Phalaenopsis medogensis X.H.Jin & C.B.Ma, 2022

Ma, Chong-Bo, Wang, Xi-Long, Chen, Wen-Shuai, Liu, Zhen & Jin, Xiao-Hua, 2022, Phalaenopsis medogensis (Orchidaceae, Epidendroideae, Vandeae), a new species from Xizang, China, PhytoKeys 214, pp. 39-46 : 39

Phalaenopsis medogensis X.H.Jin & C.B.Ma sp. nov.

Figs 3 , 4 墨脱蝴蝶兰

Type.

China. Xizang Autonomous Region, Nyingchi City , Motuo County, elev. 800 m, 18 Apr 2022, Xiaohua Jin, Chongbo Ma & Tiankai Zhang 38519 (holotype PE!, isotype, PE!) .

Diagnosis.

Phalaenopsis medogensis is morphologically close to P. deliciosa , P. gibbosa and P. lobbii , but readily distinguished from them by its column foot having a pair of triangular wings, and a lip with concave subrectangular lateral lobes, that are white with a deep purplish-red spot in their lower part and hairy and pale yellow with dense rust-coloured spots in their upper part, and a rhombic mid-lobe with a fleshy horned appendage at base and grooved in the centre (Table 1 ).

Epiphytic plant. Roots greenish, elongate, flattened, densely verrucose and prostrate along the twigs or trunk. Stem very short. Leaf 1, oblong-elliptic, 7-10 × 3-4 cm. Inflorescences 1 or 2, suberect or arching, ca.12 cm long, unbranched, laxly 5-6 flowered; floral bracts ovate-triangular, 5-6 mm long. Flowers 1-1.2 cm in diameter, yellow; sepals and petals pure yellow, lacking spots or other colouration. Dorsal sepal similar to petals, elliptic, ca. 7-8 × 5 mm; lateral sepals broadly triangular, ca. 10 × 6 mm. Petals long elliptic, ca. 9 × 5 mm. Lip 3-lobed; lateral lobes subrectangular, concave, almost boat-shaped, 2 × 4 mm, lower part white with a deep purplish-red spot and hairy, upper part pale yellow with dense rust-coloured spots; mid-lobe rhombic, ca. 10 × 7 mm, disc grooved, base with a fleshy protuberant appendage; appendage with 2-3 teeth on either side, apex with two long horns. Column subparallel to mid-lobe, ca. 5 mm long; column foot ca. 4 mm long, with triangular wings on both sides; anther cap yellow, hemi-spherical.

Etymology.

The epithet " Phalaenopsis medogensis " refers to the type locality of the new species, Medog County, Nyingchi City, Xizang Autonomous Region, China.

Distribution and habitat.

Phalaenopsis medogensis is currently known only from the type locality in Motuo, Xizang, China. It is epiphytic on trunks and twigs at elevations of 700-900m along the hot valley of the Yarlungzangbo River.

Phenology.

Flowering in March to April.

Conservation status.

Phalaenopsis medogensis grows in the tropical rain forest in Motuo County. At least one population of about 30 plants was discovered during our fieldwork. The habitat has been significantly damaged due to the development of agriculture and road construction. We tentatively assessed the risk of extinction of the Phalaenopsis medogensis as Critically Endangered (CR) under criteria B2ab(i, ii, iii, iv, v) according to the IUCN criteria version 15.1 ( IUCN 2022).

Note.

P. medogensis is similar to three species in subgen. Phalaenopsis Parishianae , namely, P. deliciosa , P. gibbosa and P. lobbii , but is readily distinguished from them based on morphological characters given in Table 1 .

Figures

Figure 3. Habitat and plants of Phalaenopsis medogensis.

Figure 4. Flowers of Phalaenopsis medogensis X. H. Jin & C. B. Ma, sp. nov. A front view of flower B lateral view of flower C front view of flower, showing basal part of lip D lateral view of column, ovary and pedicel E lip, side view F lip, dorsal view G column and column foot H dorsal sepal I petal J lateral sepal K anther cap. Photographed by Xiaohua Jin and Chongbo Ma.