ABSTRACT
Three sympatric species of Mandevilla were studied with the aim to increase the knowledge about the biota of inselbergs and to identify anatomical features that could be related to a high-insolation environment. Aspects common to all studied species that can be observed in transverse section and frontal view of the stems are: uniseriate epidermis; paracytic stomata; unicellular trichomes; uniseriate hypodermis with phenolic compounds and bicollateral vascular bundles. The medulla is broad in M. dardanoi and narrow in M. scabra and M. tenuifolia. Uniseriate epidermis with cuticular ridges and paracytic stomata were observed in transverse section and frontal view of the leaves. Mandevilla scabra is hypoamphistomatic and the other two hypostomatic. Angular collenchyma under both surfaces along the midrib occurs in M. dardanoi and M. scabra. The mesophyll is dorsiventral. Some of the anatomical aspects studied, particularly in the leaves of the studied species, are frequently associated with strategies that could have a role in protection against high temperatures, light levels and water stress. Among these structures, the striate cuticle, hypodermis with phenolic compounds, compact mesophyll, and prismatic crystals and druses can be listed. The anatomical data obtained provide subsidies for future research with taxonomic and ecological approaches in Mandevilla.
Key words:
anatomy; ecology; vegetative organs; subsidies for taxonomy