Dendrobium hekouense

Dendrobium hekouense Z. J. Liu & L. J. Chen, Ann. Bot. Fennici. 48: 87. 2011

Dendrobium hekouense Z. J. Liu & L. J. Chen; Photos Nguyen Hoan Tuan

Vietnamese name: Hoàng thảo hà khẩu

Chinese Name: Hekou (河口)

Common Name: The Hekou Dendrobium (A town of northern Yunnan Province China)

Latin Name: Dendrobium hekouense Z. J. Liu & L. J. Chen

Family: Orchidaceae

Synonym Name: No synonyms are recorded for this name

Description:

A small plant. Pseudobulbs aggregate, sub- ellipsoid, 6–12 mm long, 4–6 mm wide, base contracted and shortly stalked, with 2–3 nodes, internodes 2–6 mm long. Leaves coriaceous, narrowly elliptic to oblong-elliptic, 1.1–1.8 cm long, 3.5–6 mm wide, apex acute, base shortly petioled and sheathing. Inflorescence arising from leafless pseudobulb, lateral, 1-flowered; peduncle 4–4.5 mm long, with 1 membranous cup-shaped sheath at base; bracts membranous, ovate, 2–2.5 mm long; pedicel and ovary 6–7 mm long. Flowers spreading horizontally. Sepals and petals white, with a purple midvein, abaxially grey-green; lip white, densely maroon- spotted on disc and lateral lobes and with purple- red spots on mid-lobe; dorsal sepals broadly ovate, 7–7.5 mm long, 5.5–6 mm wide, apex acute; lateral sepals obliquely ovate-triangular, 11–12 mm long, 13–15 mm wide, apex acute; mentum cylindrical, 1.2–1.3 cm long, 6–8 mm wide, rounded-bilobed at tip; petals obovate- elliptic, 7.5–8 mm long, 4–4.5 mm wide, apex acute; lip pubescent adaxially, 3-lobed; lateral lobes long-subtriangular, 1.3–1.4 cm long, 5–5.5 mm wide; midlobe reniform, 3.5–4 mm long, 7–7.5 mm wide, apex shallowly 2-lobed, mar- gins irregularly denticulate; column thick and short, ca.1 mm long; column-foot 1.3–1.4 cm long; operculum conical, grey-green, front part spotted with purplish toward base. Flowering in August–September.

Flowering: Flowers bloom in the spring and summer.

Distribution: Found in Yunnan China. In Vietnam: Ha Giang.

Ecological: Growing on the underside of branches so the flowers do not get water in them at elevations of 1000 to 2000 m, cool growing epiphyte that blooms in the fall.

Type: China. Yunnan, Hekou, growing on tree trunk, alt. 1000 m, 23.VIII.2008 Z. J. Liu 4093 (holotype NOCC).

Note: Dendrobium hekouense is similar to Dendrobium wangliangii (cf. Hu et al. 2008) from which it differs by its dorsal sepal larger than petals, obliquely ovate-triangular lateral sepals broader than long, cylindrical mentum 1.2–1.3 cm long, and a trilobed lip.

 Reference:

- theplantlist.org

- efloras.org

- orchidspecies.com

- ipni.org

- Zhong-Jian Liu & Li-Jun Chen, Dendrobium hekouense (Orchidaceae), a new species from Yunnan, China; Ann. Bot. Fennici 48: 87–90