Bulbophyllum alkmaarense J.J.Sm., Bull. Dép. Agric. Indes Néerl. 45 (1911) 7
Type: Bogor cult. (Exp. Lorentz, Djibdja 667) s.n. (holo BO)
Rhizome creeping, branched, rooting. Pseudobulbs close together, moniliform, procumbent, appressed to the rhizome and in basal half adnate, with apex frequently more or less curved upwards, oblong, strongly c. 7-ribbed, 0.55-0.7 by 0.23 cm; 1-leaved. Leaf elliptic, oblong, or subovate, obtuse, or very shortly acute; base shortly contracted in a petiole; midrib above grooved, somewhat fleshy-coriaceous, c. 1.1-1.7 by 0.5-0.7 cm. Inflorescences from the nodes of the rhizome, short, 1-flowered; peduncle 0.6 cm long. Floral bract tubular, acuminate, 0.27 cm long. Flower medium size, c. 2.45 by 2.15 cm; sepals inside to base shiny. Median sepal erect, linear, subacute, 3-nerved; base convex, further channelled-concave; margins in the middle more incurved almost contracted, c. 1.4 cm long; slightly over 0.2 cm. Lateral sepals divergent, obliquely lanceolate-oblong, very shortly pointed, 3- nerved, dorsally prominent, c. 1.4 by 0.43 cm; basal part convex, further concave. Petals very small, porrect, vertical, incurved, obliquely oblong; upper part dilated; apex falcate-incurved, obtuse; upper margin strongly recurved, convex, 1-nerved, 0.34 by 0.14 cm. Lip immobile, porrect, sigmoid, spathulate, hollow-clavate, c. 1.18 cm long; base with 2 minute, oblong, obtuse, auricles, towards the column-foot falcate-recurved, glutinosum; claw linear, above 3-ribbed, the margins above strongly revolute; blade in outline when not flattened oblong, broadly obtuse, 5-ribbed, 0.7 by 0.27 cm. Column slender, strongly curved, 0.3 cm long; clinandrium strongly hollowed, on either side of the stigma finely laciniate-dentate, the lacinia subulate, widely patent. Anther cucullate, laterally compressed, obtuse, finely warty; base c. 0-05 cm long; column-foot making a straight angle with the ovary, short, triangular, 0.1 cm long. Ovary 6-grooved, pale green, 0.2 cm long; pedicel 0.8 cm long. (After Smith, 1911)
Colours: Pseudobulbs pale green. Leaf pale green. Peduncle dark purple. Median sepal somewhat translucent white, with a longitudinal, dark purple band. Lateral sepals dark purple, with a pale margin. Petals shiny, dark purple, except the upper margin and a longitudinal stripe from the base which are translucent white. Lip with golden yellow claw; blade golden yellow with dark purple apex. Column somewhat shiny, pale greenish, the base yellow, above with dark purple stripes; column-foot yellow. Anther violet with yellow base. Ovary pale green,; pedicel pale green suffused purple.
Habitat: Epiphyte in lowland forest; 300-2250 m.
Flowering time in the wild: April, October, November, December.
Distribution: Malesia (New Guinea).
Distribution in New Guinea: Papua (Indonesia); Papua New Guinea; see map 96-77M.jpg.
Cultivation: Warm growing epiphyte.