Bulbophyllum planiplexum J.J.Verm., Nordic J. Bot. 26 (2008) 180, fig. 27
Type: Jongejan cult. 1688 (holo L), from PNG
Roots sprouting near the base of the rhizome, growing backwards along it until reaching the substrate. Rhizome up to 12 cm long, c. 2 mm in diameter, sections between pseudobulbs 1.1-1.6 cm long, patent to pendulous, bracts rather persistent. Pseudobulbs 1-1.6 by 0.7-0.9 cm, obliquely recurved, distant, oblong, deeply furrowed on the adaxial side with the edges clasping the next shoot, the new shoot arising at the base of the pseudobulb. Leaves sessile, blade 2.3-5.7 by 1.5-2.1 cm, index (length/width) 1.3-2.7, elliptic-ovate, acute. Inflorescence 4.5-5 cm long, 1-flowered; peduncle c. 1.5 cm long, porrect; non-floriferous bracts 2, the longest 6-7 mm long; floral bract c. 4.5 mm long, tubular, acute. Flowers moderately opening. Pedicel-with-ovary c. 14 mm long, basal node on a c. 5.5 mm long stump. Dorsal sepal c. 8.3 by 2.5 mm, index c. 3.3, porrect, ovate, acute, margins entire, base broadly attached, rather thick, surface glabrous. Lateral sepals c. 8.3 by 2.4 mm, index 3.4-3.5, free, ovate-triangular, base broadly attached, otherwise as the dorsal sepal. Petals c. 2 by 1.2 mm, index 1.6-1.7, porrect, ovate, with an obtuse edge along the lower margin, obtuse, margins finely papillose distally, base narrowly attached, rather thin, surface glabrous. Lip c. 6 by 1.1 mm, index 4.4-4.5, somewhat recurved at a quarter of its length, triangular, obtuse, margins distinctly and stiffly ciliate except near the base, thick; adaxially concave in the proximal quarter of its length, with two short, obtuse ridges starting at the margin and slightly converging, surface convex distally, glabrous; abaxially convex, deeply furrowed distally, surface long and stiffly hairy except near the base. Column c. 1.8 mm long; stigma elliptic, without keels inside, with two small, conical, obtuse teeth just below its proximal margin; foot widened and with patent, rounded lateral teeth just above the ligament; stelidia c. 1 mm long, triangular-subulate, acute; rostellum not protruding; anther-cap abaxially with a crest overtopping the front margin, surface finely papillose, front margin not drawn out; pollinia 4, more or less ovoid, all moderately flattened, the inner slightly shorter than the outer; no appendages. (After Vermeulen, 2008)
Colours: , yellow, sepals with three red nerves, petals with a small red patch at the tip, lip reddish purple, but yellow with small reddish purple dots near the base, and pale yellow near the tip, column with a red patch below the proximal margin of the stelidia.
Distribution: Malesia (New Guinea).
Distribution in New Guinea: Papua New Guinea; Papua New Guinea; see map 96-2345M.jpg.