Range Extensions for Two Mycoheterotrophic Orchids, Gastrodia takeshimensis and G. flexistyloides (Orchidaceae), outside their Type Locality

Abstract

During recent field surveys in the northern Ryukyus and herbarium investigations, I found several previously unknown populations of two mycoheterotrophic and cleistogamous orchids, Gastrodia takeshimensis and G. flexistyloides (Orchidaceae). They were previously considered to be endemic to Takeshima, Kagoshima Prefecture. Given that the continued discovery of new species and range extensions for known species of Gastrodia have been made from only a limited number of surveys in a small selection of sites, it is likely that more extensive surveys in the Ryukyu Islands during the flowering season could reveal much more precise data regarding the diversity and distribution of the species of Gastrodia.