This species was described by Hsu & Kuo (2010) from North Taiwan (endemic). It was collected in secondary forests and bamboo forests. The epitheton flexistyla derifed from its strongly incurved column, which is quite peculiar for a species in Gastrodia (Hsu & Kuo 2010). It is closely related to G. nipponica but differs in having a trilobed column with a strongly incurved central lobe, which enables self-pollination. The publication provides a detailed drawing of all flower parts. With the proposal of Clements & Jones (2019, not available in Germany) of a new classification for the genus Gastrodia a transfer of this species to Demorchis was proposed.
Amendment: Gastrodia flexistyloides from Suetsugu (2014) is accepted as a separate species by WFO (2023) but treated as a synonym of G. flexistyla by POWO (2023). Because the latter authority based its decision on a paper (DOI: 10.6165/tai.2021.66.11.) which does not cover the genus Gastrodia at all, we decided to keep Gastrodia flexistyloides as a separate species.