Thorn, spine and prickle patterns in the Italian flora

Spinescence refers to the presence of sharp appendages of various origins with ecological, evolutionary or biogeographic significance. This research was conducted to explore patterns and adaptive processes of thorns, spines and prickles in the Italian flora. We compiled an inventory of 401 spiny plants taking into account the following attributes: type of spinescence, family, biological form, chorotype, bioclimate and habitat. Then, we evaluated the incidence of plants with each attribute, the co-occurrence of various types of spinescence, the associations among spinescence types and biological forms and families, the structure of data across spinescence types, thermotypes and habitats. The spatial distributions and the adaptive processes of plants with various types of spinescence revealed that these patterns are driven by evolutionary, biogeographic and ecological factors, thus supporting the hypothesis that interactive processes of selective pressures and phylogenetic constraints have influenced the evolution of spinescences.