Assessment Notes

Justification

Gymnopanella nothofagi is currently known only from southern Chile, in the Aysén Region, growing on water saturated trunks in evergreen and bog forests dominated by species of Nothofagus. It likely also occurs further south in Chile, but that area has been undersampled due to the logistical difficulties in carrying out survey work in the region. Regions north of Aysén do not have the year round high precipitation that is characteristic of Aysén, and it is unlikely that the species will be found in those regions. As the forests on the Argentinian side of the mountains are drier, it unlikely occurs in that country. The species has only been recorded in nine of the over 100 sites that have been surveyed in the Aysén Region by experts in this group of fungi. Based on the limited number of sites where it has been found throughout Aysén, even including potential areas further to the south, the species is considered rare with a total population size of up to 8,000 mature individuals. As the species occurs scattered throughout its range, all of the individuals occur in one subpopulation. Threats to the species are primarily due to natural resource exploitation and development, especially construction of water reservoirs for hydroelectric power. Therefore, it is thought to be in decline, and so the species is listed as Vulnerable.

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Geographic range

The species is known from nine sites at five localities in southern Chile, in Aysén Region, at approximately 45–46° south latitude. This region belongs to the Andean Patagonian forest ecosystem. It has been collected from the following localities: Lake Yulton, El Tabo, Santa Clara lagoon, Blanco river and Riesco lake. The range of altitude of the records varies from 39 m to 555 m above sea level. Because the forests on the Argentine side of the mountains are drier, it likely does not occur there.

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Population and Trends

The species is known from the evergreen Aysén Region of southern Chile. Gymnopanella nothofagi has been recorded from nine sites within the region, all within high quality forests. The holotype was collected from Lake Yulton, growing on a fallen trunk in a Nothofagus betuloides dominated forest. Eight more collections were obtained from sites in the region, one with 20 basidiomes, seven more with fewer (12), and only one with two basidiomes. The species has not been found outside of the Aysén Region. Regions north of Aysén do not have the year round high precipitation that is characteristic of Aysén. It is unlikely that the species will be found in those regions. It may occur further south where there is a need for further surveys. The species has only been recorded in nine of the over 100 sites that have been surveyed in the Aysén Region by experts in this group of fungi. Based on the limited number of sites where it has been found throughout Aysén, even including potential areas further to the south the species is considered rare and there are up to 500 sites with suitable habitat, with approximately 4-16 mature individuals per site, for a total of up to 8,000 mature individuals. As the species occurs scattered throughout its range, all of the individuals are thought to occur in one subpopulation.

Population Trend: decreasing

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Habitat and Ecology

Gymnopanella nothofagi is a wood decomposer, always found growing on water saturated trunks in evergreen and bog forests dominated by Nothofagus betuloides, Nothofagus dombeyi, Nothofagus nitida, with Caldcluvia paniculata, and sometimes with Podocarpus nubigenus. Climatically the region has a humid climate with high rainfall throughout the year (Gajardo 1994).

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Threats

Threats to the species are primarily due to natural resource exploitation, including logging of native forest to transform them into Pine plantations, exotic species introduction, construction of water reservoirs for hydroelectric power, excessive grazing, and increased fire frequency and intensity (Pino 2009). Additionally, reduction in rainfall due to climate change is a serious problem given that this is restricted to very wet forests and that there has been a documented decrease in annual precipitation by about 40% during the last century, and summer rainfall is expected to decrease up to 50% more in the upcoming century (Gutierrez et al. 2014).

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Conservation Actions

There is a need to protect the habitat, including limiting proposed hydroelectric projects and controlling fire. Also, more surveys are needed, especially to the south of the known localities and in Argentina to further document the species geographical distribution and to better understand its population trends, ecology and possible threats.

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Use and Trade

No use or trade is known.

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Source and Citation

Calle, A., Drechsler-Santos, E.R., Kossmann, T., da Cunha, K.M., Sandoval-Leiva, P., Torres, D. & Vasco-Palacios, A.M. 2020. Gymnopanella nothofagi. The IUCN Red List of Threatened Species 2020: e.T172818020A172861302. https://dx.doi.org/10.2305/IUCN.UK.2020-2.RLTS.T172818020A172861302.en .Accessed on 12 February 2024

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• Country occurrence