Introduction: Twenty species are known in this small genus of epiphytic or rarely terrestrial herbs. Kränzlin proposed in 1911 to reduce this genus to a section of Phreatia but Schlechter insisted in 1914 to retain it as a separate genus and most authors have agreed with this separation.
Derivation of genus name: Greek okta (eightfold), arrhen (male; stamen), in allusion to the 8 free pollinia.
Type species: Octarrhena parvula Thwaites
Phraetia angraecoides Schltr.
Characteristics of genus: Small plants with leafy stems, branching from the root base. the leaves are distichous, terete or bilaterally flattened. The lateral inflorescences carries many small dense flowers coloured yellow to white.
Number of species in New Guinea:
Species shown here: Octarrhena angrecoides
drawing by Neville H.S. Howcroft
Conservation status: not known
Octarrhena Thwaites