A tiny, inconspicuous lichen from the M. prasina group, described recently from the Netherlands and Poland (van den Boom et al. 2017). It resembles the tiny forms of the unrelated M. denigrata by the dark fruiting bodies and pycnidia attached to the indistinctive thallus. Phylogenetically closest is another, also similar, less known species M. nowakii. Potentially, the species could be confused also for other taxa from M. prasina agg., which may form pigmented apothecia (e.g. M. fallax and M. melanobola) and whose epixylic thallus is hidden under the mucilaginous algae cover. However, M. herbarum differs from all the other mentioned species in the absence of lichen substances, smaller size and differences is spores or mesoconidia morphology.
It is a pioneer species that grows on decaying wood (most reports), plant detritus and soil often covered by colonies of non-symbiotic green algae. The lichen is probably widespread but overlooked. First report on its occurrence in the Czech Republic, from the Křivoklát region, has been published recently (Vondrák et al. 2022) and so far, it is known only from a few other localities in the country.
Literature: van den Boom P. P. G., Brand A. M., Coppins B. J. & Sérusiaux E. (2017): Two new species in the Micarea prasina group from Western Europe. – Lichenologist 49: 13–25. Vondrák J., Svoboda S., Malíček J., Palice Z., Kocourková J., Knudsen K., Mayrhofer H., Thüs H., Schultz M., Košnar J. & Hofmeister J. (2022): From Cinderella to Princess: an exceptional hotspot of lichen diversity in a long-inhabited central-European landscape. – Preslia 94: 143–181.taxonomic classification:
All records: 4, confirmed 4. One click on a selected square displays particular record(s), including their source(s).