Hydnum pallidum Raddi, the Correct Name for H. albidum Peck in the Sense of European Authors and the Recently Described H. reginae Kibby, Liimat. & Niskanen.

The systematics of the genus Hydnum have undergone important advances, and many new species have been described with the aid of molecular data. A revision of old names that refer to Hydnum s. str., considering the knowledge now available, might reveal prioritary names of recently described species. This study focuses on the study of names that refer to white Hydnum in Europe, among which earlier synonyms of Hydnum reginae (=Hydnum albidum s. auct. pl. eur.) are potentially found, a species characterized by producing white basidiomata and smaller spores than any other European species. Our revision revealed the existence of three earlier names based on European material, namely H. pallidum Raddi, H. album Fr. and H. heimii Maas Geest. The earliest of those, Hydnum pallidum, is epitypified using material from Tuscany (Italy), from where it was originally described, and hence, it becomes the correct name for H. albidum s. auct. pl. eur. A full description and photographs of H. pallidum are provided, and further comments on other names that refer to white Hydnum based on European material are made.

Re-Valuation of the Taxonomic Status of Species within the Inocybe similis Complex.

The taxonomy of Inocybe similis and closely allied species is addressed using morphological and molecular data (nrITS and nrLSU DNA). The holotypes of I. chondrospora and I. vulpinella and the isotype of I. immigrans were studied and sequenced. Our results suggest the synonymy between I. similis and I. vulpinella as well as that between I. chondrospora and I. immigrans.

Considerations and consequences of allowing DNA sequence data as types of fungal taxa.

Nomenclatural type definitions are one of the most important concepts in biological nomenclature. Being physical objects that can be re-studied by other researchers, types permanently link taxonomy (an artificial agreement to classify biological diversity) with nomenclature (an artificial agreement to name biological diversity). Two proposals to amend the International Code of Nomenclature for algae, fungi, and plants (ICN), allowing DNA sequences alone (of any region and extent) to serve as types of taxon names for voucherless fungi (mainly putative taxa from environmental DNA sequences), have been submitted to be voted on at the 11th International Mycological Congress (Puerto Rico, July 2018). We consider various genetic processes affecting the distribution of alleles among taxa and find that alleles may not consistently and uniquely represent the species within which they are contained. Should the proposals be accepted, the meaning of nomenclatural types would change in a fundamental way from physical objects as sources of data to the data themselves. Such changes are conducive to irreproducible science, the potential typification on artefactual data, and massive creation of names with low information content, ultimately causing nomenclatural instability and unnecessary work for future researchers that would stall future explorations of fungal diversity. We conclude that the acceptance of DNA sequences alone as types of names of taxa, under the terms used in the current proposals, is unnecessary and would not solve the problem of naming putative taxa known only from DNA sequences in a scientifically defensible way. As an alternative, we highlight the use of formulas for naming putative taxa (candidate taxa) that do not require any modification of the ICN.

Phylogenetic assessment of Chromocyphellaceae (Agaricineae, Basidiomycota) and a new lamellate species of Chromocyphella.

Cyphelloid fungi represent a polyphyletic assemblage of reduced agarics, including the brown-spored family Chromocyphellaceae. In order to elucidate the phylogenetic position of Chromocyphellaceae, newly generated sequences of Chromocyphella were included in a multigene alignment of the Agaricineae and phylogenetically analyzed. The current analyses show that the Chromocyphella muscicola specimen used to phylogenetically place Chromocyphellaceae in its original description was misidentified and that the Chromocyphellaceae nests in the Hymenogastraceae, Chromocyphella being sister to Flammula. Chromocyphella is emended, including now a new species with lamellate and stipitate basidiomata, C. lamellata. The name Cymbella crouanii, type species of Chromocyphella, is lecto- and epitypified. Our analyses support a new origin of cyphelloid fungi. The shift to a cyphelloid basidioma from an agaric ancestor is suggested to have occurred in two evolutionary steps in Chromocyphella, an initial reduction in basidioma size and a subsequent loss of lamellae and stipe.

Teichospora and the Teichosporaceae.

A multigene analysis of a combined ITS, LSU, SSU, rpb2 and tef1 sequence data matrix was applied to infer the phylogenetic position of the genus Teichospora in the Pleosporales, based on isolates from freshly collected material of the generic type T. trabicola and several additional species. Phylogenetic analyses revealed that Misturatosphaeria and Floricola are synonyms of Teichospora. All species of these genera and several species recently described in the genus Curreya belong to Teichospora and are thus combined in this genus. Also, Melanomma radicans and Ramusculicola thailandica are combined in Teichospora. The new name Teichospora parva is established for Misturatosphaeria minima. Three new species, T. melanommoides, T. pusilla and T. rubriostiolata, are described, and an expanded description of T. mariae is given. The family Teichosporaceae is currently confined to Teichospora, which can be phylogenetically clearly separated from Lophiostoma, the type genus of the Lophiostomataceae. The family name Floricolaceae is a synonym of Teichosporaceae. All species described here form apically free paraphyses among immature asci. This finding contradicts the current general dogma that apically free paraphyses are absent in the Pleosporales and questions the wide use of the term pseudoparaphysis.

Unraveling the Inocybe praetervisa group through type studies and ITS data: Inocybe praetervisoides sp. nov. from the Mediterranean region.

Species in the Inocybe praetervisa group are characterized by producing nodulose to angular basidiospores and a bulbous, marginate, white stipe devoid of any pinkish to reddish tinge. Species delimitation problems and common misinterpretations in the I. praetervisa group have not yet been resolved through type studies and analysis of molecular data. This study seeks to clarify the taxonomy and nomenclature of species around I. praetervisa. Analyses of the nuc rDNA internal transcribed regions (ITS) recovered two major groups within the I. praetervisa group that can be separated on the basis of cystidial morphology. The study of three authentic and topotypic specimens in the Bresadola herbarium revealed that the name I. praetervisa has been misapplied often. The ITS region of one of the specimens was obtained, and this specimen is designated as epitype in support of a lectotype. Inocybe rivularis is demonstrated to be a later synonym of I. praetervisa, while Inocybe phaeocystidiosa is the correct name for the species most often misdetermined as I. praetervisa. Inocybe salicis-herbaceae and I. praetervisa var. flavofulvida are shown to be synonyms of I. phaeocystidiosa based on ITS sequence data from type collections. A new species sister to I. phaeocystidiosa with a Mediterranean distribution is described as I. praetervisoides. Cystidial morphology, distribution of caulocystidia, basidiospore morphology and ecology are shown to be the main diagnostic characters for separating the species. Inocybe praetervisa and I. phaeocystidiosa have a transoceanic distribution in Europe and North America, whereas I. praetervisoides so far is known only from the Mediterranean region.

Two new species of Thyronectria from Mediterranean Europe.

Two new species of Thyronectria growing in Mediterranean vegetation are described from southern Spain; they are T. giennensis from Quercus ilex ssp. rotundifolia and T. pistaciae from Pistacia lentiscus. Both species are characterized by morphology of sexual and asexual morphs and by DNA data. They have olivaceous to green-brown muriform ascospores and are closely related to T. asturiensis and T. roseovirens, as determined by multigene phylogenetic analyses of a matrix containing six loci (ITS and 28S regions of nuc rDNA, ACT1, RPB1, RPB2, TEF1 and TUB2 genes). We also report that Cucurbitaria bicolor is a synonym of Thyronectria rhodochlora, the type species of Thyronectria.

Taxonomy and phylogeny of yellow Clavaria species with clamped basidia-Clavaria flavostellifera sp. nov. and the typification of C. argillacea, C. flavipes and C. sphagnicola.

This study explores species limits of a group of Clavaria species with taxonomic and nomenclatural problems and discusses the phylogeny and circumscription of the genus. The nuc 28S rDNA (28S) and internal transcribed spacer region phylogenies resolve species relationships, and the ITS is shown to be an adequate barcode marker for Clavaria. Yellow, clamped species of Clavaria are distributed in two clades, (i) C. flavostellifera, sister to C. incarnata and C. asterospora in ITS analyses, characterized by producing ornamented spores, and (ii) C. argillacea-C. citrinorubra-C. flavipes-C. sphagnicola, with smooth spores. Clavaria flavostellifera is described as new species based on morphological and molecular characters. Molecular evidence that supports C. sphagnicola as distinct from C. argillacea is provided. The usefulness of spore ornamentation as a taxonomic character is discussed; it is present only in some taxa and then only on spores trapped in the hymenium. Descriptions of C. argillacea, C. flavipes and C. sphagnicola are provided, along with color photographs and a key to yellow species of Clavaria with clamped basidia. Camarophyllopsis and Clavicorona are recovered within a paraphyletic Clavaria in our 28S phylogeny. Clampless contextual hyphae and narrow, slightly thick-walled mycelial hyphae are proposed as synapomorphies of Camarophyllopsis and Clavaria.

Two new species of Hydnum with ovoid basidiospores: H. ovoideisporum and H. vesterholtii.

Two new species of Hydnum, characterized by slender Hydnum rufescens-like basidiomes and ovoid to broadly ellipsoid basidiospores, are described from the Iberian Peninsula based on morphological and ITS molecular data. Hydnum ovoideisporum is distinguished by pilei with deep orange tones and strong preference for calcareous soil. It is widespread in the Iberian-Mediterranean area. Hydnum vesterholtii is characterized by its ocher to light ocher pileus, and nearly all the collections were made in the Pyrenees. Both ovoid-spored species are monophyletic well supported groups in the maximum parsimony and Bayesian ITS phylogenies, while the remainder of the samples assigned to H. rufescens s.l. and having globose basidiospores split into six well supported clades. The need to typify the name Hydnum rufescens is discussed, and a provisional key is given for the European taxa of Hydnum.

Species delimitation in the European species of Clavulina (Cantharellales, Basidiomycota) inferred from phylogenetic analyses of ITS region and morphological data.

The identification of the conventionally accepted species of Clavulina (Cantharellales, Basidiomycota) in Europe (Clavulina amethystina, Clavulina cinerea, Clavulina cristata, and Clavulina rugosa) is often difficult and many specimens are not straightforwardly assignable to any of those four species, which is why some authors have questioned their identity. In order to assess the status of those species, a morphological examination was combined with the molecular analysis of the ITS region. The same six major clades were obtained in the Bayesian and parsimony phylogenetic analyses, and all six clades were well-supported at least by one of the analyses. Morphological characters, such as the overall branching pattern, the presence and intensity of grey colour, the cristation of the apices, and basidiospore size and shape were to various extents correlated with the phylogenetic signal obtained from the ITS region. The congruence between the molecular analyses and morphology, rather than geographical origin, suggests the existence of several species that can be delimited using a combined phylogenetic and morphological species recognition. The analyses revealed that C. cristata and C. rugosa are well-delimited species. In contrast, more than one taxa could be subsumed under the names C. amethystina and C. cinerea, the taxonomical complexity of which is discussed. The ITS region is proved to be adequate to separate phylogenetic species of Clavulina.