Abstract
This study reports the floristic survey of Orchidaceae occurring in 125 forest fragments distributed among 23 counties of the central region of São Paulo state, Brazil. In this region, the family is characterized by 219 species distributed in 96 genera. Individuals collected in the vegetative state were maintained in a greenhouse until flowering. The majority of species (64%) are epiphytes, while 35% are terrestrial, 14.6% are rupicolous, two (0.9%) are hemi-epiphytes and one is mycoheterotrophic (0.4%). Acianthera (13 spp.), Habenaria and Gomesa (12 spp.), and Epidendrum (11 spp.) are the most representative genera. Of the unidentified species, four are possibly new to science: Anathallis sp., Baskervilla sp., Pelexia sp., Triphora sp. Furthermore, a new combination for the genus Gomesa R.Br. is presented. The central portion of São Paulo state is an ecotone between Brazilian Savanna and Atlantic Forest with a high number of species from both formations. Many species (44.7%) are rare in the study area and are threatened due to anthropogenic disturbance and indiscriminate collecting of orchids.
Key words:
Savanna; ecotone; Atlantic Forest; floristic survey