Taxonomic novelties and new records of Fennoscandian crustose lichens

We present taxonomic, distributional and ecological notes on Fennoscandian crustose lichens and lichenicolous fungi, based on new collections as well as revision of herbarium material. Two new combinations are proposed: Frutidella furfuracea comb. nov. for F. pullata and Puttea duplex comb. nov. for Fellhanera duplex. Lecidea byssoboliza, L. carneoglauca and Variolaria torta are all reduced to synonymy with Bacidia antricola, Bacidia invertens is synonymized with B. igniarii, B. atrolivida with Mycobilimbia tetramera, and Gyalidea fruticola with Thelenella pertusariella. A new description is provided for Micarea hylocomii. 25 species of lichens and lichenicolous fungi are reported as new to Finland, Norway and/or Sweden: Absconditella lignicola (Norway), Bacidia antricola (Norway), B. polychroa (Norway), B. pycnidiata (Sweden), Bacidina adastra (Sweden), Biatora veteranorum (Norway), Briancoppinsia cytospora (Finland), Catillaria scotinodes (Norway), Cliostomum subtenerum (Norway), Dirina fallax (Sweden), Fellhaneropsis almquistiorum (Norway), Gyalidea subscutellaris (Sweden), Lecania inundata (Norway), L. suavis (Norway), Micarea capitata (Norway), M. deminuta (Norway), M. hylocomii (Sweden), M. lynceola (Sweden), M. soralifera (Sweden), M. subconfusa (Sweden), Mycoblastus sanguinarioides (Finland, Sweden), Paralecia pratorum (Sweden), Puttea duplex (Sweden), Sarcogyne algoviae (Finland) and Toninia subnitida (Norway). Lectotypes are designated for Bacidia antricola, Lecidea byssoboliza, Lecidea carneoglauca, Lecidea subconfusa and Lecidea submoestula

Global assessment of genetic variation and phenotypic plasticity in the lichen-forming species Tephromela atra

Understanding how many species exist and the processes by which they form remains a central topic of ecological and evolutionary biology, but represents a special challenge within microbial groups. The lichen-forming fungi represent one of the best examples in which species evolution and diversity create patterns of high phenotypic plasticity coupled with wide geographic distributions. We sampled the lichen-forming species Tephromela atra and related species at a world-wide scale to reconstruct a phylogenetic hypothesis using three nuclear markers. Samples were also studied for morphological and chemical traits to assess how well the phenotypic relationships with species, previously segregated from T. atra, agrees with molecular data. We used a genealogical concordance approach and identified 15 monophyletic clades, which may represent independent lineages. By combining morphological and chemical characters, ecological preferences and geographic origin we distinguish six different species. Although subtle phenotypical traits are frequently used for describing previously cryptic species in fungi, the continuum of variability found in morphology and chemical patterns in T. atra prevents the description of new taxa with characteristic traits. We observed that phenotypic characters arise in parallel at local or regional scale but are not correlated with genetic isolation. Therefore, they are insufficient for characterizing species with broad geographic ranges within T. atra

Diagnostics for a troubled backbone: testing topologicalhypotheses of trapelioid lichenized fungi in a large-scalephylogeny of Ostropomycetidae (Lecanoromycetes)

Trapelioid fungi constitute a widespread groupof mostly crust-forming lichen mycobionts that are key tounderstanding the early evolutionary splits in theOstropomycetidae, the second-most species-rich subclassof lichenized Ascomycota. The uncertain phylogeneticresolution of the approximately 170 species referred tothis group contributes to a poorly resolved backbone forthe entire subclass. Based on a data set including 657newly generated sequences from four ribosomal and fourprotein-coding gene loci, we tested a series of a priori andnew evolutionary hypotheses regarding the relationshipsof trapelioid clades within Ostropomycetidae. We foundstrong support for a monophyletic group of nine coretrapelioid genera but no statistical support to reject thelong-standing hypothesis that trapelioid genera are sisterto Baeomycetaceae or Hymeneliaceae. However, we canreject a sister group relationship to Ostropales with highconfidence. Our data also shed light on several longstandingquestions, recovering Anamylopsoraceae nestedwithin Baeomycetaceae, elucidating two major monophyleticgroups within trapelioids (recognized here asTrapeliaceae and Xylographaceae), and rejecting themonophyly of the genus Rimularia. We transfer elevenspecies of the latter genus to Lambiella and describe thegenus Parainoa to accommodate a previously misunderstoodspecies of Trapeliopsis. Past phylogenetic studies inOstropomycetidae have invoked Bdivergence order^ fordrawing taxonomic conclusions on higher level taxa.Our data show that if backbone support is lacking, contrastingsolutions may be recovered with different oradded data. We accordingly urge caution in concludingevolutionary relationships from unresolved phylogenies

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.Peer reviewe