Ecological niches and climate-driven range shifts in Hemorrhois snakes: implications for biogeography

Understanding the factors shaping species distributions is essential for predicting their responses to environmental change. The genus Hemorrhois (horseshoe whip snakes) comprises ecologically diverse colubrid snakes found across the Mediterranean Basin, North Africa, the Middle East, and Central Asia. Despite this broad range, their ecological niches and distributional dynamics remain understudied. This study employs ecological niche modeling (ENM) to assess the biogeography, niche differentiation, and potential climate-driven range shifts of H. algirus, H. hippocrepis, H. nummifer, and H. ravergieri under future climate scenarios. Using species occurrence data and bioclimatic variables, I constructed ensemble models to predict suitable habitats, evaluate niche overlap, and quantify potential range changes. Results indicate significant variation in climate-driven distributional responses among species. Hemorrhois algirus is projected to expand across North Africa, whereas H. hippocrepis, H. nummifer, and H. ravergieri may face range contractions under high-emission scenarios. Niche analyses suggest moderate overlap between H. algirus and H. hippocrepis, implying historical and ecological connectivity, while H. nummifer and H. ravergieri display distinct environmental preferences. Climatic and geographic barriers—such as the Sahara Desert, the Dardanelles and Istanbul Straits, the Alps, and the Pyrenees Mountains—play crucial roles in shaping their evolutionary trajectories. Given the increasing threats of climate change and habitat loss, this study underscores the need for conservation strategies prioritizing habitat connectivity, species-specific management, and climate refugia. By integrating ecological and evolutionary perspectives, this research contributes to understanding Mediterranean and Western Palearctic reptile biogeography and their responses to environmental change.