Dendrobium bannaense Y.Q. Tian & Y.B. Huang, 2017

Tian, Ying-Qiu, Li, Ling, Yang, Yu-Ling & Huang, Yu-Bi, 2017, Molecular and morphological evidence for Dendrobium bannaense (Orchidaceae; Epidendroideae), a new species from China, Phytotaxa 328 (1), pp. 67-76 : 73-75

Dendrobium bannaense Y.Q. Tian & Y.B. Huang , sp. nov. (DZAEHffi; Figs. 4 , 5 )

Type:— China. Yunnan (Āffl): Banna ( DZAE), epiphytic on tree trunks in forests, 750 m, 6 May 2014, Liu 7819 (holotype: NOCC!).

Diagnosis:—This new species is similar to Dendrobium parishii , but differs in having a white lip with purplish stripes and without a deep purple blotch on either side, an ovate narrowly elliptic dorsal sepal, ovate-oblong lateral sepals, ovate-elliptic petals that are 2.8 × 1.3 cm, and the nearly broadly obovate lip that is 3.1 × 4.0 cm, with denticulate margin, and the disk with 3 longitudinal ridges, extending from base to upper-middle part, the lower-middle part being thickened and swell to callus shape at the joint of lip and claw.

Epiphytic herbs. The plant 3.0–9.0 cm; stems ascending or erect, 3.0–9.0 cm long, and 5.0–8.0 mm in diameter, upper part curved, unbranched, with internodes 0.5–1.7 cm. Leaves leathery, narrowly oblong, 3.5–5.5 × 0.7–1.2 cm, apex obtuse and unequally bilobed; leaf sheath white membranous. Inflorescene lateral on old leafless stem, 1 flowered; peduncle nearly absent, 1 mm; floral bracts membranous, broadly ovate, 2.5 mm, apex acute. Pedicel and ovary purplish-brown, 3.1 cm. Flowers spreading, slightly scented, sepals and petals purple, lip white with purplish stripes, column white with purplish halo, anther cap purple. Dorsal sepal ovate narrowly elliptic, 2.8 × 1.0 cm, apex subobtuse; lateral sepals ovate-oblong, 3.0 × 1.0 cm, apex acuminate; mentum conic, 7.0 mm, apex obtuse. Petals ovate-elliptic, 2.8 × 1.3 cm, apex acute, base shortly clawed, margin denticulate; lip nearly broadly obovate, 3.1 × 4.0 cm, both sides embracing column below middle, both surfaces densely pilose, margin fimbriate denticulate; disk with 3 longitudinal ridges, extending from base to upper-middle part, lower-middle part thickened and swell as callus shape at the joint of lip and claw. Column 4 mm with a foot 7.0 mm; pollinia 4, oblong, in 2 pairs.

Flowering periods:— May.

Distribution and habitat:— Dendrobium bannaense is epiphytic on tree trunks in forests at 750 m in Banna, Yunnan Province, China.

Etymology:— The species epithet refers to the locality where this new species was first found.

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

Figures

FIGURE 4. Dendrobium bannaense Y.Q. Tian & Y.B. Huang. A. Flowering plant. B. Flower, front view. C. Dorsal sepal. D. Petal. E. Lateral sepal. F. Lip. G. Pollinarium.

FIGURE 5. Dendrobium bannaense. A. Flowering plant. B. Flower, front view. C. Flower, side view. D. Pollinarium.