- Proposed
- Under Assessment
- Preliminary Assessed
- Assessed
- NTPublished
Rubroboletus rhodoxanthus (Krombh.) Kuan Zhao & Zhu L. Yang
- Scientific name
- Rubroboletus rhodoxanthus
- Author
- (Krombh.) Kuan Zhao & Zhu L. Yang
- Common names
Ruddy Bolete
Rosensopp
papegøyerørsopp
Blasshütiger Purpurröhrling
Roodnetboleet
hřib nachový
Боровик розовокожий- IUCN Specialist Group
Mushroom, Bracket and Puffball- Kingdom
- Fungi
- Phylum
- Basidiomycota
- Class
- Agaricomycetes
- Order
- Boletales
- Family
- Boletaceae
- Assessment status
- Published
- Assessment date
- 2019-03-26
- IUCN Red List Category
- NT
- Assessors
- Krisai-Greilhuber, I.
- Reviewers
- Mueller, G.M.
Assessment Notes
Justification
Rubroboletus rhodoxanthus is a well-known bolete with a beautiful greyish cap, red pores and a stem with a red net. It is confined to Europe with its main distribution in the Mediterranean region but sparsely following the distribution of beech and oak to northern Europe, its mycorrhizal tree-species. It occurs in broadleaf deciduous and evergreen forests in climax state. It is considered rare and threatened in most of its area and is red-listed in 13 European countries. It is mainly confined to older beech and oak stands, but also occurs with old trees in parks and along roads. The total number of localities is suspected not to exceed 1000. It is threatened by loss and decline of habitat, due to forestry and oak decline.Oak decline in Asia, Europe, and the United States is known since the early 1900s. In recent decades reports of oak decline have increased. This decline occurs wherever oaks are present over a wide range of sites of the northern hemisphere and the basic process of decline is similar in all places. Drought, pathogens and defoliation are the most common stress agents. Major climatic events also are triggering factors, e.g. in Europe (Gottschalk and Wargo 1996, Keča et al. 2016).
The population is suspected to have declined by 20-30% during the last 50 years (3 generations), the decline is ongoing and suspected to continue in the future. The number of mature individuals is conservatively estimated to be around 10 000 and each subpopulation to consist of less than <250 individuals.
The species is for the time being assessed as NT. Better documentation on the habitat decline rate is recommended as it could reveal a higher threat category.
Geographic range
It is widespread in the Mediterranean region, occurs in the temperate parts of Europe and is occasionally found as far north as the limit of the oak distribution.Population and Trends
Rubroboletus rhodoxanthus is a conspicuous, colourful and large bolete that is well-known, easily recognizable and much searched for. Hence, its distribution, occurrence and status is fairly well known. The species is rare and threatened in most countries of its occurrence. It is included on the red lists of thirteen European countries. Being confined mainly to older Fagus and Quercus stands, and to isolated old trees in parks and along roads, it is threatened by host death, clear cutting or removing old park trees, which abruptly stops the life of this mycorrhizal fungus.
Oak decline in Asia, Europe, and the United States is known since the early 1900s. In recent decades reports of oak decline have increased. This decline occurs wherever oaks are present over a wide range of sites of the northern hemisphere and the basic process of decline is similar in all places. Drought, pathogens and defoliation are the most common stress agents. Major climatic events also are triggering factors, e.g. in Europe. Oak forests are declining all over the world (Gottschalk and Wargo 1996, Keča et al. 2016). The decline of the old-growth oak forests in the evaluation period (50 years) is estimated to be about 30% (Hansen and Delatour 1999, Denman et al. 2014).
The currently known number of localities of this bolete in Europe is about 550. The total number of localities, including not yet recorded ones, is estimated to be less than 1000 and the total population size possibly to be around 10,000 mature individuals, and each subpopulation to consist of less than 250 individuals. The population of this speices is suspected to have declined by 20-30% during the last 50 years (3 generations); the decline is ongoing and suspected to continue in the future.
Population Trend: decreasing
Habitat and Ecology
Rubroboletus rhodoxanthus forms mycorrhiza with beech (Fagus) and oaks (Quercus) in broadleaf deciduous and evergreen forests in climax state on calcareous sandy or sandy-loamy soils. It may also occur in chestnut coppices, in roadside verges and in parks with isolated old trees. It grows from sea level and up into mountainous areas.Threats
It is threatened by habitat loss and reduced habitat quality due to forestry (e.g. clear cutting). In some countries it may be threatened by side effects of harvesting edible mushrooms in large quantities, e.g. of litter and soil and intensive trampling.Conservation Actions
Habitat protection of known sites, where a management system ensuring the right age profile in the stands of the tree partner should be implemented.Research on distribution, population trends and the ecological requirements of the species is needed.
