Research Article |
Corresponding author: Hai-Fei Yan ( yanhaifei@scib.ac.cn ) Corresponding author: Shi-Jin Li ( lisj@scib.ac.cn ) Academic editor: Murielle Simo-Droissart
© 2019 Lin Li, Shih-Wen Chung, Bo Li, Song-Jun Zeng, Hai-Fei Yan, Shi-Jin Li.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Li L, Chung S-W, Li B, Zeng S-J, Yan H-F, Li S-J (2019) Liparis napoensis (Orchidaceae), a new species from Guangxi, China. PhytoKeys 119: 31-37. https://doi.org/10.3897/phytokeys.119.32041
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Liparis napoensis, a new orchid species belonging to section Cestichis from Guangxi, China is described and illustrated. It occurs in the karst limestone forest. The new species is morphologically similar to L. viridiflora and L. somae, but can be readily distinguished by having narrowly oblong-falcate petals; flabellate-quadrate lip distinctly concave at base and emarginate at apex; conspicuously arcuate column with a pair of wedge-shaped wings.
Malaxideae, Napo County, orchid, section Cestichis, taxonomy
The genus Liparis L.C.
As traditionally delimited, Liparis section Cestichis Thouars ex
The limestone karst area is part of a global biodiversity hotspot. Floristic investigations of limestone areas in southwestern Guangxi, China from April 2012 to July 2015, have yielded the discovery of an interesting Liparis species of section Cestichis. Morphologically, this species is superficially similar in appearance to L. viridiflora (Blume)
A total of 450 herbarium specimens of Liparis species in the section Cestichis were examined from herbaria BM, E, HN, IBK, IBSC, K, PE and US (acronyms according to
CHINA. Guangxi Zhuang Autonomous Region, Baise City, Napo County, Yongning Village, Jinlongyan Cave, lithophytic on moss in monsoon evergreen broad-leaved forest, alt. 830 m, 31 May 2012, L. Li 1001, (holotype, IBSC!).
Liparis napoensis differs from its closest allies: L. viridiflora and L. somae in the clustered ovoid-cylindrical or narrowly pyriform pseudobulbs, narrowly oblong-falcate petals; a flabellate-quadrate lip with a distinctly concave base, an emarginate apex and erose margins; a conspicuously arcuate column with a pair of wedge-shaped wings.
Lithophytic herbs. Pseudobulbs clustered, ovoid-cylindrical or narrowly pyriform, 5–10 cm × 5–8 mm, attenuate toward apex, base covered with 3–4 fibrous remnant sheaths. Leaves 2, terminal, blade oblanceolate or oblong-spatulate, thin coriaceous, base contracted into a very short petiole less than 1 cm or subsessile, apex acute and minutely apiculate, 7–12× 1.5–2 cm. Inflorescence terminal, often recurved, 15–20 cm, densely racemose, pedunculate; rachis 10–15 cm with densely arranged numerous flowers; floral bracts linear-lanceolate, 3.5–4 mm, membranous, greenish-white. Flowers resupinate, spreading, 4–4.5 mm across, white, tinged with pale yellow in the centre; pedicel and ovary 3.5–4 mm, pale yellow or greenish-yellow. Dorsal sepal ovate-oblong, margins often revolute, apex obtuse, 2.5–3 × 0.8–1 mm, translucent white, becoming yellowish towards the base. Lateral sepals obliquely ovate-elliptic, margins often revolute, 2.5–3 × 0.8–1 mm, translucent white, becoming yellowish towards the base. Petals narrowly oblong-falcate, margins revolute, 2–2.5 × 0.3–0.5 mm, translucent white, becoming yellowish towards the base. Lip nearly flabellate-quadrate, 2–2.5 × 1.5–2 mm, base shallowly concave and distinctly recurved from the middle, indistinctly divided into hypochile and epichile; hypochile ecallose, adaxially slightly thickened and fleshy towards the margins on each side; epichile emarginate, apical margins inconspicuously erose, translucent white, furnished with pale yellow at base. Column terete, conspicuously incurved or arcuate above the middle, apex with 2 short, wedge-shaped wings, with the base slightly dilated, 1.0–1.5 mm long, greenish-white, tinged with pale yellow at base. Stigma concave, subelliptic. Rostellum approximately truncate, apex obtuse, yellowish. Anther terminal, 2-celled, persistent, compressed ovoid, ca. 0.5 mm long. Pollinia 4, hard, waxy, yellow, ca. 0.3 mm. Capsule obovoid-ellipsoid, ridged, 4–6 × 2–3 mm; fruiting pedicel 3–5 mm.
Endemic to Guangxi in China. Lithophytes in rocks crevices where soil or organic matter has accumulated at elevations from ca. 650 m to 900 m in karst limestone forest.
The epithet “napoensis” is derived from the type locality: Napo County, Guangxi, located at China’s southwest border, where the species was discovered.
Flowering and fruiting in January–February.
Based on careful field investigations in the past years, this species is rare and only known from the type locality. Plants grow in sparsely scattered groups and the known population of two colonies consists of only a few dozen individuals (density less than one plant per 20 m2). In addition, the location is not in a protected area and accessible to casual hikers. According to the guidelines for using the IUCN Red List Categories and Criteria (
The new species in its general appearance has some superficial similarity with Liparis viridiflora, but the latter differs in longer petioles, narrowly linear petals, ovate-oblong lip with a mucronate tipped apex and a column with rounded wings. It also superficially resembles L. somae, but is characterised by having ovoid-cylindrical or narrowly pyriform pseudobulbs, a flabellate-quadrate lip with a distinctly concave base and an emarginate apex. A detailed morphological comparison between L. napoensis and its closely related taxa L. viridiflora and L. somae is presented in Table
Characters | L. napoensis | L. somae | L. viridiflora |
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Growth habit | lithophytes | epiphytes | epiphytes or lithophytes |
Pseudobulbs | ovoid-cylindrical or narrowly pyriform | ovoid or clavate | elongate-cylindrical |
Leaves | oblanceolate or oblong-spatulate, apex acute and minutely apiculate | oblanceolate or spatulate, apex acute | linear-oblanceolate, apex acuminate and apiculate |
Petiole | less than 1 cm or subsessile | 2–3 cm | 1–4 cm |
Dorsal sepal | ovate-oblong | lanceolate | elliptic-oblong |
Lateral sepals | obliquely ovate-elliptic | obliquely ovate | ovate-elliptic |
Petals | narrowly oblong-falcate | linear | narrowly linear |
Lip | flabellate-quadrate, base concave, slightly thickened on each side, apex emarginate, apical margin inconspicuously erose | ovate, base slightly contracted, apex acute, apical margin slightly crisped-denticulate | ovate-oblong, base contracted, apex subacute or mucronate, apical margin slightly undulate |
Column | conspicuously arcuate, apex with 2 wedge-shaped wings | slightly arcuate, apex with 2 obtusely dentate wings | slightly arcuate, apex with rounded wings |
We sincerely thank Prof. Cao Ming (Guangxi Institute of Botany,