Bulbophyllum menglaense Jian W. Li & X. H. Jin, 2017

Li, Jian-Wu, Yin, Jian-Tao & Jin, Xiao-Hua, 2017, Bulbophyllum menglaense (Orchidaceae), a new species from Yunnan, China, Phytotaxa 311 (1), pp. 97-100 : 97-99

Bulbophyllum menglaense Jian W. Li & X. H. Jin sp. nov. ( Figs. 1–2 )

Type: — CHINA. Mengla County, Yunnan Province. Epiphytic on tree or rocks in capped forest in karst regions, alt. 1200 m, 13 September 2016, Jian-Wu LI 4578 (holotype, isotype: HITBC!)

Diagnosis: Bulbophyllum menglaense is morphologically similar to B. cariniflorum and B. triste , but differs from them by pseudobulbs conical; scape longer than leaves; petals narrowly lanceolate, marings ciliate; stelidia lanceolate.

Epiphyte. Rhizome stout, ca. 3.0 mm in diam. Pseudobulbs very close along the rhizome, conical, 2.0–3.0 × 1.0–2.0 cm, bearing 2 leaves on the apex. Leaf deciduous in dry season (deciduous after flowering), leaf blade oblong, abaxially slightly white-green, 12.0–18.0 × 2.0– 3.5 cm, middle with a vein, vein concave adaxially, abaxially convex, apex acute, base contracted into petiole-like, petiole-like unconspicuous. Scape from the base of pseudobulb, 18.0–25.0 cm, longer than leaf, glabrous; raceme 5.0–9.0 cm, pendulous, densely many flowered; peduncle with 4–5 sheaths, sheath tubular, 1.0– 1.5 mm; floral bracts ovate-lanceolate, cymbiform, 3.0 × 1.5 mm, apex acuminate. Pedicel and ovary ca. 3 mm. Flowers pale purplish red, glabrous. Dorsal sepal ovate, cymbiform, 5.0 × 2.5–3.0 mm, 3-veined, entire, apex acuminate; lateral sepals oblong, cymbiform, 6.0 × 2.0 mm, 3-veined, mid-vein narrowly keeled abaxially, their lower edges connate to each other about 2/3 to apex, apex acute. Petals narrowly lanceolate, 4.0–4.2 × 0.6–0.7 mm, 1-veined, margins ciliate, apex acuminate. Lip ligulate, 2.5–2.7 × 1.7–1.8 mm, fleshy, base grooved, attached to end of column foot by an immobile joint, apex round. Column ca. 2.5 mm, with wings enlarged at upper part, ca. 0.2 mm high; column foot ca. 1.5 mm; stelidia narrowly lanceolate, ca. 1 mm; anther cap galeiform; pollinia 2. Capsule oblique ellipsoid, 12.0–15.0 × 5.5–7.0 mm.

Phenology:— Flowering from August to October.

Distribution and habitat: — Bulbophyllum menglaense is found in Mengla County, Yunnan Province, P. R. China. It is epiphytic on tree or rocks in capped forest in karst regions, at elevation 1100–1250 m, together with two congenerics, B. hirtum and B. muscarirubrum .

Conservation status: —Approximate 150 clusters of Bulbophyllum menglaense were discovered epiphytic on trees or rocks in two populations. However, both sites are surrounded by rubber plantations. Due to the booming rubber plantation in southern Yunnan, southwestern China, most forests in tropical regions have been destroyed and the same is being expected for the type locality of the new species. During our field survey from 2009 to 2016, capsules were discovered in these two populations every year, but young plants and seedlings have not been observed. Therefore, it was considered as Endangered (EN) under criterion according to IUCN categories and criteria ( IUCN 2016).

Taxonomic Notes: —Morphologically, Bulbophyllum menglaense is similar to B. cariniflorum Rchb.f. (1861: 253) and B. triste Rchb. f. (1861: 253) , but it can be easy distinguished from them, such as shapes of pseudobulbs, length of scape, margins of petals, etc ( Table 1).

Figures

FIGURE 1. Bulbophyllum menglaense (Edited by Rui Zhou, photo by Jian-Wu Li) A. Type specimen (fresh). B. Type specimen (dry).

FIGURE 2. Bulbophyllum menglaense (Edited by Rui Zhou, photo by Jian-Wu Li) A. Habitat. B. Flower. C. Inflorescence. D. Capsule. E. Dorsal sepal. F. Lateral sepals. G. Petal. H. Lip. I. Column with lip. J. Column and pollinia.