Asplenion cuneifolii includes vegetation of serpentine rock outcrops. Serpentine is an ultramafic rock with high content of magnesium and heavy metals, which exert toxic influence on many plant species. Some ferns are confined to this habitat, namely Asplenium adulterinum and A. cuneifolium. The southern European fern species Notholaena marantae, which reaches its northern limits in central Europe, also rarely occurs on serpentine outcrops in warm areas of this region. In the Czech Republic, occurrences of serpentine are found in small patches in different areas of the Bohemian Massif. Along with specialist ferns, serpentine outcrops host mainly species from the adjacent forests or grasslands: in precipitation-rich areas, most of these are calcifuge species, while in drier areas, calcicoles strongly prevail.