Bulbophyllum leptobulbon J.J.Verm., Blumea 41 (1996) 358, fig. 11
Type: Jongejan cult. 774 (holo L, spirit 7744)
Rhizome creeping, 2.5-3.0 mm diam. Pseudobulbs 1-leafed, cylindrical or narrowly obovoid, 2.5-3.3 cm apart, 5.5-6.8 by 0.4-0.5 cm, somewhat flattened. Petiole 1-2 mm. Leaf blade elliptic to (ob)ovate, 8.0-11.0 by 1.6-2.1 cm, index (length/ width) 3.8-6.6, obtuse. Inflorescence 9-12 cm, 1-flowered. Peduncle 4.0-4.5 cm; bracts 3, the longest c. 6 mm, acute. Floral bract tubular, c. 7 mm, cuspidate. Pedicel and ovary 62-70 mm, with the node 6-7 mm from the floral bract. Flowers wide open. Median sepal spreading, flat, ovate, c. 30 by 6 mm, index (length/width) c. 5, acute, base rather narrowly attached; rather thin; glabrous; with 3 veins the median of which is somewhat prominent abaxially. Lateral sepals free, hardly falcate, hardly oblique, triangular, c. 34.0 by 5.5 mm, index (length/width) 6.1-6.2; base rather broadly attached; otherwise as the median sepal. Petals erect, not falcate, somewhat oblique, obovate, 5.0 by 3.2 mm, index (length/width) 1.5-1.6, tip acuminate, margins entire, finely ciliate; base narrowly attached; thin; with 1 vein; surface glabrous. Lip curved about half-way, general outline obovate, c. 5.5 by 3.0 mm, index (length/ width) 1.8-1.9 (not spread), tip obtuse, margins entire, ciliate; thick and solid; adaxially with a concave basal part, with an about flat top part, with 2 rather narrow, obtuse ridges diverging and coinciding with the margins near the base, and continuing up to c. 1 /2 of the length of the lip, between these ridges two other, widely rounded, longitudinal swellings, adaxial surface glabrous except for 2 patches with very fine transverse riblets in the basal half of the lip, close to the margins; abaxially with a rather distinct, retuse median ridge in the basal half, surface glabrous. Column from ovary to the tip of the stelidia c. 2.4 mm long; column foot widened and with small, semi-circular lateral wings at its tip. Stelidia short, not falcate, triangular, c. 0.5 mm, acute, with a small, deltoid, subacute tooth along the upper margin; stigma with a callus at its base flanked by two distinct, deltoid, obtuse wings on the lower margins of the column, elliptic. Anther abaxially with the top part papillose, widely overtopping the front margin, and with a distinct, widely rounded ridge over most of its length; front margin not protruding, not concave, rounded. Pollinia 4, ellipsoid or obovoid, flattened on both sides, the inner almost as long as the outer. Stipes absent. (After Vermeulen, 1995)
Colours: Not recorded.
Habitat: Epiphyte in montane forest; 2200 m.
Distribution: Malesia (New Guinea).
Distribution in New Guinea: Papua New Guinea; see map 96-2026M.jpg.
Cultivation: Cool growing epiphyte.