Bulbophyllum yarlungzangboense Jian W. Li, Xi L. Wang & X. H. Jin, 2019

Li, Jian-Wu, Wang, Xi-Long, Wang, Cheng-Wang, Pan, Bo, Song, Zhu-Qiu & Jin, Xiao-Hua, 2019, Bulbophyllum yarlungzangboense (Orchidaceae; Epidendroideae; Malaxideae), a new species from Tibet, China, Phytotaxa 404 (2), pp. 79-84 : 82-83

Bulbophyllum yarlungzangboense Jian W. Li, Xi L. Wang & X. H. Jin , sp. nov. ( Fig. 1–2 )

Diagnosis. Bulbophyllum yarlungzangboense is morphologically similar to B. gamblei and B. shweliense , but differs from them by having conical pseudobulbs, ovate-oblong leaves, 1.0– 1.3 cm long, ovate-rhombic petals with acute apex, triangular stelidia, apex acute, column foot with a V-shape cushion.

Type. CHINA. Bomi County, Tibet. Epiphytic on tree or moss rocks near riverside in Yarlungzangbo Grand Canyon, alt. 2037 m, E: 95°00´24˝, N: 30°01´34˝, 18 December 2017, Jian-Wu Li 5036 (holotype: HITBC!)

Description. Epiphytic. Rhizome slender, ca. 1 mm in diam., pseudobulbs 1.0– 1.2 cm apart from each other, slightly oblique, conical, 0.7–1.0 × 0.4–0.5 cm, carrying 1 apical leaf. Leaf blade ovate-oblong, 1.0–1.3 × 0.6–0.9 cm, apex emarginated, mid-vine concave adaxialy, convex abaxialy, base contract into petiole-like, petiole unconspicuous. Roots came out from base of pseudobulbs. Inflorescence slender, came out from base of pseudobulbs, exceeding leaves, 2.0– 2.5 cm long, ca. 0.6 mm in diam., with 2–3 sheaths, sheath ovate-triangular, apex acute, 2.0 × 3.0 mm, rachis ca. 2 mm long, umbellate with 1–4-flowers, flowers yellowish-green. Floral bracts ovate, 3.5–4.0 × 1.5–1.6 mm, apex acute; pedicel and ovary ca. 1.6 mm long; dorsal sepal lanceolate, 5.0 × 1.0 mm, apex acuminate, 3-vine; lateral sepals lanceolate, base slightly oblique, 6 × 2 mm at base, apex acuminate, 3-vine; petals ovate-rhombic, 1.5 × 1.0 mm, apex acute, 1-vine; lip flesh, ligulate, 2.5 × 2.0 mm, attached to the end of column foot by a moveable joint, apex obtuse, lateral edges slightly upright forming a groove on disc; column stout, ca. 0.5 mm long, column wings unconspicuous; stelidias triangular, ca. 0.4 × 0.3 mm, apex acute; column foot ca. 1.1 mm long, curved, base with a V-shape cushion; anther cap semi-obconic, middle concave; pollinia 4, in 2 pair.

Etymology. The new species is named after Yarlungzangbo Grand Canyon where it was discovered.

Phenology. Flowering from November to December.

Distribution and habitat. Bulbophyllum yarlungzangboense was found in Bomi County and Medog County, Tibet, China, epiphytic on trees or moss rocks near riverside in Yarlungzangbo Grand Canyon, with elevation 1700– 2100 m.

Note. Morphologically, Bulbophyllum yarlungzangboense is similar to B. gamblei and B. shweliense , but differs from them by conical pseudobulbs, shorter leaves, V-shape cushion on column foot, etc. (see table 1)

Figures

FIGURE 1. Bulbophyllum yarlungzangboense Jian W. Li, Xi L. Wang & X.H. Jin (draw from type specimen by Bo Pan) Note. A. Plant with inflorescence (type specimen). B. Flower. C. Flora bract. D. Dorsal sepal. E. Petal. F. Lateral sepal. G. Lip (with face and side view). H. Column foot (show cushion). I. Pollinia. (Bar: A = 1 cm; B–H = 1 mm; I = 2 mm)

FIGURE 2. Bulbophyllum yarlungzangboense Jian W. Li, Xi L. Wang & X.H. Jin (photographed by Jianwu Li) Note. A. Habitat. B. Plant with inflorescence (type specimen). C–D. Flowers.