Bulbophyllum nannae J.J.Verm., Schuit. & de Vogel, sp. nov.

(Fig. 5, 18B)

TYPE: Papua New Guinea, Milne Bay Province, Bonenau, 1300—1400 m alt., Jongejan cult. 1408 (holotype L!, spirit material).

DIAGNOSIS. Most similar to Bulbophyllum neoguineense J.J. Sm., differs by the wider petals (ratio length/width 1.7—1.9, versus ca. 3.6) and by the base of the stigma which does not protrude from the face of the column.

Rather small epiphyte with creeping rhizomes and spreading roots. Rhizome 2.0– 2.5 mm diam., sections between pseudobulbs 0.8–1.7 cm long, arising from the basal node of the pseudobulb; rhizome scales thin, little persistent. Pseudobulbs distinct, ellipsoid to ovoid, 1.1– 2.0 × 0.4–0.5 cm, hardly angular. Leaf: petiole 0.4–0.6 mm long; blade elliptic to ovate, 3.6–4.5 × 0.8–1.2 cm, ratio length/width 3.7–4.5; acute. Inflorescences single or a few together, ca. 8 cm long, 1-flowered. Peduncle ca. 5 cm long, scales ca. 4. Floral bracts ca. 4 mm long. Flowers: pedicel plus ovary ca. 20 mm long, basal node ca. 1 mm above the floral bract attachment. Median sepal free, recurved, ovate, 8.0–9.5 × 2.8–3.0 mm, ratio length/width 2.6–3.4; acute, margins entire, minutely papillose, surface glabrous; 5-veined. Lateral sepals as the median but spreading, ovate-triangular, 8.0–11.0 × 3.2–3.4 mm, ratio length/width 2.5–3.3, margins glabrous. Petals porrect, rhombiform, 3.7–4.0 × 2.1– 2.2 mm, ratio length/width 1.7–1.9; obtuse, margins approx. entire, finely papillose, surface finely papillose distally; 1-veined. Lip slightly recurved, ovate, 6.4– 6.7 × ca. 2.0 mm, ratio length/width 3.2–3.4 (without spreading); rounded, margins entire, minutely papillose proximally, glabrous distally; thick and soft; adaxially concave in the proximal 1/3–1/2, this cavity bordered by two slightly converging ridges distally gradually merging into the convex distal part of the lip, adaxial surface glabrous; abaxially with a median furrow which is deepest in the proximal, otherwise convex half, distal half somewhat concave, abaxial surface minutely papillose proximally. Column including stelidia 2.6– 3.0 mm long, stigma narrowly obovate, proximally not protruding from the column face, foot distally widened, with spreading, rounded lateral teeth. Stelidia somewhat sigmoid, narrowly triangular, distally subulate, ca. 1.7 mm long, acute. Pollinia 4, the inner more than half as long as the outer.

COLOURS: sepals yellow-green, pale yellow along the margins, veins dark red. Petals white, yellow-green in centre, with large dark red blotches. Lip yellow, suffused brown at apex and abaxially near the base. distally and urple, white towards the edges. Petals white. Lip purple, apex green, papillae pale purple, the larger white. Column yellow.

ETYMOLOGY: named after Nanna Høeg, youngest daughter of the first author, at the occasion of her 20st birthday.

HABITAT AND ECOLOGY: epiphyte low on tree trunk. Elevation 1300–1400 m.