Bulbophyllum calceilabium J.J.Sm., Nova Guinea 14 (1929) 456, pl. 74, fig. 103
Type: Lam 1437 (holo L)
Rhizome short, creeping, branched, rooting; sheaths conspicuous covered with. Pseudobulbs making an acute angle with the rhizome, probably terete, when dried c. 2-2.5 cm long; 1-leaved. Leaf lanceolate slightly falcate-acuminate, acute; base narrowed into a channelled petiole; midrib above grooved, below prominent, when dried coriaceous, c. 12-17.5 by 1.75-2 cm. Inflorescences a rhizome, 1-flowered; peduncle thin, c. 3.5 cm long; base several small sheaths close together overlapping tubular, with. Floral bract tubular-funnel-shaped, keeled, apiculate, 0.57 cm long. Flower medium size, c. 1.4 cm long; sepals parallel, dorsally sparsely furfuraceous-punctate. Median sepal horizontal, basal part narrowly covered by the margins of the lateral sepals, lower part concave, above with the margins recurved convex, apex with the margins slightly incurved, lanceolate, upper half almost inconspicuously contracted-narrowed, acute apiculate, very minutely patently papillose-finely ciliate, 3-nerved, somewhat fleshy, c. 1.33 by almost 0.4 cm. Lateral sepals porrect, parallel, vertical, apex obliquely slightly incurved, in the basal part concave, above convex, apex, margins incurved, obliquely ovate-oblong, narrowed to the apex, apex dorsally keeled, conical-apiculate, margins minutely papillose; nerves 5 and 2 smaller, somewhat fleshy, c. 1.47 by 0.7 cm above the base. Petals porrect, subhorizontal, apex slightly recurved, convex, narrowly obliquely lanceolate, acute, except base, margins above even inside papillose, 1-nerved, 0.7 by 0.16 cm. Lip with a thin membrane inserted, mobile, somewhat sigmoid, fleshy, 3-lobed, almost calceiforme, in outline narrowly oblong; underneath convex, 0.68 by 0.23 cm, claw fairly conspicuous, quadrangular, to the apex somewhat dilated; base subtruncate with small tooth minute, backwards pointing on either side, above convex-cushion-like-thickened with 2 small, low longitudinal, close, at the base divergent keels; underneath longitudinally grooved, with a thickening not reaching the base of the lip, lateral lobes fairly conspicuous, erect, reversed, obliquely triangular, subobtuse, posterior margins especially at the base slightly recurved, front margin in mid-lobe decurrent, at 1/3 near the apex of the lip merging and forming a broadly triangular cavity, somewhat fleshy, mid-lobe porrect, fleshy, subconical, slightly dorsally compressed, in cross-section elliptic, apex more compressed, slightly contracted, hooked-incurved, acute, above near apex with 2 inconspicuous longitudinal grooves; underneath especially to the apex papillose. Column rather slender, straight, in cross-section triangular, 0.46 cm long; clinandrium deeply concave, subtriangular, posterior margins notched-bilobule, lobules truncate, subcrenulate; stelidia long, porrect, as long as the anther, linear, acute, posterior margins at the base with a small tooth. Anther large, cucullate, porrect, in outline cordate. base bilobulate, thecae membranous; connective gibbose-thickened laterally compressed back obtuse ending, apex in appendage conspicuously porrect, triangular subacute, above obtusely angled convex underneath slightly concave papillose extended, 0.23 cm long. Pollinia 4, laterally compressed, suborbicular-obovate, the 2 outer ones outside convex, 0.06 cm long, the 2 inner ones smaller and much thinner textured; column-foot with the ovary and column making almost straight angles, fleshy, oblong, slightly concave, apex for a very short part free, slightly incurved truncate and slightly dilated, 0.25 cm long. Ovary 6-grooved, finely punctate, 0.4 long; pedicel thin, c. 2.2 by 0.36 cm above the base articulate. (After Smith, 1929)
Colours: Pseudobulbs and leaf dark green, the latter shining above, dull beneath, leathery, sepals egg-yellow, the dorsal one dotted violet inside tip, the lateral ones with a yellowish white border and tip, petals yellowish white, lip light yellow, column light yellow lilac at base, ovary and pedicel greenish white or light green.
Habitat: Epiphyte in low mossy Vaccinium forest; 1420 m.
Flowering time in the wild: October.
Distribution: Malesia (New Guinea).
Distribution in New Guinea: Papua (Indonesia); see map 96-266M.jpg.
Cultivation: Intermediate growing epiphyte.