Assessment Notes

Justification

Gastroleccinum scabrosum has only been recorded from one site in North America in 1966 and two sites in Taiwan, Province of China in 1979. There are no recent records or more information on this species, and habitat preference is not yet clear. Given their presence in very distinct regions and types of habitats, specimens from Taiwan, Province of China and North America should be reviewed to confirm that they belong to the same species, and targeted search efforts are needed to estimate current population size. For now, the species is assessed as Data Deficient (DD).

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Taxonomic notes

This is the only known species in the monotypic genus Gastroleccinum. It was originally described as Gastroboletus scabrosus (Mazzer and Smith 1967), but later transferred into the new genus Gastroleccinum, in 1989 (Watling 2008).

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Geographic range

Gastrolleccinum scabrosum has been reportedly recorded in Michigan, USA (Mazzer and Smith 1967) and Taichung and Nantou in Taiwan, Province of China (Yeh and Chen 1980), but the latter requires confirmation.

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Population and Trends

Gastroleccinum scabrosum is known from only three disjunct localities, from observations made in 1966 and 1979. Since it is not particularly inconspicuous, the lack of records indicates this could be a rare species, but without more recent and targeted search efforts as well as more information on habitat preferences it is difficult to estimate the current population size.

Population Trend: Unknown

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Habitat and Ecology

Specimens were found in very distinct types of habitats in North America and Taiwan, Province of China. In North America it was found growing gregariously on sandy soils in secondary growth oak-hickory forest and assumed to be ectomycorrhizal with Quercus sp. (Mazzer and Smith, 1967, Watling, 2008), while in Taiwan, Province of China it has been found in mixed forest (alt. 3,200-3,400 m asl) and in a Sasa bamboo forest (3,000-3,200 m asl) (Yeh and Chen, 1980). More research into habitat preferences for this species is needed.

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Threats

Threats to this species are unknown.

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Conservation Actions

A taxonomic review is recommended to confirm that specimens from North America and Taiwan, Province of China belong to the same species and confirm placement in a monotypic genus, namely through the use of molecular data. Moreover, targeted search efforts and research into its habitat preferences are needed to help estimate the area of distribution and population size.

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Source and Citation

Cunha, S.P. & Gonçalves, S.C. 2025. Gastroleccinum scabrosum. The IUCN Red List of Threatened Species 2025: e.T265980182A266020470. Accessed on 23 November 2025.

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• Country occurrence