Article

Lista atualizada das Orchidaceae do Distrito Federal

Acta Botanica Brasilica 01/2003; DOI: 10.1590/S0102-33062003000200003
Source: DOAJ

ABSTRACT É apresentada a relação atualizada de Orchidaceae para o Distrito Federal (DF), a unidade da federação onde se situa a capital brasileira, localizada no centro do país. São reconhecidos 72 gêneros e 254 táxons (246 espécies e oito táxons subespecíficos), dos quais 17 (6,7%) são conhecidos apenas localmente. Os gêneros mais significativos no DF são Habenaria (74 espécies e três táxons subespecíficos), Cyrtopodium (17 espécies), Cleistes (13 espécies) e a subtribo Spiranthinae (11 gêneros com 34 espécies e dois táxons subespecíficos). Gêneros como Epidendrum (oito espécies), Pleurothallis (sete espécies), Oncidium (seis espécies) e Maxillaria (três espécies) são abundantes na Mata Atlântica no sudeste brasileiro, mas pouco representados na região. Cerca de 73% das Orchidaceae do DF apresentam hábito terrestre, o que contrasta marcadamente com a Mata Atlântica e a região Amazônica, onde predominam espécies epifíticas. Dentro do Cerrado, o DF representa o local mais bem amostrado e com o maior número de espécies conhecidas, compreendendo cerca de 51% das orquídeas listadas para todo o bioma. Esta relação tem como objetivo subsidiar a monografia desta família para a flora do Distrito Federal.

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