Brachypodium rupestre (Host) Roem. & Schult. herbaceous communities of heliophilous edge in the Trifolio medii-Geranietea sanguinei Müller 1962 class

This phytosociological study defines the heliophilous edges dominated by Brachypodium rupestre of different areas of central-southern Italy, from a lower Supratemperate thermotype to a lower Mesotemperate thermotype. This has allowed the description of four new syntaxa of the order Asphodeletalia macrocarpi that help to extend its biogeographic, bioclimatic and landscaping areal distribution. In particular, for the Supratemperate thermotype of the Apennine limestone areas, two new associations are recognized: Tanaceto corymbosi-Brachypodietum rupestris and Laserpitio siculi-Brachypodietum rupestris, which are included in the suborder Senecio scopolii-Brachypodienalia genuensis and alliance Luzulo sieberi- Brachypodion genuensis. For the sub-Mediterranean areas, the new suborder Dorycnio herbacei-Brachypodienalia rupestris (order Asphodeletalia macrocarpi) is proposed, with the new alliance Dorycnio herbacei-Brachypodion rupestris as the typus. The two new associations, Galio erecti- Brachypodietum rupestris (ass. typus) and Bituminario bituminosae-Brachypodietum rupestris can be referred to this new alliance. The new suborder Dorycnio herbacei-Brachypodienalia rupestris groups together the heliophilous, mesophilous and anthropogenic edges, dominated by Brachypodium rupestre of the Mesotemperate thermotype of subcoastal, pre-Apennine and infra-Apennine sub-Mediterranean territories of central and southern Italy. The optimum development of this new suborder is on non-calcareous lithologies and deep soils, in dynamic link with the grasslands of Polygalo mediterraneae-Bromion erecti, where Brachypodium rupestre is a transgressive species. Dorycnio herbacei-Brachypodienalia rupestris is vicarious in the sub-Mediterranean areas, with the calcareous Apennine suborders Senecio scopolii-Brachypodienalia genuensis and Asphodelenalia macrocarpi. This study of the dynamic and chain contacts has made it possible to define the ecological position of the plant communities described here, and to clarify the reference dynamic landscape and complete the main landscape units described for central-southern Italy. On the basis of these analyses it is possible to define for central and southern Italy three suborders of the order Asphodeletalia macrocarpi: Asphodelenalia macrocarpi (suborder typus) for the heliophilous edges with Asphodelus macrocarpus of the Supratemperate thermotype of the Apennine sector; Senecio scopolii-Brachypodienalia for the calcareous communities with Brachypodium genuense/Brachypodium rupestre dominant for the Supratemperate thermotype; and Dorycnio herbacei-Brachypodienalia rupestris for the heliophilous edges with Brachypodium rupestre dominant for the sub-Mediterranean subcoastal, pre-Apennine and infra-Apennine territories.