Assessment Notes

Justification

Craterellus convolvulatus is a species of fungus found growing in oak woodland in North America. While it could, potentially, be widespread, in parts of its putative range it has not been reported for decades. This could potentially suggest either a highly fragmented population or an unexplained rapid decline. Therefore, it is not possible to accurately estimate the extinction risk and it could theoretically fall into any category from Least Concern to Critically Endangered. Thus, C. convolvulatus is assessed as Data Deficient.

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Geographic range

Described from oak woodland in Michigan, United States of America (see Buyck et al. 2010), it has also been noted in Indiana (Bates et al. 2017). It is presumed that the species could occur throughout oak woodland in the Midwestern United States although it hasn't been reported during 30 years of extensive survey work in northeastern Illinois-northwestern Indiana (G. Mueller pers. comm. 2024). It has been noted from oak woodland in Chiapas, Mexico (Ruan-Soto et al. 2021), however, given the great distance between these regions, its presence in Mexico is considered uncertain awaiting genetic analysis.

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Population and Trends

The overall population size and trend are unknown. It is considered gregarious (see Buyck et al. 2010), but the lack of any collections in part of its potential range where there has been intensive surveying make it difficult to accurately estimate the population parameters.

Population Trend: Unknown

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Habitat and Ecology

This is a species of oak woodland, described from a collection made on the edge of a bog (see Buyck et al. 2010).

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Threats

Further research is required to ascertain whether it faces any threats or not.

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Conservation Actions

Some genetic studies into the collections made in Mexico would be useful to ascertain whether this does truly represent this species, or if it could be another, as yet undescribed taxon. Research should also investigate any potential threats that may exist, and explain the paucity of records in some areas.

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Use and Trade

It could be considered to be edible (Ruan-Soto et al. 2021), but this is based on information from outside of the range that is included in the assessment, so is only tentatively mentioned here.

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Source and Citation

Westrip, J.R.S. 2025. Craterellus convolvulatus. The IUCN Red List of Threatened Species 2025: e.T269707349A269707351. Accessed on 23 November 2025.

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• Country occurrence