Corresponding author: Song-Jun Zeng (
Academic editor: V. Droissart
Li L, Ye D-P, Zeng S-J (2018)
Recently, based on phylogenetic studies, all genera previously proposed in subtribe
The high number of species in the genus
Morphological comparisons and assessments of
Diagnostic morphological characters distinguishing
Character |
|
|
|
---|---|---|---|
Floral bract | 6–6.5 mm, distinctly longer than pedicel and ovary. | 4.5–5 mm, distinctly longer than pedicel and ovary. | 5–6 mm, nearly as long as or slightly longer than pedicel and ovary. |
Scape | 5–6 cm, rachis about 6.5 cm, longer than scape | 10–13 cm, much longer than rachis | 4–8 cm, rachis about the same length |
Dorsal sepal | oblong-ovate or narrowly ovate, apex shortly aristate or apiculate, 4.5–5 mm × 1.0–1.5 mm | ovate, apex acute, 6.5–7 mm × 2.5–3 mm | broadly ovate, apex acute, ca. 7.0 × 3.5 mm, |
Lateral sepals | obliquely oblong-ovate, margins strongly involute, with the apex shortly caudate, 5.5–6 mm × 2.0–2.5 mm | obliquely ovate-lanceolate, margins not involute, apex acute, 7.5–8.0 × 3.5 mm | obliquely ovate-lanceolate, margins not involute, apex acute, ca. 8.0 × 4.5 mm |
Petals | apex with long filiform apices, ca. 3.0 mm long, usually contorted to spirally twisted | apex with filiform apices, ca. 1.8 mm long, not twisted | apex with cuspidate apices, ca. 0.8 mm |
Lip | ca. 2.8 mm long, significantly glandular-papillose and ciliolate at margins | ca. 5 mm long, not papillate or papillose at margins | ca. 6 mm long, somewhat papillate at margins, not ciliolate |
Lip auricles | narrow falcate, long acuminate with a sharp point | not falcate, rather obtuse at apex | narrow falcate, apex apiculate and unequally 2- or 3-toothed |
Column callus | absent | present, conical | absent |
Stelidia | subulate and twisted, exceeding operculum | subulate but not twisted, exceeding operculum | subulate and twisted, as long as or shorter than operculum |
CHINA. Yunnan Province. Menglian Dai, Lahu and Va Autonomous County (referred to as Menglian County), 1400–1600 m alt., 23 May 2014, L. Li 1209, (holotype, IBSC! isotype, IBK!).
Epiphytic herbs. Rhizome rigid, creeping, 2–3 mm thick. Pseudobulbs borne on rhizome at an interval of 3–5 cm, ovoid to narrowly ovoid, 2.2–3.5 cm high, base often covered with remnant fibrous sheaths. Leaf apical, single, coriaceous, oblong to linear-oblong, 12–14 cm × 1.8–2.2 cm, subsessile, apex retuse or minutely notched. Inflorescences developing from base of pseudobulb, with pendulous densely many-flowered raceme; scape 5 to 6 cm long, nearly completely enveloped by 4 or 5 sterile, broadly ovate sheaths; sheath 1.5–1.8 cm long, scaled, light brownish; rachis about 6.5 cm long, with many flowers spirally arranged into a compact spike-like cylindrical raceme, opening simultaneously; floral bracts light brownish, dry papyraceous, oblong-lanceolate, ca. 6.5 mm long, almost twice as long as the pedicel and ovary, apex apiculate; pedicel and ovary ca. 3.5 mm, longitudinally slightly grooved. Flowers resupinate, not much opening, with unpleasant fishy smell. Sepals 3–6-veined, greenish-yellow, without spots or stripes. Dorsal sepal oblong-ovate or narrowly ovate, 4.5–5.0 mm × 1.0–1.5 mm, 3-veined, abaxially sparsely papillate, apex shortly aristate or apiculate, often recurved. Lateral sepals obliquely oblong-ovate, 5.5–6 mm × 2.0–2.5 mm, 5–6-veined, abaxially sparsely papillate, base adnate to column foot, margins strongly involute, with the apex shortly caudate, loosely adhering along the lower edges, forming an ovoid sac. Petals pale greenish-yellow, obliquely and broadly-based triangular, apex long acuminate, tapering into a long filiform or threadlike tail, usually contorted to spirally twisted, 2.0–2.2 mm × 0.8–1.0 mm near the base, with a tail 2.8–3.0 mm long, margins somewhat irregularly denticulate or erose. Lip yellowish-orange or deep golden yellow, fleshy, oblong narrowly ovoid, 2.5–2.8 mm × 1.3–1.5 mm, mobile on a thin ligament, recurved near the base, conspicuously auriculate at the base; disc with a longitudinal central groove, apex rounded or obtuse; auricles narrowly falcate, arching forward and gradually tapering to a long sharp point at the apex; densely glandular papillose on both sides and conspicuously ciliolate along margins, whitish. Column greenish-yellow, subcylindric, 2.0–2.2 mm tall; foot ca. 1.5 mm; stelidia well-developed and subulate, ca. 1.2 mm, often twisted inwards, equalling or slightly exceeding operculum, with a sharp point along the upper margin. Anther abaxially with a rounded crest, golden-yellow. Pollinia 4, the inner ones more than half as long as the outer ones.
So far known only from Menglian County in southwest Yunnan Province, China, growing as an epiphyte amongst mosses on the tree trunk near the edge of river in rather exposed circumstances in subtropical evergreen broad-leaved forest.
The specific epithet comes from the Ancient Greek word
Flowering observed in December.
We sincerely thank Peter O’Byrne (FRIM) for comments on an earlier version of this article and Ms. Yun-Xiao Liu (IBSC) for the line drawing. We are also grateful to the editor and reviewers for their critical comments and helpful suggestions to the manuscript. Funding for this research was provided by the National Natural Science Foundation of China (No. 31770215) and Science and Technology Basic Work, Project of the Ministry of Science and Technology, China (No. 2013FY112100).