Cladonia rubrotincta Vtípilová, Timdal, Resl & Steinová

A recently described species that was previously misreported from the Czech Republic under the name of the closely related C. norvegica. Cladonia rubrotincta is best distinguished from it (and from other similar species) by conspicuous red spots on the primary thallus (basal squamules), more rarely also on the podetia. The red coloration is associated with the production of rhodocladonic acid, which appears as a response to thallus damage, primarily in connection with the activity of oribatid mites (Oribatida). Molecular evidence from the red spots has confirmed mainly species of the genus Carabodes.

Cladonia rubrotincta is macroscopically similar to the common C. coniocraea, but – besides the red spots – also differs chemically: it contains barbatic and 4-O-demethylbarbatic acids (UV± blue). However, this basic chemistry is shared with both C. macilenta var. bacillaris and C. norvegica; the latter species, however, has not yet been reliably confirmed from the Czech Republic.

It occurs in communities of other Cladonia species on decaying wood of stumps and logs. It is also found at bases of trees (especially conifers) and only rarely extends onto humus or mossy rock outcrops. Cladonia rubrotincta prefers mixed or coniferous stands with an ample supply of rotting wood. It grows both in old-growth, near-natural forests and in managed stands (especially spruce forests). It is mainly a boreo-montane lichen with a slightly oceanic tendency, recorded from a number of mountain ranges and uplands in the Czech Republic. The richest Czech populations occur in the Šumava Mountains. It also occurs, though rarely, at mid elevations (e.g. in the Třeboň Basin). In Central Europe it should be regarded as a rather rare species. Its overall distribution is still poorly known; the lichen has been confirmed from Europe and North America.

Literature: Vtípilová V., Timdal E., Stodůlková E., Semerád J., Resl P. & Steinová J. (2025): Cladonia rubrotincta, a new species distinct from C. norvegica. – The Lichenologist 1–13. Pfingstl T., Vtípilová V., Ghlimová H., Mourek J., Steinová J., Schäffer S. & Resl P. (2025): Oribatid mite fauna of three members of the lichen genus Cladonia in Europe – observations on species richness, endophagous juveniles and their morphology. – Acarologia 65: 1092–1123. Malíček J., Bouda F., Kocourková J., Palice Z. & Peksa O. (2011): Zajímavé nálezy vzácných a přehlížených dutohlávek v České republice. – Bryonora 48: 34–50.

Ascomycota → Lecanoromycetes → Lecanorales → Cladoniaceae → Cladonia