Friday, April 24, 2020

[Fungi • 2020] Purple Haze: Cryptic Purple sequestrate Cortinarius (Basidiomycota: Agaricomycetes) in New Zealand

Cortinarius violaceovolvatus var. viola (Soop) A.R. Nilsen & Orlovich

in Nilsen, Wang, Soop, ... et Orlovich, 2020. 

Cortinarius is a species-rich ectomycorrhizal genus containing taxa that exhibit agaricoid or sequestrate basidiome morphologies. In New Zealand, one of the most recognizable and common Cortinarius species is the purple sequestrate fungus, C. porphyroideus. We used genome skimming of the almost 100-y-old type specimen from C. porphyroideus to obtain the nuc rDNA internal transcribed spacer region ITS1-5.8S-ITS2 (ITS barcode) and partial nuc rDNA 28S (28S) sequences. The phylogenetic position of C. porphyroideus was established, and we found that it represents a rarely collected species. Purple sequestrate Cortinarius comprise multiple cryptic species in several lineages. We describe four new species of Cortinarius with strong morphological similarity to C. porphyroideus: Cortinarius diaphorus, C. minorisporus, C. purpureocapitatus, and C. violaceocystidiatus. Based on molecular evidence, Thaxterogaster viola is recognized as Cortinarius violaceovolvatus var. viola. These species are associated with Nothofagus (southern beech) and have very similar morphology to C. porphyroideus but are all phylogenetically distinct based on molecular data.

KEYWORDS: Genome skimming, Nothofagus, secotioid, Thaxterogaster, truffle-like, 5 new taxa

Cortinarius diaphorus Soop, A.R. Nilsen & Orlovich, sp. nov.

Etymology: diaphorus (Greek), διαφορος different,” as being similar, yet different from Cortinarius porphyroideus.

Cortinarius minorisporus X. Yue Wang, J.A. Cooper, A.R. Nilsen & Orlovich, sp. nov.

Etymology: minorisporus (Latin), pertains to the smaller spore size compared with other purple sequestrate species.

Cortinarius purpureocapitatus X. Yue Wang, J.A. Cooper, A.R. Nilsen & Orlovich, sp. nov.

Etymology: purpureocapitatus (Latin), pertaining to the purple color of the pileus.

Cortinarius violaceocystidiatus A.R. Nilsen & Orlovich, sp. nov.

Etymology: violaceocystidiatus (Latin), referring to the infrequent purple cystidia.

Cortinarius violaceovolvatus var. viola (Soop) A.R. Nilsen & Orlovich, comb. nov. et stat. nov.

Basidiomes of Cortinarius violaceocystidiatus var. viola (OTA64113).

Andy R. Nilsen,Xin Yue Wang, Karl Soop, Jerry A. Cooper, Geoff S. Ridley, Michael Wallace, Tina C. Summerfield, Chris M. Brown and David A. Orlovich. 2020. Purple Haze: Cryptic Purple sequestrate Cortinarius in New Zealand. Mycologia. DOI: 10.1080/00275514.2020.1730120