Assessment Notes

Justification

Pseudoaustroboletus valens is a bolete found in East Asia, Southeast Asia, and the United States of America, with a population size estimated to be in the tens of thousands of mature individuals. Deforestation in Southeast Asia is likely leading to a decline in population in part of its range, but since the species is not exclusive to this region and given the large amount of potential habitat, P. valens is assessed as Least Concern (LC).

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Taxonomic notes

Pseudoaustroboletus valens is the only species in its monotypic genus, created based on morphological and molecular data for this species (Li et al. 2014).

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Geographic range

Pseudaustroboletus valens is known from East Asia and Southeast Asia, specifically China, Japan, Indonesia (not mapped), Malaysia (both Peninsular Malaysia and Borneo), Singapore and Vietnam. The species has also been found in the United States of America and though the most recent confirmed record was in 1947 (GBIF.org 2023), a more recent observation in Mushroom Observer in 2001 (Mushroom Observer 2017) could indicate that this species is still present in this region.

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Population and Trends

Pseudoaustroboletus valens has a wide distribution, especially in East and Southeast Asia. It has been recorded in approximately 43 sites in total, in Japan (27), China (five), Malaysia (four), USA (three), Singapore (two), Indonesia (one) and Vietnam (one) (Li et al. 2014, Pham and Morozova 2020, GBIF.org 2023). The population size is estimated to be in the tens of thousands of mature individuals, using the guidelines in Dahlberg and Mueller (2011). However, some observations made in Indonesia, Singapore and the USA are more than 50 years old. Given that its fruitbodies are not inconspicuous, this could indicate that the species is not common, in at least part of its range. Deforestation in Southeast Asia may be causing a decline in population size for this species. However, the total population reduction is difficult to estimate given that P. valens is not exclusive to this region and has a large potential area of suitable habitat.

Population Trend: Decreasing

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Habitat and Ecology

Pseudoaustroboletus valens is a terrestrial fungus, found in forests dominated by Fagaceae (Li et al. 2014).

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Threats

The extensive deforestation for agricultural practices in Southeast Asia (World Resources Institute 2023) may present a threat to this species and cause a decline in population in part of its range.

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Conservation Actions

Though the species is not considered threatened, habitat protection in Southeast Asia is recommended to prevent further population declines in this region. Attempts to register this species in its natural conditions are needed to better understand its ecology and estimate its distribution and population size. A taxonomic review to confirm its placement in a monotypic genus is also recommended.

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Source and Citation

Cunha, S.P. & Gonçalves, S.C. 2025. Pseudoaustroboletus valens. The IUCN Red List of Threatened Species 2025: e.T265999779A266019545. Accessed on 22 November 2025.

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• Country occurrence