Research Article |
Corresponding author: Huai-Zhen Tian ( thz0102@126.com ) Academic editor: João Farminhão
© 2022 Yi-Hua Tong, Mei Sun, Bing-Mou Wang, Huai-Zhen Tian.
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:
Tong Y-H, Sun M, Wang B-M, Tian H-Z (2022) Goodyera medogensis (Orchidaceae), a new species from Tibet, China. PhytoKeys 189: 141-154. https://doi.org/10.3897/phytokeys.189.77374
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A new species of Goodyera (Orchidaceae) from Tibet, China, G. medogensis, is described and illustrated here. Molecular phylogenetic results based on one nuclear (ITS) and two plastid markers (matK and trnL-F) support the recognition of G. medogensis as a new species in Goodyera subsection Reticulum. Morphologically, the novelty is most similar to G. biflora, G. vittata and especially to G. hemsleyana, but differs by the thick grid lines of the reticulations with a diffused margin on the adaxial surface of the leaf blades, the inflorescence with more flowers, the obliquely obovate-rhombic petals, the yellow or yellowish labellum without a lamella on the blade, and the shorter trichomes on the floral bracts, sepals and ovary. Finally, a key to the species of Goodyera subsect. Reticulum in China is also provided.
Cranichideae, Jewel orchid, morphology, new species, Orchidoideae, phylogeny
The genus Goodyera R. Br. (Orchidaceae) belongs to the subtribe Goodyerinae (
Goodyera s.l. consists of about 99 species distributed in Africa (Mozambique), Western Indian Ocean Islands, Asia, Southwest Pacific islands, Northeast Australia, Europe, Macaronesia (Madeira), North and Central America and the Caribbean (
There are 36 accepted species of Goodyera in China, of which 15 species are endemic (
Based on molecular phylogenetic evidence and a detailed examination of the morphological characters of our materials, the relevant types and a comprehensive array of additional herbarium specimens of similar species, we concluded that the plants discovered in Medog County in January 2021 represented a new species to science. It is described and illustrated here as G. medogensis H. Z. Tian, Y. H. Tong & B. M. Wang and included in a key to the species of Goodyera subsect. Reticulum in China.
Based on our field observations of Goodyera in China in the past ten years, we identified three species that were closely related to the novelty, viz. G. hemleyana, G. biflora (Lindl.) Hook. f. and G. vittata Benth. ex Hook. f. (Fig.
Voucher specimens of G. medogensis were collected in Medog County and preserved at the herbarium of South China Botanical Garden, Chinese Academy of Sciences (
To study the phylogenetic position of the new species within the genus Goodyera, three DNA fragments, viz. internal transcribed spacer (ITS) and two plastid DNA regions (matK and trnL-F), were selected for building the phylogenetic tree based on previous studies (
Total genomic DNA of the new species was extracted from silica gel-dried leaves using a modified CTAB method (
Sequences were firstly assembled and edited with Seqman (DNA STAR package, Madison, WI, F USA) and then adjusted manually. Phylogenetic analysis was conducted using PhyloSuite ver. 1.2.2 (
Based on these models, the Maximum Likelihood (ML) analysis was performed with IQ-TREE (
Our ML and BI phylogenetic trees constructed from the three datasets showed that our four samples of G. medogensis cluster into one separate subclade (Figs
Phylogenetic tree of Goodyera species inferred by Bayesian and maximum likelihood analyses based on the nrDNA (ITS) dataset. Posterior probability (PP) ≥ 0.50 in BI analysis and bootstrap (BS) % values ≥ 50 in ML analysis are indicated above the branches. Dashes mean the nodes are not supported, i.e. the BS value < 50% in the ML analysis or PP < 0.50 in the BI analysis. The samples of the new species are highlighted in orange, and other species of sect. Reticulum are highlighted in bold. The clade of Goodyera sect. Reticulum is highlighted with the green rectangle.
Phylogenetic tree of Goodyera species inferred by Bayesian and maximum likelihood analyses based on the cpDNA (matK + trnL-F) datasets. Posterior probability (PP) ≥ 0.50 in BI analysis and bootstrap (BS) % values ≥ 50 in ML analysis are indicated above the branches respectively. Dashes mean the nodes are not supported, i.e. the BS value < 50% in the ML analysis or PP < 0.50 in the BI analysis. The samples of the new species are highlighted in orange, and other species of sect. Reticulum are highlighted in bold. The clade of Goodyera sect. Reticulum is highlighted with the green rectangle.
Phylogenetic tree of Goodyera species inferred by Bayesian and maximum likelihood analyses based on the nr + cpDNA (including ITS, matK and trnL-F) datasets. Posterior probability (PP) ≥ 0.50 in BI analysis and bootstrap (BS) % values ≥ 50 in ML analysis are indicated above the branches respectively. Dashes mean the nodes are not supported, i.e. the BS value < 50% in the ML analysis or PP < 0.50 in the BI analysis. The samples of the new species are highlighted in red, and other species of sect. Reticulum are highlighted in bold. The clade of Goodyera sect. Reticulum is highlighted with the green rectangle.
China. Tibet Autonomous Region: Medog County, Renqingbeng Temple, under evergreen broad-leaved forest, cultivated at Kunming Botanical Garden, 3 August 2021 (fl.), B. M. Wang TYH-2523 (holotype:
Similar to G. hemsleyana, but distinguished by the greenish thick reticulations on the adaxial surface of leaf blades with diffused margin (vs. white thin reticulations with clear margin), inflorescence with more flowers ((6–)12–15 vs. 4–10), petals obliquely obovate-rhombic (vs. obliquely ovate-oblong), labellum yellow or yellowish (vs. white, with light greenish to pinkish tinge at apex) without lamella on blade (vs. with a low bi-lamellate callus), and floral bracts, sepals as well as ovary with shorter trichomes.
Goodyera medogensis A habit B inflorescence C flower, lateral (left) and front (right) view, with the arrow showing close-up of trichomes on abaxial surface of sepals D sepals E petals F column with labellum, anther and ovary G labellum H pollinarium I column with part of the ovary. Photographs by Yi-Hua Tong.
Terrestrial herb, 12–25 cm tall. Rhizome 4–6 cm long, 1.5–3 mm in diam., greenish, rooting at nodes. Roots fleshy, 0.7–7 cm long, yellowish brown, with minute root hairs. Stem erect, terete, 4–9 cm long, 2.7–4 mm in diam., pale green, glabrous, with few sheaths at base formed by withered bases of petioles. Leaves 3–7; petiole 1.1–1.6 cm long, sheathing at base; lamina ovate, 1.9–4.2 × 1.5–2.6 cm, obtuse at base, acute at apex, adaxially green to bluish green with greenish-white reticulations, grid lines thick, margin diffused, transverse ones 5–7, abaxially pale green, 5–7-veined. Inflorescence a terminal raceme, laxly (6–)12–15-flowered, spirally arranged, pubescent; peduncle 4–6.5 cm long, pubescent, with 2–3 sheathing bracts; sheathing bracts 1.5–1.9 × 0.6–0.8 cm, oblong-lanceolate, acute at apex, pale green, clasping, more or less pubescent, especially on the margin, 3–5-veined; rachis 3.5–7 cm long, pubescent. Floral bracts ovate-lanceolate, 1.4–1.7 × 0.5–0.6 cm, acuminate to acute at apex, pale green, longer than ovary, sometimes shortly ciliate at margins, pubescent abaxially, trichomes multicellular, up to 0.8 mm long, glabrous adaxially, 3-veined. Flowers resupinate, opening weakly, 8–10 mm long. Sepals 1-veined, acute at apex, olive greenish, with reddish or brownish tinge when old, with dense clavate trichomes outside, trichomes up to 0.5 mm long; dorsal sepal ovate-lanceolate, 8–9 × 2–3 mm, forming a hood with the petals; lateral sepals ovate-lanceolate, 8–9 × 3.5–4 mm. Petals obliquely obovate-rhombic, 8–8.5 × 3–3.5 mm, acuminate to acute at apex, white, with reddish or brownish tinge at central part, glabrous, 1-veined. Labellum oblong-ovate, 6–7 mm long, yellow or yellowish; hypochile with a sac ca. 1.5–2.5 × 2.5–3.5 mm, with glandular hairs inside; epichile oblong to oblong-lanceolate, entire, 5–6.5 × 2–3 mm, margins slightly undulate, obtuse to subacute at apex. Column cylindrical, ca. 1 mm long; rostellum 3.5–4 mm long, bifid, acuminate at apex. Stigma suborbicular, ca. 1 × 1 mm, entire. Anther yellowish brown, ovate, ca. 2.5 × 1.5 mm. Pollinarium 3–3.5 mm long; pollinia 2, oblong-obclavate, 0.8–1 mm long, dull yellowish white, sectile, bifid; caudicles 1.5–1.7 mm long; viscidium narrowly ovate-oblong, 2–3× ca. 0.5 mm, acute at apex, membranous. Ovary plus pedicel terete, 6–7.5× ca. 2 mm, pale green, twisted, pubescent, trichomes blunt, multicellular, consisting of 5–7 cells. Fruit not seen.
The species epithet refers to the type locality, Medog County.
墨脱斑叶兰 (Chinese pinyin: mò tuō bān yè lán).
This species is currently known only from Medog County, Tibet, China. It grows under evergreen broad-leaved forests at elevations of 1600–2300 m.
During our three surveys in January, June and August 2021, Goodyera medogensis was found in the forests of Medog Town and Beibeng Township of Medog County, where we counted a minimum of 200 individuals. However, since the population assessment of this species in the whole Medog County has not been made, conservation status of this new species is best classified as ‘Data Deficient’ (DD) (
Flowering in July-August.
Goodyera medogensis (paratypes): China: Tibet Autonomous Region, Medog County, Bari village, elev. 1750 m, 23 June 2021, cultivated in East China Normal University, 10 August 2021 (fl.), J. Huang & M. Sun 21062310 (
Goodyera hemsleyana: India: Senchal, 2100 m, July 1892, Pantling 215 (lectoype: CAL0000000625 (photo); isolectotypes: CAL0000000624 (photo), K00387611, BR0000006573508 (photo), M0226196 (photo), AMES00090573 (photo), P00333538 (photo)).
Goodyera biflora: Nepal: sin. loc., Wallich, Cat. no. 7379 (holotype: K000364600; isotype: K001127259). India: sin. loc., 1900, J. F. Duthie 24164 (K); Mussorie, July 1901, P. W. Mackinnon 25408 (AMES02091486, photo); Himachal Pradesh, Shimla, 1524 m, 30 June 1886, H. Collett. 325 (K); Himalaya, 1981 m, 1844, M. P. Edgeworth 58 (K). China: Tibet, Gyirong Valley, Tsangpo Valley, 2743 m, 6 August 1935, F. Kingdom-Ward 12159 (K); Tibet, Bome, 2 July 1952, P. C. Tsoong 6699 (PE00339319, PE00339320); Anhui, Jinzhai, 1600 m, 6 August 1986, Plant Resource Team D0062 (PE); Guangdong, Fengkai, 16 June 1974, Yue Seven Four 5295 (IBSC0627265); Guangdong, Xinyi, 15 April 1931, S. P. Ko 51307 (IBSC0627264, IBSC0627266, IBSC0627267, PE00339323, PE00339324); Guangdong, Ruyuan, 27 November 1957, L. Teng 5866 (IBSC0627260); Guizhou, Fanjing Mt., 10 September 1987, China-USA Scientific Research Team s.n. (PE00339322); Guizhou, Rongjiang, 10 July 1974, Anonymous 74-913 (IBSC0627261); Henan, Xin County, 10 August 2013, C. S. Zhu, S. J. Li, X. L. Hou, S. X. Zhu, J. M. Li 130808106 (AU066898, photo); Henan, Shangcheng, 19 June 1984, Plant Resource Research Team D0546 (PE00850731); Hubei, Huanggang, 2 October 2018, X. X. Zhu, L. L. Shi, S. S. Duan, M. J. Hu, Q. Lü ZXX18494 (KUN1444572, photo); Hubei, Shiyan, 8 July 2013, S. L. Li GanQL486 (KUN1458343, photo); Hunan, Chengbu, 22 May 2020, L. Wu, W. J. Liu, C. F. Deng 10403 (CSFI071975, photo); Hunan, Sangzhi, 600 m, 22 June 1991, Q. Lin 714 (IBSC0627263); Hunan, Sangzhi, 11 June 2019, X. Li, C. F. Deng, J. L. Li 190611132 (CSFI072175, photo); Hunan, Cili, 2 October 1984, G. X. Xing & Q. Xia 05571 (PE00339318); Sichuan, Hechuan to Mabian, 1934, S. L. Sun 5590 (PE00339322); Sichuan, s. d., P. C. Tsoong 3981 (PE01849749); Yunnan, Wenshan, 25 September 1958, H. T. Tsai 58-8126 (KUN0022202); Zhejiang, West Tianmu, 2 July 1925, D. X. Zhang 266 (LBG00108146).
Goodyera vittata: India: Sikkim Himalaya, J. D. Hooker 336 (holotype: K000364605); Singalelah Range, 2438 m, July 1896, R. Pantling 410 (AMES02091540, photo). China: Tibet, Zayu, 25 July 1980, 2100 m, Z. C. Ni, Y. Z. Wang, D. Ci et al. 0757B (PE00339514); Yunnan, Yingjiang, 14 August 2012, H. Z. Tian & C. Hu 706 (
1 | Inflorescence with more than 20 flowers; dorsal sepal less than 6 mm long | 2 |
– | Inflorescence with less than 20 flowers; dorsal sepal more than 6 mm long | 6 |
2 | Leaves green, without white or pale green venation on adaxial surface | G. yamiana |
– | Leaves with white or pale green venation on adaxial surface | 3 |
3 | Margins of epichile and petals irregularly denticulate | G. pusilla |
– | Margins of labellum and petals entire | 4 |
4 | Flowers glabrous | G. hachijoensis |
– | Flowers pubescent | 5 |
5 | Flower diameter 6–7 mm | G. malipoensis |
– | Flower diameter 3–4 mm | G. hispida |
6 | Inflorescence mostly with 2 flowers, sometimes up to 6; dorsal sepal 20–25 mm long | G. biflora |
– | Inflorescence mostly with 4–15 flowers; dorsal sepal 3–14 mm long | 7 |
7 | Leaves adaxially with a white band along midvein | G. vittata |
– | Leaves adaxially with white or greenish reticulate venation | 8 |
8 | Leaves adaxially with thin and white reticulations with clear margins; labellum white, with light greenish to pinkish tinge at apex | G. hemsleyana |
– | Leaves adaxially with thick and greenish reticulations with diffused margins; labellum yellow or yellowish | G. medogensis |
The new species has the typical features of Goodyera sect. Reticulum, i.e., the leaves have reticulations on adaxial surface, and lateral sepals are not reflexed backwards. According to
We are grateful to Mr. Zhen Liu (Medog Forestry Bureau) and Mr. Xi-Xian Wang (China Railway 12th Bureau Group) for their help during field trips. Mr. Jun Cai is thanked for preparing the beautiful line-drawing. We also thank the curators and staff of the herbaria mentioned above for facilitating the checking of specimens and Dr. Pankaj Kumar (Kadoorie Farm & Botanic Garden) for his valuable comments. This study was funded by the National Natural Science Foundation of China (grant no. 31870180), Biological Resources Program, Chinese Academy of Sciences (KFJ-BRP-017-33) and Biodiversity Survey, Observation and Assessment Program of Ministry of Ecology and Environment of China.
Table S1, S2. Supplementary file of Goodyera medogensis (Orchidaceae), a new species from Tibet, China
Data type: phylogenetic
Explanation note: Details of materials for phylogenetic study and primers for sequence amplication and sequencing.