Dendrobium atropurpureum (Blume) Miq., Fl. Ned. Indië 3 (1859) 644.
Basionym: Oxystophyllum atropurpureum.
Stems sometimes branching, 10-45 cm long, many-leaved. Leaves erect-patent, straight to subfalcate, ensiform, 5-6.3 cm long, carnose, apex very sharply acute. Inflorescences arising from between the leaves, sessile. Floral bracts ovate, apex acuminate. Sepals oblong, slightly keeled, apex acute. Petals smaller than the dorsal sepal. Lip spathulate-oblong, longer and more fleshy than the sepals, swollen towards the middle, below near the apex with an acute wart, lateral margins thinner, recurved, minutely erose, apex retuse. Fruit ellipsoid, almost triangular in cross section.
Colours: Flower purple.
Habitat: Epiphyte in coastal forest.
Flowering time in the wild: Not recorded.
Distribution: ?Moluccas, New Guinea.
Distribution in New Guinea: Papua.
Notes: Dendrobium atropurpureum will probably turn out to be a widespread species, once the species of section Oxystophyllum have been clarified.
Cultivation: Warm growing epiphyte.