Distribution, ecology and conservation survey on the Celtis tournefortii subsp. aetnensis (Celtidaceae-Cannabaceae) populations in Sicily

Abstract

Results of research on the Celtis tournefortii subsp. aetnensis (Celtidaceae-Cannabaceae) populations in Sicily, based on the monitoring of the various nuclei distributed in the territory, are presented. In particular, two new important unpublished stations located in the southern part of the Sicani Mountains, widespread over an area of approximately 75 hectares, are reported. It is highlighted that the species, besides the lava flows of the western slope of Mount Etna (Catania province), is tied to conoids present in five other disjointed sub-ranges, often with fragmentary and relictual stations: (1) Nebrodi Mountains inland (Cesarò territory, Messina province); (2) Madonie Mountains inland (Gangi territory, Palermo province); (3) northwestern sector, in the Palermo province (Rocca Busambra); (4) southwestern Sicani Mountains (Pizzo Telegrafo, in Contrada S. Biagio and in the Caltabellotta territory, Agrigento province); (5) southeastern Sicani Mountains (S. Stefano di Quisquina at Pizzo Castelluzzo, Agrigento province). In addition to a herbarium exsiccata census, the survey led to a biological and autoecological characterization, to the definition of the current distribution, to an estimate of the number of individuals and to an analysis of its conservation status. The risk status was also assessed and the species was ascribed to the category Endangered (EN), in accordance with the B1ab(iii) and B2ab(iii) IUCN criteria.