Research Article |
Corresponding author: Yun Lin ( leoliny@foxmail.com ) Academic editor: Petra De Block
© 2019 Lin-Dong Duan, Yun Lin, Zhen Lu.
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:
Duan L-D, Lin Y, Lu Z (2019) Ophiorrhiza shiqianensis (Rubiaceae), a new species from Guizhou, China. PhytoKeys 121: 43-51. https://doi.org/10.3897/phytokeys.121.30570
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A new species of the genus Ophiorrhiza L. (Rubiaceae), Ophiorrhiza shiqianensis L.D.Duan & Yun Lin, is described, illustrated and photographed from Shiqian County, Guizhou Province, South-western China. This species was found growing at the side of streams in evergreen broad-leaved forests in mountains at elevations of 960–1100 m. The new species is morphologically similar to Ophiorrhiza hunanica H.S.Lo, but differs from the latter by the glabrous, glabrescent or pilose stems, the 5–10 cm long subterranean stem internodes, the glabrous or pilose petioles, the 3–5 mm long stipules, the purple corolla lobes, the ca. 12 mm long style and included stigmas in long-styled flowers and the 3–4 × 8–10 mm, glabrous or glabrescent capsules.
Distyly, morphology, new taxon, taxonomy
The Rubiaceae genus Ophiorrhiza L. includes more than 300 species worldwide (
During three botanical explorations in Shiqian County, Guizhou Province, Southwest China, specimens of Ophiorrhiza were collected on the banks of streams in dense evergreen broad-leaved forests in valleys at elevations of 960–1100 m. After comparison of the newly collected specimens with material available in Chinese herbaria and careful consultation of literature, they were found to be most similar to Ophiorrhiza hunanica H.S.Lo, but sufficiently different to qualify as a new species, hitherto not reported from any region in China. We therefore describe it as new, under the name Ophiorrhiza shiqianensis L. D. Duan & Yun Lin.
Three field expeditions were carried out in Shiqian County, Guizhou Province, Southwest China in August 2011 and in March and May 2014 and a total of 30 mature individuals from the type locality (latitude 27°19'01.33"N, longitude 108°00'25.76"–108°00'35.76"E) were collected. All morphological measurements were performed on dried and fresh specimens. For the identification of specimens, relevant literature was used (
Similar to Ophiorrhiza hunanica H. S. Lo based on stems, leaves and capsules; differing from it by the stems which are glabrous, glabrescent or pilose, the 5–10 cm long subterranean stem internodes, the glabrous or pilose petioles, the 3–5 mm long stipules, the purple corolla tube and lobes, the ca. 12 mm long styles and the included stigmas in long-styled flowers, the 3–4 mm × 8–10 mm, glabrous or glabrescent capsules [vs. stems densely villose, subterranean stem internodes 1–2 cm long, petioles villose, stipules 5–15 mm long, corolla tube purple and corolla lobes white, style 15–17 mm long and stigmas exserted in long-styled flowers, capsules 5–6 mm × 10–12 mm, densely villose in Ophiorrhiza hunanica (Figs
Ophiorrhiza shiqianensis. A habit of flowering plant B section of stem, showing stipules C inflorescence D flower E long-styled flower F pistil in a long-styled flower G short-styled flower H capsule A–F from L.D. Duan, Z. Lu & Q. Lin 5805 G from L.D. Duan, Z. Lu & Q. Lin 5808 H from L.D. Duan, Z. Lu & Q. Lin 5809.
CHINA. Guizhou: Shiqian County, Pingshan Town, Fudingshan Nature Reserve, at sides of streams in dense evergreen broad-leaved forest in valley at 960 m elevation, 18 March 2014 (fl), L.D. Duan, Z. Lu & Q. Lin 5805 (holotype: PE!, Herb. Bar. Code No. 02232812; isotypes HUFD! (=Herbarium, Hunan Food and Drug Vocational College, Hunan, China), HUSY! (=Herbarium, Shaoyang University, Hunan, China) IBSC!, K!, KUN!, PE!).
Perennial herbs, 10–30 cm tall, repent at base. Stems erect, fleshy, green, brown to black after drying, glabrous, glabrescent or pilose; subterranean stems glabrous with 5–10 cm long internodes. Leaves: petioles 1.5–4.0 cm long, glabrous or pilose; blades papery after drying, elliptic or obovate-elliptic, 7–17 cm × 3–7.5 cm, adaxially pilose, abaxially pilose on veins, base cuneate, apex obtuse to subacute; secondary veins 9–11 pairs; stipules often persistent, ovate to ovate-lanceolate, 3–5 mm long, ciliate. Inflorescence cymose, terminal, 2- to 10-flowered, densely villose, pendulous; peduncle 2.5–4 cm long when flowering, 8–10 cm long when fruiting, arching, densely villose. Bracts linear-lanceolate, 9–10 mm long, ciliate; bracteoles linear, 4–5 mm long, ciliate. Flowers distylous, pedicels 1–2 mm long, densely covered with hairs. Calyx with hypanthium compressed-turbinate, 2.5–3 mm long, 5-ribbed, densely covered with hairs; lobes 5, lanceolate-linear, 5–6 mm long, ciliate. Corolla tube and lobes purple, funnel-form, outside glabrous, inside pubescent; tube 1.7–1.8 cm long; lobes 5, ovate-triangular, 4–6 mm long, apex rostrate. Stamens 5, inserted near throat and exserted at anthesis in short-styled flowers or inserted below middle of corolla tube and included at anthesis in long-styled flowers; filaments 1.5–2 mm long in short-styled or ca. 1 mm long in long-styled flowers; anthers ca. 2.5 mm long, dorsifixed. Ovary 2-celled, ovules numerous in each cell; style ca. 12 mm long in long-styled or 7–7.5 mm long in short-styled flowers; stigmas 2, linear in short-styled or subcapitate in long-styled flowers, included in both morphs. Capsules purple, mitriform, strongly laterally compressed, 3–4 mm × 8–10 mm, pilose or glabrescent. Seeds numerous.
Plants were observed in full bloom on 18 March 2014 and with ripe fruits on 12 May 2014 and neither flowers nor fruits were seen on 12 August 2011. It can be expected that the flowering time of the new species is from March to April and that fruiting time is from April to June.
The species grows on the banks of streams in dense broad-leaved forest in valleys at elevations of 960–1100 m.
Ophiorrhiza shiqianensis is only known from two localities in Shiqian County, northeast Guizhou Province, southwest China, notably: Fudingshan Nature Reserve, Pingshan Town and Nishan Village, Ganxi Town.
Ophiorrhiza shiqianensis is named after its type locality, Shiqian County, northeast Guizhou Province, southwest China.
Shi qian she gen cao in Chinese Pinyin.
Ophiorrhiza shiqianensis is only known from four collections in two locations, Fudingshan Nature Reserve (well protected, 152 km2) and Nishan Village (ca. 50 km2). It comprises about 200 individuals (criteria D1 ≤ 250) growing in ten populations. This new species can be assessed as Endangered (EN) according to the IUCN Red List Categories and Criteria (
CHINA. Guizhou: Shiqian County, Ganxi Town, Nishan Village, Niujinshan, stream-sides in dense evergreen broad-leaved forest in valley at 1100 m elevation, 12 August 2011 (sterile), L. D. Duan, Z. Lu & Q. Lin 5356 (HUFD!, HUSY!, PE!); Pingshan Town, Fudingshan Nature Reserve, stream-sides in dense evergreen broad-leaved forest in valley at 960 m elevation, 18 March 2014 (fl), L. D. Duan, Z. Lu & Q. Lin 5808 (HUFD!, HUSY!, PE!); same locality, 12 May 2014 (fr), L. D. Duan, Z. Lu & Q. Lin 5809 (HUFD!, HUSY!, IBSC!, K!, KUN!, PE!).
The new species most resembles Ophiorrhiza hunanica. Detailed morphological differences between the two species are given in Table
Comparison of morphological characteristics between Ophiorrhiza shiqianensis and O. hunanica.
Characters | O. shiqianensis | O. hunanica |
---|---|---|
Plant | repent at base | procumbent or repent at base |
Stem | glabrous, glabrescent or pilose; subterranean stem internodes 5–10 cm long | villose; subterranean stem internodes 1–2 cm long |
Leaf | petiole 1.5–4.0 cm long, glabrous or pilose; blade 7–17 cm long; stipules 3–5 mm long | petiole 1–6 cm long, villose; blade 7–23 cm long; stipules 5–15 mm long |
Flower | 2- to 10-flowered; peduncle 2.5–4 cm long when flowering, 8–10 cm long when fruiting; corolla tube and lobes purple; style c. 12 mm long and stigmas included in long-styled flowers | 5- to many-flowered; peduncle 3–8 cm long when flowering, 12–15 cm long when fruiting; corolla tube purple and lobes white; style 15–17 mm long and stigmas exserted in long-styled flowers |
Capsule | 3–4 mm × 8–10 mm, glabrous or glabrescent | 5–6 mm × 10–12 mm, densely villose |
Thanks are due to the curators of the following herbaria CDBI, CSFI, GXMI, GZAC, GZTM, HGAS, HIB, HNNU, IBK, IBSC, IMC, KUN, LBG, NAS, PE, SZ and SYS for the loan of specimens or for permission to examine specimens. We sincerely thank three reviewers for the English revision and their valuable comments on our manuscript. This work was supported by the project of the Education Department in Hunan Province (grant number 16A194) and supported by the National Specimen Information Infrastructure (grant numbers 2005DKA21400 and 2005DKA21401).