LICHALP

Polyblastia rivalis (Arnold) Zschacke

Syn.: Thelidium rivale Arnold

Lichenised.

Substrate: , ,

Altitudinal range: from the montane belt (potential vegetation: deciduous forests dominated by Fagus sylvatica and closed coniferous forests with Picea abies) to the subalpine belt (potential vegetation: open, taiga-like forests dominated by Larix decidua and/or Pinus cembra and Rhododendron)

Note: a species with a whitish-grey, partly endolithic thallus, ascomata semi-immersed in pits protruding with the upper third, a dark exciple and a descending involucrellum, and submuriform, ellipsoid, relatively large ascospores (to 75 µm long) with 3-6 transversal septa and (partly) a single, incomplete longitudinal septum; on periodically inundated limestone or calcareous schists; only known from the Eastern Alps (Austria) but likely to occur elsewhere in the Alps.