Infraspecific variation of some brown Parmeliae (in Poland) - a comparison of ITS rDNA and non-molecular characters Author Szczepanska, Katarzyna https://orcid.org/0000-0002-7752-3024 Department of Botany and Plant Ecology, Wroclaw University of Environmental and Life Sciences, pl. Grunwaldzki 24 a, PL- 50 - 363 Wroclaw, Poland katarzyna.szczepanska@upwr.edu.pl Author Guzow-Krzeminska, Beata https://orcid.org/0000-0003-0805-7987 Department of Plant Taxonomy and Nature Conservation, Faculty of Biology, University of Gdansk, Wita Stwosza 59, PL- 80 - 308 Gdansk, Poland Author Urbaniak, Jacek https://orcid.org/0000-0002-1300-0873 Department of Botany and Plant Ecology, Wroclaw University of Environmental and Life Sciences, pl. Grunwaldzki 24 a, PL- 50 - 363 Wroclaw, Poland text MycoKeys 2021 2021-12-22 85 127 160 http://dx.doi.org/10.3897/mycokeys.85.70552 journal article http://dx.doi.org/10.3897/mycokeys.85.70552 1314-4049-85-127 9BE6BB9F2C2850CD9A64958C2F3D777A Cetraria commixta (Nyl.) Th. Fr. Platysma commixtum Lichenographia Scandinavica 1:109 (1871) ≡ Platysma commixtum Nyl., Synopsis methodica lichenum 1:310 (1860) ≡ Melanelia commixta (Nyl.) A. Thell, Nova Hedwigia 60:417 (1995) ≡ Cetrariella commixta (Nyl.) A. Thell & Kaernefelt , Mycological Progress 3:309 (2004). Description. C. commixta is a foliose species with elongated, smooth and flat lobes, 0.25-2.5 mm broad, which are thick on the margins and rounded at the ends ( Szczepanska and Kossowska 2017 ). Its upper surface is glossy, olive-brown to dark brown or almost black. The lower surface is pale brown, but darker in the centre, with single, dark rhizines. C. commixta possess rounded or slightly elongated pseudocyphellae, which are present only on the margins and edges of lobes and cylindrical, marginal pycnidia, producing hyaline, citriform conidia (3-4 x 1-1.5 µm ). Apothecia are marginal, constricted at base, 0.2-7 mm diam., with hyaline, ellipsoid to oblong-ellipsoid ascospores (6-8 x 4-6 μm ). Chemistry. α-collatolic acid (chemotype I) or no substances (chemotype III). Distribution. C. commixta is a circumpolar and arctic-alpine species ( Otte et al. 2005 ), growing mainly in mountain sites, in open places with high precipitation, on natural acid, siliceous rocks in North America and Europe. Available molecular data concern samples collected in North America (Canada, Greenland), as well as North (Finland, Norway, Sweden) and West (Spain) Europe. Haplotypes differentiation. We identified seven different haplotypes (Fig. 2 , Table 2 ) within C. commixta (n = 17) that differ from each other in one or two positions, except for a single Canadian sample that differs in at least eight positions. The most common haplotype was found in ten specimens occurring in Greenland and North and Central Europe, amongst them being three newly-sequenced specimens (samples 37 and 97 from Poland and sample 129 from Germany). Moreover, two Polish specimens (samples 36 and 124 from the Sudety Mountains) represent a unique haplotype that differs from the most common one in a single position. Five haplotypes identified in our dataset were represented by single specimens originating from Greenland (3 haplotypes), Canada or Spain. Figure 2. Haplotype network, based on ITS rDNA sequences from specimens of Cetraria commixta . Newly-generated sequences are described with isolate numbers preceding the species names. Sequences downloaded from GenBank are described with their accession numbers. Mutational changes are presented as numbers in brackets near lines between haplotypes.