Bulbophyllum deergongense J.L.Miao & J.W.Zhai, 2023

Miao, Jiang-Lin, Zhang, Hua-Yuan, Zhu, Wen-Tao, Liu, Zhen, Ji, Hong-Yu, Liu, Zhong-Jian & Zhai, Jun-Wen, 2023, Bulbophyllum deergongense (Dendrobiinae; Malaxideae; Epidendroideae; Orchidaceae), a new species from Tibet, China, Phytotaxa 619 (2), pp. 197-202 : 200-201

Bulbophyllum deergongense J.L.Miao & J.W.Zhai , sp. nov. DZṪÑƂü± ( Fig. 2 )

Type:— CHINA. Tibet: Motuo, Deergong (DZṪÑ), 29°16′N, 95°12′E, on the tree trunks in mountain forest, Zhai 0180 (holotype: FAFU; isotype: IBSC)

This new species similar to B. reptans , but it differs in its yellowish green flower without markings, oblong-ovoid petal with a purple-brown round spot at the apex and elongate cylindrical pseudobulbs with prominent ridge, distantly placed on the rhizome, 15.0–20.0 cm apart.

Perennial epiphytic herbs on trunks. Rhizome terete, slender, nodes 2.0–3.0 mm long, smooth, internodes covered with membranous semi-circular sheaths, 4.0–6.0 mm long. Roots emerging from the nodes, up to 6.0 cm long. Pseudobulbs distantly placed on the rhizome, 15.0–20.0 cm apart, long cylindrical to elongate conical, slightly quadrangular in circumference, sometimes twisted, 2.5–4.0 × 0.8–1.2 cm, yellowish green, ridged, remnants of sheaths persist in form of fibres towards the base. Leaf solitary, terminal, linear to elongate-elliptic, 9.0–12.0 × 1.5– 2.0 cm, acuminate, apices asymmetrically divided, base cuneate, stiff, leathery, petiolate, petiole 0.9–1.1 cm long. Inflorescences arise from the base of the annual pseudobulbs, racemose, slender, 18.0–23.0 cm long, bearing 12–15 lax, semi-secund flowers. Flowers not fully open, 1.0– 1.6 cm long, yellowish green, dorsal sepal oblong-lanceolate, 7.0–9.0 × 2.0–3.0 mm basally, long acuminate, abaxially angled, margin entire; lateral sepals obliquely lanceolate, slightly curved, 2.9–3.1 × 0.9–1.1 mm, base slightly connate to form a small sac, margin entire; petals oblong-obovate to spatulate, 2.0–4.0 × 0.9–1.1 mm, tapering towards base, light green, with a purple-brown round, apical spot, margins entire, tongue-shaped, recurved downwards, 2.9–3.1 mm long, apex obtuse to round, green, longitudinally grooved, reddish brown marginally, green in the middle on both sides, similar colour pattern underneath; gynostemium 0.9–1.1 mm long, with 2 distinct ciliate stelidia on each sides, 0.9–1.1 mm long, stelidia pointing forward, slightly arched, with one almost rounded tooth on both sides on the lower margin, foot 1.9–2.1 mm long, with a callus on the middle, pollinia 2.

Phenology:— Flowering February–March.

Distribution and Habitat:— Currently known only from Motuo, south-eastern Tibet Autonomous Region, China, on tree trunks at 1800–2200 m.

Etymology: —The specific epithet is derived from the name of Deergong (DZṪÑ), which is the type locality of this species.

Figures

FIGURE 2. Bulbophyllum deergongense J.L.Miao & J.W.Zhai, sp. nov. A–D. Flowering plant. E. Longitudinal section of flower. F. Pollinium. G. Sepals. H. Labellum. I. Petal. J. Column. K. Dorsal sepal. L. Column and ovary (side view). M. Labellum (ventral view).