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Presented at the Mycological Society of America's "MSA 2020: Mycology from the Cloud" virtual conference.

Full citation: Beimforde, C., Schmidt, A.R., Rikkinen, J. and J.K. Mitchell. 2020. Sareomycetes cl. nov.: A new proposal for placement of the resinicolous genus Sarea (Ascomycota, Pezizomycotina). Fungal Systematics and Evolution.

Resinicolous fungi constitute a heterogeneous assemblage of fungi that live on fresh and solidified plant resins. The genus Sarea includes, according to current knowledge, two species, S. resinae and S. difformis. In contrast to other resinicolous discomycetes, which are placed in genera also including non-resinicolous species, Sarea species only ever fruit on resin. The taxonomic classification of Sarea has proven to be difficult and currently the genus, provisionally and based only on morphological features, has been assigned to the Trapeliales (Lecanoromycetes). In contrast, molecular studies have noted a possible affinity to the Leotiomycetes. Here we review the taxonomic placement of Sarea using sequence data from seven phylogenetically informative DNA regions including ribosomal (ITS, nucSSU, mtSSU, nucLSU) and protein-coding (rpb1, rpb2, mcm7) regions.

We combined available and new sequence data with sequences from major Pezizomycotina classes, especially Lecanoromycetes and Leotiomycetes, and assembled three different taxon samplings in order to place the genus Sarea within the Pezizomycotina. Based on our data, none of the applied phylogenetic approaches (Bayesian Inference, Maximum Likelihood and Maximum Parsimony) supported the placement of Sarea in the Trapeliales or any other order in the Lecanoromycetes. A placement of Sarea within the Leotiomycetes is similarly unsupported. Based on our data, Sarea forms an isolated and highly supported phylogenetic lineage within the "Leotiomyceta". From the results of our multilocus phylogenetic analyses we propose here a new class, order, and family, Sareomycetes, Sareales and Sareaceae in the Ascomycota to accommodate the genus Sarea. The genetic variability within the newly proposed class suggests that it is a larger group that requires further infrageneric classification.

Geodina salmonicolor is shown to be a synonym of G. guanacastensis, the type and only species of the genus. Comparisons of ITS rDNA sequences of a paratype and two recent collections of G. guanacastensis with published ITS sequences of G. salmonicolor, from the Dominican Republic, show that these are nearly identical. When G. salmonicolor was erected no sequences of the type species were available. Morphological comparisons supports the conspecificity. Details regarding the description of G. salmonicolor are pointed out. A four-gene phylogeny places Geodina and Wynnea as a supported sister group to the rest of the Sarcoscyphaceae. Species in these genera share morphological traits of cyanophobic spore markings, dark angular outer excipular cells that give rise to hairs and the origin of several apothecia from a common basal stalk. Their occurrence on soil rather than on wood or plant material distinguish them from other Sarcoscyphaceae. Based on morphology, phylogenic relationships and trophic interactions we erect a new family, Wynneaceae, for Geodina and Wynnea.

Little is known about the diversity of Orbiliomycetes from Puerto Rico. Cantrell & Lodge (2008) compiled a list of the fungi from Puerto Rico, and only mentioned four species of Orbilia: O. andina, O. chysocoma, O. delicata and O. cf. gaillardii. During IMC11 in Puerto Rico, 2018, several collections of Orbiliomycetes were found in Juan Enrique Monagas Park during the Ascomycete workshop field trip. Some of these were sent to the Cornell and Farlow Herbaria. One collection caught the attention of Luis Quijada due to its interesting morphological features. This species is not related to any of the species reported by Cantrell & Lodge (2008). The morphology of the asci and ascospores of the sexual morph clearly indicates a relationship with Orbilia auricolor and related species (section Arthrobotrys). The morphology of the strongly mammiform paraphyses and the excipulum with large cortical cells with knob-like glassy caps had never before seen in this section. Our cultures produced an Arthrobotrys-like anamorph most similar to the anamorph of O. blumenaviensis (= A. vermicola), but the conidia are distinctly smaller and never more than 1-septate. Molecular data supports the placement of this Orbilia in series Arthrobotrys. Species in this series produce adhesive networks as trapping organs in the presence of nematodes, and this behavior was confirmed in cultures of this Orbilia. Our phylogenetic analysis shows this species as very distinct from O. blumenaviensis and supports it being new to science.

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The harvesting of morels is a vital economic activity for local communities in Chile because they are a significant commercial export for the country. Although many species of morels produce ascomata in the absence of fire, abundant ascomata production occurs among some Morchella species when triggered by fire. The intentional burning of Nothofagus forests in Southern Chile, as a means to increase morel production, has become a problem and has negatively impacted ecosystems. Information on the distribution of morels in South America is limited. Spegazzini (1909) described M. patagonica from Argentina and Gamundi et al. (2004) listed five Morchella species from Patagonia and surrounding areas including Spegazzini’s species. Recently Pildain et al. (2014) and Baroni et al. (2018) have examined diversity of Morchella species in South America and the Caribbean using molecular methods. To better understand which Morchella species are being commercially harvested in Southern Chile, molecular markers were used to identify collections of morels being harvested and/or sold commercially and determine their phylogenetic relationships. Morels were sampled from collections in the Fungarium of the Fundación Fungi, Chile (FFCL) and batches purchased from commercial harvesters and bulk gatherers in 2015 and 2016. DNA sequence from the EF1a, RPB1, ITS and RPB2 were obtained and used for phylogenetic analyses. This study will contribute to the knowledge of morels in South America and help to understand their phylogenetic relationships with other Morchella species found worldwide.

Fungi in the class Leotiomycetes are ecologically diverse, including mycorrhizas, endophytes of roots and leaves, plant pathogens, aquatic and aero-aquatic hyphomycetes, mammalian pathogens, and saprobes. These fungi are commonly detected in cultures from diseased tissue and from environmental DNA extracts. The identification of specimens from such character-poor samples increasingly relies on DNA sequencing. However, the current classification of Leotiomycetes is still largely based on morphologically defined taxa, especially at higher taxonomic levels. Consequently, the formal Leotiomycetes classification is frequently poorly congruent with the relationships suggested by DNA sequencing studies. Previous class-wide phylogenies of Leotiomycetes have been based on ribosomal DNA markers, with most of the published multi-gene studies being focussed on particular genera or families. In this paper we collate data available from specimens representing both sexual and asexual morphs from across the genetic breadth of the class, with a focus on generic type species, to present a phylogeny based on up to 15 concatenated genes across 279 specimens. Included in the dataset are genes that were extracted from 72 of the genomes available for the class, including 10 new genomes released with this study. To test the statistical support for the deepest branches in the phylogeny, an additional phylogeny based on 3156 genes from 51 selected genomes is also presented. To fill some of the taxonomic gaps in the 15-gene phylogeny, we further present an ITS gene tree, particularly targeting ex-type specimens of generic type species.
A small number of novel taxa are proposed: Marthamycetales ord. nov., and Drepanopezizaceae and Mniaeciaceae fams. nov. The formal taxonomic changes are limited in part because of the ad hoc nature of taxon and specimen selection, based purely on the availability of data. The phylogeny constitutes a framework for enabling future taxonomically targeted studies using deliberate specimen selection. Such studies will ideally include designation of epitypes for the type species of those genera for which DNA is not able to be extracted from the original type specimen, and consideration of morphological characters whenever genetically defined clades are recognized as formal taxa within a classification.

Triblidiaceae is a family of uncommonly encountered, non-lichenized discomycetes. A recent classification circumscribed the family to include Triblidium (4 spp. and 1 subsp.), Huangshania (2 spp.) and Pseudographis (2 spp. and 1 var.). The apothecia of these fungi are persistent and drought-tolerant; they possess stromatic, highly melanized covering layers that open and close with fluctuations of humidity. Triblidialean fungi occur primarily on the bark of Quercus, Pinaceae and Ericaceae, presumably as saprobes. Though the type species of Huangshania is from China, these fungi are mostly known from collections originating from Western Hemisphere temperate and boreal forests. The higher-rank classification of triblidialean fungi has been in flux due in part to an overemphasis on ascospore morphology. Muriform ascospores are observed in species of Triblidium and in Pseudographis elatina. An intense, dark blue/purple ascospore wall reaction in iodine-based reagents is observed in species of Pseudographis. These morphologies have led, in part, to these genera being shuffled among unrelated taxa in Hysteriaceae (Dothideomycetes, Hysteriales) and Graphidaceae (Lecanoromycetes, Ostropales). Triblidiaceae has been placed within the monofamilial order Triblidiales (affinity Lecanoromycetes). Here, we demonstrate with a three-gene phylogenetic approach that triblidialean fungi are related to taxa in Rhytismatales (Leotiomycetes). We synonymize Triblidiales under Rhytismatales and emend Triblidiaceae to include Triblidium and Huangshania, with Pseudographis placed within Rhytismataceae. A history of Triblidiaceae is provided along with a description of the emended family. We discuss how the inclusion of triblidialean fungi in Rhytismatales brings some rarely observed or even unique ascospore morphologies to the order and to Leotiomycetes.

Abstract: Species of the genus Wynnea are collected in association with a subterranean mass generally referred to as a sclerotium.

This is one of the few genera of the Sarcoscyphaceae not associated with plant material – wood or leaves. The sclerotium is

composed of hyphae of both Armillaria species and Wynnea species. To verify the existence of Armillaria species in the sclerotia of

those Wynnea species not previously examined and to fully understand the structure and nature of the sclerotium, molecular data

and morphological characters were analyzed. Using nuclear ITS rDNA sequences the Armillaria species co-occurring with Wynnea

species were identified from all examined material. These Armillaria symbionts fall into two main Armillaria groups – the A. gallicanabsnona-

calvescens group and the A. mellea group. Divergent time estimates of the Armillaria and Wynnea lineages support a

co-evolutionary relationship between these two fungi.