Assessment Notes

Justification

This species is only known from two very disjunct areas (Magallanes Nacional Reserve, Chile, and Nahuel Huapi National Park, Argentina). This wide geographic range could indicate that the species has been overlooked in the past, particularly because detailed analysis may be required to differentiate between this and Geomorium singeri. Without further information to tell whether this species is more evenly spread throughout Patagonia, or if it truly has this fragmented distribution it is not possible to estimate the population size or its trends. As such it could potentially fall in any category between Critically Endangered and Least Concern. Therefore, this species is listed as Data Deficient.

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Taxonomic notes

Kraisitudomsook et al. (2020) mention that this species could correspond to Underwoodia singeri var. fulvostipitata, but the type specimen of this variety is apparently lost.

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Geographic range

This species occurs in Nothofagus forests of southern (two localities in Magallanes Nacional Reserve, Chile) and northern (one locality in Nahuel Huapi National Park, Argentina) Patagonia. The wide geographic distance between these localities may indicate that the species is overlooked, or it could be confused with Geomorium singeri.

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Population and Trends

So far this species is only known from two localities in southern Patagonia (Magallanes Nacional Reserve in Chile) and one locality in northern Patagonia (Nahuel Huapi National Park in Argentina). The wide geographic distance between these localities may indicate that the species is overlooked. Geomorium geodon is also easily confused with the more common species Geomorium singeri, but this assumption may be the result of the timing of sampling and the locations visited (Kraisitudomsook et al. 2020). The species is probably not frequent and its distribution scattered, but based on the uncertainty of its occurrence over its distribution range, it is not possible to define population number and AOO.

Population Trend: unknown

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Habitat and Ecology

This ectomycorrhizal species associates exclusively with Nothofagus species in Patagonia. So far it has been found in association with Nothofagus pumilio (Magallanes Forest Reserve in Chile) and Nothofagus dombeyi (Nahuel Huapi National Park in Argentina).

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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), cattle and volcanic activity in the northern part of its distribution range are a growing threat.

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Conservation Actions

The three known localities of Geomorium geodon are within protected areas (national park or national reserve) in both Chile and Argentina. Measures to control cattle (at least inside of protected areas) would probably benefit this species. Further surveys are needed to find out whether the species is overlooked or the populations are truly fragmented, making sure it is carefully identified with detailed analysis to separate individuals of this species and Geomorium singeri. Knowledge about its habitat requirements and host specificity would be beneficial to assess its conservation status.

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Use and Trade

No uses or trade are known so far.

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Source and Citation

Kuhar, F., Monroy Guzmán, C., Pfister, D. & Truong, C. 2020. Geomorium geodon. The IUCN Red List of Threatened Species 2020: e.T172735667A172861132. https://dx.doi.org/10.2305/IUCN.UK.2020-2.RLTS.T172735667A172861132.en .Accessed on 10 February 2024

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• Country occurrence