Assessment Notes

Justification

This species has a very restricted range, and is known from only one locality. This site is under protection and no declines are currently known, but the situation should be carefully monitored. The overall population size is estimated to be very small, with a maximum of 200 mature individuals, but a more likely estimate of only 30 mature individuals. Therefore, this species is precautionarily assessed as Critically Endangered under criterion D.

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Geographic range

It is known only from one locality in Neuquén, Argentina (Nahuel Huapi National Park at Puerto Blest). It has been searched for but not found in Chile (Gorjón and Hallenberg 2012).

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Population and Trends

The population trend is unknown, but it is possibly decreasing. The species is known from one location. There are probably only 100 trees that this species could occur on in this area, and out of c. 20 trees that have been checked it has been found on three. Therefore, assuming there are two mature individuals per tree, the overall population size is likely to be c. 30 mature individuals (maximum 200).

Population Trend: Unknown

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Habitat and Ecology

This species grows on bark of living Saxegothaea conspicua. The only location where this species has been found is very humid.

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Threats

In Argentina, the host of this species, Saxegothaea conspicua is restricted in distribution and confined to national parks. In Chile, conversion of native forest in the coastal Cordillera to commercial plantations of Pinus radiata and Eucalyptus, means that much of the potential habitat for Saxegothaea conspicua has been lost and continues to disappear, but Aleurodiscus stratosus has not been recorded from Chile. Where A. stratosus itself is known to occur, it is fairly well protected, although tourism could be an issue.

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Conservation Actions

It is necessary to protect the only known host of this species and its habitat. Education and awareness initiatives in the area could minimise impacts on the species from tourism. The potential for this species' presence in Chile needs to be assessed. Knowledge of factors affecting its limited distribution within the host range are needed. Work to understand the best management practices for the host species would be useful. Research into the taxonomy, population size, distribution and trends of this species and its host would be useful too.

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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. Aleurodiscus stratosus. The IUCN Red List of Threatened Species 2020: e.T172732651A172861057. Accessed on 22 November 2025.

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• Country occurrence