Dendrobium jizhuyeense Z. J. Li & Y. Zhang.

Liang, Meng, Chang, Ling-Ling, Wang, Jia-Xin, Zhang, Yu, Liu, Lei, Zhang, Ze & Li, Zhen-Jian, 2024, Dendrobium jizhuyeense (Orchidaceae; Epidendroideae) a new species from China: evidence from morphology and DNA, Phytotaxa 645 (1), pp. 77-84 : 82-83

Dendrobium jizhuyeense Z. J. Li & Y. Zhang. sp. nov. (Mn'叶石ffi; Figs. 2 , 3 , 4 )

Type:— China. Sichuan (四川): Ganzi Prefecture (ffss州), epiphytic on the rocks in the mountain forests, 1691 m. 16 May, 2016, Li 1018 (holotype: CAF!) .

Diagnosis: This new species is morphologically similar to D. hancockii but differs in the apex shape of its sepals and petals (apex rounded, vs. apex acute), rostellum of column (not obvious and yellow vs. obvious and white), length of leaves (3–7 cm vs. 6–11 cm).

Epiphytic herb; pseudobulbs erect, usually branching, clustered, 10–65 cm long and 2–6 mm in diameter. The base of the stems expands into hard wood, and the stem is spindle-shaped with longitudinal ribs and internodes 2–4 cm long. Leaves thin and leathery, 3–7 cm in length and 0.5–1.4 mm in width, with blunt rounded tips and unequal 2-lobed sides. Raceme, thick, fragrant, spreading, golden yellow flowers. Dosal sepal ovoid, while the side sepals are oval. Petals obovate, and the lip obovate, the petal veins obvious. The anther cap is elliptical, with a smooth surface and a slightly orange yellow lip. The lip is 1.5–1.8 cm long and 1.2–1.5 cm wide. The lip is triple lobed, with lateral lobes surrounding the column. The middle lobe is densely covered with short papillary hairs.

Flowering period:— Flowering April–May.

Distribution and habitat:— Dendrobium jizhuyeense is epiphytic on the rocks and tree trunks in the mountain forests at 1200–2100 m in the southern Qinling Mountains, Liangshan Prefecture, Ganzi Prefecture, Aba Prefecture, Ya'an City and Leshan City in Sichuan Province, China.

Etymology:— The species name refers to the Chinese name for this plant used by local residents in Sichuan Province, China.

Conservation status:— Based on the World Conservation Union Red List Categories and Criteria (IUCN, 2001), D. jizhuyeense should be treated as endangered.

Figures

FIGURE 2. Dendrobium jizhuyeense Z. J. Li & Y. Zhang. A. Flowering plant. B. Leaf. C. Inflorescence. D. Flower, front view and side view. E. Anatomy of a flower: dorsal sepal, petal, lateral sepal, and lip. F. Column. G. Column, rostellum. H. Anther cap. I. Pollinarium. Drawn by Sun Ying-Bao.

FIGURE 3. Dendrobium jizhuyeense Z. J. Li & Y. Zhang.A. Flowering plant in cliff, B. Flowering plant in pot. C. Flower, front view. D. Anatomy of a flower: sepal, petal, and lip. E. Column. F. Column and pedicel. G. Leaf. Photographs by Zhen-Jian Li & Yu Zhang.

FIGURE 4. Dendrobium jizhuyeense (A) and Dendrobium hancockii (B, D), A. Flower of D. jizhuyeense, B. Flower of D. hancockii, C. Anther cap of D. jizhuyeense (right) and D. hancockii (left), D. Column of D. hancockii, E. leaf of D. jizhuyeense (up) and D. hancockii (down). Photographs by Zhen-Jian Li.