A new species, Lysimachia huangsangensis (Primulaceae), from Hunan, China is described and illustrated. The new species is closely related to L. carinata because of the crested calyx, but differs in the leaf blades that are ovate to elliptic and (3–)4.5–9 × 2–3.4 cm, 2–5-flowered racemes, and the calyx lobes that are ovate-lanceolate and 5–6 × 3–4 mm. The systematic placement and conservation status are also discussed.
Citation: Zhou J-J, Yu X-L, Deng Y-F, Yan H-F, Lin Z-L (2015) Lysimachia huangsangensis (Primulaceae), a New Species from Hunan, China. PLoS ONE 10(7): e0132713. https://doi.org/10.1371/journal.pone.0132713
Editor: Nico Cellinese, University of Florida, UNITED STATES
Received: February 19, 2015; Accepted: June 15, 2015; Published: July 22, 2015
Copyright: © 2015 Zhou et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Data Availability: All relevant data are within the paper and its Supporting Information files.
Funding: This study was supported by the major special foundation of Science and Technology Department of Hunan Province (Gran no. 2012FJ1005, www.hnst.gov.cn) and special program of scientific investigation from the Huangsang National Natural Reserve (grant no. N/A) to Xun-Lin Yu, and the National Natural Science Foundation of China (grant no. 30900160, 31270247, 31470302, www.nsfc.gov.cn) to Hai-Fei Yan and Yun-Fei Deng. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Competing interests: The authors have declared that no competing interests exist.
Lysimachia L. belongs to the tribe Lysimachieae Reich. and consists of 140–200 species with an almost worldwide distribution but exhibits striking local endemism [1–7]. China is one of the centers of diversity for Lysimachia, being home to approximately 140 species [5, 8–20].
Traditionally Lysimachia was recognized as a primitive group in the family Primulaceae and to be related to the family Myrsinaceae [21–28]. Molecular phylogenetic studies as well as morphological data have supported the transfer of Lysimachia with other genera of the tribe Lysimachieae to the family Myrsinaceae [4, 29–34]. However, in the recent system of the Angiosperm Phylogeny Group [35–37], Mysinaceae is merged with Primulaceae and the Primulaceae are divided into four subfamilies: Maesoideae, Theophrastoideae, Myrsinoideae, and Primuloideae .
Many taxonomists have tried to establish an infrageneric classification for the genus. Klatt  was the first to subdivide the genus and recognized nine sections. Pax & Knuth went on to divide the genus into 16 sections. Handel-Mazzetti  established a new arrangement for the genus and divided it into five subgenera, viz., subgen. Lysimachia, subgen. Idiophyton Hand.-Mazz., subgen. Naumburgia (Moench) Hand.-Mazz., subgen. Lysimachiopsis (Heller) Hand.-Mazz. and subgen. Pallidia (Moench) Hand.-Mazz. His system constitutes the most important contribution to the classification of Lysimachia and was followed by many authors with minor modifications [8, 9, 24, 34, 40]. Ray  separated species of the New World into five subgenera. Chen & Hu [8, 9] divided Chinese Lysimachia into five subgenera adding subgen. Heterostylandra (Hand.-Mazz.) F.H. Chen &C.M. Hu and subgen. Lysimachiopsis, which does not occur in China.
Recent phylogenetic analyses [32, 34, 41–44] found that the genus Lysimachia in the traditional sense was paraphyletic, and some related satellite genera, viz., Anagallis L., Asterolinon Hoffmans. et Link, Glaux L. and Pelletiera A. St.-Hil., were nested within Lysimachia. Accordingly, Lysimachia was expanded to include these satellite genera to maintain Lysimachia as a monophyletic entity [45, 46]. The traditional subgeneric classification was re-evaluated by Anderberg et al..
In the course of field work in SW Hunan Province, China, a distinct species of Lysimachia with a crested calyx was found. Further studies showed that it represented a new species belonging to ser. Drymarifoliae Hand.-Mazz. in subgen. Lysimachia sensu Chen & Hu . Ser. Drymarifoliae includes about 10 species in China and is characterized by having the flowers arranged in umbel-like, axillary, 1–several-flowered racemes and filaments connate at the base . In this series, the species can be divided into two groups according to whether the calyx has crested ridges or not. The new species belongs to the group having a crested calyx.
Material and Methods
The new species reported in this work was collected from Huangsang Natural Reserve and Yunshan Natural Reserve, Hunan, China, which are protected by the Forestry Bureau of Hunan Province. The Forestry Bureau permits research in these reserves and no specific permits are required for the present study. The field studies did not involve endangered or protected species.
The morphological description of the new species was based on the examination of fresh and pressed specimens. The morphological comparison with related species, L. carinata Y. I. Fang & C. Z. Zheng, L. pterantha Hemsl., L. baoxingensis (F. H. Chen &C. M. Hu) C. M. Hu, L. pteranthoides Bonati and L. crista-galli Pamp. ex Hand.-Mazz., was based on studies of herbarium specimens and information gathered from literature searches. The specimens examined were deposited in the following herbaria: CDBI, IBSC, K, NAS, P, PE and WUK. The herbarium acronyms follow the Index Herbariorum .
The pollen grains and seeds were directly mounted on aluminium stubs coated with gold in a sputter coater and examined using scanning electron microcopy (SEM). The polar (P) axis and equatorial (E) diameter were measured by imaging analyzer (Smile View 2.1; JEOL Tokyo, Japan). Pollen terminology follows Erdtman  and Bennell & Hu . Seed terminology follows Oh et al..
The electronic version of this article in Portable Document Format (PDF) in a work with an ISSN or ISBN will represent a published work according to the International Code of Nomenclature for algae, fungi, and plants, and hence the new names contained in the electronic publication of a PLOS article are effectively published under that Code from the electronic edition alone, so there is no longer any need to provide printed copies.
In addition, new names contained in this work have been submitted to IPNI, from where they will be made available to the Global Names Index. The IPNI LSIDs can be resolved and the associated information viewed through any standard web browser by appending the LSID contained in this publication to the prefix http://ipni.org/. The online version of this work is archived and available from the following digital repositories: PubMed Central and LOCKSS.
In order to determine the systematic position of the new species, we proceeded to create a phylogenetic analysis by adding published sequences of Chinese Lysimachia species. We retrieved a total of 66 sequences for 25 species downloading those published in a barcoding study of Chinese Lysimachia  from GenBank, In addition, three samples representing the new species were included in this study.
Total genomic DNA was extracted from silica-dried plant leaves using a modified CTAB protocol , and then target DNA regions including the two core barcodes (rbcL and matK), trnH-psbA and ITS were amplified with common DNA barcoding primers. Primer pairs, PCR amplification and sequencing conditions following Zhang et al.  and Chen et al. . GenBank accession numbers for all the DNA sequences and voucher information are given in S1 Table.
Sequence alignment and phylogenetic analysis
Sequence alignment was initially performed using with MUSCLE 3.8.31  in the multiple alignment routine followed by manual adjustment in Se-Al v2.0a11 (http://tree.bio.ed.ac.uk/software/seal/). Given that the plastid genome behaves as a single linked region, the three plastid markers (rbcL, matK and trnH-psbA) were concatenated a priori. Congruence between the combined plastid fragments and nuclear marker ITS was tested with the incongruence length difference (ILD) test , which was conducted using PAUP* version 4.0b10with 100 replicates of the heuristic search (default setting) . The 1% level of significance was chosen as described in . The ILD value in this study was 0.02 and we therefore,decide to combined all the datasets (rbcL, matK,psbA-trnH, and ITS) in our analysis using Maximum Likelihood (ML) analysis. We first determined the best-fitting model of sequence evolution for the total data matrix using ModelTest 3.7 . Results of the Akaike information criterion (AIC, ) indicated that the TIM + I + G model was the best-fitting model for the combined data matrix. The ML analysis was performed using GARLI Web Service [57, 58] with the best-fitting model (http://www.molecularevolution.org/software/phylogenetics/garli). Default parameters were used in this analysis, and 10 independent search replicates were run with each replicate run. Bootstrap support values for nodes on the ML topology were computed with GARLI by running 500 bootstrap replicates.
Bayesian inference (BI) was conducted using MrBayes version 3.2.1  with the best-fitting model (TIM + I + G). The Bayesian Markov chain Monte Carlo (MCMC) algorithm was run for 5000000 generations with four incrementally heated chains starting from random trees and sampling one out of every 1000 generations. A conservative burn-in (25%) was applied after checking for stability on the log-likelihood curves and split variances less than 0.01. A majority rule consensus tree was calculated from the remaining trees. The internodes support was determined by Bayesian Posterior Probabilities.
[urn:lsid:ipni.org:names:77147698–1] J.J. Zhou, X.L. Yu & Y.F. Deng, sp. nov. (Figs 1 and 2). Type: China. Hunan: Suiningxian, Huangsang Natural Reserve, Anyangshan Cun, ca. 480 m, 20 May 2013, J. J. Zhou &D. Zhou 13338 (holotype CSFI; isotype IBSC).
A. Habit; B. Fruiting branch; C. Calyx; D. Calyx-lobe showing crest ridge; E. Open corolla with stamens; F. Ovary and style; G. Fruit; H. seed. Drawn by Jing TIAN. (A-F from J. J. Zhou & D. Zhou 13338, G from J. J. Zhou 14101902).
A. Flowering branch; B. Fruiting branch; C. Calyx and pistile; D. Flower; E. Equatorial view of pollen grain; F. Polar view of pollen grain; G. Seed; H. Ornamentation of seed surface. IL inner layer of the seed coat; OL outer layer of the seed coat.
The new species is similar to Lysimachia carinata Y.I. Fang & C.Z. Zheng, but differs in ovate to elliptic and (3–)4.5–9 × 2–3.4 cm (versus broadly ovate to ovate and 1.5–2.5 × 1–2 cm), the 2–5-flowered racemes (versus 1–2-flowered) and the calyx lobes that are ovate-lanceolate and 5–6 ×3–4 mm (versus linear-lanceolate and ca. 4 × 1 mm).
Perennial herbs, to 40 cm tall. Stems purplish-red, procumbent at base, then erect, simple or rarely branched from base, glabrous. Leaves opposite; petioles 0.5–2 cm, purplish-red, glabrous, narrowly winged toward the base; blades ovate to elliptic, (3–)4.5–9 × 2–3.4 cm, abaxially glabrous, adaxially sparsely bristly, base rounded to narrowly cuneate, decurrent onto the petiole, margin entire to slightly undulate, apex acute to acuminate, midvein purplish, slightly impressed adaxially, prominent abaxially, lateral veins 6–8 pairs, flat adaxially, prominent abaxially, tertiary veins inconspicuous. Raceme axillary, 2–5-flowered; peduncle and rachis short, 1–3 mm long; pedicel slender, purplish-red, 1.5–3.5 cm long, glabrous. Calyx 5-lobed to the base, lobes ovate, 5–6 × 3–4mm, glabrous, abaxially crested, base rounded, margin entire, apex acute; crest 1–2.5 mm, wing-like, widest at the base, glabrous. Corolla 1–1.2 cm, yellow, glabrous, tube 5–6 mm, lobes ovate to elliptic, 5–7 × 4–5 mm, apex acute, margin entire. Stamens 5, yellow, 6–8 mm long, base connate into a tube for 1/3–1/2; anthers yellow, oblong, ca. 1.5 mm, dorsifixed, opening by lateral splits; pollen grains medium-sized, subprolate, 29.39 (26.3–34.3) ×25.31 (23.2–27.1) μm, tricolporate, P/E = 1.36, and tectum reticulate. Ovary ovoid, ca. 1.5 mm, glabrous; styles slightly longer than the stamens, glabrous. Capsule subspherical, ca. 5 mm in diameter, glabrous. Seeds polyhedral with lateral faces slandered towards the ventral face, black, ca. 1 mm, surface reticulate.
Distribution and habitat
Lysimachia huangsangensisis known from SW Hunan Province, China (Fig 3). It grows in scrubs or by the side of evergreen-deciduous and mixed-evergreen forest trails in association with Acer davidii Franch., Bretschneidera sinensis Hemsl., Carpinus viminea Lindl., Cyclobalanopsis glauca (Thunb.) Oerst., C. sessilifolia (Blume) Schottky, Emmenopterys henryi Oliv., Camellia pitardii Sohen-Stuart, Maesa japonica (Thunb.) Moritzi ex Zoll., Symplocos ramosissima Wall. ex G. Don, Asarum caudigerum Hance, Carex cruciata Wahl., Impatiens hunanensis Y.L. Chen, Justicia quadrifaria (Nees) T. Anderson, Lysimachia congestiflora Hemsl., Miscanthus sinensis Andersson and Oplismenus undulatifolius var. japonicas (Steud.) Koidz.
The epithet “huangsangensis” is derived from the type locality, Huangsang Natural Reserve, Suining Xian, Hunan Province, China.
Additional specimens examined (Paratypes)
CHINA. Hunan: Wugang, Yunshan, ca. 950 m, 2 June 2014, J. J. Zhou 140602001 (CSFI); the same locality, 19 October 2014, J. J. Zhou 14101902 (CSFI, IBSC).
Lysimachia huangsangensis has only been collected in 2014 from two protected areas in southwest Hunan, China. However, it is not excluded that this species could be found in other localities and therefore it is classified as Data Deficient (DD)  according to the guidelines for using the IUCN Red List Criteria .
According to the classification of Chen and Hu [8, 9], the new species belongs morphologically to Ser. Drymarifoliae Hand.-Mazz. . Ser. Drymarifoliae can be divided into two groups based on calyx characters. The new species belongs to a group having crested calyx lobes together with L. carinata, L. pterantha, L. baoxingensis, L. pteranthoides and L. crista-galli (specimens examined are listed in S1 Text). Lysimachia huangsangensis is most similar to L. carinata and differs in the character of leaf blades, inflorescence and calyx-lobes. The new species can be distinguished from allied species by the following key.
1a. Leaf base cordate; crest of calyx lobes widest above middle.
2a. Leaves densely minutely bristly, crest of calyx lobes not forming a spur...... L. pteranthoides.
2b. Leaves strigillose or glabrescent, crest of calyx lobes forming a spur...................... L. crista-galli.
1b. Leaf base narrowly cuneate to rounded or truncate; crest of calyx lobes uniform in width or widest below middle.
3a. Leaves and calyx pubescent; crest of calyx lobes uniform in width........... L. baoxingensis.
3b. Leaves and calyx glabrescent; crest of calyx lobes widest below middle.
4a. Stems and pedicels pubescent......... L. pterantha.
4b. Stems and pedicels glabrescent.
5a. Calyx lobes linear-lanceolate, ca. 1 mm wide………………L. carnata.
5b. Calyx lobes ovate-lanceolate, 3–4 mm wide ………………L. huangsangensis.
In the current study we conducted ML and BI analyses to determine the phylogenetic relationship of the new species. Both analyses generated congruent results and the Bayesian result is shown in Fig 4. The new species is a member of the Chinese sect. Nummularia, and forms a robust monophyletic group (Fig 4), though the phylogenetic position is not resolved.
The Bayesian posterior probabilities are shown below the branches and Maximum Likelihood (ML) bootstrap values above. Clade A, B, and C indicate subg. Lysimachia sect. Hypericoideae, subg. Palladia + subg. Heterostylandra, and subg. Idiophyton respectively. The boxed taxa represent the new species. Vertical bars with labels on the right side represent the series of sect. Hypericoideae proposed by Chen & Hu .
In the classification of Chinese Lysimachia, Chen & Hu  divided the genus into five subgenera, i.e., Idophyton, Lysimachia, Palladia, Heterostylandra and Naumburgia on the basis of the classification of Handel-Mazzetti . More than one third of the species are placed in subgen. Lysimachia sensu Handel-Mazzetti  and Chen & Hu , which is characterized by the yellow flowers that are solitary in the leaf axils or arranged in racemes, panicles or heads, the filaments forming a thin ring adnate to the corolla base, and the anthers opening with slits [5, 34]. The recent molecular evidence [34, 42, 43] reveals that subgen. Lysimachia is paraphyletic and consists of six groups. Sect. Nummularia is the largest section recognized in subgen. Lysimachia by Chen & Hu  and was further divided into ten series by them. Molecular studies  indicated that sect. Nummularia can be divided into two separate groups and Chinese taxa do not group with the type section. Chinese taxa of sect. Nummularia form a sister group with subgenera Pallada and Lysimachiopsis and differ from the latter by the flowers with oil-producing trichomes and filaments forming a thin ring adnate to the corolla base [5, 34]. Here, we treat Chinese taxa of sect. Nummularia as an independent section on the basis of the classification of Chen & Hu  and thus the name Lysimachia sect. Hypericoideae Knuth is the correct name for the section. The monophyly of sect. Hypericoideae has been supported by previous studies . According to the subdivision of sect. Hypericoideae (as sect. Nummularia) by Chen & Hu  who further divided the section into ten series, the new species L. huangsangensis would be placed in ser. Drimarifoliae Hand.-Mazz. Our combined analysis (rbcL, matK, psbA-trnH, and ITS) using Bayesian Inference (BI) (Fig 4) showed that the new species Lysimachia huangsangensis is nested in sect. Hypericoideae. Results support the placement of L. huangsangensis in sect. Hypericoideae and revealed that species in this section included two main groups, L. longipes representing ser. Paracladae, and other taxaof other series in this section. Our results do not support the classification by Chen & Hu . Additional analyses using more molecular markers are necessary to clarify relationships within sect. Hypericoideae.
We delimited species by implementing the phylogenetic species concept [62–65]. In our phylogenetic analysis (Fig 4), Lysimachia huangsangensis forms a trichotomy together with other sampled taxa in sect. Hypericoideae except L. longipes. Although the phylogenetic relationships among sect. Hypericoideae are not well resolved, the recognition of Lysimachia huangsangensis is supported because all three accessions clearly cluster together. Morphologically, the new species can be distinguished from the closely related species by the leaf characters.
Pollen morphology and taxonomy of Lysmiachia was studies in several works [40, 66–73]. Amongst these Bennell & Hu  gave the most comprehensive account of the pollen morphology of Lysimachia and its taxonomic implications. They examined 98 species using light microscope, SEM and TM and ten major pollen types were recognized in relation to the infrageneric classification of Chen & Hu . Pollen grains of sect. Nummularia including sect. Hypericoideae are medium-sized (>24–28 × 23–26) μm, subprolate (P/E<1.33), tricolporate, the tectum partial and coarsely reticulate . In our observations, pollen grains of L. huangsangensis are medium-sized, subprolate, tricolporate, 29.39 (26.3–34.3) ×25.31 (23.2–27.1) μm, P/E = 1.36, and the tectum reticulate (Fig 2E and 2F). It supports the placement of the new species in Sect. Nummularia sensu Chen & Hu  or sect. Hypericoideae.
Surface features of seed coats are surprisingly little affected by the environmental conditions under which a plant grows . Studies of seed morphology with SEM have revealed taxonomically useful microcharacters to support the delimitation of individual or groups of taxa . Shao et al  observed microcharacters of seed surface of eleven Chinese Lysimachia species and divided them into two types, Heterogenea-type and Grammica-type, in relation to the subgeneric classification. Seven species of subgen. Pallada show the Heterogenea-type and four species of sect. Hypericoideae (as Nummulariain the sense of Chen & Hu ) show the Grammica-type with tuberculate ornamentation. Oh et al.  studied seed morphology and character evolution in the genus Lysimachia and its related genera (viz., Anagallis, Ardisiandra, Asterolinon, Glaux, Pelletiera and Trientalis). Seed morphology of 34 species of Lysimachia and 14 species of six related genera were investigated by them . Three major types of seed shapewere identified, i.e., sectoroid (dorsiventrally and/or laterally flattened), polyhedral and coarsely rugose with a concave hilar area. The seed surface pattern of Lysimachia can be divided into six main types, i.e., reticulate, tuberculate, vesiculose, colliculate, undulate and poroid-alveolate. The seed morphological characters imply that the traditional concept of Lysimachia is not monophyletic and this was supported by the molecular studies [34, 41]. Oh et al.  observed seven species of sect. Hypericoideae (as subgenus Lysimachia F by them) and their results showed that the seed shape in sect. Hypericoideae is sectoroid or polyhedral with tuberculate seed surface pattern that is characterized by cells with convex epidermal facets. The observations of Oh et al  are similar to that of Shao et al. . The seed of the new species L. huangsangensis is polyhedral in shape with side-faces slanted towards the ventral face (Fig 2G), outer layer of the surface with convex epidermal cells and the inner layer reticulate (Fig 2H). The seed morphology also supports the placement of the new species in sect. Hypericoideae.
S1 Table. GenBank accession numbers for all the DNA sequences and voucher information.
We are grateful to Prof. Chiming HU (IBSC) for his help during the preparation of the manuscript, Dr. John R.I Wood (OXF) for improving the language, Ms. Jing TIAN (HNNU) for preparing the line drawing, Dr. Shengxiang YU (PE) for preparing the distribution map, the Administrative Office of Huangsang Natural Reserve for assistance during the field work, and the curators of the herbaria of CDBI, IBSC, NAS, P, PE and WUK for access to the specimens for our studies. We also thank Walter Judd and one anonymous reviewer for their useful comments and suggestions to improve the manuscript.
Conceived and designed the experiments: XLY YFD. Performed the experiments: JJZ HFY ZLL. Analyzed the data: JJZ YFD HFY. Contributed reagents/materials/analysis tools: JJZ HFY. Wrote the paper: JJZ XLY YFD HFY.
- 1. Willis JC. A dictionary of the flowering plants and ferns. 8th ed. Cambridge: Cambridge University Press; 1985.
- 2. Heywood VH, Brummitt RK, Culham A, Seberg O. Flowering Plant Families of the World. Kew, England: Royal Botanic Gardens; 2007.
- 3. Mabberley DJ. Mabberley’s Plant-book: a portable dictionary of plants, their classification and uses. 3rd ed. Cambridge: Cambridge University Press; 2008.
- 4. Ståhl B, Anderberg AA. Myrsinaceae. In: Kubitzki K, editor. The families and genera of vascular plants 6. Berlin: Springer; 2004. pp. 266–281.
- 5. Hu CM, Kelso S. Lysimachia. In: Wu ZY, Raven PH, editors. Flora of China. 15. Beijing: Science Press, St. Louis: Missouri Botanical Garden Press;1996.pp. 39–78.
- 6. Kao MT, Peng CI. Lysimachia L. In: Huang TC, editor. Flora of Taiwan. 2nd ed. 4.Taipei: Deptment of Botany, National Taiwan University;1998. pp. 59–75.
- 7. Loc PK, Hu CM. Lysimachia vietnamensis and L. verbascifolia spp. nov. (Primulaceae) from Vietnam. Nordic J Bot. 2011; 29: 601–604.
- 8. Chen FH, Hu CM. Taxonomic and phytogeographic studies on Chinese species of Lysimachia. Acta Phytotax Sin. 1979; 17: 21–53.
- 9. Chen FH, Hu CM, Fang YI, Cheng CZ. Lysimachia. In: Chen FH, Hu CM, editors. Flora Reipublicae Popularis Sinicae 59 Primulaceae (1). Biejing: Science Press; 1989.
- 10. Qian YY. A new variety of Lysimachia violascens. Guihaia. 1998; 18: 354.
- 11. Peng CI, Hu CM. Lysimachia chingshuiensis (Primulaceae), a new species from eastern Taiwan. Bot Bull Acad Sin. 1999; 40: 49–52.
- 12. Zhao ZE, Wu JQ, Wang Y. New taxa of Lysimachiaand Plantago in the Three-Gorge Reservoir Area. J Wuhan Bot Res. 2002; 20: 263–264.
- 13. Zhao ZE, Wu JQ, Li DX. New taxa of Pseudostellaria and Lysimachia from W. Hubei. J Wuhan Bot Res. 2000; 18: 283–285.
- 14. Shao JW, Zhang XP, Guo XH. Lysimachia dextrorsiflora, a new species of Primulaceae from China. Acta Phytotax Sin. 2006; 44: 589–594.
- 15. Shao JW, Zhang XP, Guo XH. A new species of Lysimachia in Primulaceae. Bull Bot Res. 2004; 24: 389–391.
- 16. Zhang CY, Wang FY, Yan HF, Hao G, Hu CM, Ge XJ. Testing DNA barcoding in closely related groups of Lysimachia L. (Myrsinaceae). Mol Ecol. Resour 2012; 12: 98–108. pmid:21967641
- 17. Yan HF, Hao G. Lysimachia huchimingii sp. nov. (Primulaceae) from China. Nordic J Bot. 2012; 30: 443–445.
- 18. Zhang MD, Shui YM, Chen WH, Wei ZD. Lysimachia gesnerioides (Myrsinaceae), a new species from China and Vietnam. Ann Bot Fennici.2006; 43: 317–319.
- 19. Liu K, Hong X, Zhou SB, Cheng YS, Tang CF, Xu HJ. A new species of Lysimachia (Myrsinaceae) from Dabieshan Mountain, China. Plant Syst Evol. 2014; 300:1615–1620.
- 20. Liu K, Zhou SB, Chen YS, Hong X. Lysimachia dabieshanensis sp. nov. (Primulaceae), a new species from Dabieshan Mountain, China. Phytotaxa. 2014; 174(2): 119–122.
- 21. Pax F, Knuth R. Primulaceae. In: Engler A, editor. Das Pflanzenreich 22 (IV, 237). Leipzig: Engelmann; 1905.
- 22. Handel-Mazzetti H. A revision of the Chinese species of Lysimachia. Notes Roy Bot Gard Edinburgh. 1928;16: 51–122.
- 23. Wettstein R. Handbuch der Systematischen Botanik. 4th ed. Leipzig & Wien: Franz Deuticke; 1935.
- 24. Ray JD. The genus Lysimachia in the New World. Illinois Biol Monogr. 1956; 24 (3–4): 1–160.
- 25. Cronquist A. An integrated system of classification of flowering plants. New York: Columbia University Press; 1981.
- 26. Judd WS, Sanders RW, Donoghue MJ. Angiosperm family pairs: preliminary phylogenetic analyses. Harvard Pap Bot. 1994; 5: 1–51.
- 27. Takhtajan AL. Diversity and classification of flowering plants. New York: Columbia University Press; 1997.
- 28. Oh IC, Anderberg AL, Schönenberger J, Anderberg AA. Comparative seed morphology and character evolution in the genus Lysimachia (Myrsinaceae) and related taxa. Plant Syst Evol. 2008; 271: 177–197.
- 29. Anderberg AA, Ståhl B. Phylogenetic interrelationships in the order Primulales, with special emphasis on the family circumscriptions. Canad J Bot. 1995; 73: 1699–1730.
- 30. Anderberg AA, Ståhl B, Källersjö M. Phylogenetic relationships in the Primulales inferred from rbcL sequence data. Plant Syst Evol.1998; 211: 93–102.
- 31. Anderberg AA, Rydin C, Källersjö M. Phylogenetic relationships in the order Ericales s.l.: analyses of molecular data from five genes from the plastid and mitochondrial genomes. Am J Bot. 2002; 89: 677–687. pmid:21665668
- 32. Källersjö M, Bergqvist G, Anderberg AA. Generic realignment in primuloid families of the Ericales s.l.: a phylogenetic analysis based on DNA sequences from three chloroplast genes and morphology. Am J Bot. 2000; 87: 1325–1341. pmid:10991903
- 33. Mast AR, Kelso S, Richards J, Lang DJ, Feller DMS, Conti E. Phylogenetic relationships in Primula L. and related genera (Primulaceae) based on noncoding chloroplast DNA. Int J Plant Sci. 2001; 162: 1381–1400.
- 34. Anderberg AA, Manns U, Källersjö M. Phylogeny and floral evolution of the Lysimachieae (Ericales, Myrsinaceae), evidence from ndhF sequence data. Willdenowia. 2007; 37: 407–421.
- 35. Angiosperm Phylogeny Group. An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG III. Bot J Linn Soc. 2009; 161: 105–121.
- 36. Reveal JL, Chase MW. APGIII: Bibliographical information and synonymy of Magnoliidae. Phytotaxa. 2011; 19: 71–134.
- 37. Reveal JL. An outline of a classification scheme of extant flowering plants. Phytoneuron. 2012; 2012–37: 1–221.
- 38. Stevens PF. Angiosperm phylogeny website. 2012–onward; Version 12. Available: http://www.mobot.org/MOBOT/research/APweb/.
- 39. Klatt FW. Die Gattung Lysimachia L. Abh. Naturwiss. Vereins Hanbburg.1866; 4(4): 1–45.
- 40. Bennell AP, Hu CM. The pollen morphology and taxonomy of Lysimachia. Notes Roy Bot Gard Edinburgh. 1983; 40: 425–458.
- 41. Hao G, Hu CM. Phylogenetic relationships in Lysimachia (Primulaceae): a cladistic analysis. J Trop Subtrop Bot. 2001;9: 93–100.
- 42. Hao G, Yuan YM, Hu CM, Ge XJ, Zhao NX. Molecular phylogeny of Lysimachia (Myrsinaceae) based on chloroplast trnL-F and nuclear ribosomal ITS sequences. Molec Phylogenet Evol. 2004;31: 323–339. pmid:15019628
- 43. Martins L, Oberprieler C, Hellwig FH. A phylogenetic analysis of Primulaceae s.l. based on internal transcribed spacer (ITS) DNA sequence data. Plant Syst Evol. 2003;237: 75–85.
- 44. Manns U, Anderberg AA. Molecular phylogeny of Anagallis (Myrsinaceae) based on ITS, trnL-F, and ndhF sequence data. Int J Plant Sci. 2005; 166: 1019–1028.
- 45. Manns U,Anderberg AA. New combinations and names in Lysimachia (Myrsinaceae) for species of Anagallis, Pelletieraand Trientalis. Willdenowia. 2009;39: 49–54.
- 46. Banfi E, Galasso G, Soldano A. Notes on systematics and taxonomy for the Italian vascular flora 1. Atti Soc Ital Sci Nat Mus Civico Storia Nat Milano. 2005; 146: 219–244.
- 47. Thiers B. Index Herbariorum: A global directory of public herbaria and associated staff. New York Botanical Garden's Virtual Herbarium; 2015. Database. Available: http://sweetgum.nybg.org/ih/.
- 48. Erdtman G. The Acetolysis method. A revised description. Svensk Bot. Tidskr. 1969; 54: 561–564.
- 49. Doyle JJ, Doyle JI. A rapid DNA isolation procedure from small quantities of fresh tissues. Phytochem Bull. 1987; 19: 11–15.
- 50. Chen SL, Yao H, Han JP, Liu C, Song JY, Shi LC, et al. Validation of the ITS2 region as a novel DNA barcode for identifying medicinal plant species. PLoS ONE 2010; 5: e8613. pmid:20062805
- 51. Edgar RC. MUSCLE: multiple sequence alignment with high accuracy and high throughput. Nucleic Acids Res. 2004; 32, 1792–1797. pmid:15034147
- 52. Farris JS, Källersjö M, Kluge AG, Bult C. Testing significance of incongruence. Cladistics. 1994; 10, 315–319.
- 53. Swofford DL. PAUP*: Phylogenetic Analysis Using Parsimony (*and other methods), version 4.0b10. Sunderland, Massachusetts: Sinauer Associates;2002.
- 54. Darlu P, Lecointre G. When does the incongruence length difference test fail? Mol Biol Evol 2002; 19, 432–437. pmid:11919284
- 55. Posada D, Crandall KA. MODELTEST: testing the model of DNA substitution. Bioinformatics. 1998; 14: 817–818. pmid:9918953
- 56. Akaike H. A new look at the statistical model identification. IEEE T Automat Contr. 1974; 19: 716–723.
- 57. Zwickl DJ. Genetic algorithm approaches for the phylogenetic analysis of large biological sequence datasets under the maximum likelihood criterion. PhD Dissertation, The University of Texas. 2006. Available: www.bio.utexas.edu/faculty/antisense/garli/Garli.html.
- 58. Bazinet AL, Zwickl DJ, Cummings MP. A Gateway for Phylogenetic Analysis Powered by Grid Computing Featuring GARLI 2.0. Syst. Biol. 2014; 63: 812–818. pmid:24789072
- 59. Ronquist F, Huelsenbeck JP. MrBayes 3: Bayesian phylogenetic inference under mixed models. Bioinformatics. 2003; 19: 1572–1574. pmid:12912839
- 60. IUCN. IUCN Red List Categories and Criteria. Version 3.1. Second edition. Gland, Switzerland and Cambridge, UK: IUCN; 2012.
- 61. IUCN Standards and Pertition Subcommittee. Guidelines for using the IUCN Red List Categories and Criteria. Version 11. Prepared by the Standards and Petitions Subcommittee of the IUCN Species Survival Commission; 2014. Available: http://www.iucnredlist.org/documents/RedListGuidelines.pdf. Accessed 30 November 2014.
- 62. Donoghue MJ. A critique of the biological species concept and recommendations for a phylogenetic alternative. Bryologist. 1985; 88: 172–181.
- 63. Stuessy TF, Crawford DJ, Soltis DE, Soltis PS. Plant systematic: the origin, interpretation, and ordering of plant biodiversity. Koeltz Scientific Books; 2014.
- 64. Rouhan G, Gaudeul M. Plant taxonomy: a historical persperctive, current challenges and perpectives. In: Besse P, editor. Molecular plant taxonomy. New York: Humana Press; 2014; pp. 1–37.
- 65. Judd WS, Campbell CS, Kellogg EA, Stevens PF, Donoghue MJ. Plant systematic: a phylogenetic approach. 3rd ed. Sunderland, MA: Sinauer Associates; 2008.
- 66. Huynh KL. Le pollen et la systématique chez le genre Lysimachia (Primulaceae). I: Morphologie genera le du pollen et palynotaxonomie. Candollea. 1970; 25: 267–296.
- 67. Huynh KL. Le pollen et la systématique chez le genre Lysimachia(Primulaceae). II: Considerations générale. Candollea. 1971; 26: 279–295.
- 68. Erdtman G. Plant morphology and plan taxonomy: Angiosperms. Amsterdam: Almqvist and Wiksell; 1972
- 69. Huang TC. Pollen flora of Taiwan. Taiwan:National Taiwan University Botanical Departement Press; 1972.
- 70. Punt W, de Leeuw van Weenen JS, van Oostrum WAP. Northwest European Pollen Flora 3, Primulaceae. Rev Palaeobot Palyn. 1974; 17: 31–90.
- 71. Nowicke JW, Skvarla JH. Pollen morphology and the relationship of the Plumbaginaceae, Polygonaceae and the Primulaceae. Smithsonian Contr Bot.1977;37: 1–64.
- 72. Ren XF, Zhou SB, Guo XH, Chen Y. Studies on the pollen morphology of 13 species of Lysimachia in Anhui. J Anhui Norm Univ (Nat Sci). 1994; 17(4): 61–68.
- 73. Shao JW, Zhang XP. Pollen morphology of Lysimachia and its systematic implication. Acta Micropalaeont Sin. 2005; 22: 78–86.
- 74. Barthlott W. Microstructural features of seed surfaces. In: Heywood VH, Moore DM, editors. Current concepts in plant taxonomy. London: Academic Press; 1984. pp. 95–105.
- 75. Juan R, Pastor J, Fernândez I. SEM and Light Microscope Observations on Fruit and Seeds in Scrophulariaceae from Southwest Spain and their Systematic Significance. Ann Bot. 2000; 86: 323–338.
- 76. Shao JW, Zhang XP, Zhu GP. The microcharacteristics of seed surface in Lysimachia (Primulaceae) and its systematic implications. Acta Bot Yunnan. 2006; 28: 378–382.