Owing to a few unique characteristics in the anatomy of fruiting bodies, it apparently is not a member of the genus Lecidea s. str. Lecidea commaculans is relatively well-identifiable microscopically as it contains prominent burgundy red to purple pigment in the hypothecium which may be stressed by the addition of KOH. Furthermore, the species forms conspicuous charcoal black, delimited epihymenium. Paraphyses and excipular hyphae are richly branched and clearly apparent after adding KOH thanks to their gelatinous cover. The simple to one-septate tiny ascospores are often irregular, bell-like shaped.
The lichen overgrows a variety of acidic siliceous rocks, including vulcanites, and occurs mainly at higher elevations in cold screes, rock mountain valleys and open rock outcrops. It prefers moist microhabitats and may be found on both horizontal and overhanging surfaces of stones, boulders and rocks. In screes, for example, the species has been collected on low-lying stones in depressions or on overhanging surfaces of large boulders. Lecidea commaculans has begun to be recognized in the Czech Republic quite lately (Palice 1999). Although it is apparently a relatively rare lichen of relic habitats, it may also be easily overlooked in suitable biotopes and the number of its known localities is expected to slightly increase in the future.
Literature: Palice Z. (1999): New and noteworthy records of lichens in the Czech Republic. – Preslia 71: 289–336.taxonomic classification:
All records: 10, confirmed 8. One click on a selected square displays particular record(s), including their source(s).