Scientific name: Bulbophyllum coweniorum J. J. Verm. et P. O’ByrneEnglish name: Vietnamese name: Lọng hoa lớnOther name:
Creeping epiphyte. Rhizome rigid, woody, 4.5–6 mm diam., with erect pseudobulbs distant on 0.9–1.6 cm, remnants of bracts persistent as fine fibres. Roots mainly below the pseudobulbs. Pseudobulbs ovoid to cylindrical, 3.5–5.5 × 1.2–1.6 cm. Leaves petiolate; petiole 3–5.5 cm long; leaf blade elliptic to obovate, 10–16.5 × 2.7–4.2 cm, obtuse. Inflorescence 1–1.2 cm long, erect to patent, with 2–3 bracts, the longest 1.4–1.8 cm long. Floral bracts tubular, 1.5–1.8 cm long, acute. Pedicel and ovary 7–8 cm long, slightly curved at the base and apex. Flowers resupinate, not widely opening. Sepals and petals dull yellowish-green with red spots, free, spreading, rather thick, glabrous, entire, 8–9-veined, tapering and acute at apex. Median sepal erect, narrowly triangular-ovate, 2 × 1.2 cm, at the base suddenly shortly narrowing; lateral triangular-ovate, oblique, 2.3 × 1.2 cm, acute, lower margin with a prominent fold at the middle, broadly attached to column foot. Petals narrowly triangular-ovate, 2 × 0.6 cm, with broad base. Lip movable, white flushed with purple to the base, oblique ovoid in outline, recurved, 10.5 × 7.5 mm; obtuse, thick, entire, almost glabrous, somewhat coarsely warty near apex, in basal half concave, finely ciliate at margin near the base. Column broad, 4 mm tall, stigma concave; column foot prominent, strongly bent forward; stelidia minute, triangular, acute, 3–3.5 mm long. Anther almost hemispheric, glabrous to finely papillose. Pollinia 4, ovoid, unequal, in two pairs
English – Cowen’s Bulbophyllum (named after Mr. and Mrs. Cowen, who cultivated this species and successively made it flowering in their garden in Thailand), proposed Vietnamese name – Long hoa lon.
Ecology and phenology.
Creeping branch and trunk epiphyte. Evergreen broad-leaved submontane forests on silicate rocks. 800–1500 m a.s.l. Flowers in March – April. Flowering in cultivation was observed in January–March, October and December (Vermeulen, O’Byrne, 2003; Schuiteman et al., 2008).
Vietnam: Dak Lak province (Chu Yang Sin Mountains) and Kon Tum province (Ngoc Linh Mountains);
Laos: Champasak province (no exact locality, Schuiteman et al., 2008).
Threat and conservation.
The wide deforestation due to uncontrolled primitive burning and shifting agriculture, as well as forest logging throughout the Lao PDR territory, is the leading factor of the species extinction (Cockel, 2013). Additional threat factor is commercial plant collecting, mainly for export to China as ornamental and medicinal plant used in traditional oriental medicine (Lamxay, 2009). While this species appears rather common in the orchid trade and in cultivation, its distribution and occurrence in Lao PDR remains unclear (Vermeulen, O’Byrne, 2003; Schuiteman et al., 2008; Cockel, 2013). Beside the type, two additional available reports in Laos are based on cultivated specimens originated from Champasak province without indication of exact locality and data on ecology (Schuiteman et al., 2008). Present record of this species in Vietnam is based on the single observed, highly depleted population standing on the verge of full extinction due to overexploitation and habitat loss. The absence of any current field data makes IUCN Red List criteria not well applicable for identification of species’ status. Data deficient (DD) status should be formally applied for this species in formal terms, whereas in fact it may be very near to full extinction in the nature (nationally CR).
This and similar related species are used in traditional medicine for treating hemoptysis, pneumonia, sore throat and chronic gastritis according to verbal information obtained from people of local minorities. Scientific data on medicinal activity of any substances obtained from these plants are not yet available.