Bulbophyllum giriwoense J.J.Sm., Bull. Jard. Bot. Buitenzorg, sér. 2, 13 (1914) 71
Type: Janowsky 139 (holo BO)
Rhizome creeping, elongated, branched, terete, rooting, 0.37 cm diam.; the last internode of each shoot below the pseudobulb short, disc-shaped, almost as thick as the pseudobulb. Pseudobulbs c. 2.8 cm apart, with the rhizome forming an acute angle, elongated, compressed, linear, obtuse, in front with two grooves, in cross-section elliptic, obtusely angled, fleshy, c. 7. by 0.8 cm; 1-leaved. Leaf lanceolate, convex, coriaceous, c. 18 by 3.6 cm; base gradually narrowed and conduplicate; apex and margins recurved, obtuse; above on either side of the midrib with sunken markings; underneath the midrib obtuse, prominent. Inflorescences from the nodes of the rhizome, probably fascicled, 1-flowered; peduncle terete, c. 7.4 by 0.13 cm, with small, tubular, to the top slightly widened and keeled, acute, 0.75 cm long sheaths. Floral bract tubular, subulate-acuminate, to the top keeled, 0.88 cm long. Flower medium size, rather fleshy. Median sepal oblong-ovate, subacute, strongly concave, glabrous, c. 1.9 by 0.78 cm; base 7-nerved, reticulate-veined. Lateral sepals obliquely oblong, acute, concave, c. 1.95 by 0.7 cm; base c. 6-nerved, reticulate-veined; margins especially to the top incurved; inside at the base thickened, with the lower halves inside densely finely warty, the rest glabrous. Petals very small, oblong-obovate-elliptic, obtuse; base convex, slightly spathulate-contracted, strongly concave, above angular-concave and thickened, the 2/3rd top part inside and outside puberulous-papillose; apex slightly recurved. Lip small, mobile, curved, tongue-shaped, subobtuse, slightly over 0.5 by 0.2 cm; back obliquely hollow-truncate; basal part with erect margins, broadly channelled, with 2 low convex keels separated by a groove; along the margins on either side with a higher rib, keels in front merging into a flat band, margins and the outer ribs in basal 1/3 finely ciliate, the sides concave; underneath with two thick, convex, puberulous-papillose keels separated by a small groove. Column slightly laterally compressed, margins broadly obtuse triangular-dilated, the lower part concave, 0.57 cm long; apex truncate, the filament very short apiculate; clinandrium concave; stelidia elongated, subulate, exeeding the anther. Anther cucullate; base bilobed; thecae very small, subrotund, convex; connective large, somewhat semiglobose-thickened, in front elongated in a large, porrect, broadly oblong, rounded, convex underneath concave, papillose, in total 0.23 cm long appendage.; stigma longitudinal, oblong; column-foot making a right angle with the ovary, the apex strongly incurved and free, linear, truncate, when measured along a straight line 0.36 cm long, the lower part 0.34 cm long, the free part slightly over 0.1 cm long. Ovary 6-grooved, 0.7 cm long; pedicel c. 6 by 0.7 cm, above the base articulate. (After Smith, 1916)
Colours: Flower violet.
Habitat: Epiphyte in lowland forest.
Flowering time in the wild: July.
Distribution: Malesia (New Guinea).
Distribution in New Guinea: Papua (Indonesia); see map 96-725M.jpg.
Cultivation: Warm growing epiphyte.