Bulbophyllum thelantyx J.J.Verm., Orchid Monogr. 7 (1993) 175, fig. 132
Type: Jongejan cult. 706 (holo L, also spirit 7735)
Rhizome patent, to 8 by 0.15 cm diam. Pseudobulbs ovoid, 0.2-0.4 cm apart, 2-3 by 0.4-0.6 cm, not or hardly flattened. Petiole 3-7 mm. Leaf blade ovate to elliptic, 4.5-5.6 by 0.5-0.9 cm, index 5.5-12; tip acute. Inflorescence 4.5-7 cm, 1-flowered; peduncle 3-4.3 cm. Floral bracts c. 2. the longest 0.3-0.45 cm. Floral bracts tubular, 2.2-3.8 mm; tip approximately acute. Pedice! and ovary 9-13 mm, with the node 1.3-2.5 mm from the floral bract. Flowers moderately opening. Median sepal ovate, 9-17 by 5-7 mm, index 1.8-2.6; tip acute to shortly acuminate, margins finely ciliate, thin; surface glabrous. Lateral sepals free, oblique, 10-20 by 4-6 mm, index 2.2-3.3. margins glabrous; otherwise as the median sepal. Petals triangular, 0.6-1.2 by 0.4-0.8 mm, index c. 1.5; tip acute, margins erose, thin; surface glabrous. Lip curved, general outline ovate, 2.5-6 by 2.2-3.5 mm, index l.1-1.7 (not spread); tip rounded, margins papillose or ciliate; rather thick; adaxially with an inconspicuously basal concavety, basal teeth converging, together fomling a transversely ridge, with a notch half-way, top part of the lip concave because of the distinctly curved upwards margins, median strip glabrous, papillose or ciliate towards the margins; abaxially approximately without a median ridge; surface glabrous. Column from ovary to the tip of the rostellum 1.4-2 mm; rostellum distinctly protruding; stigma slit-like, slightly protruding at its base. Column-foot with a distinct, somewhat upwards pointing, obtuse, central knob above the attachment of the lip. Anther abaxially with an inconspicuously ridge; front margin not protruding. (After Vermeulen, 1993)
Colours: Sepals yellow, sometimes with red or purple veins. Petals pale yellow. Lip yellow, sometimes with a red tip, or entirely dark red.
Habitat: Epiphyte in montane forest; 1800-2800 m.
Flowering time in the wild: January, December.
Distribution: Malesia (New Guinea).
Distribution in New Guinea: Papua New Guinea; see map 96-1830M.jpg.
Cultivation: Cool growing epiphyte, requires shaded position.