Bulbophyllum linzhiense Liang Ma & S.P. Chen, 2020

Ma, Liang, Zhang, Sai, Zhou, Zhuang, Lan, Si-Ren & Chen, Shi-Pin, 2020, Bulbophyllum linzhiense (Orchidaceae, Malaxideae), a new species from China, Phytotaxa 429 (4), pp. 281-288 : 287

Bulbophyllum linzhiense Liang Ma & S.P. Chen , sp. nov. (林º石fi兰; Figs. 2 , 3)

Type:— China, Tibet Autonomous Region, Motuo, epiphytic on branches in forests, altitude 2039 m, 2 October 2017, Ma 20171042xz (holotype: FAFU!).

This new species is similar to B. rubrolabellum , from which it differs by its pseudobulbs 6–10 mm apart from each other, inflorescence 2–4-flowered, floral bracts ovate-lanceolate, 2.5–2.8 mm, membranous, apex acuminate, pedicel and ovary 3.0– 3.2 mm long, yellow-green flowers, lateral sepals lanceolate, contracted toward the apex, apex acuminate, lip slightly recurved, orange-red, ligulate, fleshy, 2.0 long, stelidia narrowly triangular, approximately 0.8 mm.

Rhizome creeping, 2.0–4.0 mm in diameter, covered with membranous tubular sheaths, rooting from base of pseudobulbs, roots spreading. Pseudobulbs 6.0–10.0 mm apart from each other, ovoid, 8.0–9.0 mm, 6.0–7.0 mm in diam., with a terminal leaf. Leaf sessile; blade oblong, 2.2–4.8 × 0.3–0.7 cm, leathery, apex obtuse. Inflorescences arising from base of pseudobulb, erect, 1.0– 1.5 cm; raceme shortened, umbel-like, 2–4-flowered; with 3 tubular sheaths; floral bracts ovate-lanceolate, 2.5–2.8 mm, membranous, apex acuminate. Pedicel and ovary longer than floral bracts, 3.0– 3.2 mm. Sepals and petals yellow-green; lip orange-red. Sepals free, subequal, 4.0–4.2 × 2.0– 2.2 mm; dorsal sepal ovate-lanceolate; lateral sepals lanceolate, contracted toward the apex, apex acuminate. Petals elliptic, 2.0–2.4 × 0.8–1.0 mm, apex acute; lip slightly recurved, ligulate, fleshy, 2.0 × 1.1 mm, hinged to end of column foot by a joint, adaxially minutely papillate, apex obtuse. Column yellowish-white, short, 0.8 mm long; stelidia narrowly triangular, approximately 0.8 mm; foot orange-red, ca. 1.2 mm, with free part ca. 0.5 mm; anther cap yellowish, nearly semi-globose, 0.5 mm wide; pollinia 4, two pairs.

Phenology: —Flowering from September to October.

Etymology: —The species epithet refers to Linzhi prefecture, where this new species was first found.

Distribution and habitat: — Bulbophyllum linzhiense is so far only known within Motuo, Xizang, China. It is epiphytic on trees at elevations of 2039 m at the edge of evergreen Broad-leaved forests.

Conservation status: — Bulbophyllum linzhiense is known only from the type locality, and found in partially collapsed trees. A small number of plants were found around the temple, but not elsewhere. In addition, the local government has begun repairing the temples, hauling wires to the temples and destroying the forest around the temples, fearing that it might affect the species. Its endangered status should be evaluated as CR (critically endangered), according to the IUCN (2017).

Figures

FIGURE 2. Bulbophyllum linzhiense Liang Ma & S.P. Chen. A. Labellum. B. Dorsal sepal. C. Petal. D. Lateral sepal. E. Column and lip, side view. F–G. Pollinarium H. Plant.