Bulbophyllum subium J.J.Verm., Schuit. & de Vogel

Vermeulen, Jaap J., Schuiteman, André & De Vogel, Edward F., 2020, Sixteen new species of Bulbophyllum section Polymeres (Orchidaceae) from New Guinea, Lankesteriana 20 (3), pp. 301-330 : 315

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

( Fig. 9 )

TYPE: Indonesia, Papua Province, Mimika Regency, PT-Freeport Indonesia Concession Area, below Hanekam Tunnel , 2500 m alt., 15 Oct. 1998, Johns 9057 (holotype K!, isotypes BO, L!, MAN, FREE ).

DIAGNOSIS. Shares the clustered growth, combined with narrow sepals and short, upwards falcate stelidia with Bulbophyllum galliaheneum Van Royen , from which it differs by the elliptic to ovate, acute (versus obovateoblong, subtruncate to rounded) petals, by the much denser and larger hirsute patches proximally on the adaxial side of the lip, and by the triangular (versus narrowly triangular and distally subulate) stelidia; and with B. odontopetalum Schltr. , from which it differs by the elliptic to ovate, minutely erose and/or ciliolate (versus obovate-spathulate, coarsely fimbriate) petals, and by the hirsute (versus glandular-papillose) lip margins.

Small epiphyte with creeping rhizomes and spreading roots. Rhizome ca. 2.5 mm diam., sections between pseudobulbs 0.3–0.5 cm long, arising from the basal node of the pseudobulb; rhizome scales thin, little persistent. Pseudobulbs distinct, ellipsoid, 1.0– 1.2 × 0.3–0.4 cm, hardly angular but concave on the side where the new shoot arises. Leaf: petiole 0.5–1.5 mm long; blade elliptic to obovate, 2.9–6.0 × 0.5–0.7 cm, ratio length/width 4.1–12; subacute. Inflorescences single or several together, ca. 8 cm long, 1-flowered. Peduncle ca. 4.5 cm long, scales ca. 4. Floral bracts ca. 4.0 mm long. Flowers: pedicel plus ovary ca. 9 mm long, basal node ca. 2 mm above the floral bract attachment. Median sepal free, recurved, ovate, ca. 22 × 3.2 mm, ratio length/width 6.8–6.9; long-acuminate, margins entire, ciliolate, surface glabrous; 3-veined. Lateral sepals as the median but ovate-triangular, ca. 28.5 × 3.0 mm, ratio length/width ca. 9.5. Petals porrect, elliptic to ovate, 3.1–4.5 × 1.0– 1.1 mm, ratio length/width 2.8–4.5; acute, margins minutely erose and/or ciliolate, surface glabrous; 1-veined. Lip slightly recurved near base, elliptic to oblong, 4.6–5.0 × 1.3–1.8 mm, ratio length/width 2.5–3.9 (without spreading); rounded, margins entire, approx. densely hirsute proximally, glabrous distally; thick; adaxially concave close to the base, this cavity with a proximally widening, glabrous median crest which continues up to 1/3–2/5 of the length of the lip, the cavity bordered by two short, converging ridges with a densely papillose crest, adaxial surface otherwise slightly concave and with two densely hirsute patches towards the margins in the proximal 1/3–2/5 of its length, slightly convex and slightly papillose elsewhere; abaxially convex and shortly hirsute with scattered glandular papillae near the base, slightly concave and glabrous elsewhere. Column including stelidia 0.9–1.2 mm long, stigma elliptic, proximally distinctly protruding from the column face, foot deeply furrowed, distally distinctly widened, with spreading, obtuse lateral teeth. Stelidia upwards falcate, triangular, 0.3–0.4 mm long, acute. Pollinia 4.

COLOURS: flowers dark red-purple.

ETYMOLOGY: subium (Latin) = moustache, referring to shape of the hairy patches on the lip (the word is used as a noun in apposition.

HABITAT AND ECOLOGY: epiphyte in Casuarina forest. Elevation 2500 m.

Figures

FIGURE 9. Bulbophyllum subium J.J.Verm., Schuit. & de Vogel. a. Habit. b. Flower. c. Flower analysis, from left to right: median sepal, petal, lateral sepal, lip. d. Petal. e. Lip, left: adaxial side, right: abaxial side. f. Column and lip, lateral view.g. Column, left: frontal view; right: lateral view.h.Anther, left:adaxial side, right: abaxial side.i. Pollinia, above: one pair, below: two pairs. Drawn from Johns 9057 by © J.J. Vermeulen, from herbarium material.