Diplocaulobium sitanalae (J.J.Sm.) P.F.Hunt & Summerh., Taxon 10 (1961) 109.
Basionym: Dendrobium sitanalae.
Rhizome short. Pseudobulbs crowded, 1-leaved, base fusiform, 4-4.5 cm long, upper part very slender, laterally compressed, in front distinctly keeled, 9.5-19 cm long, in the middle 0.37, near the apex 0.58 cm wide. Leaves ligulate-lanceolate, 10-12.5 by 2-2.5 cm, coriaceous, apex broadly obtuse, shortly obtusely bidentate. Inflorescences 1-flowered, spathe acutely acuminate, 3.5 cm long. Pedicel 5.5 cm long; ovary 1 cm long. Flower c. 7 cm across. Dorsal sepal more than 4.3 cm by 6 mm (length taken from unopened bud); mentum 0.75 cm long, broadly bilobed-retuse. Petals 2.7 mm. Lip 3-lobed, 1.9 by 1.33 cm, with 2 papillose keels, between the keels pubescent; midlobe 0.83 by 1 cm. Column 0.46 cm long.
(after Smith, 1916).
Colours: Flower yellow.
Habitat: Epiphyte in lowland rainforest.
Flowering time in the wild: January.
Distribution: New Guinea (endemic).
Distribution in New Guinea: Papua (Merauke Regency: Lorentz River).
Notes: Similar to Diplocaulobium janowskyi, but with much broader leaves.
Cultivation: Warm growing epiphyte.