Assessment Notes

Justification

This species has been described from decaying wood of Araucaria araucana. It is the only known host, and so would be limited by its very small, and severely fragmented range (<500 km²). Therefore, this species is listed as Endangered, but we recommend further research to confirm host specificity.

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Geographic range

It is known only from one locality in Argentina, (Neuquén, Villa Pehuenia; Pérez Gorjón et al. 2012). The range of the known host is 392.51 km² (Premoli et al. 2013). The occupied area of this species is estimated as lower since it has been recorded only in the most humid area of the host range. Even though the species has been recorded in only one locality, the potential area of occupancy (AOO) per IUCN guidelines is assessed as <500 km², and severely fragmented.

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Population and Trends

The population is assumed to be declining, as although the species is known from only one locality, there has been a decline in its host's range and a decline in the habitat quality (Premoli et al. 2013).

Population Trend: Decreasing

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Habitat and Ecology

This species has been found fruiting sparsely on decayed wood of Araucaria araucana in mixed forests of A. araucana and Nothofagus spp.

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Threats

The main threat to this species is the decline of it host and habitat. Its host, Araucaria araucana, is classified as Endangered due to the decline of its population, the decrease of its AOO, the severe fragmentation and declining habitat quality. The threats impacting A. araucana in particular are from agriculture, cattle farming, logging and increases in fire frequency. All these problems negatively affect this fungal species since A. araucana is its only known host.

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Conservation Actions

Protection of the species' host and habitat is needed as well as habitat restoration. Research into the full geographic range needs to be conducted, focusing in particular on all areas occupied by its host, Araucaria araucana. Such studies could also help to estimate the population size and potential rate of decline. Research into host specificity would be useful to confirm whether it only grows on A. araucana.

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Use and Trade

There is no use/trade of this species.

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Source and Citation

Greslebin, A., Kuhar, F., Pfister, D. & Truong, C. 2020. Athelopsis tenuicystidiata. The IUCN Red List of Threatened Species 2020: e.T172733071A172861062. Accessed on 26 November 2025.

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• Country occurrence