Bulbophyllum leysianum Burb.

 Bulbophyllum leysianum Burb.; J. Hort. Soc. London 17: 134, t. 19 1894.

Bulbophyllum leysianum Burb.; Photos Le MDung

Vietnamese name: 

Chinise name: 

Common Name: 

The Leysia Bulbophyllum

Latin Name: 

Bulbophyllum leysianum Burb.

Family: 

Orchidaceae

Synonym Name: 

TYPE: 

Malaysia. Sabah: Sinaroup Village, Burbidge s.n

Description: 

Long-creeping epiphyte. Rhizome ca. 3 mm in diameter, sections between pseudobulbs 0.6–1.5 cm long. Pseudobulbs 1–leafed, glossy green, obliquely ovoid, 1.1–2.0 cm long, 0.5–1.3 cm wide. Leaves green, thick, narrowly elliptic, 6–9 cm long, 2.2–3.0 cm wide, apex obtuse; petiole ca. 2 cm long. Inflorescence from mature pseudobulbs, 1-flowered, ca. 18 cm long, peduncle ca. 7.4 cm long, bracts 4, 3–8 mm long, apex acute. Flowers slightly to moderately opening, dorsal sepal white, suffused pink, greenish around the midvein and towards the base, lateral sepals white, suffused pink, petals white with green veins and pink appendage, lip white, suffused pink, slightly greenish abaxially, and with patches of pink–red spots; pedicel plus ovary ca. 2.7 cm long, floral bract tubular, ca. 11 mm long. Dorsal sepal concave towards the base, narrowly ovate, ca. 5.5 cm long, 1.6 cm wide, apex rounded and mucronate, margins entire, ciliolate, surface almost glabrous, abaxially keeled along the midvein; ca. 12– veined. Lateral sepals loosely adherent along the lower margins, upper margin curved inwards until it (almost) touches the upper margin of the opposite sepal, flat, obliquely ovate–triangular, clawed, 4.0–4.2 cm long, 7–8 mm wide above the claw, apex acute, margins entire; glabrous, ca. 10-veined. Petals obliquely elliptic, ca.7mmlong,2mmwide,apexwithaca.3mmlong filiform processus endinng with a globular, warty apex; margins entire; glabrous, 3-veined. Labellum fleshy, curvedinlateralview,(elliptic-)oblong,ca.5mmlong, 1.8 mm wide, apex rounded, margins ciliate, adaxially slightly concave towards the base, elsewhere with a shallow median furrow which ends just short of the slightly convex apex, surface almost glabrous towards the base, elsewhere hirsute, shorter so towards the apex, abaxially almost glabrous, abaxially with a distinct keel, surface glabrous. Column ca. 2.8 mm long; stelidia short, triangular, acute, with a small, antrorse, acute toothalongtheuppermargin,anddeltoid,obtusetooth along the lower margin. Anther cap with the frontal margin drawn out into a widely rounded beak.

Distribution: 

Peninsular Malaysia, Borneo, Java. This species has been known only from Malesia and hence its occurrence in Vietnam shows a very disjunct distribution range. In VietNam, It found in Khanh Hoa Province: Hon Ba Nature Reserve.

Ecological: 

Epiphyte on small branches along a stream over granite bedrock, ca. 400 m a.s.l. Very rare in Hon Ba reserve. Flowering in November.

Note: 

This species may be confused with B. antenniferum (Lindl.) Rchb.f., which has been reported from Peninsular Malaysia and peninsular Thailand (Vermeulen et al. 2015). Bulbophyllum leysianum differs by the nearly oblong, adaxially coarsely hirsute labellum of less than 2 mm wide (vs. labellum ovate-triangular, adaxially finely hirsute only in the centre and otherwise glabrous, and more than 2 mm wide in B. antenniferum).

Reference: 

- theplantlist.org

- efloras.org

- orchidspecies.com

- ipni.org

- Truong, Vuong & Truong, Tam & Dang, Son & Nguyen, Ty & Vermeulen, Jaap. (2020). New records of Bulbophyllum in the Flora of Vietnam. Lankesteriana. 10.15517/lank.v20i1.41130.