Distribuzione, consistenza delle popolazioni e sinecologia di Androsace brevis (Primulaceae)

Background and Aims – Androsace brevis (Hegetschw.) Ces., is a steno-endemic, exclusive to siliceous ridge environments in the central-southern Alps near Lake Como. The aim of the study is to produce a detailed map of the populations of A. brevis, to count the individuals and define their synecology, which the literature assigns to Androsacion vandellii, a category that does not correspond to what was observed in the field. Methods – The range of A. brevis was divided into 3 subareas: Luganese Pre-Alps and south-eastern Lepontine Alps (Alto Lario, central-eastern Ticino, south-eastern Mesolcina), western Orobie Alps and western Rhaetian Alps (Val Masino and Val Codera). Each sub-area was explored, identifying localities of presence and populations. Identified populations were mapped with GPS, and individuals were counted. With regards to the synecological framework, the flora present together with the pulvini of A. brevis was recorded using the phytosociological survey method. All data was recorded in special Excel databases for processing. Results – To date, more than 1’000 individuals have been counted in 5 localities in Alto Lario (one of which in Mesolcina, the others in the province of Como and Ticino), more than 800 individuals in 7 localities in the Orobian Alps and just over 50 individuals in 3 localities in the Western Rhaetian Alps. As regards the synecological analysis, 49 phytosociological surveys were carried out, which, analysed by means of cluster-analysis, revealed the presence of 5 different synecological clusters. Conclusions – The count has made it possible to produce a detailed distribution map, the most up-to-date available to date, to provide precise indications of populations at risk of extinction, and to provide basic data for other studies in progress (reproductive biology, biogeography and phylogeography). The exploration of the area is continuing, with the identification of new populations. The surveys have made it possible to better frame the phytosociological reference of A. brevis, showing its ability to adapt also to contexts that cannot be classified as Androsacion vandellii.