Corresponding author: Xiao-Ke Xing (
Academic editor: Xiao-Hua Jin
Myanmar is known for its high species richness of genus
Liu Q, Zhou S-S, Li R, Tan Y-H, Zyaw M, Xing X-K, Gao J-Y (2020) Notes on the genus
The genus
This genus includes around 62 species distributed from Andamans, Sri Lanka, India and the Himalayas eastwards to southern China, Indochina and southern Japan and southwards to the Philippines and Indonesia, of which many species are narrow endemics and there is a major centre of diversity in the South-East Asian archipelago (
During our field investigations in Myanmar since 2015, a total of eight species of
Morphological observations of these species were based on living plants and 2–3 fertile specimens (kept in the herbaria of HITBC) or illustrations in original published papers (
INDIA. West Kameng Distinct, tropical rain forest, about 150 m a.s.l., epiphytic on tree trunks. A. N. Rao
Epiphytic herbs. Stem, erect, 4.0 cm long and 1.0 cm in diameter, with 3–4 leaves. Leaves nearly basal, distichous, oblong, 8.0–15.0 × 1.7–2.3 cm, slightly fleshy or leathery, apex obtuse and unequally 2-lobed. 1–4 inflorescences from base of stem, sub-umbellate, often 8–10-flowered; peduncle straight, 1–2 cm, stout, with 2 cupular sheaths. Flower yellow or yellow green, with dark brown or purplish spots. Sepals similar, oblanceolate, 6.8–7.0 × 3.2–3.5 mm, base contracted, apex obtuse. Petals oblanceolate, 6.2–6.5 × 2.3–2.5 mm, apex obtuse. Lip with an epichile and a saccate hypochile; epichile triangular, 2.5–3.0 × 5.4–6.0 mm, fleshy, adaxially glabrous, with a central cushion, margin irregularly fimbriate or erose, apex rounded; hypochile cupular, ca. 6 mm tall, ca. 4 mm in diameter, white tinged with pale yellow at bottom, outside with 3 ridges. Column ca. 4 mm, stout; rostellum deeply 2–lobed; pollinia 2, ca. 1.0 mm in diam.; stipe elongate, ca. 2.0 mm; anther cap nearly subglobose, apex narrowed into a beak. Fruit cylindrical, ridged, 5–6 cm in length, 1.2–1.4 cm in diameter.
Flowering occurs in October and November.
MYANMAR. Kachin State. Putao County, Wasadam village, tropical forest, 750 m a.s.l., epiphyte on the trunk of riparian trees, 14 Sep 2016,
INDIA. Jalapahar, Darjeeling (West Bengal), about 2200 m a.s.l., epiphytic on tree trunks. 29 Oct 1982, A.P. Das 823 (holotype: CAL!)
Epiphytic pendulous herb. Stem often branched, pendulous and usually 8.0–15.0 cm long with 0.4–0.5 cm internodes. Leaves distichous, blade oblong or falcate-lanceolate, 2.0–4.0 × 0.4–0.9 cm, apex acute and unequally 2-lobed. Inflorescence corymb, 4–6-flowered; peduncle 1.2–1.3 cm, upper part broader, lower part with 2 cupular sheaths with purple-red spots; floral bracts ovate-triangular, ca. 3.0 , membranous; pedicle and ovary yellow-green with purple-red spots, 1.0–1.2 cm long. Flowers yellowish or yellow, with purple blotches; epichile of lip white with sparse purple spots. Dorsal sepal oblong-elliptic, concave, 5.0–6.5 × 3.6–4.5 mm, apex obtuse; lateral sepal similar to dorsal sepal, 6.2–6.5× 3.2–4.0 mm, apex obtuse; petals sub-obovate, 5.5–6.5 × 3.5–4.2 mm, apex rounded. Lip with distinct partition between wide epichile and a saccate hypochile; epichile reniform, 4.0–4.9 × 8.0–9.0 mm, adaxially glabrous, with a slightly diamond-shaped central cushion covered with small brown spots and 2 conic calli near base, margin entire or slightly denticulate, emarginate at apex; hypochile cupular, laterally compressed, 7.2–7.8 mm tall, 5.8–6.2 mm in diameter, apex rounded. Column stout densely with purple spots, ca. 2 mm; anther cap galeate with recurved acuminate apex, 2.0 × 2.2 mm; pollinia 2, ca. 1.0 mm in diam.; stipe elongate, ca. 2.0 mm; rostellum bilobed with acuminate apex. Capsules cylindrical with 3 ridges, ca. 2.0 × 1.2 cm.
Flowering occurs in April to October.
MYANMAR. Chin State. Natma Taung (Mt. Victoria) National Park, 2750 m a.s.l., epiphyte on the trunk of Alpine
Only a single specimen and illustration of this species previously existed, on which the original description was based (
MYANMAR. s. coll., s. n. (Holotype: K!)
Epiphytic herbs. Stem 1.0–1.5 cm, stout, with 4–5 leaves. Leaves nearly basal, distichous, oblong, 15–20 × 3.5–4.5 cm, slightly fleshy or leathery, apex obtuse and unequally 2-lobed. Inflorescences 1–4, from base of stem, sub-umbellate, often 4–6-flowered; peduncle straight, 1.5–2.5 cm, stout, with 2 cupular sheaths. Flower with yellow sepals and petals and white labellum, all dense with purplish spots. Sepals similar, spatulate, 11.8–12.5 × 4.2–5.4 mm, base contracted, apex obtuse. Petals spatulate, 11.5–11.7 × 4.0–4.2 mm, apex obtuse. Lip with an epichile and a saccate hypochile; epichile subtriangular, 5.0–5.2 × 15.1–15.4 mm, fleshy, adaxially glabrous, with a central cushion with a yellow blotch, margin irregularly erose, apex acute; hypochile subglobose, ca. 8 mm tall, ca. 8.4 mm in diameter, white tinged with yellow at bottom, outside with 5 ridges. Column ca. 3 mm, stout; rostellum deeply 2–lobed; pollinia 2, ca. 1.2 mm in diam.; stipe elongate, ca. 1.5 mm; anther cap nearly subglobose, apex narrowed into a beak.
Flowering occurs in August and September.
MYANMAR. Kachin State. Putao County, Naungmeng town, tropical forest, 700–800 m a.s.l., epiphyte on the trunk of riparian trees, 8 August 2017,
The orchid flora of Myanmar is highly diverse but poorly known due to very few comprehensive studies. According to our current knowledge, about 800 orchid species are distributed in Myanmar (
Although the genus of
1 | Hypochile strongly dorsiventrally compressed from middle to tip, subtruncate and concave at tip |
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– | Hypochile subglobose or cupular, not dorsiventrally compressed |
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2 | Hypochile subglobose and laterally compressed |
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– | Hypochile subglobose or cupular, not compressed |
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3 | Stem erect |
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– | Stem pendulous |
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4 | Sepals and petals oblanceolate, epichile triangular without central cushion, epichile margin irregularly fimbriate or erose |
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– | Sepals and petals spatulate, epichile subtriangular with central cushion, epichile margin lacerate or erose |
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5 | Epichile densely haired adaxially and with a cavity at base |
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– | Epichile glabrous without cavity at base |
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6 | Flowers size 2–3 cm in diam., hypochile subconic or subglobose |
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– | Flowers size 1–1.8 cm in diam., hypochile galeate |
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7 | Stem stout and leaf over 5 cm in length |
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– | Stem slender and leaf less 3 cm in length |
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8 | Flower large (1.8–2.0 cm in diam.) and epichile margin entire |
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– | Flower small (0.6–0.8 cm in diam.) and epichile margin erose or irregular toothed |
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9 | Epichile sub-elliptic, without central cushion and conic calli |
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– | Epichile sub-orbicular, with a central cushion, base with 2 conic calli |
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10 | Short (less than 15 cm) and stout stem, leaf apex unequally 2-lobed without awns, inflorescences corymb with 4–6-flowered |
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– | Long (more than 30 cm) and slender stem, leaf apex with 2 or 3 awns, inflorescences subumbellate with 2–4-flowered |
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This work was supported by the National Natural Science Foundation of China (Grant no. 31500164) and Southeast Asia Biodiversity Research Institute, Chinese Academy of Sciences (Grant No. Y4ZK111B01) to Q. Liu and CAS 135 program (Grant No. 2017XTBG-F03). We are grateful to Dr. Pankaj Kumar for access to literature and language modification.