated with an increasingly threatened Nothofagus forest. Forest fires (intentional and accidental due to drought and climate change) as well as human activities in the area (tourism, logging) are a growing threat. The known distribution is also very close to Bariloche, and so urban expansion could be impacting this species.

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Conservation Actions

One of the known localities of Geomorium gamundiae lies within the protected area of the Nahuel Huapi National Park. Education about protecting fungi is recommended. Further research is needed to assess the distribution and population number of G. gamundiae in adjacent areas to its known sites, especially in Chile. Since it is a hypogeous fungus, knowledge about fruiting patterns, dispersal and host-specificity of the species could be beneficial for its conservation.

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Use and Trade

No use or trade are known so far.

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Source and Citation

Kuhar, F., Monroy Guzmán, C., Pfister, D. & Truong, C. 2020. Geomorium gamundiae. The IUCN Red List of Threatened Species 2020: e.T172735597A172861127. https://dx.doi.org/10.2305/IUCN.UK.2020-2.RLTS.T172735597A172861127.en .Accessed on 1 February 2024

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• Country occurrence