Bulbophyllum colliferum J.J.Sm., Bull. Jard. Bot. Buitenzorg, sér. 2, 2 (1911) 17
Type: Bogor cult. (Lorentz Exp., Rachmat) s.n. (hill near Alkmaar) (holo BO)
Rhizome erect to pendulous, up to 100 cm long, 2.5-5 mm diam. Pseudobulbs ovoid, 2-4.2 cm apart, 20-55 by 0.5-0.8 cm, hardly flattened. Petiole 1-5 mm. Leaf blade ovate to elliptic, 3.8-10.2 by 0.7-1.5 cm, index 5.5-8, tip (sub)acute. Inflorescence 1.5-3.5 cm, 2-5-flowered. Peduncle 0.7-1.3 cm; bracts 4-5, the longest 5-10 mm. Rachis 0.3-1.7 cm. Floral bracts ovate, 3-8 mm, tip acute. Pedicel and ovary 2-4 mm, with the node c. 1 mm from the floral bract. Flowers hardly to moderately opening. Median sepal ovate to elliptic, 4-6.8 by 2-3 mm, index 1.7-2.5, tip acute; thick; glabrous. Lateral sepals free, ovate, 4.3-7 by 1.5-3 mm, index 1.4-3.3, otherwise as the median sepal. Petals oblique, ovate to elliptic, 1.2-2 by 1.2-2 mm, index 0.9-1.5, tip rounded to acute; margins glabrous to finely papillose; rather thick; surface glabrous. Lip curved, general outline (ob)ovate to approx. rectangular, 0.8-1.3 by 0.6-1 mm, index 1-1.3 (not spread), tip rounded; margins finely to coarsely papillose; thick; adx. without a basal concavity, basal teeth a very inconspicuous transverse ridge, basal part of the lip slightly concave, glabrous or papillose, gradually passing into the flat or convex, almost glabrous to coarsely papillose top part of the lip; abx. without a median ridge, surface approx. glabrous. Column from ovary to the tip of the stelidia 0.7-1 mm; rostellum not protruding; stigma obovate, not protruding at its base; column-foot approx. without accessories. Stelidia inconspicuous, triangular, tip obtuse to acute. Anther abx. with a ridge; front margin hardly protruding. (After Vermeulen, 1993)
Colours: Sepals and petals white or cream-coloured. Lip white, cream-coloured, orange or red.
Habitat: Epiphyte in lowland forest; 400-2340 m.
Flowering time in the wild: May, November, December.
Distribution: Malesia (New Guinea).
Distribution in New Guinea: Papua (Indonesia); Papua New Guinea; see map 96-370M.jpg.
Cultivation: Warm growing epiphyte.