Bulbophyllum ortalis J.J.Verm., Orchid Monogr. 7 (1993) 167, fig. 121
Type: Jongejan cult. 1275 (holo L)
Rhizome creeping, 0.8-1.2 mm diam. Pseudobulbs ovoid to ellipsoid, 0.2-0.4 cm apart, 0.5-0.9 by 0.2-0.6 cm, not or hardly flattened. Petiole 2-5 mm. Leaf blade elliptic, 0.9-3.5 by 0.4-0.7 cm, index 2-5; tip acute. Inflorescence 7-9 cm, 1-flowered; peduncle 5.5-7 cm. Floral bracts c. 3. the longest 0.4 cm. Floral bracts tubular, 0.18-0.2 cm; tip acuminate. Pedicel and ovary 10-13.5 mm, with the node 1.3-1.8 mm from the floral bract. Flowers moderately opening. Median sepal ovate, 12-22 by 4.5-6 mm, index 2-4.4; tip long acuminate, margins finely papillose, thin; surface glabrous. Lateral sepals free, oblique, 12-24 by 5-6 mm, index 2-5; otherwise as the median sepal. Petals ovate, 0.6-1.2 by 0.8-1 mm, index 0.6-1.3; tip obtuse to acute, thin, glabrous. Lip distinctly curved, general outline subtriangular with a protrusion on the longest side, 3-3.5 by 3 mm, index 1-1.2 (not spread); tip rounded, margins locally slightly papillose or with long papillae; rather thin; adaxially with the basal concavety no several than a impression, basal part of the lip with a distinct, backwards projecting, high, obtuse, glabrous median ridge, passing approximately gradually into the top part of the lip, top part of the lip convex, approximately glabrous to densely covered with elongated papillae; abaxially approximately without a median ridge; surface papillose towards the tip. Column from ovary to the tip of the rostellum 1.3-2 mm; rostellum distinctly protruding; stigma slit-like, slightly protruding at its base. Column-foot with a small, sharply upwards pointing, obtuse, central knob above the attachment of the lip. Anther abaxially with a ridge; front margin protruding. (After Vermeulen, 1993)
Colours: Sepals yellow or yellowish brown, veins and, margins reddish purple. Petals white. Lip yellow or yellowish brown base, stained with purple, top part often bright yellow.
Habitat: Epiphyte in montane forest; 1700-2000 m.
Flowering time in the wild: November, December.
Distribution: Malesia (New Guinea).
Distribution in New Guinea: Papua New Guinea; see map 96-1320M.jpg.
Cultivation: Cool growing epiphyte.