Initially described as Alpinia decurvata by J.G. Baker in 1892, this ginger was subsequently transferred to Geostachys as G. decurvata in 1899 by H.N. Ridley. Before the International Code of Botanical Nomenclature was established, citing a species as the type was not a requirement when describing a new genus. To remedy this situation in 2007 Lau, K.H. et al. chose this species as the type for the genus Geostachys.

Geostachys decurvata stands to 2.4 m tall and is supported above the ground level by thick stilt-roots. The leaves measure 48-70 × 5-10 cm and commonly reddish underneath. One would not miss the conspicuous arrangement of the flowers, which are one-sided on a decurved inflorescence. The flower, or precisely the labellum, is yellow with occasional small red spots. It has a trilobed margin with the midlobe round and broad, and the side lobes round. The mature fruits are ellipsoid, glabrous and shining maroon.

The habitat of G. decurvata is well conserved on Gunung Hijau (Maxwell Hill) due to the low number of visitors and human activities. The species is also hyper-endemic in this locality. However, because not many clumps were seen in that pristine forest, it is assessed as Endangered (EN) under the IUCN categories.