2. 中国科学院大学, 北京 1000493;
3. 云南省普洱林业局, 云南 普洱 665000
2. University of Chinese Academy of Sciences, Beijing 100049, China;
3. Forest Bureau of Pu'er, Pu'er 665000, Yunnan, China
The genus Pholidota Lindl. ex Hook. was esta- blished by W. J. Hooker. It belongs to the subtribe Coelogyninae, subfamily Epidendroideae (Orchidaceae), and comprises about 30 species widespread in the tropical and subtropical regions of the Old World, extending from the Pacific Islands to northeast Australia, Malaysia, South-east Asia and southern China. Members of Pholidota are featured by the lip with a relatively short, boat-shaped hypochile, rather short and compact column. In China, 14 species have been recorded[4–6].
During our recent field survey in southern Yunnan, a species of Pholidota was discovered. After extensive morphological comparisons based on relevant literature[7–9] and herbarium specimens, it was identified as Pholidota advena (Par. & Rchb. f.) Hook. f., a new record to the Chinese orchid flora.
Pholidota advena (Par. & Rchb. f.) Hook. f., Fl. Brit. India 5: 846. 1890; Grant, Orch. Burma 160. 1895.——Coelogyne advena Par. & Rchb. f., Otia Bot. Hamb. 1: 47. 1878. 高褶石仙桃Figs. 1, 2
Type: Myanmar, Tenasserim, C. S. P. Parish 296 (holotype: K!, isotype: W).
Description: Epiphytic herb. Plants 10–20 cm high. Rhizomes stout, short with roots, 3–6 mm in diam. Roots few, arising from apex of rhizome. Pseudobulbs in cluster, ovoid-cylindric, tapering toward the apex, 2.2–5 cm long. Leaves 2 per pseudobulb, oblong-lanceolate, 7.5–11 cm, apex acuminate; petiole 0.7–2 mm long. Inflorescence a raceme, synanthous, arising from developed young leaves near base of last pseudobulb, 7–10 cm. Rachis more or less pendulous, more or less zig-zag, nearly straight, 5–10-flowered. Floral bracts persistent, ovate to ovate lanceolate, 8–12 mm, apex acute to obtuse, membranous. Flowers whitish, tinged with light green, not opening widely; pedicel and ovary 4–8 mm long. Dorsal sepal ovate, strongly concave, 5–8 mm long, apex obtuse to acute, 5-nerved; lateral sepals ovate- oblong, somewhat oblique, 8–10 mm long, apex acute. Petals spathulate to obovate, narrowed toward the base, 7–8 mm long, 3–4 mm wide. Lip broadly oblong in outline, contracted at apical 1/3 into hypochile and epichile; 7–8 mm long; hypochile cymbiform, 5–6 mm long, 3.5–4.5 mm wide, with 3–5 lamellate keels near base; epichile two-lobed, transversely elli- ptic, wider than hypochile, 2.3–2.5 mm long, central part with three swollen, more or less wavy keels which converge to the apex; lateral lobes semi- orbicular, apex obtuse. Column stout, 4.5–5 mm long, with a rather small, wing-like hood which is shorter than the stigma. Anther more or less transversely elliptic in outline. Pollinia 4 in 2 pairs, pear-shaped. Stigma 3–3.5 mm by 1.5–2 cm, narrowly elliptic in outline; rostellum more or less broadly band-like, semi-orbicular to semi-elliptic. Capsule not seen.
Phenology: Flowering was observed in mid- September.
Distribution and habitat: Previously recorded from Myanmar (Tenasserim), newly recorded from Ximeng Wa Autonomous County, Pu'er City, Yunnan Province, China, where it grows as an epiphyte on tree trunks along the river in the rainforest, at an elevation 800 m. a.s.l. Q. P. Wu 90 (IBSC).
Conservation status: The species has not been seen in the wild for many years since it was first discovered in Myanmar. Currently information is known only from one location with mature individuals confined to a small forest patch in Yunnan, China. Considering there are not enough information about the populations of this species at present, it is suggested that the species could evaluated as DD (data deficient). We hope our findings could receive extra conservation attention.
Notes: Pholidota advena was classified into a separate section Advena by de Vogel depending on its special morphological characteristics. This species shows some similarities to P. chinensis Lindl., but it differs in having a distinctive lip that has prominent keels in the hypochile and two-lobed epichile with three elevated, more or less wavy keels.
Acknowledgments We would like to thank curators and staff of the herbaria BM, E, IBSC, K, KUN, P and PE for providing ongoing access to their specimens or digital images. Special thanks are due to Dr. Shi-jin Li for guidance on photos processing.
HOOKER W J. Exotic Flora, Containing Figures and Descriptions of New, Rare or Otherwise Interesting Exotic Plants, Vol. 2[M]. Edin-burgh: W. Blackwood & London: T Cadell, 1825: 138.
PRIDGEON A M, CRIBB P J, CHASE M W, et al. Pholidota[M]//Genera Orchidacearum 4, Epidendroideae (Part one). Oxford: Oxford University Press, 2005: 76-81.
DE VOGEL E F. Revisions in Coelogyninae (Orchidaceae) Ⅲ, the genus Pholidota[J]. Orchid Monographs, 1988, 3(1): 1-78.
Chen S C, Wood J J. Pholidota[M]//Wu Z Y, Raven P H, Hong D Y. Flora of China, Vol. 25. Beijing: Science Press & St Louis: Missouri Botanical Garden Press, 2009: 335-339.
XU Z H, JIANG H, YE D P. The Wild Orchids in Yunnan[M]. Kunming: Yunnan Publishing Group Corporation and Yunnan Science & Technology Press, 2010: 275-281. (in Chinese).
LI L, QIN M, WANG W Y, et al. The taxonomic identities of Pholi-dota wenshanica and P. subcalceata (Orchidaceae, Coelogyninae)[J]. PhytoKeys, 2019, 136(1): 97-106. DOI:10.3897/phytokeys.136.46705
HOOKER J D. The flora of British India[M]. London: Chenopo-diaceae to Orchideae. L. Reeve and Co. Ltd, 1890: 844-847.
SEIDENFADEN G. Orchid genera in Thailand: XIII. Thirty-three Epidendroid genera[J]. Opera Bot, 1986, 89: 96-106.
SEIDENFADEN G. The orchids of Indochina[J]. Opera Bot, 1992, 114: 121-128.
IUCN. Guidelines for using the IUCN red list categories and criteria, version 14[M]. UK: Gland, Switzerland and Cambridge, 2019: 5-98.