Nephroma bellum (Spreng.) Tuck.

The rarest of the three Czech Nephroma species. It grows on mossy bark of deciduous trees in moist old-growth forests and on mossy rocks. It is a boreal-montane lichen with a continental preference, widespread in the northern hemisphere but rare in central Europe, where it has been reported only from mountains (such as the Alps). In the Czech Republic, it used to occur in some of the mountain ranges (the Krkonoše Mts, Jeseníky Mts, Beskydy Mts, the Českomoravská vrchovina uplands, etc.) in the past. At this moment, only residual micropopulations persist in the Šumava Mts. The species declined mainly due to the continuous disappearance of the old-growth forests and partly also due to acid rain in the second half of the last century. Generally, the lichen is very sensitive to environmental changes. It requires well-preserved, micro- and mesoclimatically stable habitats of primaeval character.

In the past, N. bellum used to be often reported from the country under the name N. laevigatum, a suboceanic lichen of similar appearance, widespread, for example, in western and Mediterranean Europe and reaching also the Alps. The species is well-recognisable thanks to the pigmented medulla. Its (at least) historical occurrence in the Czech Republic can not be ruled out.

The poorly known N. laevigatoides Gyelnik was described based on an old exsiccated material collected by Naumann in the Šluknov region. Most probably, it is synonymous to N. bellum, but not officially yet. The problematics requires further studies.

Literature: Liška J., Dětinský R. & Palice Z. (1996): Importance of the Šumava Mts for the biodiversity of lichens in the Czech Republic. – Silva Gabreta 1: 71–81.

Ascomycota → Lecanoromycetes → Peltigerales → Nephromataceae → Nephroma