Anatomia foliar de Maytenus Mol. emend Mol. (Celastraceae), ocorrente no Estado do Rio de Janeiro, Brasil

Abstract

This paper describes anatomical approaches to study the Genus Maytenus Mol. Emnd. Mol. (Celastraceae). The genus is the largest in the family Celastraceae, and in Brazil is represented by approximately 80 species. Maytenus is a polyphyletic genus and additional research is required to better understand its taxonomy. Maytenus ardisiaefolia Reiss., M. brasiliensis Mart., M. cestrifolia Reiss., M. communis Reiss. and M. obtusifolia Mart. are difficult to identify because of similarities in their reproductive structures and variations in the size and shape of their leaves. The anatomical structures observed within various parts of the leaves were similar in all the species studied and, as such, are of taxonomic and probably phylogenteic value for the genus Maytenus. The organisation of the epidermis and subepidermal layers in M. obtusifolia proved to be an important diagnostic character in comparison with M. ardisiaefolia. Similarly, the occurrence of acicular crystals in epidermal cells of M. communis and M. ardisiaefolia separates M. cestrifolia where crystals were not seen. These results highlight the role of anatomy as an important tool to be exploited in taxonomic studies of other species within the genus Maytenus. The observation and description of cork warts in the epidermis of the leaf blade could contribute to Celastraceae taxonomy.