Gastrodiamicrochila (Orchidaceae, Epidendroideae), a new species from Brunei Darussalam.

A new orchid species, Gastrodiamicrochila is described and illustrated. The species was found in a mixed dipterocarp forest in the Belait district, Brunei Darussalam, northern Borneo in 2024. It is distinct from most Gastrodia species in western Malesia by its small lip and column, and presence of the smooth cushion-like tissue on the inner side of lateral sepals. Gastrodiamicrochila is only the second species of Gastrodia recorded for Brunei Darussalam and the seventh known species for Borneo. A determination key for all Gastrodia species occurring in western Malesia is also provided.