Ombrophilous lichen communities of siliceous rock surfaces in the lowland to upper montane belts
rhi01 | The name Physcietalia was used in Šmarda (1947) to accommodate the highly nitrophilous Xanthorion parietinae Ochsner ex Šmarda 1947 (nom. inval; ICPN art. 3d) and the non-nitrophilous Parmelion conspersae Hadač in Šmarda 1947. Because the 'Xanthorion parietinae Ochsner ex Šmarda 1947' is invalidly published, the 'Parmelion conspersae Hadač in Šmarda 1947' is the nomenclatural type of the 'Physcietalia Šmarda 1947'. As the only Physcia species in the original diagnosis of the order is P. sciastra, the name can be completed with the taxon epithet to Physcietalia sciastrae Šmarda 1947 (ICPN Rec. 10C). Physcia is a genus of highly nitrophilous species and applying the name Physcietalia sciastrae for non-nitrophilous lichen vegetation would become a source of misunderstanding (nomen ambiguum; ICPN art. 36) and therefore we suggest the rejection of the name Physcietalia sciastrae Hadač in Šmarda 1947 in favour of a well established name. The name Rhizocarpetalia Klement 1950 is indeed well established, however it is a younger homonym of the Rhizocarpetalia Klement 1949, that we propose to conserve. The lectotypus hoc loco of the Rhizocarpetalia Klement 1949 is the Acarosporion fuscatae Klement 1949 in Klement (1949: 12). (HB).