A little known representative of the genus, which is very similar to M. nigella. Some authors (e.g. Czarnota 2007) have considered these taxa as synonyms, but phylogenetically they are well-defined species. The major difference is the shorter conidia, 2.5–3.5 µm in M. melaeniza compared to 3.4–4.5 µm in M. nigella. Another difference is pigmentation, M. nigella contains brown to purplish-brown (K+ green) Melaena-red pigment in the hymenium, hypothecium and pycnidia wall. In contrast, M. melaeniza produces other pigments (see Kantelinen et al. 2024), but due to some variability, pigment-based identification may not be reliable. The situation is further complicated by the frequent absence of apothecia.
Micarea melaeniza grows on the decaying wood of conifers. So far it is known from old-growth and primeval forests in boreal and montane areas. In Europe it has so far been found only in a few countries in the northern, central and eastern parts of the continent (Kantelinen et al. 2024). In the Czech Republic it has so far been reliably documented only from the Šumava Mts and will probably be a rare lichen in the country.
The occurrence of the newly described species M. eurasiatica Kantelinen & G. Thor in the Czech Republic is possible. This taxon differs mainly in its significantly longer conidia (4.5–6.0 µm) and lower cylindrical pycnidia.
Literature: Czarnota P. (2007): The lichen genus Micarea (Lecanorales, Ascomycota) in Poland. – Polish Botanical Studies 23: 1–190. Kantelinen A., Svensson M., Malíček J., Vondrák J., Thor G., Palice Z., Svoboda S. & Myllys L. (2024): A phylogenetic study of Micarea melaeniza and similar-looking species (Pilocarpaceae) unveils hidden diversity and clarifies species boundaries and reproduction modes. – MycoKeys 106: 327–353.
taxonomic classification:Ascomycota → Lecanoromycetes → Lecanorales → Pilocarpaceae → Micarea
All records: 9, confirmed 4. One click on a selected square displays particular record(s), including their source(s).