Research Article |
Corresponding author: Houcheng Xi ( xihoucheng@xtbg.ac.cn ) Corresponding author: Shuai Chang ( changshuai@mail.kib.ac.cn ) Academic editor: Marco Pellegrini
© 2019 Zhiwei Wang, Wenguang Sun, Houcheng Xi, Shuai Chang.
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:
Wang Z, Sun W, Xi H, Chang S (2019) Dysosma villosa (Berberidaceae), a new species from Guizhou, Southwestern China. PhytoKeys 124: 77-85. https://doi.org/10.3897/phytokeys.124.34435
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A new species, Dysosma villosa Z.W.Wang & H.C.Xi, is described and illustrated based on collections from the Yueliang Mountains in Congjiang County of Guizhou, Southwestern China. It is morphologically similar to D. difformis (Hemsl. & E.H.Wilson) T.H.Wang ex T.S.Ying, but can be easily distinguished from D. difformis by its inflorescences bearing a greater number of flowers (5–13 vs. 2–5), white-villous stems, petioles, and abaxial leaf blade, and stigma dark purple-red. In addition, we also compare this new species to the three species of Podophyllum (i.e., P. glaucescens J.M.H.Shaw, P. hemsleyi J.M.H.Shaw & Stearn, and P. trilobulum J.M.H.Shaw) which are insufficiently known and listed as putative members of Dysosma in Flora of China. Dysosma villosa can also be easily distinguished from P. glaucescens (7-flowered; to 40 cm tall) and P. hemsleyi (4-flowered; to 40 cm tall) by its inflorescences bearing a greater number of flowers, relatively smaller stature (9–23 cm tall), stems, petioles and abaxial leaf blade densely white-villose. Although the stems and petioles of P. trilobulum also possess fine short hairs, it can be easily distinguished from D. villosa by its trilobulate leaves, inflorescence with fewer flowers (2–5), and the position of inflorescence (inserted at or above midpoint on petiole of upper leaf).
Asia, Berberidaceae, Dysosma, Podophylloideae, Podophyllum, Ranunculales
Dysosma Woodson, a small genus of Berberidaceae, has long been used in traditional herbal medicine in East Asia due to the presence of podophyllotoxin, which has important biological activities, such as treating external genital warts (
During a field trip to the Yueliang Mountains, Congjiang County, Guizhou Province, Southwestern China, in May 2015, an unknown species with densely white-villous stems, petioles and abaxial leaf blade, and dark purple-red stigma was found. After a detailed examination of the characters of our material and possible closely similar species in Dysosma (including the three species of Podophyllum which are putative members of Dysosma), we concluded that these specimens actually represent an undescribed species. Thus, due to its uniqueness in characters, it is formally described by us, below.
Field investigations were conducted in the locality of the type specimens and other adjacent areas of Guizhou. The morphological description of the new species was based on an examination of the dried specimens in herbaria and living plants in the field. The comparison with morphologically similar species was based on an extensive check of specimens deposited in A, E, GH, PE, KUN, IBSC, HIB, HGAS, IBK and NAS, as well as the protologues and descriptions in related literature (
Dysosma villosa is most similar to D. difformis (Hemsl. & E.H.Wilson) T.H.Wang ex T.S.Ying, but differs from the latter by its inflorescences generally with more flowers (5–13 vs. 2–5), white-villous petioles, stems and abaxial leaf blade and dark purple-red stigma.
CHINA. Guizhou: Congjiang County, Guanghui Town, Jiaya Village, Yueliang Mountains, alt. 1105 m, 25.636N, 108.293E, 09 May 2015, Z.W. Wang & H.C. Xi WAZW15016 (holotype: CSH barcode CSH0160399!; isotype: KUN!).
Herbs 9–23 cm tall. Rhizomes usually terete, slender, with numerous fibrous roots. Stems erect, branched, pale green, white-villous. Leaves alternate, obliquely peltate; petioles 6–12 cm long, white-villous; blades 9–17 × 13–23 cm, papery, abaxially pale green, densely white-villous, adaxially deep green, glabrous, base not deeply divided or undivided, margin sparsely denticulate. Umbels 5–13-flowered, sessile, emerging near the base of the leaf blade. Flowers pendulous, pedicels 1.6–2.2 cm long, apically gibbous, sparsely white-villous; sepals 1.4–2.2 cm × 1–4 mm, oblong-lanceolate, pale green, abaxially pubescent, adaxially glabrous, apex acuminate; petals 4–5 × 1.2–1.6 cm, oblong-loriform, dark purple-red, glabrous, apex round; stamens 6, filaments flat, ca. 0.9 cm long, dark purple-red, anthers ca. 1.4 cm long, falcate, connectives exceeding the anther sacs in measurements, anther sacs, ca. 0.9 cm, dark purple, pollen yellow; ovary obpyriform, green, ca. 0.9 cm, style ca. 2 mm long, green, densely speckled with red or purple, stigma multilobate (crown-shaped), dark purple-red. Berry globose, 1.5–2.4 cm long. Seeds numerous, lacking an aril.
This new species is currently known from Yueliang mountains of Congjiang County, Guizhou Province, Southwestern China. It grows under forests, at an elevation between 800 and 1500 m.
This new species has been observed flowering from April to June and fruiting from June to September.
The specific epithet is derived from the character (white-villous petioles, stems and abaxial leaf blade) of this species.
CHINA. Guizhou: Congjiang County, Guanghui Town, Baiji Village, alt. 823 m, 25.633N, 108.291E, 20 April 2016, Z.W. Wang & H.C. Xi WAZW16029 (KUN); Congjiang County, Guanghui Town, Changniu Village, alt. 936 m, 25.596N, 108.271E, 20 April 2016, Z.W. Wang & H.C. Xi WAZW16032 (CSH); Ronjiang County, Jihua Town, Baiwang Village, alt. 806 m, 25.657N, 108.269E, 18 May 2017, Z.W. Wang & H.C. Xi WAZW17024 (KUN).
Dysosma villosa shares certain characteristics with D. difformis in having alternate leaves, leaf blades not deeply divided and/or undivided, inflorescence attached near the base of leaf blade, and oblong-loriform petals. However, it can be promptly recognised by its inflorescences generally having more flowers, and densely white-villose stems, petioles and abaxial leaf blade. Particularly, its densely white-villose stems, petioles and abaxial leaf blade and dark purple-red stigma are significantly different from D. difformis, as well as other species of Dysosma. In addition, it is worth mentioning that there are still three uncertain species described under Podophyllum (P. glaucescens, P. hemsleyi, and P. trilobulum) that probably belong to Dysosma (
Morphological comparison of key characters amongst Dysosma villosa, D. difformis and the three insufficiently known species of Podophyllum.
Characters | D. villosa | D. difformis | P. glaucescens | P. hemsleyi | P. trilobulum |
---|---|---|---|---|---|
Plant height | 9–23 cm tall | 15–30 cm tall | up to 40 cm tall | up to 40 cm tall | 20–25(–40) cm tall |
Leaf blade | abaxially densely white-villous, adaxially glabrous; not deeply divided or undivided | glabrous; not deeply divided or undivided | glabrous; lower leaf 4-lobed; upper leaf with 4 obvious and 2 obscure lobes | glabrous; lobes spatulate-oblong, lobed to 4/5 of radius | glabrous; lobes trilobulate, lower leaf lobes 7, upper leaf lobes 5 |
Stem and Petiole | densely white-villous | glabrous | glabrous | glabrous | with fine short hairs |
Inflorescence | attached near base of blade, 5–13-flowered | attached near base of blade, 2–5-flowered | inserted on petiole of upper leaf ca. 2 cm below blade, 7-flowered | inserted on petiole ca. 2 cm below blade, 4-flowered | inserted at or above midpoint on petiole of upper leaf, 2–5-flowered |
Pedicel | 1.6–2.2 cm long, sparsely white-villous | 1–2 cm long, sparsely white-pubescent | 4–6 cm long, densely hairy | 3–4 cm long, glabrous | 2.2–2.5 cm long, brown pilose |
Petal | oblong-loriform, 4–5 × 1.2–1.6 cm | oblong-loriform, 4–5 × 0.8–1 cm | ovate-lanceolate, 10–12 × 5–6 mm | oblong-spatulate, 3–3.5 cm× 5–8 mm | ovate-lanceolate, 4–5 × 8–10 mm |
Pistil | ovary obpyriform, ca. 1.2 cm long, style ca. 2 mm long, stigma crown-shaped, dark purple-red | ovary obpyriform, ca. 0.9 cm long, style ca. 2 mm long, stigma crown-shaped, yellowish | ovary ovoid, ca. 5 mm long, style 2–3 mm long, stigma peltate, corrugated, coloration unknown | ovary globose to pyriform, 6–7 mm long, style 2–3 mm long, stigma globose, corrugated, coloration unknown | unknown |
1 | Leaves opposite, inflorescence emerging at the petiole base | 2 |
– | Leaves alternate, inflorescences emerging at or near the apex of the petiole | 4 |
2 | Lobes of leaf apically trifid; petals oblong, up to 6 cm long | D. delavayi |
– | Lobes of leaf apically undivided; petals obovate-elliptic, ca. 3 cm long | 3 |
3 | Leaf blade glabrous, palmately-lobed, lobes triangular-ovate | D. pleiantha |
– | Leaf blade pubescent on both surfaces, palmately parted, lobes cuneate-oblong | D. tsayuensis |
4 | Inflorescences emerging far from the leaf blade; petals obovate, 1.4–1.6 cm long | D. aurantiocaulis |
– | Inflorescences emerging near the leaf blade; petals oblong, lanceolate or obovate, 2.4–10 cm long | 5 |
5 | Leaf lobes apically trifid; petals elliptic-lanceolate | D. majoensis |
– | Leaf lobes apically undivided; petals spatulate-obovate or oblong-loriform | 6 |
6 | Leaves 4–9-lobed or deeply divided; petals spatulate-obovate; berries ca. 4 cm long, ellipsoid or ovoid | D. versipellis |
– | Leaves not deeply divided or undivided; petals oblong-loriform; berries 1.5–2.7 cm diam., globose | 7 |
7 | Stems, petioles and leaf blades glabrous; inflorescences 2–5-flowered; stigma yellow | D. difformis |
– | Stems, petioles and leaf blades white-villous; inflorescences 5–13-flowered; stigma dark purple-red | D. villosa |
The authors are very grateful to Zhikun Wu of Guizhou University of Traditional Chinese Medicine and Yi Yang of Kunming Institute of Botany, Chinese Academy of Sciences for their help in taxonomic guidance. This study was supported by the Regional Science Foundation Project of the National Natural Science Foundation of China (31760053), the Natural Science Foundation of Guizhou Department of Education (QianJiaoHe KY Zi [2018]089), the Foundation of Guizhou Administration of Traditional Chinese Medicine (QZYY–2018–097) and the Foundation of the First-class Construction Disciplines Sub Project in Guizhou Province (Science of Chinese materia medica; GNYL[2017]008 Hao–7).