Identifying and naming the currently known diversity of the genus Hydnum, with an emphasis on European and North American taxa.

In this study, 49 species of Hydnum are recognized worldwide. Twenty-two of them are described here as new species. Epitypes are proposed for H. repandum and H. rufescens. The majority of the species are currently known only from a single continent. The barcodes produced in this study are deposited in the RefSeq database and used as a basis to name species hypotheses in UNITE. Eleven infrageneric clades recovered in a phylogenetic analysis are supported by morphological characteristics and formally recognized: subgenera Alba, Hydnum, Pallida, and Rufescentia; sections Hydnum, Olympica, Magnorufescentia, and Rufescentia; and subsections Mulsicoloria, Rufescentia, and Tenuiformia.

Multilocus phylogenetic and coalescent-based methods reveal dilemma in generic limits, cryptic species, and a prevalent intercontinental disjunct distribution in Geopyxis (Pyronemataceae s. l., Pezizomycetes).

Species limits in the small genus Geopyxis are debatable because of problems with interpreting the few phenotypic features and poor documentation of types. To clarify species boundaries and diversity, we studied the morphology of 74 specimens of Geopyxis from the Northern Hemisphere, including five types, and sequenced four loci for 57 representatives: the nuc rDNA ITS1-5.8S-ITS2 (ITS), D1-D2 domains of nuc 28S rDNA (28S), translation elongation factor (tef1), and (or) part of the second largest subunit of the RNA polymerase II (rpb2) (5-7 region). Eight species are delimited. Six species are shown to be highly supported as reciprocally monophyletic: G. aleurioides sp. nov., G. alpina s. l., G. carbonaria, G. delectans, G. korfii, and G. majalis. In addition, coalescent-based Bayesian species delimitation shows G. alpina s. l. constitutes three cryptic species: G. alpina s. str., G. deceptiva sp. nov., and G. rehmii. ITS-28S sequences of type material show that G. vulcanalis and G. foetida are synonyms of G. carbonaria. A lectotype is designated for Humaria delectans and the name is combined in Geopyxis. Morphological characters that can be used to distinguish Geopyxis species are presence/absence of a long stipe, spore size and shape, and pigmented resinous exudates in medullary and ectal excipulum. Geopyxis carbonaria and G. delectans produce apothecia almost exclusively on burned ground. Bayesian analyses detected highly supported conflicts among different loci regarding generic delimitation and species relationships. Two hypogeous genera, Stephensia and Hydnocystis, are confirmed to nest within Geopyxis. The relationships between species of Geopyxis and Tarzetta, Stephensia shanorii and Paurocotylis pila, are unresolved. Six out of eight species of Geopyxis recognized in this study have intercontinental disjunct distributions.

Three common bryophilous fungi with meristematic anamorphs and phylogenetic alliance to Teratosphaeriaceae, Capnodiales.

Bryophilous ascomycetes are an overlooked and poorly known fungal group. In this study, the extreme and small-sized niche of Polytrichum piliferum hyaline leaf tips was screened for the presence of these fungi in Finland. Three closely related species were found. Bryochiton perpusillus and Bryochiton monascus were identified from several samples, and DNA isolations revealed a third closely related species, Bryochiton sp. In addition, melanised hyphae, typical to the Bryochiton species, were present in all the samples. According to phylogenetic analyses consisting of combined small subunit (SSU), large subunit (LSU), and 5.8S rDNA sequences, and internal transcribed spacer (ITS) rDNA sequences, the species showed affinity with Teratosphaeriaceae within Capnodiales, and especially with black, meristematic species often inhabiting rock substrate in extreme environments. The connection was supported by meristematic growth of the Bryochiton species in culture. Bryochiton is the second sexual genus associated within the family Teratosphaeriaceae, and B. perpusillus, and B. monascus constitute examples of teleomorphs within a group of meristematic anamorphs. These findings emphasize the multiform diversity underlying poorly researched fungal groups, such as the bryophilous fungi.

New resinicolous Chaenothecopsis species from China.

Four new resinicolous species of Chaenothecopsis are described from China: Chaenothecopsis perforata from exudate of Rhus chinensis (Anacardiaceae), C. pallida from exudate of Ailanthus altissima (Simaroubaceae), C. resinophila from exudate of Kalopanax septemlobus (Araliaceae) and C. hunanensis from resin of Pinus massoniana (Pinaceae). All the new species are compared with previously described resinicolous mycocalicioid taxa, and several new features in these species are presented. The newly described species cannot always be distinguished by any single character, but they all possess unique combinations of morphological, chemical and ecological features. Several aspects in the ecology and evolution of boreal and tropical resinicolous species are briefly discussed.

Multiple origins of symbioses between ascomycetes and bryophytes suggested by a five-gene phylogeny.

Numerous species of microscopic fungi inhabit mosses and hepatics. They are severely overlooked and their identity and nutritional strategies are mostly unknown. Most of these bryosymbiotic fungi belong to the Ascomycota. Their fruit-bodies are extremely small, often reduced and simply structured, which is why they cannot be reliably identified and classified by their morphological and anatomical characters. A phylogenetic hypothesis of bryosymbiotic ascomycetes is presented. New sequences of 78 samples, including 61 bryosymbionts, were produced, the total amount of terminals being 206. Of these, 202 are Ascomycetes. Sequences from the following five gene loci were used: rDNA SSU, rDNA LSU, RPB2, mitochondrial rDNA SSU, and rDNA 5.8S. The program TNT was used for tree search and support value estimation. We show that bryosymbiotic fungi occur in numerous lineages, one of which represents a newly discovered lineage among the Ascomycota and exhibits a tripartite association with cyanobacteria and sphagna. A new genus Trizodia is proposed for this basal clade. Our results demonstrate that even highly specialized life strategies can be adopted multiple times during evolution, and that in many cases bryosymbionts appear to have evolved from saprobic ancestors. © The Willi Hennig Society 2009.