Calanthe × yarlungzangboensis P. P. Wu & Z. Wang, 1852

Wu, Po-Po, Wang, Zi, Jia, Ning-Xia, Guo, Shi-Wei, Liu, Chang-Cheng, Jin, Xiao-Hua & Guo, Ke, 2021, Calanthe × yarlungzangboensis, a new natural hybrid in genus Calanthe (Orchidaceae) from China, Phytotaxa 518 (2), pp. 167-174 : 171-172

Calanthe × yarlungzangboensis P. P. Wu & Z. Wang , hybr. nov.

[ Calanthe griffithii Paxton & Lindley × Calanthe tricarinata Lindley ] ( Fig. 4 & 5 )

Diagnosis: This natural hybrid is similar to C. griffithii and C. tricarinata by sharing the similar shape, size of sepals and petals, but it differs from the latter two by having lateral lobes falcate-oblong, mid-lobe margin strongly undulate, and disk orange yellow, with three tuberculatus lamellae.

Type:— CHINA. Xizang: Medog county, Mt. Namjagbarwa region, inside the Yarlung Zangbo Grand Canyon National Nature Reserve , elev. ca. 2500 m. 29°27’N, 95°50E, 25 July 2020, Wu & Wang VTP00009089 (holotype PE!) .

Description: Terrestrial. Plants 50–60 cm tall. Pseudobulb globose, ca. 2 cm in diam., with 3 sheaths. Leaves 3– 4, both side glabrous, sheaths forming pseudo-stem at base, blade elliptic or obovate-lanceolate, 18–23 × 8–10 cm wide, margin undulate, apex acute, petiole 3–7 cm long. Scape arising from leaf axil, erect, 50–60 cm, peduncle densely finely puberulent; raceme 10–18 cm long, laxly ca. 4–7-flowered; floral bracts ovate-lanceolate, densely finely puberulent, apex acute. Flowers yellow, lip orange yellow. Pedicel and ovary 1.8–2.0 cm long, densely finely puberulent. Dorsal sepal elliptic, 2.5 × 1.5 cm, 3–5-veined, abaxially densely finely puberulent, apex acuminate; lateral sepals oblong-lanceolate, 2.8 × 1 cm, 3–5-veined, abaxially densely finely puberulent, apex acuminate. Petals oblong-lanceolate, 2.5 × 1.3 cm, 3-veined, apex acute; lip adnate to base of column wings, spurless, 3-lobed, 2.1 × 1.4 cm; lateral lobes falcate-oblong, small, ca.0.6× 0.2 cm, apex obliquely truncate; mid-lobe nearly reniform or orbicular, margin strongly undulate, 2.0 × 1.6 cm, base clawed, apex usually emarginate and mucronate in sinus, disk orange yellow, with 3 tuberculatus lamellae, middle extending to apex. Column ca. 0.6 cm long, yellow, ventrally sparsely puberulent. Pollinia waxy, narrowly obovoid-globose. Fl. May to July. Fr. August to September.

Etymology: The epithet refers to the type locality in Yarlung Zangbo Grand Canyon, Medog County, Xizang, China. Chinese name: ḃḛạ布ǭṗ兰.

Distribution, habitat and ecology: Calanthe × yarlungzangboensis occurs in the undergrowth layer of the subalpine evergreen coniferous forest dominated by Tsuga dumosa Eichl. (1887: 1) in the mountainous area of southeastern Xizang, China. Four populations were found, with about 200 clusters.

Figures

FIGURE 4. Calanthe ×yarlungzangboensis. A. habitat; B. habit; C. individual; D. front view of flower; E. vertical view of flower; F. peduncle and floral bract; G. ovary and lip; H. perianth and bract; I. lip and column; J. pollinia.

FIGURE 5. Calanthe ×yarlungzangboensis. A. individual; B. front view of flower; C. ovary and column; D. pollinia; E. sepals and petals. (Drawn by Li-Jie Zhu)