Current and Potential Future Distribution of Endemic Salvia ceratophylloides Ard. (Lamiaceae)

Human activities and climate change are the main factors causing habitat loss, jeopardising the survival of many species, especially those with limited range, such as endemic species. Recently, species distribution models (SDMs) have been used in conservation biology to assess their extinction risk, environmental dynamics, and potential distribution. This study analyses the potential, current and future distribution range of Salvia ceratophylloides Ard., an endemic perennial species of the Lamiaceae family that occurs exclusively in a limited suburban area of the city of Reggio Calabria (southern Italy). The MaxEnt model was employed to configure the current potential range of the species using bioclimatic and edaphic variables, and to predict the potential suitability of the habitat in relation to two future scenarios (SSP245 and SSP585) for the periods 2021-2040 and 2041-2060. The field survey, which spanned 5 years (2017-2021), involved 17 occurrence points. According to the results of the MaxEnt model, the current potential distribution is 237.321 km(2), which considering the preferred substrates of the species and land-use constraints is re-estimated to 41.392 km(2). The model obtained from the SSP245 future scenario shows a decrease in the area suitable for the species of 35% in the 2021-2040 period and 28% in the 2041-2060 period. The SSP585 scenario shows an increase in the range suitable for hosting the species of 167% in the 2021-2040 period and 171% in the 2041-2060 period. Assessing variation in the species distribution related to the impacts of climate change makes it possible to define priority areas for reintroduction and in situ conservation. Identifying areas presumably at risk or, on the contrary, suitable for hosting the species is of paramount importance for management and conservation plans for Salvia ceratophylloides.