Cortinarius section Thaumasti in South American Nothofagaceae forests

ABSTRACT

We studied the South American species of Cortinarius section Thaumasti based on morphological and molecular data. Members of this group can easily be identified in the field because the basidiomata are small and Phlegmacium-like with a bulbous stipe and the universal veil in most species forms a distinct volva at the base of the stipe. The phylogenetic delimitation of the clade was mostly in concordance with the earlier, morphology-based grouping of the South American taxa except that C. chrysophaeus was resolved outside of the clade. Altogether nine species were recognized in the section. Four species, C. chlorophanus, C. coleopus, C. cosmoxanthus, and C. vaginatus, were previously described by other authors, whereas three species, C. chlorosplendidus, C. olivaceovaginatus, and C. subcosmoxanthus, are described here as new. We were able to identify two remaining taxa, but we do not have sufficient morphological data to allow for a formal description. All of the species in C. section Thaumasti form ectomycorrhizal associations with Nothofagaceae. They have been documented from South America and New Zealand. The Patagonian species are considered endemic to the region. A key to the described species is provided.

KEYWORDS:

• Agaricales
• fungal diversity
• DNA barcoding
• ectomycorrhizal fungi
• southern temperate forests
• 3 new taxa

ACKNOWLEDGMENTS

We thank the Administración de Parques Nacionales of Argentina for authorizing our collecting expeditions in Parque Nacional Nahuel Huapi and Parque Nacional Lanín under project 2016/720 (to E. Nouhra). The Chilean Corporación Nacional Forestal (Gerencia de Areas Silvestres Protegidas) provided permission to collect fungi in Puyehue National Park under permit no. 014/2014 (to M.E.S.). We thank R. Healy, F. Kuhar, and N. Fernandez for critical logistical support and photography help during field collecting and The Fungi Foundation for collecting and sending the specimens. Pablo Sandoval-Leiva is thanked for providing material.

Additional information

Funding

This work was supported by the US National Science Foundation grant DEB 1354802 (to M.E.S. and P.B.M.), two Bentham-Moxon Trust grants in 2016 and 2017 for field work (to T.N.), and the University of Florida Institute for Food and Agricultural Sciences IFAS via NIFA-USDA award FLA-PLP-005289 (to M.E.S.).