• Proposed
  • Under Assessment
  • NTPreliminary Assessed
  • 4Assessed
  • 5Published

Amanita torrendii Justo

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Scientific name
Amanita torrendii
Common names
Torrend's Dry Caesar
Torrendie délicate
Weisser scheidenstäubling
IUCN Specialist Group
Mushroom, Bracket and Puffball
Assessment status
Preliminary Assessed
Preliminary Category
NT A2+A3+A4
Proposed by
Susana C. Gonçalves
Susana C. Gonçalves
Comments etc.
Anders Dahlberg, Irmgard Krisai-Greilhuber

Assessment Notes

Check Medderrranan distribution Present i Egypt, Turkey? Verify the stronghold in Spain/Portugal
Su: Emailed Ahmed M. Abdel-Azeem (28 April 2021)

Argue for A-citeria.

Note to self (Su): Map needs to be done (GBIF points OK) and references entered. Red List justification still needs to be written.

If the number of mature individuals does not exceed 20000, then criterion C1 can be applied assuming a decline of > 10% in 3 generations >> NT
If the number of mature individuals is estimated to exceed 20000, then A criterium (A2+A3+A4) can be applied based on habitat and host decline inference > 15 % >> NT

During this evaluation, it was possible to correct one record, erroneously attributed to the USA (MICH herbarium and attributed to C.G. Lloyd). Corrected record here > http://mycoportal.org/portal/collections/individual/index.php?occid=350450 )

Taxonomic notes

Synonym: Torrendia pulchella Bres.

Amanita torrendii was originally described as Torrendia pulchella by Bresadola (1902). Justo et al. (2010) transferred it to Amanita section Caesareae based on molecular data.

Why suggested for a Global Red List Assessment?

Geographic range

Amanita torrendii has so far only been recorded in four countries in Europe (Spain, Portugal, France, and Italy), two countries in Africa (in the Atlas Mountains in Morocco and Algeria), and one in Asia (Turkey), a typical distribution around the Mediterranean Sea basin. The southern limit of distribution is unclear due to a lack of data (e.g. a single historical occurrence in Sierra Leone from 1905 by G. Malecón in GBIF).

Ask Ahmed

Population and Trends

Condese the documentation and have a reasoning abut facors causing habitat decline ending up with an estimate of around 20 %.
Suggestion to assess it as NT using the A-criteria.

In 2015, the number of known sites for Amanita torrendii was about 100, most in the Iberian Peninsula (Fraiture and Otto 2015); only 7 in France (including three in Corsica), and four in Italy (of which three in Sardinia). The occurrences currently recorded in GBIF support the view of an Iberian stronghold. Of the 197 occurrences recorded in GBIF, 152 are from Spain (but correspond to a much smaller number of localities) and 33 are from Portugal.

The total number of localities is likely significantly higher but should not exceed 2000. With an average number of 10 mature individuals at each locality (Dalhberg & Mueller 2011), the total number of mature individuals will not exceed 20000. (then C)
It is a very particular taxon and therefore sought after by mycologists.
The total number of localities is likely significantly as much as XTIMES higher. With an average number of 10 mature individuals at each locality (Dalhberg & Mueller 2011), the total number of mature individuals will exceed 20000. [(then A)
The distribution area and thus the population size is potentially larger (?) - thinking Africa and Asia.

In Europe, A. torrendii is confined to the Mediterranean region and its most common habitat is Quercus suber (cork oak) forests. The conservation status of this habitat in the region is ‘Unfavourable-Bad’ due to reports from Portugal and Spain based on poor and/or bad status in terms of area, structure and functions (habitat quality), and future prospects (European Environment Agency, 2013-2018). This lower status in comparison with the previous assessment period (2007-2012; ‘Unfavourable-Inadequate’) indicates the ongoing decline of this type of habitat in the stronghold of the species. As a whole, the Mediterranean basin is subject to many simultaneous pressures (FAO and Plan Bleu 2018). With a growing population and a climate that is expected to become drier and warmer, the pressure on Mediterranean forests is enormous. Direct causes of decline include conversion of forests to fire-prone shrub communities, outbreaks of pests and pathogens, and increased forest fires. According to the IUCN Red List, the population of Quercus suber, the species’ main host, is also decreasing (Barstow and Harvey-Brown 2017).

C1 The total number of mature individuals of A. torrendii will not exceed 20,000, and there has been a continuing decline of the species’ most important habitat and host of at least 15% due to increasing human pressure and climate change. It is anticipated that this decline will continue at the same rate over the next 50 years (three generations; Dahlberg and Mueller 2011). This species forms ectomycorrhizas, so the decline in hosts directly negatively impacts the population size of the species.
A2+A3+A4- Given the past and ongoing decline of its habitat and host tree, the population size of A. torrendii is inferred to be reduced by at least 15% over 50 years (three generations, Dahlberg and Mueller 2011).

Population Trend: Decreasing

Habitat and Ecology

Amanita torrendii is a typically Mediterranean species that occurs only in the Mediterranean and sub-mediterranean forests and shrublands in sandy soils. It is ectomycorrhizal with Quercus spp. (especially Q. suber), Pinus spp. (P. pinaster and P. pinea), Cistus spp. and, possibly, also with Castanea sativa. The species occurs in the following NATURA 2000 habitats (codes): 2180, 2270, 9230, 9260, 9330 (Quercus suber forests, the most common habitat), 9340, and 9540.

Temperate ForestMediterranean-type Shrubby Vegetation


The species is threatened by forest cutting and loss of habitat connectivity, and the modification of semi-natural woodlands management regimes, e.g. overgrazing. Climate change is a growing concern, with increased wildfires, pervasive drought stress and diseases affecting the species’ main host, Quercus suber.

Housing & urban areasTourism & recreation areasShifting agricultureAgro-industry grazing, ranching or farmingIncrease in fire frequency/intensityInvasive non-native/alien species/diseasesHabitat shifting & alterationDroughts

Conservation Actions

About half of the localities are part of the Natura 2000 network and hence thought protected, but appropriate management, e.g. preventing overgrazing might be needed.

Resource & habitat protectionSite/area managementHabitat & natural process restoration

Research needed

Distribution, population size and threats to populations in Africa should be investigated.

Whih host?

Population size, distribution & trends

Use and Trade



Alfredo Justo, Ingo Morgenstern, Heather E. Hallen-Adams & David S. Hibbett (2010). Convergent evolution of sequestrate forms in Amanita under Mediterranean climate conditions. Mycologia 102: 675-688.

Bresadola G. 1902. Mycetes Lusitanici novi. Atti Imp. Regia Accad. Rovereto, ser. 3, 8:132.

Fraiture A. & Otto P. (eds) 2015. Distribution, ecology and status of 51 macromycetes in Europe. Results of the ECCF Mapping Programme. Scripta Botanica Belgica 53, Botanic Garden Meise.

Dahlberg A. & Croneborg H. (2003). 33 threatened fungi in Europe. Complementary and revised information on candidates for listing in Appendix I of the Bern Convention. A document compiled for EU DG Environment and the Bern Convention by Anders Dahlberg
and Hjalmar Croneborg at the Swedish Species Information Centre on behalf of the Swedish Environmental Protection Agency (EPA) and the European Council for Conservation of Fungi (ECCF).

MyCoPortal http://mycoportal.org/portal/collections/individual/index.php?occid=350450

Country occurrence

Regional Population and Trends

Country Trend Redlisted