Bulbophyllum section Epicrianthes (Blume) Hook.f. Fl. Brit. Ind. 5 (1890) 753
Small to large epiphytes. Rhizomes patent to pendulous; rhizome bracts thin, glabrous to minutely colliculate, caducous with the veins hardly more persistent. Roots sprouting mainly near to the base of the rhizomes, growing backwards towards the substratum over or alongside the rhizome, glabrous or slightly and minutely hirsute locally. Pseudobulbs conspicuous compared to the size of the plant, 1-leafed, with shoots sprouting at its basal node and fused to the pseudobulb over less than half of the length of the latter, or shoots sprouting the same distance above its basal node, perforating the pseudobulb over the distance between its basal node and the spot of emergence. Leaves persistent, thick, veins inconspicuous. Inflorescences sprouting at the basal node of the pseudobulb only, sometimes also two nodes lower down on the same shoot; densely fasciculate, 1-flowered. Peduncle shorter than the pseudobulbs, peduncle bracts 1— 3, near the base of the peduncle. Flowers per sympodium 1 open at a time; floral bracts tubular; pedicel with the basal node well above the attachment of the floral bract, approx. as long as the ovary. Sepals free, the laterals approx. as long as the median; 5— 18.5 mm long, elliptic to ovate, acute to shortly acuminate; glabrous, (rather) thick, 3— 9-veined. Petals 0.3— 5.5 mm long excluding appendages, usually a narrow seam alongside the column base, also elliptic to ovate, distal margin with 3— 24 appendages, margins otherwise entire, glabrous; thin to rather thick, 3— 5-veined; surface glabrous; appendages differing in texture from the petal itself, stiff to mobile at the slightest air movement, usually thickened and/or widened distally (thread-like, not thickened in Bulbophyllum johannuli), surface colliculate to papillose (hirsute in Bulbophyllum phymatum). Lip mobile on a thin ligament, with or without slight auricles near the ligament, undivided, 1.3— 7 mm long, elliptic to (ob-)ovate or oblong, margins entire, glabrous, projecting near the base of the lip, then converging over the adaxial side of the lip, usually until they almost meet, at that level usually clasping two more ridges running parallel to the median ridge, beyond that level either continuing parallel over the adaxial surface, or spreading again, adaxial surface glabrous, or distally increasingly rugose, verrucose or papillose; abaxial surface usually with a patch of conspicuous papillae or vesicles close to the margins, otherwise glabrous to papillose to hirsute. Column with rostellum front (somewhat) receding in between the stelidia, stigma slit-like to wide and rounded, without keels inside, proximally not protruding, column foot not widened towards its top, free part short; with or without small, antrorse lobes next to the ligament. Stelidia shorter than 1/2 of the length of the column; short but not vestigial, approx. deltoid to triangular, with or without a small tooth, or denticulate along the upper margin, usually with a minute, obliquely antrorse tooth along the lower margin, close to the tip, and/or a deltoid, rounded to acute wing lower down. Anther abaxially with a (low) rounded crest, front somewhat concave or not, front margin usually drawn out, emarginate. Pollinia 2, or 4, with the inner more or less than half as long as the outer, sometimes with a thick appendage
New Guinea: 18 taxa. Altogether 39 provisionally accepted taxa (44 names): China, Myanmar to Java, East to New Caledonia.
From the lip base onwards, the lip margins converge over the adaxial side of the lip, so that the true adaxial surface is in many species no more than a narrow strip over what is actually the adaxial side of the lip. The patches of vesicles along the margins of the adaxial side of the lip are actually part of the abaxial surface. In all species descriptions so far published, the adaxial side of the lip is taken for its true adaxial surface. The patches of vesicles are described as pertaining to the lip margin, while they are not – although they are growing from the lip circumference. In some species this structure is obscure, and in others (e.g. Bulbophyllum epicrianthes) the actual lip margins spread out again after converging, and largely coincide with the lip circumference. The latter state is shared with section Schistopetalum.
Most species of section Epicrianthes are relatively rare, with little material available of each. The differences between the species are often minor, but at present application of a narrow species concept describes the morphological patterns most accurately (Vermeulen & O'Byrne, 2008).
Three series can be distinguished:
a Petals with 3 appendages
b Petals with 4 or more appendages, all of similar shape and texture
c Petals with 4 or more appendages; of two different shapes.
The following taxa in this program belong to this Section: