Assessment Notes

Justification

Bresadolia paradoxa is a conspicuous edible species known from 19 sites within the Amazon forest in Brazil and Colombia, and the southeastern and southern Brazilian Atlantic Forest, expanding its distribution to the Missiones region in Argentina, and Alto Paraná in Paraguay, being expected to mainly occur in these areas and conditions. Another three sites are located in gallery forests within the Cerrado in central-western Brazil, the Chaco in Argentina, and humid forests in Costa Rica. The species is consumed, harvested, and commercialized by indigenous populations, its use being considered safe. It is uncommon throughout its wide range, although it produces conspicuous basidiomata and a great sampling effort has been made in its habitat. Although there is a continuous and high sampling effort in Atlantic Forest areas within northeastern Brazil, the species was never collected in this region. A reduction of area in the Brazilian Atlantic Forest of around 13% is expected to be met in 50 years (three generations). In the Amazon, the B. paradoxa population is mainly threatened by impacts of climate change, where a habitat extent reduction of around 24% is expected to be met in the same time frame. For both biomes, considering the impacts of habitat fragmentation in small patches, there will also be reductions in habitat quality, and so there can be suspected a loss of around 30% of suitable habitat in that time frame, directly impacting at the same proportion of the population. Based on the habitat area and quality losses within the next 50 years (three generations), B. paradoxa is considered Vulnerable under A3c.

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Geographic range

Bresadolia paradoxa was described from east Paraguay (unknown locality) and there are additional records to Alto Paraná in Paraguay, to the Chaco and Misiones provinces in Argentina, in Casanare province in Colombia, Limón province in Costa Rica, and central-western, northern, southern and southeast Brazil and in the Atlantic and Amazon forests (Motato-Vásquez et al. 2018, GBIF.org 2024).

The records from Brazil include preserved fragments of Atlantic Forest in the states of Espírito Santo (Santa Teresa), Paraná (Foz do Iguaçu), São Paulo (Caraguatatuba, Eldorado, Ilhabela, Iporanga, and São Paulo), Rio de Janeiro (Paraty), and Rio Grande do Sul (Porto Alegre and São Leopoldo); in the Amazon Forest for the state of Roraima (Awaris region); and in the state of Mato Grosso, in the city of Primavera do Leste, with only on collection restricted to gallery forest regions within the Cerrado biome, where the phytophysiognomy is similar to the Atlantic Forest and Amazon biomes (Sanuna et al. 2016, Motato-Vásquez et al. 2018, GBIF.org 2024). It is expected that the species also occurs in other Central American countries and other Amazonian regions, as some occurrences were wrongly identified as Polyporus udus.

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Population and Trends

Bresadolia paradoxa is a conspicuous species that produces large basidiomata (usually 10 cm pileus in diameter), which grow solitarily or dispersed with up to 10 basidiomata on the same dead hardwood log. There are about 48 known collections from around 22 known sites in Argentina, Brazil, Colombia, Costa Rica, and Paraguay. In South America, the species is expected to be predominantly restricted to south and southeastern Atlantic Forest in Brazil, and reaching the Missiones region in Argentina and the Alto Paraná region in Paraguay, both with equivalent phytophysiognomies to the Brazilian Atlantic Forest. Although there is a continuous and high sampling effort in Atlantic Forest areas within northeastern Brazil, the species was never collected in this region, and thus it is believed that its distribution does not reach higher latitudes in this biome. Additionally, the species has an occurrence in the gallery forests within the Cerrado biome, which are formations similar to humid tropical forests. Therefore, it is expected that the species does not occur in dry areas of the Cerrado, and originally the species' population must be connected from Amazon to the Atlantic Forest by those gallery forest patches. B. paradoxa also occurs in the Amazon region within Brazil and Colombia extending its distribution to humid forests in Central America, within Costa Rica. It is expected to occur as one single subpopulation in an estimated 3,000 sites, each containing up to 33 mature individuals, giving about 100,000 mature individuals in total.

Although conspicuous and with a significant population size expected, the species is not so common considering the long term sampling in the Amazon and Atlantic Forests. The species' habitat is threatened mainly by historical and continuing urbanization in the Atlantic Forest (Tabarelli et al. 2010, Rezende et al. 2018) and climate change impacts in the Amazon. Considering the annual area loss in the Brazilian Atlantic Forest from 1985-2018 of 0.25% (da Silva et al. 2020) and a continuing decline, a habitat reduction of around 13% is expected to be met in 50 years. In the Amazon, the B. paradoxa population is mainly threatened by impacts of climate change, where a habitat reduction of around 24% is expected to be met in the same time frame (Zhang et al. 2015). For both biomes, considering the impacts of habitat fragmentation in small patches, there will be additional impacts on the species from the reduction of habitat quality (Berglund and Jonsson 2003, Haddad et al. 2015), which can then be extrapolated to loss of around 30% of suitable habitat. Considering those threats, it is suspected that the species will suffer a reduction of at least 30% in the next 50 years (three generations). A population reduction was suspected in light of the extension loss of suitable habitat (Zhang et al. 2015, da Silva et al. 2020) and the putative negative influence that habitat degradation has on species' occupation in a given environment (Berglund and Jonsson 2003, Haddad et al. 2015).

Population Trend: decreasing

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Habitat and Ecology

Bresadolia paradoxa is a conspicuous species that produces large basidiomata (10 cm pileus in diameter) which grows solitarily or dispersed with up to 10 basidiomata on the same dead hardwood log. Most records are from well-preserved forest fragments within the Atlantic Forest and the Amazon, but some of them are from fragments in or close to urban areas.

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Threats

Although the species' population spans to other biomes, such as the Chaco and specific formations in the Cerrado, most of the collections are within the Amazon and the southeastern and southern Atlantic Forest. Therefore, the main threats considered are related to these two regions. Deforestation in the Atlantic Forest has largely declined over the last two decades, but losses are due mainly to urbanization. However, it has been heavily exploited, and only 28% of its natural coverage remains, largely composed by forest fragments and secondary forests (Tabarelli et al. 2010, Rezende et al. 2018). Although Missiones is the most preserved fragment of Atlantic Forest in Argentina, only about 17% of the province is in protected areas (Izquierdo et al. 2008).

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Conservation Actions

The main conservation action to benefit the species' population is the protection of its habitat. Large fragments should be a priority to conserve the species as it guarantees habitat quality. The maintenance and enforcement of already placed conservation units it is also required. As the outcomes of climate change are among the main threats to the species' population and its habitat, ex situ conservation based on in vitro cultures are necessary to protect the species' genetic diversity without the influence of these factors.

New collections are needed to better understand the distribution of the species, in other countries with Amazon Forest where the species probably occurs, but also where it has not been or have been poorly reported, such as in the Atlantic Forest in northeastern Brazil and in central-western Brazil, in the Cerrado biome. The cultivation potential and medicinal properties of the species also need to be further studied. The large scale harvest to commercial purposes of the species needs to be better understood regarding negative impacts in its population stability.

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Use and Trade

The species is edible and has been reported to be used by the Sanoma indigenous people, part of the Yanomami people, who inhabit the Awaris region, in the mountain forests of the extreme northwest of Roraima, Brazil. The species is also traded by them in a mushroom mix that may contain more than 10 mushroom species and is a product of the Yanomami agricultural system. Basidiomata of Bresadolia paradoxa found in the state of São Paulo, southeast Brazil, have been consumed as food by experienced mycologists.

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Source and Citation

Menolli Jr, N. & Alves-Silva, G. 2024. Bresadolia paradoxa. The IUCN Red List of Threatened Species 2024: e.T265094574A265151930. .Accessed on 30 October 2024

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• Country occurrence