An inconspicuous Rinodina whose thalli consist of just a few convex areoles around apothecia. However, apothecia are often absent. The spores have a double cell wall (Tunicata-type). Most commonly, it grows on limestone, but also on calcareous insertions or calcified surfaces of siliceous rocks (such as diabases or andesites), often around crevices. The lichen prefers well-lit sites and naturally xerothermic habitats (e.g., rocky steppes) at lower elevations. Its absent from the mountains. In the Czech Republic, R. calcarea is scattered in limestone areas (e.g., the Bohemian karst, Pálava Hills) and in river canyons in areas with basic siliceous rocks (Křivoklát and Podyjí regions).taxonomic classification:
All records: 43, confirmed 35. One click on a selected square displays particular record(s), including their source(s).