Bulbophyllum section Lepanthanthe Schltr., Repert. Spec. Nov. Regni Veg. Beih. 1 (1912) 704
Small to medium sized epiphytes. Rhizomes creeping or limply pendulous; rhizome bracts thin to thick, minutely colliculate to (densely) papillose, rather persistent, finally caducous including the veins. Roots sprouting mainly below the pseudobulbs, spreading, and densely and coarsely papillose-rugulose-verrucate in species with rhizome creeping; mainly near to the base of the rhizomes, growing backwards towards the substratum over or alongside the rhizome, and finely papillose in species with rhizome pendulous. Pseudobulbs minute compared to the size of the plant, 1-leafed, with shoots sprouting at its basal node and fused to the pseudobulb for up to half the length of the latter. Leaves persistent, thick, veins inconspicuous. Inflorescences sprouting from or above the (sub-)basal node of the pseudobulb, single to many-fasciculate, racemose with flowers spirally arranged (approx. tristichous in Bulbophyllum antennatum). Peduncle short and not protruding from the subtending rhizome bract, to long and with the top well above the leaves, peduncle bracts 2— 6, scattered but most in the basal half of the peduncle. Rachis, if present, not thickened (peduncle and rachis verrucate in some species). Flowers per inflorescence 1— several open at a time; floral bracts not amplexicaul; pedicel with the basal node well above the attachment of the floral bract, approx. as long as the ovary or distinctly longer. Sepals free, the laterals sometimes connate along their lower margin, somewhat longer to distinctly shorter than the median; 1.8— 10 mm long, (ob-)ovate to (transversely) elliptic, top a fleshy, subulate projection often distally thickened and rounded (projection inconspicuous in Bulbophyllum lagaroglossum; lateral sepals apiculate in Bulbophyllum nephropetalum); margins glabrous to ciliate, (rather) thin, 3-veined (lateral sepals 5-veined in Bulbophyllum trachypus), surface glabrous. Petals 1— 3.2 mm long, orbicular or (transversely) elliptic to (ob-)ovate (narrowly triangular-linear in Bulbophyllum antennatum), retuse to acute-acuminate, margins entire to (distally) erose, sometimes unguiculate (below a cordate base), glabrous to ciliate; thin, 1-veined, surface glabrous (adaxially hirsute distally in Bulbophyllum antennatum). Lip mobile on a thin ligament, without auricles near the ligament, undivided or 3-lobed with 'lateral' lobes close to the base (see note below), 1— 2.5 mm long (4— 5.5 mm long in Bulbophyllum antennatum), (ob-)ovate to elliptic or oblong (spathulate in Bulbophyllum antennatum; subhastate in Bulbophyllum nephropetalum), margins glabrous, papillose (with elongated papillae), ciliate or densely vesiculose; adaxially without ridges, or with a median ridge and/or with two (distinctly converging) flexural ridges (sometimes projecting as 'lateral' lobes over the adaxial surface, see below), surface glabrous to papillose; abaxial surface glabrous, papillose, with 2 sub-lateral patches of elongated papillae, or vesiculose towards the margins. Column with rostellum front approx. level with the stelidia tips or receding in between these, stigma large, without keels inside, proximally usually more or less protruding or with a tooth, column foot tapering towards its top, sometimes with (inconspicuous) lateral lobes next to the ligament, free part rather short, often with a median tooth just short of the ligament. Stelidia 1/2 of the length of the column or shorter, wing-shaped, deltoid or (narrowly) triangular, often erose along the upper margin, often with a distinct, antrorse (patent in Bulbophyllum nephropetalum) tooth along the lower. Anther abaxially with a low, rounded crest, front not concave, front margin drawn out into a small, triangular beak or not. Pollinia 2, without appendages.
New Guinea: 16 taxa. Altogether 16 accepted taxa (22 names): New Guinea, West Pacific.
Revised in Vermeulen (1993: 73) with additions and amendations in Vermeulen (2008). Includes six species with a limply pendulous rhizome and fasciculate as well as racemose, short inflorescences; the others have creeping rhizomes, and single, long inflorescences. The range of variation in flower morphology is similar in both groups. The lateral lobes on the lip consist of true marginal projections and projecting flexural folds together. If the first are most prominent the lateral lobes appear inserted along the margins (e.g. Bulbophyllum cruttwellii, Bulbophyllum trachypus); if both are equally prominent, or if the flexural folds are most prominent, the attachment of the lateral lobes appears to converge over the adaxial surface of the lip, their proximal edges often clasping the median ridge (e.g. Bulbophyllum lepanthiflorum, Bulbophyllum bulliferum).
The following taxa in this program belong to this Section: