Corresponding author: Xiaohua Jin (
Academic editor: V. Droissart
Aung YL, Mu AT, Jin X (2018)
In the continental part of southeast Asia, there are nine species of
All measurements of the new
MYANMAR. Kachin State: Putao Township, Hponkanrazi Wildlife Sanctuary, subtropical, evergreen, broad-leaved, montane forest, 2000 m a.s.l., 20 October 2014,
Plants autotrophic, terrestrial, 40–60 cm tall. Stem ascending, pubescent, 2–6-leaved. Leaves dark green, ovate-lanceolate, 6–7.5 × 3.2–4 cm, attenuate at apex, blade glabrous; petiole-like base and tubular sheath ca. 2.8 cm long. Peduncle pubescent, with 1 or 2 sheathing bracts, reddish-brown, ovate-lanceolate, 12–15 × 4–5 mm, pubescent, long acuminate; rachis pubescent, sub-densely 16-flowered; floral bracts reddish–brown, ovate-lanceolate, ca. 9 × 4 mm, as long as ovary, abaxially pubescent, long acuminate at apex. Flowers resupinate; dorsal sepal forming a hood with petals, dark greenish-brown, ovate, ca. 6 × 3 mm, acute at apex, abaxially pubescent; lateral sepals greenish-brown, elliptic, oblique, ca. 8 × 4 mm, acute at apex, abaxially pubescent. Petals obliquely ovate-falcate, ca. 6 × 3 mm, membranous, glabrous; lip light yellow, T-shaped, shallowly grooved along the mid-line, ca. 1 cm long; hypochile bisaccate, sac sub-globose, ca. 2 mm in diameter, containing a low median keel and a small, erect, blade-like and apically emarginate callus on each side; mesochile ca. 4 mm long, with a pair of dentate-pectinate flanges, each flange composed of three narrow filaments, ca. 4 mm long and one broad blade-like posterior filament, ca. 3 mm long; epichile bilobed, lobes erect, diverging at obtuse angle to each other, elliptic, ca. 5 × 3 mm, margin involute and consequently resulting in concave lobes, obtuse at apex. Column ca. 1 mm long, stout; anther acuminate in front, ca. 4 mm long; pollinia 2, clavate; stigma lobes confluent; ovary and pedicel cylindric, twisted, sparsely pubescent.
The new species is named after Putao, the northernmost town of Myanmar, near which it was discovered in a vast area of undisturbed mountain forest.
1 | Plant without green leaves, all leaves reduced to sheaths. Flowers usually not resupinate |
|
1' | Plant with green leaves, leaves fully differentiated. Flowers usually resupinate | |
2 | Epichile not deeply bilobed, broadly obovate to transversely oblong | |
3 | Mesochile with a pair of entire flanges (or slightly dentate), epichile nearly as wide as long |
|
3' | Mesochile with a pair of dentate flanges (or slightly dentate), epichile about twice as wide as long |
|
2' | Epichile deeply bilobed | |
4 | Mesochile with two pairs of laciniate flanges |
|
4 | Mesochile with one pair of dentate-pectinate flanges | |
5 | Ovary usually glabrous | |
6 | Bracts finely erose-ciliate, flowers usually yellow |
|
6' | Bracts entire, flowers usually white |
|
5' | Ovary (glandular-) pubescent, sometimes sparsely so | |
7 | Epichile bilobed with a pair of widely diverging lobules that are erect and concave |
|
7' | Epichile bilobed with a pair of diverging and flat lobules | |
8 | Leaves reddish-brown, labellum twisted |
|
8' | Leaves green above, labellum not twisted |
|
Myanmar lies in southeast Asia and is well endowed with biodiversity-rich areas such as tropical evergreen rainforest, coastal mangrove forest and subtropical montane forest. The northern part of Myanmar is situated in the ecological transition area of three global biodiversity hotspots, the Indo-Burma hotspot, Mountains of southwest China hotspot and Himalaya hotspot (
Special thanks are due to Vincent Droissart for his critical and helpful comments and suggestions on the manuscript. We also acknowledge Hubert Kurzweil for the substantial corrections/modifications he made during the first round review. This research was supported by grants from the Southeast Asia Biodiversity Research Institute, Chinese Academy of Sciences (Grant No. Y4ZK111B01) and the National Natural Science Foundation of China (Grant Nos. 31670194, 31620103902).