Research Article |
Corresponding author: Guo-Qiang Zhang ( zhanggq@sinicaorchid.org ) Corresponding author: Zhong-Jian Liu ( zjliu@fafu.edu.cn ) Academic editor: Vincent Droissart
© 2019 Lin Li, Ming Qin, Wan-Yao Wang, Song-Jun Zeng, Guo-Qiang Zhang, Zhong-Jian Liu.
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, Qin M, Wang W-Y, Zeng S-J, Zhang G-Q, Liu Z-J (2019) The taxonomic identities of Pholidota wenshanica and P. subcalceata (Orchidaceae, Coelogyninae). PhytoKeys 136: 97-106. https://doi.org/10.3897/phytokeys.136.46705
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P. wenshanica S.C.Chen & Z.H.Tsi and P. subcalceata Gagnep. have long been recognized as synonyms of P. leveilleana Schltr. In the present study, detailed morphological comparisons suggest that specimens referred to as P. wenshanica and P. subcalceata differ significantly in both vegetative and floral characters from those of P. leveilleana. Here we resurrect P. wenshanica and P. subcalceata as independent species. Key diagnostic characters essential for delineating identities of these species are presented.
China, emended description, orchid taxonomy, Vietnam
The orchid genus Pholidota Lindl. ex Hook. was established by
The taxonomic status of the Chinese species P. wenshanica S.C.Chen & Z.H.Tsi (1988: 7) has long been in doubt. Soon after its publication in the same year, this species has been placed in synonym with P. leveilleana Schltr. (1913: 107) by
Comparison of Pholidota specimens collected from different localities in China showed those representing P. wenshanica could be distinguished from P. leveilleana on the basis of several morphological characters recognized in this study. Further investigation revealed that a Vietnamese species P. subcalceata, which has been treated as a synonym of P. leveilleana, also differs in its unique characters. The present paper includes confirmation of the validities of P. wenshanica and P. subcalceata, assessments of diagnostic characters of these species and descriptions of newly recognized diagnostic characters.
To clarify the taxonomic status of Pholidota wenshanica in China, morphological studies were performed using specimens deposited at herbaria E, GXMG, IBK, IBSC, KUN, P and PE, and online databases such as JSTOR Global Plants (http://plants.jstor.org) and Chinese Virtual Herbarium (http://www.cvh.ac.cn/), with special focus on the type specimens. The only type of P. wenshanica was thoroughly examined and compared with various specimens of P. leveilleana from China including some type materials of its synonym P. subcalceata from Vietnam. Relevant literature, including the protologue, was consulted. We also conducted field investigations in the type localities of P. wenshanica and P. leveilleana. Living plants were collected and transplanted to the nursery of South China Botanical Garden (
Pholidota wenshanica S.C.Chen & Z.H.Tsi was described based on a specimen collected from Wenshan County, Yunnan (
Pholidota leveilleana Schltr. was described by
The types and selected specimens of P. wenshanica (A–C), Pholidota leveilleana (D–F) and P. subcalceata (G–I) A holotype sheet of P. wenshanica B China, Guangxi, Longzhou, HK Kadoorie PT 714 (PE) C China, Yunnan, HK Kadoorie Team 2361 (PE) D holotype sheet of P. leveilleana E China, Guangxi, China-UK Expedition Team ASBK365 (IBK) F China, Guangxi, Y.S. Huang Y1229 (IBK) G Holotype sheet of P. subcalceata H isotype sheet of P. subcalceata I Vietnam, Kontum, L.V. Averyanov & al., VH 292 (P).
Based on our close examination of the type specimens of P. wenshanica (Fig.
Morphological examinations indicate significant differences among these species. P. wenshanica is easily distinguished from the other two species by fusiform-cylindrical pseudobulbs, much more slender (7−8 cm long) and well apart (2 cm intervals or distance), with two oblong-lanceolate leaves, up to 30 cm long and ca. 3.5 cm wide. In floral morphology, P. wenshanica can be readily distinguished from P. leveilleana by the flower number and size, as well as the details of flowers. The former has distinctly more (30–40) flowers arranged alternately on the almost straight rachis, whereas P. leveilleana has fewer (12–18) flowers on the weakly zig-zag rachis (Fig.
Morphological comparison of Pholidota wenshanica, P. leveilleana and P. subcalceata.
Characters | P. wenshanica | P. leveilleana | P. subcalceata |
Pseudobulbs | fusiform-cylindrical, 7–8 cm × 6–8 mm, 1.5–2 cm apart, two-leaved | ovoid to conical-ovoid, 2.5–4.5 × ca. 3.5 cm, almost densely placed, unifoliate | narrowly ovoid to broadly fusiform, 1.5–3.5 × ca. 2 cm, densely placed, two-leaved |
Leaves | lanceolate-oblong 25–30 × 3–3.5 cm | narrowly elliptic to elliptic-lanceolate 15–25 × 2–3.5 cm | linear to linear-lanceolate 15–30 × 1–2.5 cm |
Petiole | 3.5–4 cm long | 4.5–7 cm long | 4–8 cm long |
Inflorescence | peduncle 3.5–4 cm, raceme with 30–40 flowers; rachis almost straight | peduncle ca. 7 cm, raceme with 12–18 flowers; rachis weakly zig-zag | peduncle 3–4 cm, raceme with 18–25 flowers; rachis almost straight |
Lip | subovate when flattened, lateral lobes inconspicuous | broadly oblong when flattened, lateral lobes inconspicuous | subpandurate when flattened, trilobed, lateral lobes prominent |
Hypochile | deeply saccated, with 4 prominent fleshy keels or carinae | shallowly cupular, with 3 thickened veins | deeply saccated, with 3 thickened veins |
Epichile | transversely elliptic, apex deeply notched into 2 broadly rounded lobes | transversely oblong, apex shallowly emarginate | reniform-orbicular, apex emarginate and truncate-subbilobed |
Column | 2.5–3 mm, apex narrowly winged | 3.5–4 mm, apex broadly winged | 3 mm, apex broadly winged |
Stelidia | rounded, with obtuse teeth along the upper margin | sharp, with conspicuous acute teeth along the upper margin | short and rounded, with obtuse teeth along the upper margin |
An additional specimen’s survey indicates that several collections previously identified as P. wenshanica, such as China-UK Expedition Team ASBK365 (IBK) (Fig.
In distribution, both P. wenshanica and P. leveilleana are endemic to southwestern China. P. leveilleana occur in W to N Guangxi and S Guizhou. P. wenshanica is currently only found in SE Yunnan and SW Guangxi. P. subcalceata is endemic to southern Vietnam. The more or less disjunct distributions clearly indicate that P. wenshanica and P. subcalceata should be considered as distinct species.
Pholidota wenshanica S.C. Chen & Z.H. Tsi, Bull. Bot. Res. 8(1): 7, fig. 1. 1988. Type: – CHINA. Yunnan, Wenshan County, cult. in Hort. Bot. Beijing, 4 Dec. 1984, Z.H. Tsi 223 (holotype PE!).
Plants lithophytic, up to 35 cm high; rhizome creeping, terete, 8–10 mm in diam., enclosed by coriaceous scales. Pseudobulbs fusiform-cylindrical, 7–8 × 6–8 mm, 2 cm apart, tapering to based and top, smooth or longitudinally wrinkled when dried, base usually enclosed by coriaceous sheaths. Leaves 2 per pseudobulb, arising from pseudobulb apex, oblong-lanceolate, 25–30 × 3–3.5 cm, apex acuminate, base cuneate, lamina glossy green, more or less coriaceous; petioles 3–4.5 cm long. Inflorescence a racemose, proteranthous, glabrous, pendulous, 17–19 cm long; peduncle 3.5–4 cm long, very thin, covered by sterile bracts at base of rachis; rachis slender, 13.5–20 cm long, almost straight or weakly zig-zag, laxly 30–40-flowered; floral bracts broadly rhombic-ovate, papyraceous, 4 × 6 mm, folded along the midrib, caduceus at anthesis. Flowers pinkish white, ca. 5 mm in diam., lip salmon-pink, tinged with yellowish-brown or orangish-brown blotches. Pedicel and ovary 3–4 mm long. Sepals subequal; dorsal sepal elliptic, 5 × 3 mm, apex acute, obscurely 7-nerved; lateral sepals ovate, slightly oblique, 5–6 mm long, strongly keeled on the back, apex shortly acuminate, obscurely 7-nerved. Petals ovate, 4 × 3mm, apex obtuse, obscurely 3–5-nerved; Labellum subovate in outline, 4–5 long; hypochile deeply saccated, with 4 prominent fleshy keels or carinae; epichile transversely elliptic, 4–5 mm wide, margin inconspicuously undulate, apex deeply notched into 2 broadly rounded lobes. Column stout, 2.5–3 mm long; apex narrowly winged, foot absent; stelidia obtuse, up margin with an inconspicuous rounded wing near the apex; anther incumbent, top retuse to rounded; pollinia 4 in 2 pairs, connected by caudicles to a sticky substance, pyriform, ca 0.5 by 0.4 mm; stigma broadly ovate; rostellum large, broadly triangular. Flowering in late November and early December. Capsule not seen.
Pholidota wenshanica is currently known only from SE Yunnan (Wenshan) and SW Guangxi (Longzhou), China, where it grows as epiphyte on tree trunks or as lithophyte on somewhat shady slopes or on the edge of forests, often in exposed places, with elevations ranging from 1200 m to 1500 m a.s.l.
China. Yunnan, Malipo County, Tiechang Town, at 1500 m alt., 13 Dec. 1992, Tsi s.n. (PE). China. Yunnan, precise locality unknown, Nov. 2001, HK Kadoorie Team 2361 (PE). China. Guangxi Zhuang Autonomous Region, Longzhou County, May 2001, HK Kadoorie PT 714 (PE).
Pholidota leveilleana Schlechter, Repert. Spec. Nov. Regni Veg. 12: 107. 1913. Type: – CHINA. Guizhou (Kouy-tcheou), Huishui County, Tian sheng qiao (Tien-sey-kao), at alt. 900m, 8 May 1910, J. Esquirol 2088 (holotype E!).
Lithophytic or occasionally epiphytic plants with short and stout rhizomes, up to 30 cm high. Pseudobulbs borne close together, ovoid or conical-ovoid, often longitudinally sulcate, 2.5–4.5 cm × 8–12 mm, ca. 3.5 cm in diam., basally usually enveloped by scarious sheaths. Leaf solitary, arising from pseudobulb apex, narrowly elliptic or narrowly elliptic-lanceolate, 15–25 × 2–3.5 cm, papery, plicate, leaf vernation prominent, base contracted into a distinct petiole, apex short acuminate, lamina dark green to bluish green; petiole 4.5–8 cm. Inflorescence arising from base of mature pseudobulbs, often pendulous, 13–18 cm or longer; peduncle 4.5–7 cm long; rachis weakly zig-zag, laxly 12–18-flowered; floral bracts deciduous, elliptic or broadly ovate, papyraceous, 7 × 9 mm. Flowers pinkish white or salmon-pink, ca. 5 mm in diam., lip white or greenish white, tinged with orangish yellow or carmine red blotches, anther and stigma red; pedicel and ovary 3–4 mm. Sepals broadly ovate-elliptic, 5–7 × 4–6 mm, 7-veined, acute; lateral sepals dorsally carinate. Petals ovate-elliptic, 4–5 × 2.5–3 mm, 3–5-veined, obtuse; lip broadly oblong in outline, 5–6 × 3 mm, contracted into epichile and hypochile at apical 2/3; hypochile shallowly cupular in center, margin spreading horizontally, with 3 thickened veins extending from base to above middle; epichile transversely oblong or elliptic, 4–5 mm wide, apex emarginate, slightly undulate margined. Column 3.5–4 mm, apex broadly winged; stelidia sharp, with conspicuous acute teeth along upper margin; anther broadly elliptic in outline, top truncate to retuse; pollinia 4 in 2 pairs, connected by caudicles to a sticky substance, pyriform, ca 0.5 by 0.4 mm; stigma suborbicular; rostellum semi-orbicular. Flowering in April and May. Capsule narrowly obovoid, ca. 2 cm × 5–6 mm; fruiting pedicel 2–3 mm. 1.2–1.5 cm in diam.
Pholidota leveilleana is endemic to N and W Guangxi (Luocheng, Du’an, Jingxi, Nandan, Huanjiang, Tian’e, Fengshan, Napo), S Guizhou (Huishui), China, where it grows as lithophyte in sparse forests and shaded rocks, with elevations ranging from 500 m to 900 m a.s.l.
China, Guangxi Zhuang Autonomous Region, Hechi City, Luocheng Molao Autonomous County, Xunle Miao Ethnic Township, 11 Mar. 2013, Luocheng County Exped. 451225130311036LY (GXMG, IBK); Luocheng Mulao Autonomous County, 23 Jun. 1939, W. Chen 84075 (PE). Guangxi Zhuang Autonomous Region, Hechi City, Huanjiang Maonan Autonomous County, Xunle Miao Ethnic Township, 26 Apr. 2013, Huanjiang County Exped. 451226130426003LY (GXMG, IBK); Huanjiang Maonan Autonomous County, Mulun Natural Reserve, 25 Apr. 2008, W.B. Xu & Y. Liu 08025 (IBK); Mulun Natural Reserve, 25°06'43"N, 108°00'13"E, 27 Dec. 2008, W.B. Xu, Y.Y. Liang, Y.S. Huang & X.X. Ye, Liuyan 0156 (KUN); Huanjiang Maonan Autonomous County, Mulun Town, NE Zhonglun, 10 Aug. 1994, Mulun Exped. M0117 (PE). Guangxi Zhuang Autonomous Region, Tian’e County, 5 May 1997, China-UK Expedition Team ASBK365 (IBK); Tian’e County, limestone Mt. at the junction of Lingdang and Liupai Town, 10 Aug. 1958, Z.T. Li 601198 (PE). Guangxi Zhuang Autonomous Region, Du’an Yao autonomous County, Shangfu Township, Y.K. Li P01539 (IBSC, PE). Guangxi Zhuang Autonomous Region, Fengshan County, Jinya Town, 24°38'4326.50"N, 106°45'00.96"E, 29 Mar. 2013, H.Z. Lv, L.H. Liu & H.F. Chen 451223130329080LY (GXMG). Guangxi Zhuang Autonomous Region, Nandan County, Lihu Town, 26 Jun 1937, C. Wang 40914 (IBSC, PE). Guangxi Zhuang Autonomous Region, Jingxi County, Sanhe Town, 15 Apr. 2012, Y.S. Huang Y1229 (IBK); Jingxi County, Renzhuang Town, 14 Sep. 2006, Y. Liu & W.B. Xu 0153 (IBK); Jingxi County, Longbang Town, Damo Village, 23 Apr. 2011, F.Y. Huang & Z.H. LV LHZJX0248 (GXMG). Guangxi Zhuang Autonomous Region, Napo County, Chengxiang Town, 12 Apr. 1998, H.N. Qin & al. 506 (IBSC, PE). Guangxi Zhuang Autonomous Region, Luchen (Luocheng?), 27 May 1928, anonymous 5405 (IBSC; PE); Guangxi Zhuang Autonomous Region, precise locality unknown, 25 Aug. 1935, S.P. Ko 55619 (PE). CHINA. Guizhou (Kouy-tchou), Dushan County, 13 Jul. 1959, Lipo Expe.1072 (PE).
Pholidota subcalceata Gagnepain, Bull. Mus. Natl. Hist. Nat., sér. 2, 22: 508, 1950.
Vietnam. Annam, North Kon Tum, near Moi village, at 1000–1500 m alt., 25 Nov. 1941, M. Poilane 32058 (holotype P! Isotype P!). Fig.
Pholidota subcalceata is endemic to the Central Highlands of southern Vietnam, north to Kon Tum, south to Lam Dong, where it grows as epiphyte on old trees in montane broadleaved forest in open areas and along streams, and occasionally grows as terrestrial herb, with elevations ranging from 1000–1800 m a.s.l.
Vietnam. Prov. Lam Dong, distr. Lac Duong, municipalite Da Chay, 35 km to NE from Dalat city, 12°08'N, 108°39'E, at 1450 m alt., 19 Mar. 1997, L.V. Averyanov, N.Q. Binh & P.K. Loc, VH 2897 (P). Vietnam. Prov. Lam Dong, distr. Lac Duong, municipalite Da Chay, 35 km to NE from Dalat city, 12°09'N, 108°41'E, at 1700–1800 m alt., 7 Apri. 1997, L.V. Averyanov, N.Q. Binh & P.K. Loc, VH 3753 (P). Vietnam. Prov. Lam Dong, distr. Lac Duong, municipalite Da Chay, 26–28 km to NE from Dalat city, 12°07'N, 108°36'E, at 1500–1700 m alt., 4 Oct. 1997, L.V. Averyanov, N.Q. Binh & P.K. Loc, VH 3842 (P). Vietnam. Prov. Kon Tum, NW slopes of Ngoc Linh mountain system, at 1600 m alt., 23 Feb. 1995, L.V. Averyanov & al., VH 290 (P); L.V. Averyanov & al., VH 291 (P); L.V. Averyanov & al., VH 292 (P); L.V. Averyanov & al., VH 294 (P);
The authors would like to thank Prof. Dr. Ming Cao and Ms. Qing-Song Xu for their assistances in the field work. Thanks are also due to the curators and staff of E, GXMG, IBSC, IBK, KUN, P and PE for permission to consult specimens or to access digital images. This research was financially supported by grants from 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).