Cortinarius quadrisporus is an ectomycorrhizal species found in association with Nothofagus dombeyi and Lophozonia obliqua (Nahuelbuta National Park and San Pablo de Tregua Reserve in Chile), N. dombeyi and N. pumilio (Nahuel Huapi National Park in Argentina), and N. dombeyi, L. alpina, and L. obliqua (Villarrica National Park in Chile). This species is associated with an increasingly threatened Nothofagus forest. Deforestation, forest fires (intentional and accidental due to drought and climate change), invasive species like Pseudotsuga menziesii (Oregon pine) and cattle farming are a growing threat. Cortinarius quadrisporus is considered a rare species. No records have been made since the species publication (Nouhra et al. 2021). It is expected conservatively that there are no more than 15-30 mature individuals per site, that would be found with a greater sampling effort. Then, considering that the species is associated with an increasingly threatened Nothofagus forests (Miranda et al., 2017; CONAF 1999 and 2020), it is approximated that the current population size is no bigger than 10,000 mature individuals. The generation time of this species is 50 years, and it is inferred that due to climate change and other threats, such as deforestation, fires increase, alien species and cattle, the area suitable for the specific forest which harbors this species will decrease conservatively 15% in the next 30 years (year 2050) and, as a consequence, the population size of fungal species is in continuing decline. This species is assessed as Vulnerable - VU C2a(ii).

Cortinarius quadrisporus Nouhra & Kuhar, sp. nov. 2021, in Nouhra, Kuhar, Truong, Pastor, Crespo, Mujic, Caiafa & Smith, Mycologia. 2021 Sep-Oct;113(5):1022-1055.
Typification Details: Holotype FLAS-F-64273

This species is currently known from seven specific sites, but the area of suitable habitat where it may occur is very large. However, the population size of the species is likely to be very small, as it is reported to be very rare and in decline. Also, it is suspected that the area suitable for the specific forest which harbors this species will decrease conservatively 15% in the next 30 years (year 2050) by the climate change and other threats, such as deforestation, fires increase, alien species and cattle.

So far this species is only known from three sites in Argentina (Nahuel Huapi National Park) and in three sites in Chile (Nahuelbuta and Villarrica National Park, and San Pablo de Tregua Reserve) (2016 to 2019). The potential area that this species occupies is the Nothophagaceae forests and could also occur in central Patagonia too.

Cortinarius quadrisporus is considered a rare species. It has small-sized globose secotioid pileus, white to slightly olivaceous or yellowish brown basidiomes; occurring under Nothofagus dombeyi and N. pumilio in northern Patagonia. No records have been made since the species publication (Nouhra et al. 2021). It is expected that there are no more than 15-30 mature individuals per site, that would be found with a greater sampling effort. Then, considering that the species is associated with an increasingly threatened Nothofagus forests (Miranda et al., 2017; CONAF 1999 and 2020), it is approximated that the current population size is no bigger than 10,000 mature individuals. The generation time of this species is 50 years, and it is inferred that due to climate change and other threats, such as deforestation, fires increase, alien species and cattle, the area suitable for the specific forest which harbors this species will decrease conservatively 15% in the next 30 years (year 2050), and, as a consequence, the fungal population size is in continuing decline.

This ectomycorrhizal species so far it has been found in association with Nothofagus dombeyi and Lophozonia obliqua (Nahuelbuta National Park and San Pablo de Tregua Reserve in Chile), N. dombeyi and N. pumilio (Nahuel Huapi National Park in Argentina), and N. dombeyi, L. alpina, and L. obliqua (Villarrica National Park in Chile).

This species is associated with an increasingly threatened Nothofagus forest. Deforestation, forest fires (intentional and accidental due to drought and climate change), invasive species like Pseudotsuga menziesii (Oregon pine) and cattle farming are a growing threat.

As three of the known localities of Cortinarius galbus are within protected areas (national parks), one in both Chile and Argentina, law reinforcement is important as well as education and awareness about the species.

The biology of the species (dispersal vector, sporome-forming patterns), its ecology (habitat requirement, host specificity) and how it interacts with its Nothofagus hosts should be better understood. Further research is needed to find out whether the species is under-looked or truly rare.

No uses or trade are known so far.

Nouhra E, Kuhar F, Truong C, Pastor N, Crespo E, Mujic A, Caiafa MV, Smith ME. Thaxterogaster revisited: A phylogenetic and taxonomic overview of sequestrate Cortinarius from Patagonia. Mycologia. 2021 Sep-Oct;113(5):1022-1055. Doi: 10.1080/00275514.2021.1894535. Epub 2021 Jul 8. PMID: 34236939.

CONAF. 2020. Catastro de los Recursos vegetacionales y Uso de la Tierra.
Miranda, A.; Altamirano, A.; Cayuela, L.; Lara, A.; González, M. 2017. Native forest loss in the Chilean biodiversity hotspot: revealing the evidence. Reg Environ Change 17:285–297
DOI 10.1007/s10113-016-1010-7

CONAF. 1999. CATASTRO Y EVALUACIÓN DE RECURSOS VEGETACIONALES NATIVOS DE CHILE. Informe Nacional con Variables Ambientales. PROYECTO CONAF - CONAMA – BIRF.

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