After a discussion of changing generic concepts in the parmelioid lichens, a checklist with the current species placements is presented. Twenty-five genera and 143 species are accepted for Europe, of which 17 genera and 112 species belong to the monophyletic parmelioid clade. The individual countries from which species are reported are provided, along with references to key publications. Synonyms used at species rank in Europe are cross-referenced, and the dates of publication of all names are provided. One new combination is made: Xanthoparmelia pulvinaris (syn. Parmelia pulvinaris, X. pseudohungarica).
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.
Bryoria fremontiiandB. tortuosaare the only species in the lichenized ascomycete genusBryoriaknown to contain the pulvinic acid derivative vulpinic acid. InB. fremontiithis yellow pigment is restricted to the soralia and apothecia, while inB. tortuosait can occur throughout the thallus. The actual amount of vulpinic acid produced byB. tortuosais rather variable, however, with intermediate specimens bearing both white and yellow pseudocyphellae. We studied the relationship between the two species with parsimony analysis using four DNA regions: 1) the internal transcribed spacers of the nuclear rDNA including the 5.8S region (ITS), 2) partial sequences from the intergenic spacer of the nuclear rDNA (IGS), 3) partial sequences from the small subunit of the mitochondrial rDNA (mtSSU), and 4) partial sequences from the protein-coding glyceraldehyde-3-phosphate dehydrogenase gene (GAPDH). Our phylogenetic analysis revealed thatB. fremontiiandB. tortuosamust be regarded as conspecific, but allowing for some genetic differentiation between European and North American populations.Bryoria tortuosais therefore synonymized withB. fremontii.