Dendrobium tubiflorum J.J.Sm., Bull. Jard. Bot. Buitenzorg, sér. 2, 13 (1914) 66; Nova Guinea 12, 3 (1916) 348, t. 127, fig. 232.
Type: Pulle 1118 (syn BO, isosyn L); 1189 (syn BO).
Stems crowded, unbranched, 40 cm long, internodes 1.6-2.5 cm long. Leaf sheaths when dried with prominent veines. Leaves patent, twisted at the base so as to lie in one plane, subovate-lanceolate, 6.25-10 by 1.9-2.6 cm, rigidly papyraceous, apex acuminate, mucronate, with a filiform apicule. Inflorescences racemose, 0.7-1.1 cm long, sessile, 6-10-flowered. Floral bracts broadly subovate, 0.8 cm long, apex long acuminate. Pedicel 3.3 cm long; ovary 1.1 cm long, clavate, obtusely triangular in cross-section. Flowers 3 cm long. Dorsal sepal 0.7 cm by 4.3 mm; mentum subcylindrical, 2.4 cm long. Petals 0.63-0.65 cm by 3 mm, margins near apex very minutely erose. Lip much shorter than the column, when flattened 2 by 0.83 cm, claw adnate to the column-foot for 1.25 cm, at c. 1/3 above the base with a transverse thickening, apex cucullate, in the middle fimbriate. Column 0.25 cm long; column-foot 2.4 cm long.
(after Smith, 1916).
Colours: Flower light rose-violet, lip almost white. A form with all-white or pale yellowish green flowers is known (f. albidiflorum).
Habitat: Epiphyte in primary and secondary montane forest. Altitude 1200 to 1300 m.
Flowering time in the wild: February.
Distribution: New Guinea (endemic).
Distribution in New Guinea: Papua (Oroh Valley).
Notes: Dendrobium tubiflorum is very similar in habit to Dendrobium lawesii, but appears to be distinct by the lip being much shorter than the column, while in D. lawesii the lip extends to the apex of the column.
Cultivation: Intermediate growing epiphyte.