Assessment Notes

Justification

This species is known only from its type locality within the Brazilian Amazon forest, near the border with Peru. It was collected more than 120 years ago and never found again. Despite the lack of data to infer its potential occurrence range, it is possible that the species only occurs in the Amazon region, since it has not been found in other Brazilian phytogeographical domains with higher sampling efforts, such as the Atlantic Forest. The species’ shortage of records, lack of sampling efforts in its type locality, and lack of distribution data hinder understanding of its potential distribution, population size, ecology and niche requirements. More efforts are required to understand the species’ needs, past and current trends, threats and taxonomy. Therefore, Cantharellus helvelloideus is assessed as Data Deficient.

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Taxonomic notes

The taxonomic status and placement of this species is unclear.

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Geographic range

Cantharellus helvelloideus is known only from its type locality within the Brazilian Amazon forest, in the vicinities of Juruá-Mirim river, Acre state, near the border with Peru. The species’ shortage of records, considering that it was collected only once in 1901, described in 1904, and never found again, hinders the understanding of its potential occurrence area. Nevertheless, it is possible that the species may occur within the Amazon in similar habitats.

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Population and Trends

The species is currently only known from its holotype, registered in Acre state, Brazil, near Juruá-Mirim river, at the border with Peru, in the Brazilian Amazon forest. The species' type locality currently represents a large sampling gap for fungi, which can contribute to the apparent rarity of the species, where since its description 120 years ago, it has never been registered again. Nevertheless, the species has never been found in other Brazilian phytogeographical domains that are historically more well sampled, such as the northern and southern Atlantic Forest, nor near Manaus which is also a well-sampled area, indicating that the species can be restricted to the Amazon. Considering this, with currently available data, it is not possible to estimate population parameters or understand the species’ niche requirements to reasonably infer its potential area of occurrence.

Population Trend: Unknown

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Habitat and Ecology

Despite it only being known from its type locality near the Peruvian border, it is possible that the species occurs along the Amazon in sites where its specific biotic and abiotic requirements are met.

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Threats

The lack of data regarding the species' distribution, habitat requirements, and population trends hinders the understanding of its threats.

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Conservation Actions

It is impossible to recommend conservation actions for Cantharellus helvelloideus based on current data. As C. helvelloideus was described 120 years ago with no further collections, further research and sampling efforts are needed to understand the species' distribution, potential niche and biology. This is especially true as its type locality is in a region which is not well-sampled. Due to its apparent rarity and lack of recent data, it is crucial to better understand its taxonomy and relation with other Amazonian Cantharellus species.

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Use and Trade

No use/trade is known.

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Source and Citation

Liddle, T.A. & Wartchow, F. 2025. Cantharellus helvelloideus. The IUCN Red List of Threatened Species 2025: e.T265907687A265963137. Accessed on 27 November 2025.

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• Country occurrence