This work presents a floristic survey of Orchidaceae in Morro do Chapéu, municipality situated in the Chapada Diamantina, Bahia, Brazil. Fifty three species in twenty nine genera are hereby recognized. Epidendrum (five species), Gomesa (five), Encyclia (four), and Habenaria (four) were registered as the most diverse genera in the region. Morro do Chapéu had twenty five exclusive species compared with other regional surveys in the Chapada Diamantina, contributing with four new records for this area (Galeandra beyrichii, Gomesa barbata, Habenaria josephensis and Prescottia oligantha). Fifteen species listed do not occur in other compared areas of Eastern Brazil, being only distributed over the Cadeia do Espinhaço. Differences among vegetation types, territorial ranges, anthropical degrees and samples, seem to interfere with the floristic similarity of these areas. An identification key, descriptions, commentaries and illustrations of species are provided.
Chapada Diamantina; floristic; orchid; taxonomy
