Dendrobium longicaule

Dendrobium longicaule J.J.Sm., Bull. Dép. Agric. Indes Néerl. 39 (1910) 9; Nova Guinea 8, 3 (1911) 558, t. 91A.

Type: Bogor cult. (Lorentz Exp. (Rachmat 119)) s.n. (holo BO).

Rhizome short. Stems crowded, elongated, terete, probably much more than 65 cm long (described from incomplete material; to 150 cm according to Schlechter - as D. sarcodes), 8-9.5 mm wide, internodes 2.5-5.5 cm long. Leaf sheaths tubular, much longer than the internodes. Leaves oblong to lanceolate-elliptic, 4-10 by 1.9-3.5 cm, midvein not prominent below, apex obtuse to almost retuse. Inflorescences arising laterally from the stem, very short, 2-flowered, spathe laterally compressed. Ovary 0.6 cm long, obconical, 6-grooved. Flowers 2.3 cm across, ephemeral; sepals and petals widely patent with abruptly incurved, concave apices, rather fleshy, especially the sepals verrucose outside. Dorsal sepal oblong-linear, slightly widened to the apex, 1.55 cm by 6.5 mm, convex at the base, apex obtuse. Lateral sepals oblong-linear, falcate, 1.35 cm long, in the middle 5.5 mm wide, at the base 6.5 mm wide, obtusely keeled outside, apex obtuse; mentum 0.43 cm long, retuse. Petals spathulate, 1.4 cm long, near the base 3.5 mm wide, in upper part 5.5 mm wide, base concave. Lip 3-lobed above the middle, 0.85 by 0.65 cm, with a verrucose longitudinal keel, on either side of the keel verrucose, the midlobe papillose-muricate in the centre; lateral lobes erect, triangular, margins erose, apex obtuse; midlobe recurved, rounded-triangular, 0.33 by 0.4 cm, undulate, margins crenulate-undulate, abruptly acutely acuminate. Column thickly conical, 0.37 cm long, lateral lobules of the clinandrium short, rounded; stigma quadrangular, deeply concave; column-foot at right angles to the ovary, 0.35 cm long, straight, oblong-quadrangular, truncate. Anther cucullate, flat in front, dorsally retuse, apex truncate-rounded. Pollinia oblong.
(after Smith, 1911).

Colours: Flower yellow, sepals and petals inside and at the base outside dotted with brown, the lip with violet-brown dots and red warts inside (Dendrobium sarcodes: Sepals and petals white with red dots, the lip yellowish with an orange-red keel, and brown transverse wrinkles).

Habitat: Epiphyte in lowland rainforest and lower montane forest, also in seasonally dry lowland forest (fide O'Byrne). Altitude 100 to 1000 m.

Flowering time in the wild: February to May.

Distribution: New Guinea (endemic).

Distribution in New Guinea: Papua (Merauke Regency); Papua New Guinea (Madang and Central Provinces).

Map: LONCAMAP.JPG [Dendrobium longicaule J.J.Sm., distribution map.]

Cultivation: Warm growing epiphyte.