Habenaria balfouriana Schltr., Repert. Spec. Nov. Regni Veg. 20: 381 (1924).

Pandey, Tirtha Raj & Jin, Xiao-Hua, 2021, Taxonomic revision of Habenaria josephi group (sect. Diphyllae s. l.) in the Pan-Himalaya, PhytoKeys 175, pp. 109-136 : 109

6. Habenaria balfouriana Schltr., Repert. Spec. Nov. Regni Veg. 20: 381 (1924).

Type.

China, Yunnan, 1910, G. Forrest 6149 [lectotype designated here: E (E00381989 image!); isolectotypes: PE (00340644!), IBSC (0636129!), K (K000796932 image!), P (P00370551 image!)] .

Description.

Terrestrial herbs, 10-24 cm tall. Tubers oblong. Stems densely pubescent. Leaves 2, opposite, basal; leaf blade ovate or ovate-orbicular, 2-4.5 cm long, 2-4 cm broad, fleshy, apex acuminate or acute. Inflorescence 8-20 cm long, subdensely 3-12-flowered; rachis 5-10 cm long; floral bracts lanceolate, apex acuminate. Flowers yellowish-green; ovary and pedicel arcuate, fusiform, 0.8-1 cm long, finely papillate-hairy. Dorsal sepal forming a hood with petals, erect, ovate, concave, 5-6 mm long, 3.5-4 mm broad, margin ciliate-denticulate, apex obtuse; lateral sepals oblique, ovate-oblong, reflexed, 6-7 mm long, 3.5-4 mm broad, apex subacute. Petals 2-lobed, glabrous; upper lobe obliquely ovate-lanceolate, 5-6 mm long, 2-2.2 mm broad; lower lobe a tooth at base of upper lobe, ca. 0.5 mm long; lip deeply 3-lobed above base, spurred; lateral lobes linear, retrorse, almost embracing ovary, linear, 1-1.2 cm long, apex bent; mid-lobe linear, reflexed, ca. 1 cm long; spur pendulous, slightly curved, clavate, 1.2-2 cm long. Column stout, anthers parallel, connective wide; stigmatic processes sub-oblong. (Fig. 14 ).

Phenology.

Flowering in July and August.

Habitat.

Montane forests, shrubby grasslands, alpine meadows; 3000-4300 m elev.

Distribution.

Endemic to the Pan-Himalaya, found only in Hengduan Mountains; S Hengduan. (Fig. 15 ).

More illustrations.

Wu et al. (2010, fig. 194, 3-4).

Additional specimens examined.

S HENGDUAN: Daocheng, 4236 m elev., 2007, X.H. Jin 9194 (PE); Yanyuan, 3600 m elev., 1983, Qinghai-Tibet Team 12529 (PE); Yulong (Lijiang), 3000 m elev., 1937, T.T. Yu 15316 (PE); Yulong (Lijiang), mountain meadows, 3344 m elev., 1906, G. Forrest 2739 (K).

Note.

This species grows above 3000 to 4300 m in grassy alpine meadows. Habenaria balfouriana has a restricted distribution in the southern Hengduan Mountains, sharing the habitat with the similar-looking H. aitchisonii . Though H. aitchisonii and H. balfouriana were found closely allied in a recent molecular study ( Jin et al. 2017), they are distinct morphologically; both have yellowish-green flowers with bilobed petals, but the former has an elongated spur that exceeds the length of the ovary and pedicel (versus spur shorter than ovary in H. aitchisonii ).

Figures

Figure 14. Habenaria balfouriana A habit B floral bract C pedicellate ovary with spur D petal E dorsal sepal F lateral sepal G lip (A photographed from the isolectotype specimen G. Forrest 6149, PE B-G drawn from the same specimen by T. R. Pandey).

Figure 15. Distribution of Habenaria balfouriana (black circles) in the Pan-Himalaya.