Plagiostachys Ridley
Leaf: shape: lanceolate, linear
Leaf: other characteristics: ligule 2-lobed
Bracts or bracteoles: margin entire or fimbriate, bracteoles tubular
Inflorescence: conical,arising from rhizomes on peduncle clothed with scalelike sheaths, breaking through leaf sheaths
Calyx: tubular, apex 3-lobed or 3-toothed, split on 1 side
Corolla: shorter or equalling calyx
Corolla lobes: ovate-oblong, central lobe erect,hooded or concave
Labellum: oblong or spatulate, entire, apex lobed or cleft or concave or emarginate
Stamens or staminodes: lateral staminode toothlike or subulate
Filament: short or absent
Anther: linear or oblong, apex emarginate
Connective: without appendage
Style: stylodes short or absent
Fruit: brittle
Seed: angled