Abstract
Orchidaceae is the largest family of vascular plants and is a group under intense threat due to anthropic activities. Cattleya caulescens and C. endsfeldzii are endemic rupiculous species of Minas Gerais state, Brazil, and listed on Red Lists of endangered species at state and national levels. We conducted morphoanatomical studies with the vegetative organs of the two species, with the objective of increasing knowledge of these taxa, considering the potential that these studies represent in the management of species. Cattleya caulescens and C. endsfeldzii show strong morphoanatomical similarities, which corroborates with previous studies that include both species in the same section of the genus. Many anatomical features described here (presence of single-layered epidermis, stomata only on the abaxial side of the leaf, large primary pit fields in the chlorophyll parenchyma and root anatomy) are common to several other species of Orchidaceae. The xeromorphic features observed in C. caulescens and C. endsfeldzii are related to edaphoclimatic conditions, since they grow on rocky substrate, in constant exposure to solar light and severe water restriction during most of the year. This work contributes to increase the knowledge about Cattleya genus and to support in the taxonomic delimitation of these endangered species occurring in areas of intense antropic activity.
Key words:
endangered species; morphoanatomy; orchids
