Micromorphological traits of the leaf surface in species of the genus Sansevieria Thunb. s.str. (Asparagaceae)

This study investigated the leaf surface micromorphology of 12 species of the genus Sansevieria using light microscopy and scanning electron microscopy. The research focused on identifying micromorphological traits associated with plant stress tolerance, including epidermal cell shape, cuticle thickness, stomatal distribution and density, and cuticular characteristics with epicuticular wax deposits. In most of the studied Sansevieria species, the leaves are amphistomatic, whereas hypostomatic leaves are observed in S. cylindrica, S. canaliculata, and S. suffruticosa. In all studied taxa, the epidermis consists of a single layer of cells and lacks trichomes.The examined Sansevieria species are characterized by a well-developed cuticular layer and the presence of wax deposits that perform protective and water-conserving functions. The thickness of the cuticle and its ornamentation vary both among species and between leaf surfaces within the same species. The abaxial leaf surface generally exhibits a more developed cuticle than the adaxial surface, a feature particularly pronounced in S. cylindrica, S. canaliculata, S. kirkii, S. roxburghiana, S. gracilis, S. suffruticosa, and S. intermedia. All investigated species possess anomocytic stomata. Stomatal density on the abaxial leaf surface ranged from 9 to 27 mm2 among the studied species. These interspecific variations reflect distinct strategies for optimizing water balance under arid conditions.At the level of leaf micromorphology, amphistomaty, the spatial organization of epidermal cells, the presence of a cuticular layer with epicuticular wax deposits of various configurations, differences in stomatal sunkenness and density, and the occurrence of underdeveloped stomata can be considered markers of stress tolerance in this genus. The identified micromorphological markers provide insight into the adaptive xeromorphic traits of Sansevieria and have potential applications in applied research, including biotechnological projects and phytoremediation, including green infrastructure development.