The new lignicolous species Micarea latispora is described from central Sweden based on morphological and molecular evidence. The species grows on decaying wood of deciduous trees, particularly Populus tremula, in open to semi-shaded conditions, and is characterized by Sedifolia-grey pigmentation in the epithecium and hymenium, unicellular, often ovoid ascospores, and by containing gyrophoric acid. It is similar to M. misella, from which it differs in having broader ascospores [(3–)3.5–4.5(–5) μm wide vs. 2–3(–3.5) μm in M. misella], a better developed thallus containing gyrophoric acid, and the absence of stipitate pycnidia. Micarea denigrata, which also contains gyrophoric acid and has similar apothecia, differs by having narrower ascospores [2–3.5(–4) μm] that are predominantly 1-septate rather than unicellular. Micarea latispora is currently known from three provinces in central Sweden, but is likely more widespread and may have been overlooked due to its superficial resemblance to related species.
Lichenicolous fungi represent an essential, but still insufficiently studied, component of the mycobiota of Europe. The steppe zone of Ukraine, despite its high ecological heterogeneity and conservation importance, has remained particularly underexplored. In this study, we provide a comprehensive revision of lichenicolous fungi occurring in the steppe zone of Ukraine based on extensive field collections from the last decade and a critical evaluation of published data. A total of 168 species are confirmed for the region, including ten species reported here for the first time from Ukraine: Arthonia urceolata, Endococcus verrucosus, Gonatophragmium lichenicola, Lichenostigma chlaroterae, Llanorella ramalinae, Nesolechia fusca, Spirographa skorinae, Tremella celata, T. parietinae, and Zyzygomyces physconiae. Molecular data further clarify the phylogenetic position of Phoma candelariellae, which forms an isolated lineage within Phaeosphaeriaceae. We introduce the new genus Phomella and provide a new combination, Phomella candelariellae. Several previously unknown host associations are documented, including Calogaya saxicola as a new host for Chaetopyrena penicillata; Cetraria aculeata for Cladosporium licheniphilum; Circinaria hispida, Xanthoparmelia camtschadalis, and X. pokornyi for Didymocyrtis cladoniicola; Xanthoria monofoliosa for Didymocyrtis epiphyscia; Xanthoparmelia camtschadalis for both Epithamnolia xanthoriae and Nesolechia fusca; and Xanthoria parietina for Protocreopsis globulosa. Plowrightia mereschkowskyi is considered a new synonym for Arthonia urceolata.
The new monotypic genus Arneparmelia is introduced on the basis of phylogenetic and phenotypic evidence. The new combination, A. skultii, is proposed. Phylogenetic analyses using nuITS, nuLSU, mtSSU, and mcm7 markers place the new genus close to Parmelia and Notoparmelia, although relationships among these genera remain incompletely resolved. The distinction between these three lineages as separate genera is also reflected in their morphological, chemical and geographical differences. Arneparmelia is characterized by a foliose, dark brown to black thallus with a black, stiff rim around the lobes, the upper surface covered by a bluish-white to lilac pruina and with silver, marginal or rarely laminal pseudocyphellae and by the presence of norstictic acid in high concentrations. The thalli of most species belonging to Parmelia and Notoparmelia exhibit a range of grey shades. The presence of a black margin is rarely observed and is found in only a few Parmelia species, and it is always absent in Notoparmelia. The pruina is always absent in Notoparmelia, and, when it is present in Parmelia species, its color is white. The presence of norstictic acid is rare and it is never present in high concentration in Parmelia and the substance is absent in Notoparmelia. The distribution of Arneparmelia is predominantly Arctic-Alpine. Species of the genus Parmelia are widely distributed, but Notoparmelia occurs in the Southern Hemisphere.
