Assessment Notes

Justification

The ectomycorrhizal fungus Cantharellus albidolutescens is only known from rain forest in central-eastern Madagascar. The population size is estimated to be relatively small (1,250-5,000 mature individuals), and separated into at least two subpopulations, and based on current knowledge it has a restricted range (<10,000 km²). There has been rapid forest cover loss within its range over recent years, due to ongoing threats such as logging and agricultural spread. While it is difficult to translate forest cover loss to changes in population size of this species, it is suspected that the species has declining at a rate of >50% over three generations (50 years). Therefore, it is listed as Endangered under criterion A4c.

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Geographic range

Cantharellus albidolutescens has only been recorded from humid forest in central-eastern Madagascar, in the Special Reserve of Ambohitantely and at Andasibe (Buyck et al. 2015). Based on the mapped range, the extent of occurrence could be as small as less than 10,000 km², but without further information it is not possible to estimate the area of occupancy.

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Population and Trends

Buyck et al. (2015) state the species appears to occur singly on in small groups. Based on this information, and Dahlberg and Mueller (2011), a scaling factor of five mature individuals per functional individual is tentatively used here. At the moment the species is known from only two sites, but five separate collections have been made from Special Reserve of Ambohitantely. Taking into account additional suitable habitat in the surrounding area, there could be a further 50-100 sites. If these are treated as if they might be the same quality as Special Reserve of Ambohitantely (i.e. five functional individuals per site), then the total population size could fall in the range 1,250-2,500 mature individuals. However, this does assume that all functional individuals have been identified in Special Reserve of Ambohitantely. Thus this could be an underestimate, and there could be many more functional individuals present. The maximum value is, therefore, doubled to 5,000 mature individuals but this is a very tentative estimate. The Andasibe site is isolated from the Special Reserve of Ambohitantely site, and so we could assume that there are multiple subpopulations. It is unlikely that there will be a significant number of mature individuals in the Andasibe population, and so the largest subpopulation could be said to contain 1,000 mature individuals, but the true figure is essentially unknown.

There have been rapid declines in the amount of forest cover in eastern Madagascar (see World Resources Institute 2021). Protected areas within the range have been affected relatively less than other areas, but even so the amount of forest cover (at 30% canopy cover) declined by 27% within the mapped range from 2001 until 2019 (World Resources Institute 2021). The three generation period for this species is 50 years, though (see Dahlberg and Mueller 2011). Assuming that canopy cover loss continues at a similar rate, then the amount of reduction within the species’ range could be 56-58%. While it is difficult to accurately translate canopy cover loss to population changes (e.g. how much of the loss is of primary forest, and to what extent does the species persist in areas of secondary forest), the ongoing population reduction may be precautionarily suspected to exceed 50% over three generations (tentatively placed in the range 50-79%).

Population Trend: Decreasing

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Habitat and Ecology

This ectomycorrhizal fungal species was found on soil in dense humid forest (Buyck et al. 2015). At both known sites, the species was found in forest with Uapaca densifolia, while in Special Reserve of Ambohitantely, the forest also contained Leptolaena and Sarcolaena spp. (Buyck et al. 2015).

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Threats

There has been rapid forest cover loss in eastern Madagascar, particularly over recent years. Drivers of this include land conversion for agriculture, in addition to logging activities.

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Conservation Actions

Ensuring effective protection of remaining rain forest in eastern and central Madagascar is imperative. This will require engagement with local stakeholders. Further searches should take place to see if this species is more widespread than currently known.

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Use and Trade

There is no information available on this species’ use/trade.

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Source and Citation

Westrip, J.R.S. 2025. Cantharellus albidolutescens. The IUCN Red List of Threatened Species 2025: e.T189958596A270102938. Accessed on 22 November 2025.

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• Country occurrence