Vegetative Anatomy of Aspleniaceae Newman from Brazilian Atlantic rainforest and its application in taxonomy

- The anatomy of species of Asplenium and Hymenasplenium were compared.
- The distribution of meristeles is an important character for the segregation between Asplenium and Hymenasplenium.
- Characters of petiole and presence of crystals and trichomes at lamina are useful for delimitation of Asplenium species.

Several studies have demonstrated the usefulness of anatomical characters for the taxonomy of Aspleniaceae. However, works on the anatomy involving Brazilian species are scarce. With the objective to fill out such a gap, the vegetative anatomy of Aspleniaceae species occurring in Brazil was studied in order to verify the efficiency of the anatomical characters of the root, rhizomes, and frond for taxonomic segregation. Survey was carried out in 20 Aspleniaceae species. Epiphytic, terrestrial and rupicolous species were analyzed. The anatomy showed to be a good source of information for the taxonomy of the group, revealing the presence of characters that can help the species and genera delimitation. The presence of sclerenchyma with thicker internal periclinal cell walls in the root and the distribution of meristeles in the stem are important segregation characters to Asplenium and Hymenasplenium. Crystals mass, trichomes, and the xylem are diagnostic for Asplenium species. An identification key was elaborated in order to apply the anatomical characters in the segregation of the species studied.