Bulbophyllum trutiniferum J.J.Verm., Schuit. & de Vogel, Males. Orchid J. 21 (2018) 55
Type: NGF 18165 (van Royen) (holo L)
Epiphytes. Rhizome 0.4–0.6 cm diam.; rhizome scale leaves not long persistent, with few fibers remaining. Pseudobulbs 0.6–1.2 cm apart, distinct, erect, ovoid, 1.9–3.3 by 0.9–1.6 cm, rounded in section, with age wrinkling with numerous longitudinal grooves. Leaf petiole 1.5–2.8 cm long; blade elliptic(-oblong) to obovate-oblong, 8.3–14.0 by 2.2–3.0 cm, index 2.7–5.6; apex acute to acuminate. Inflorescences 4–6 cm long, solitary to many in a fascicle, 1-flowered; peduncle 1.0–2.3 cm long; scale leaves c. 3, the longest 0.58–0.8 cm long; floral bracts 0.6–0.9 cm long. Pedicel and ovary 1.1–2.8 cm long; basal node 0.2–0.3 cm above the floral bract attachment. Median sepal adherent to the laterals along slightly more than c. 1/3 of its length, porrect, elliptic to ovate, 1.35–1.5 by 0.35–0.55 cm, index 2.7–3.9, thick, thicker towards the apex; margins entire; glabrous; apex (sub-)acute; 3-nerved. Lateral sepals as the median sepal but slightly oblique, adnate along their lower margins along c. 1/3 of their length, ovate(-oblong), 1.36–1.55 by 0.4–0.7 cm, index 2.2–3.4. Petals near their base adnate to the column, along their upper margin, porrect, obovate, 0.4–0.5 by c. 0.1 cm, index 4–5, rather thin; margins entire; apex acute-acuminate; glabrous; 1-nerved. Lip about halfway recurved, 3-lobed, in outline ovate(-oblong); lateral lobes attached to the widest part of the median lobe, projecting, retrorse, narrowly ovate, rounded, thin, with glabrous to slightly and minutely papillose margins; median lobe 0.23–0.34 by 0.13–0.19 cm, index 1.7–1.8 (without spreading) , thick ,with entire margins, glabrous; above near the base widely convex, with 2 flat, wide calli which start just above the ligament and continue along the length of the lip, diverging a little and leaving space for a third flat callus, up to the base of the lateral lobes, with a second pair of low, rather narrow, rounded ridges which start near the base and near their front margin of the lateral lobes, and then converging somewhat and leaving a shallowly concave space in between, up to near the apex of the lip where they merge with the moderately convex apical part of the lip,with upper surface glabrous; below with a median ridge along most of the length of the lip, with a narrow, slight median groove; underside glabrous or somewhat shortly hirsute towards the apex, with acute apex. Column including stelidia c. 0.3 cm long; column foot somewhat widened, with rounded lateral wings; stigma obovate; stelidia downwards falcate, triangular, 0.1–0.12 cm long, with obtuse to acute apex; upper margin at the base with or without a slight, deltoid, rounded tooth; anther on underside with a rounded ridge, front drawn-out into a long, rather thick, concave, triangular, obtuse beak, its surface minutely papillose; pollinia 4, the inner pair somewhat shorter than the outer pair.
(after Vermeulen, Schuiteman & de Vogel 2018)