Dendrobium chalmersii F.Muell., S. Sci. Rec. 2 (1882) 96 (publ. May 1882).
Type: Chalmers s.n.
Stems erect, slender, 40-80 cm by 10 mm, upper part more slender, leafy in apical half. Leaves linear-lanceolate, c. 10 by 3 cm, pergamentaceous, apex unequally bilobulate, the longer lobule obtuse. Inflorescences from the upper part of the stem, racemose, patent, 8-10 cm long, 5-12-flowered. Floral bracts linear, about as long as the pedicel with ovary. Flowers 2-3 cm long. Dorsal sepal reflexed, ovate, apex acuminate. Lateral sepals twisted; mentum short, obtuse. Petals a little shorter than the dorsal sepal, linear, spirally twisted, margins serrulate. Lip 3-lobed in the middle, with 3 keels, these at the base fused into a solid backwards pointing appendage; lateral lobes erect, rhombic; midlobe transversely oblong, undulating.
(largely after Kraenzlin, 1910 - as Dendrobium cincinnatum, and Lavarack et al., 2000).
Colours: Sepals and petals creamy white, lip ochrish yellow, with purple veins on the lateral lobes.
Habitat: Epiphyte in rainforest. Altitude 0 to 500 m.
Flowering time in the wild: April, May, August, September.
Distribution: New Guinea, Lousiades.
Distribution in New Guinea: Papua New Guinea (Milne Bay Province: D'Entrecastaux Archipelago and Louisiades).
Notes: The spirally twisted petals of Dendrobium chamersii suggest section Spatulata, but the papillose roots and the lip with a basal appendage firmly place this curious orchid in section Brevisaccata.
Cultivation: Warm growing epiphyte, needs watering throughout the year.