Diplocaulobium phalangium

Diplocaulobium phalangium (Schltr.) Kraenzl., in Engl., Pflanzenr. IV. 50. II. B. 21 (1910) 339.

Basionym: Dendrobium phalangium.

Rhizome very short, roots elongated, filiform, flexuose, glabrous. Pseudobulbs crowded, 1-leaved, slender, to the base ovoid-widened, 2-5 by 0.4-0.5 (at the base) to 0.1-0.15 cm (near the apex). Leaves oblong-ligulate, 3-6 by 0.6-1 cm, apex obtuse, unequally bilobulate, coriaceous. Inflorescences arising in succession from the apex of the pseudobulb, 1-flowered. Floral bract deltoid, minute. Pedicel and ovary 2.5 cm long, slender, glabrous. Flower resupinated, c. 4 cm wide. Dorsal sepal lanceolate, to the apex filiform-elongated, 2 cm long. Lateral sepals falcate-lanceolate, to the apex filiform-elongated, to the base abruptly widened, 2 cm long, mentum obtuse. Petals obliquely linear-lanceolate, to the apex filiform-elongated, c. 1.8 cm long. Lip weakly 3-lobed below the middle, 1.3 by 0.6 cm (in apical part), with two parallel keels extending from the base to the middle, the keels thickened distally, in front of the keels with an oblong callus; lateral lobes hardly developed, broadly rounded; midlobe suborbicular, weakly clawed, margins undulate, apex rounded. Column short, clinandrium 3-lobulate, the median lobule subulate, the laterals half as long, tooth-like, denticulate; column-foot as long as the column proper. Anther subquadrate-cucullate, glabrous, in front truncate.
(after Schlechter, 1905).

Colours: Flowers pinkish red (late anthesis?), the lip white with brown-violet veins, callus white.

Habitat: Epiphyte in lower montane forest. Altitude 800-1100 m.

Flowering time in the wild: April, September.

Distribution: New Guinea (endemic).

Distribution in New Guinea: Papua New Guinea (probably widespread; the type material from Sandaun Province: Torricelli Mountains).

Notes: This is a common and somewhat variable species, of which several later described species may turn out to be synonyms, e.g. Diplocaulobium ajoebii, Diplocaulobium aratriferum, Diplocaulobium fariniferum, Diplocaulobium gibbiferum, Diplocaulobium pulvilliferum, and Diplocaulobium recurvifolium. Diplocaulobium lageniforme is also closely related, this appears to be the earliest described species in this alliance, so its name will probably replace at least some of the ones mentioned above. The flowers, which last a single day, are white when newly opened but become reddish pink as the flowers start to wither.

Cultivation: Intermediate growing epiphyte.