Bulbophyllum chrysanthum J.J.Verm., Nordic J. Bot. 26 (2008) 183, fig. 29
Type: Leiden cult. 20030151 (holo L), from PNG, Woitape
Roots sprouting near the base of the rhizome, growing backwards along it until reaching the substrate. Rhizome up to 40 cm long, 2-2.5 mm in diameter, sections between pseudobulbs 0.6-1 cm long, erect to patent, bracts not persistent. Pseudobulbs 0.9-1.3 by 0.3-0.45 cm, porrect, distant, cylindrical-obovoid, the new shoot arising 5-7 mm from the base of the pseudobulb, about half-way along its length. Leaves: petiole 0.1-0.2 cm long; blade 2.9-3.4 by 0.9-1.1 cm, index (length/width) 2.6-3.8 (elliptic-)ovate, acute. Inflorescence c. 1.2 cm long, 1-flowered; peduncle c. 0.4 cm long, porrect; non-floriferous bracts 2, the longest c. 3.8 mm long; floral bract c. 3 mm long, tubular, acute. Flowers moderately opening. Pedicel-with-ovary c. 4.5 mm long, basal node on a c. 1 mm long stump. Dorsal sepal c. 7 by 3 mm, index 2.3-2.4, somewhat recurved, ovate, acute, margins entire, base rather broadly attached, rather thick, surface glabrous. Lateral sepals c. 7.5 by 4 mm, index c. 1.9, free, otherwise as the dorsal sepal. Petals c. 3 by 1.5 mm, index c. 2, porrect, ovate with the lower margin somewhat curved outwards proximally, margins finely erose and papillose, base rather narrowly attached, rather thin, surface glabrous. Lip c. 5 by 1.7 mm, index c. 2.9, only slightly recurved, more or less elliptic, rounded to obtuse, margins with two antrorse, ovate, obtuse auricles at a third of the length of the lip, otherwise glabrous, thick; adaxially concave and furrowed in the proximal one third, slightly convex elsewhere, surface glabrous; abaxially with a low, flat median ridge proximally, more or less flat and somewhat furrowed distally, surface finely and rather densely shortly-hairly starting at one fifth of the length of the lip and continuing up to three fifths of its length, otherwise glabrous. Column c. 5 mm long; stigma oblong, without keels inside; foot somewhat widened and with slight, patent, rounded lateral teeth just above the ligament; stelidia c. 2.5 mm long, triangular, acute; rostellum distinctly protruding; anther-cap abaxially with a crest proximally, surface papillose, front margin drawn out into a rounded beak; pollinia 4, more or less obovoid, all moderately flattened, the inner slightly shorter than the outer; no appendages. (After Vermeulen, 2008)
Colours: Ochre-yellow, sepals with three brownish nerves, petals with one as well as a blackish purple tip, lip slightly darker brownish yellow along the mid-nerve and at the auricles, column pale yellowish green.
Flowering time in the wild: December.
Distribution: Malesia (New Guinea).
Distribution in New Guinea: Papua New Guinea; Papua New Guinea; see map 96-2273M.jpg.