Micarea prasina Fr.

This, often only poorly fruiting species forms extensive thalli on a heavily decayed wood especially of conifers (spruce, fir) in rather moist forests. In old-growth forest it may also pass onto a bark at tree bases. Until recently, the taxon had been used (and partly still is) as a bin for Micarea species with finely granulated thallus containing micareic or methoxymicareic acid that form pale to dark (depending on the Sedifolia-grey pigment concentration) fruiting bodies with tiny simple or 1-septate ascospores. However, the species in sensu stricto is rather rare. It prefers moist mountain old-growth forests or first generation of managed forest replacing a primeval one with a sufficient supply of dead wood. Most of the data published from the Czech Republic needs to be revised. The forms with very dark fruiting bodies may belong to M. melanobola which is at this moment missing in the list of Czech lichen but has been reported, with an insecurity in the determination, from the old-growth forest on the Špičák hill near Třešť (Servít 1910, as Lecidea melanobola).

Literature: Servít M. (1910): První příspěvek k lichenologii Moravy. − Zprávy Kommisse pro Přírodovědecké Prozkoumání Moravy, oddělení botanické, Brno, 6: 1−83.

Ascomycota → Lecanoromycetes → Lecanorales → Pilocarpaceae → Micarea