Oxalis wulingensis (Oxalidaceae), an Unusual New Species from Central China

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Oxalis wulingensis (Oxalidaceae), an Unusual New Species from Central ChinaAuthor(s): Tao Deng , Dai-Gui Zhang , Zhiwei Liu , Gordon C. Tucker , Hang Sun , Jun Wen , and Ze-Long NieSource: Systematic Botany, 38(1):154-161. 2013.Published By: The American Society of Plant TaxonomistsURL: http://www.bioone.org/doi/full/10.1600/036364413X661953

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Systematic Botany (2013), 38(1): pp. 154–161© Copyright 2013 by the American Society of Plant TaxonomistsDOI 10.1600/036364413X661953

Oxalis wulingensis (Oxalidaceae), an Unusual New Species from Central China

Tao Deng,1,2,6 Dai-Gui Zhang,2,6 Zhiwei Liu,3 Gordon C. Tucker,3 Hang Sun,1 Jun Wen,4 and Ze-Long Nie1,5

1Key Laboratory of Biodiversity and Biogeography, Kunming Institute of Botany, Chinese Academy of Sciences,Kunming, Yunnan 650201, China

2Key Laboratory of Plant Resources Conservation and Utilization, Jishou University, Jishou, Hunan 416000, China3Biological Sciences Department, Eastern Illinois University, Charleston, IL 61920, U.S.A.

4Department of Botany, National Museum of Natural History, MRC 166, Smithsonian Institution,Washington, DC 20013-7012, U.S.A.

5Author for correspondence ([email protected])6The authors contributed equally to this study

Communicating Editor: Allan J. Bornstein

Abstract—Oxalis wulingensis, an unusual new species of Oxalidaceae from Hunan and Hubei provinces of central China, is describedand illustrated. Placement of this species within Oxalis was assessed based on DNA analyses of the nuclear internal transcribed spacer (ITS)and morphological comparisons with related species. This new species can be easily distinguished by its long, obtriangular leaflets, thetwo lateral ones arranged at a 180� angle and densely pubescent with brown, villous hairs on both surfaces, pink flowers with lilac veins,and apex of petals obtuse or irregularly denticulate with 3–5 teeth. The chromosome number is 2n = 22. With the addition of O. wulingensis,which is the only species endemic to China, a total of seven native Oxalis occur in the country. A taxonomic key to all Chinese species ofOxalis is also provided.

Keywords—chromosome number, ITS, molecular phylogeny, Wuling Mountains.

Oxalis L. is a cosmopolitan genus with approximately500 species, most of which occur in southern Africa and theAmericas (De Azkue 2000). A few cosmopolitan and endemicspecies are found in Eurasia and Oceania (Knuth 1930;Lourteig 1979). Despite many well-known and easily recog-nized species, members of the genus are often difficult toidentify. Huang et al. (1998), applying a narrow species con-cept, recognized five species (O. acetosella L., O. bowiei Ait. exG. Don,O. corniculata L.,O. corymbosaDC. andO. pes-caprae L.)and three subspecies [O. acetosella subsp. griffithii (Edgew. &Hook. f.) Hara, O. acetosella subsp. japonica (Franch. & Sav.)Hara and O. acetosella subsp. leucolepis (Diels) C. C. Huang &L. R. Xu] ofOxalis in China. Lourteig (2000), however, treatedthese subspecies as three distinct species (i.e. O. griffithiiEdgew. & Hook. f., O. leucolepis Diels, and O. obtriangulataMaxim.) and included them in sect. Oxalis subsect. Oxalis,which also includes O. acetosella, O. oregana Nutt. and O.trilliifolia Hook. By following Lourteig (2000), Liu and Watson(2009) undertook a detailed revision of Oxalis in China andrecognized eight species, six native (O. acetosella,O. corniculata,O. griffithii, O. leucolepis, O. obtriangulata, and O. stricta L.) andtwo introduced (O. corymbosa and O. pes-caprae). Oxalisacetosella subsp. formosana Terao was not accepted by Lourteig(2000) or Liu and Watson (2009), and they subsumed it intoO. griffithii as a synonym. Although Lourteig (2000) reducedO. corymbosa to a variety of O. debilis Kunth [i.e. O. debilis var.corymbosa (DC.) Lourteig], we follow Liu &Watson (2009) andrecognize it as a distinct species in this study.The Wuling Mountains region is located in central China,

bordering Hunan to the southeast, Hubei to the northeast,Chongqing to the northwest, and Guizhou to the southwest.This region contains high species diversity, is rich in ende-mism and relict taxa (Chen et al. 2000), and is considered thecore area of “western Hubei-eastern Sichuan center”, one ofthree centers of plant endemism in China. Despite their richspecies diversity, the Wuling Mountains are also known asan under-explored region. Therefore, a large number ofunique habitats may harbor specialized species, but theyhave not been studied systematically. A recent, in-depth sur-

vey in the region has led to the discovery of many newspecies (Li and Liu 2002; Li and Chen 2006; Zhang et al.2008; Liu et al. 2009, 2010, 2011).

During a field excursion to study the biodiversity of the“Wuling Mountains National Nature Reserve”, an unusualisolated population of Oxalis was discovered. Subsequenttaxonomic studies revealed that plants of this populationmorphologically differed from all known species of Oxalis.Additional expeditions occurred in March 2009 and 2010 toBadagongshan Mountain in Hunan and careful observationswere made of plants in the field. Some plants were alsotransplanted to the greenhouse in Jishou University andKunming Institute of Botany, Chinese Academy of Sciencesfor further observation. The results of these studies con-firmed that the plants represent an undescribed species.Further research was subsequently conducted, includingfield and herbarium comparisons, karyotype studies, andphylogenetic analysis based on ITS sequence data of thisnew taxon and related species within the genus. All lines ofevidence support the status of these plants as a new species,which is described herein.

Materials and Methods

Morphological Assessment—Morphology of the newly collected speci-mens was examined and compared to that of Oxalis acetosella, O. griffithii,O. leucolepis and O. obtriangulata based on specimens from PE and KUN(acronyms follow Holmgren et al. 1990), as well as fresh materialsof O. acetosella and O. griffithii obtained from the field. Ecological traits ofthese species were also included in the comparative analysis. A total of36 individuals of the new species were examined from two populations,(Deng, Zhang, & Nie 544 from Hunan Province andDeng, Zhang, & Nie 259from Hubei Province).

Chromosomal Analysis—Ten plants from the Hunan Province popula-tion and five plants from the Hubei Province population were sampled todetermine the chromosome number of this new taxon. Living plants werecollected from these two populations and cultivated in pots in the glass-house at KUN. Root tips were pretreated with 0.002 M 8-hydroxyquinolineat room temperature for 3–5 h before being fixed in Carnoy’s solution(glacial acetic acid: absolute ethanol = 1:3), followed by maceration in a1:1 mixture of 45% acetic acid and 1 M HCl at 60�C for 2.5 min, thenstained and squashed in Carbol Fuchsine. Karyotype formulae were

154

based on measurements of mitotic-metaphase chromosomes taken fromphotographs. For karyotypic analysis, measurements of five cells weremade in most cases. The symbols used to describe the karyotypes fol-lowed Levan et al. (1964). Voucher specimens are deposited in KUN.

DNA Sequencing and Molecular Analyses—Phylogenetic reconstruc-tion was based on DNA sequence data obtained from the nuclear InternalTranscribed Spacer (ITS). Total genomic DNA was extracted from driedleaves following a modified CTAB method (Rogers and Bendich 1985)and used as a template in the polymerase chain reaction (PCR). Sequencealignment was initially performed using the program CLUSTALX ver-sion 1.81 (Thompson et al. 1997) in the multiple alignment routine usingdefault settings and the accurate search option followed by manualadjustment in the program BioEdit version 7.0 (Hall 1999). Availablesequence data were retrieved from GenBank. Voucher information andaccession numbers are provided in Appendix 1. Sequence alignments ofthe ITS dataset and phylogenetic trees are available from TreeBASE(study number S13321).

Phylogenetic trees were constructed using maximum parsimony(MP), Maximum Likelihood (ML), and Bayesian inferences (BI). The MPanalyses were conducted using PAUP* version 4.0b10 (Swofford 2003).Character state changes were equally weighted and gaps were treated asmissing data. The most parsimonious trees were obtained with heuristicsearches of 1,000 replicates, with random stepwise sequence addition,tree bisection - reconnection (TBR) branch swapping, collapse of zero-length branches, multiple tree option in effect, and saving 100 trees fromeach random sequence addition. Bootstrap values of the internal nodeswere obtained with 1,000 replicates (Felsenstein 1985). In each replicate,10 random sequence additions were performed, followed by TBR swap-ping, keeping no more than 1,000 trees per replicate.

Prior to these analytical approaches, the best fit model of nucleotidesubstitutions for the ITS sequence data was explored. A hierarchical like-lihood ratio test as implemented in MrModeltest 2.3 (Nylander 2004)suggested the generalized time reversible model (GTR + I + G) as the bestmodel. In the ML and BI analyses these substitution models and param-eters were adjusted according to the estimates of MrModeltest. ML anal-ysis was performed in GARLI 2.0 (Zwickl 2006) and bootstrap supportvalues were estimated from 100 replicates.

Bayesian inference was implemented using MrBayes version 3.1.2(Huelsenbeck and Ronquist 2001). Bayesian tree topology was deter-mined from two independent Markov chain Monte Carlo (MCMC) runsof four incrementally heated chains. Runs were performed for 5 milliongenerations with sampling of trees every 500 generations. When the log-likelihood scores were found to have stabilized, a consensus tree wascalculated after omitting the first ca. 10% of trees as burn-in. Theremaining trees were imported into PAUP* and a 50% majority-ruleconsensus tree was produced to obtain posterior probabilities (PP) ofthe clades.

Results

Morphological Assessment—Morphological data sug-gested that the new species is related to members of sect.Oxalis subsect. Oxalis. Characters shared by species in thisgroup include: habit acaulescent; bulbs absent; rhizome creep-ing at or just below the soil surface and covered with persis-tent, scale-like leaf bases; leaves 3-foliolate; flowers solitarywith petals white to purple, but not yellow (Lourteig 2000).Numerous features, including leaflet shape, arrangement, andindumentum, plus petal length, collectively differentiate thenew taxon from other species in this subsection (Table 1).Within the two populations examined, only a single stylemorph of flowers was found for the new species, i.e. long pistil(ca. 2 cm) with short stamens (ca. 1.0 cm). This contrasts withotherOxalis species from China (e.g.O. pes-caprae), which havethree style morphs.Chromosome Data—In the interphase nuclei, a few darkly

stained, condensed bodies were observed, but their bound-aries were not clear because the other part was also stainedfairly well but unevenly (Fig. 1A). The prophase chromo-somes displayed a distinctly continuous condensation pat-tern (Fig. 1B). The metaphase chromosomes of all individualswere determined to be 2n = 22 (Fig. 1C). Based on the nomen-clature of Levan et al. (1964), O. wulingensis has 18 mediancentromeric (m) and four submedian centromeric (sm) chro-mosomes (Fig. 1D); i.e. 2n = 22 = 18m + 4sm.Phylogenetic Position—The Bayesian tree is presented in

Fig. 2 with MP, ML bootstrap and PP support values for eachclade. Oxalis sect. Oxalis subsect. Oxalis is supported as amonophyletic group (MP bootstrap = 100%, PP = 100%, MLbootstrap = 99%). Within this clade, O. wulingensis is sister toO. griffithii (MP bootstrap = 82%, PP = 98%, and ML boot-strap = 89%) (Fig. 2).

Taxonomic Treatment

Morphological data clearly confirm the newly collectedtaxon represents a distinct new species of Oxalis. Both

Table 1. Morphological comparison between Oxalis wulingensis and other species within sect. Oxalis subsect. Oxalis.

Characters O. wulingensis O.acetosella O. griffithii O. leucolepis O. obtriangulata

Rhizomes(including scales)

Ca. 10 mm diameter Ca. 3 mm diameter 6–12 mm diameter 1.5–2 mm diameter 5–8 mm diameter

Two lateral leafletsarrangement

180� angle 120� angle 120� angle 120� angle 120� angle

Leaflet shape Long obtriangular Obcordate Obtriangular Rounded-obcordate Broadly obtriangularLeaflet size 2.2–3.1 + 1.6–2.5 cm 0.5–2 + 0.8–3 cm 1–2.5(–4.5) +

1.5–3.5(–5.5) cm1–1.8 + 1.1–2 cm 1–1.8 + 1.4–2.2 cm

Leaflet apex Broadly emarginate Deeply emarginate Broadly emarginateto subtruncate

Deeply emarginate Truncate to subtruncate

Leaflet indumentum Both surfaces villous(densely coveredwith long, brown hairs)

Abaxially pubescent,adaxially glabrous



Abaxially pubescent orglabrous, adaxiallyglabrous

Leaflet abaxialsurface color

Purple Green Green Purple Green

Petal length Ca. 2.5 cm (1.2–) 1.5–2.2 cm 1.2–1.6 (–2) cm 0.9–1.4 cm Ca. 1.6 cmPetal apex Obtuse or irregularly

denticulateRetuse to deeply

emarginateRetuse to deeply

emarginateUnknown Emarginate

Petal color Pink White White, rarely pink(Hubei and Hunan)

White White

Capsules Ovoid, 5–7 mm long Angular-ovoid,3–4 mm long

Oblong-conic,5–13 + 5–6 mm

Unknown Long-conical,3–4 + 0.6–0.8 cm

Flowering time March July to August April to September July to August May -June

2013] DENG ET AL.: OXALIS WULINGENSIS, A NEW SPECIES FROM CHINA 155

cytological and molecular data indicate a close affinity withO. acetosella and O. griffithii in sect. Oxalis subsect. Oxalis. Itis thus described as follows:

Oxalis wulingensis T. Deng, D. G. Zhang & Z. L. Nie, sp.nov. -TYPE: CHINA. Hunan Province: Sangzhi,Badagongshan National Nature Reserve, moist limestonerocks in valley and Cavern, ca. 250 m, 2 April 2007,Deng, Zhang & Nie 544 (holotype: KUN!; isotype: PE).

Haec species similis Oxalis wulingensis et O. griffithii foliolalongorum obtriangularis, ad angulum 180�dispositus, ramisdese utrinque brunneus villosus, petala roseus, apex obtususaut 3–5 irregulariter denticulatus, florescentia martius differt.

Perennial herb, apparently acaulescent, 8–10 cm tall; rhi-zome creeping underground, densely covered by dark brown,scale-like remains of leaf bases, ca. 11 mm thick includingscales, root system fibrous. Leaves basal, 3-foliolate, thetwo lateral leaflets arranged at a 180� angle; petioles 5–7 cmlong, densely covered with long, brown, villous hairs overtheir entire length; leaflets without calli, long obtriangular,2.2–3.1 + 1.6–2.5 cm (length to width ratio 1.3–1.6), bothsurfaces densely villous with long, brown hairs, sometimesglabrescent on abaxial surface with scattered hairs restrictedto leaflet margin and veins in mature leaves, apex broadlyemarginate, base cuneiform, lobe apices obtuse. Inflorescence1-flowered, nodding; peduncles 10–12 cm long, longer thanleaves; bracts at middle of flowering stalk, broadly triangu-lar, ca. 3.0 mm long, with dense trichomes along midvein andmargins. Flowers with sepals lacking calli, oblong-lanceolate,ca. 5.0 + 2.0 mm, green, surface and margins with somehairs, persistent; petals pink with lilac veins, oblong, ca.2.5 + 1.0 cm, apex obtuse or irregularly denticulate with 3–5 teeth; stamens 10, alternately long and short, the longerones ca. 1.5 cm, the shorter ones ca. 1.0 cm, all basally con-nate, filaments aubergine, glabrous, anthers white; gynoe-cium ca. 2.0 cm long, ovary glabrous, locules 5, each with asingle ovule, styles 5, separate, stigmas green, capitate. Fruitan oblong capsule, 5.0–7.0 mm long, nodding, with 5 alar

ridges; seeds ovoid, ca.2.1 mm long, with 4–5 distinct ridgeson both surfaces, dark brown when dry (Figs. 3, 4).

Additional Specimen Examined—

CHINA. Hubei Province: Xuan’en, Changtan, Banzhuyuan,humid hillside, ca. 1100 m, 5 March 2010, Deng, Zhang, &Nie 259 (KUN).

Distribution and Ecology

The distribution of species within sect. Oxalis subsect.Oxalis in China is presented in Fig. 5. Both O. acetosella andO. griffithii are widely distributed and have colonized mul-tiple habitats between 800 and 3,700 m. Oxalis acetosellamainly occurs in northeast, north, northwest and southwestChina, whereas O. griffithii occurs throughout eastern, centraland southwest China. Oxalis obtriangulata is restricted to low-lying areas of northeast China. In contrast, O. leucolepis is verylimited in distribution in the Hengduan Mountains region,occurring at higher elevations from 2,800–4,000 m in humidhabitats under the mixed forests or among moss and boul-ders. The newly discovered taxon is the only endemic speciesof Oxalis in China, and is so far known only from a restrictedarea in northwestern Hunan and southwestern Hubei Prov-inces in the Wuling Mountains region of central China. Fur-thermore, it is currently only known from limestone habitat.Despite an apparently restricted distribution range, the plantswere found to be locally abundant. Plants were scattered onmoist rocks in the valley or in shady crevices below rocks, atelevations between 250–1,200 m. Oxalis wulingensis flowers inMarch, and fruits from April to May.

Discussion

The morphological attributes (Table 1), chromosome num-ber, andmolecular phylogeny confirm a close affinity ofOxaliswulingensis with taxa of sect. Oxalis subsect. Oxalis. Similarto members of this subsection, O. wulingensis possesses anacaulescent habit, bulbs are absent, rhizomes creep at or just

Fig. 1. Interphase nuclei (A), mitotic prophase (B), metaphase (C), chromosomes and karyotype (D) of Oxalis wulingensis. m: median centromericchromosome; sm: submedian centromeric chromosome.

156 SYSTEMATIC BOTANY [Volume 38

below the soil surface, flowers are solitary and the petals arewhite to purple, but not yellow; this combination of featuresdiffers from other species of Oxalis in China.

Within Oxalis, the haploid chromosome number (n) isoften 5, 6, 7, or 9, and n = 11, as observed in O. wulingensis,is very rare (De Azkue 2000). Marks (1956) identified a basicchromosome number of x = 7 as the most common con-dition in the genus. De Azkue (2000) advocated that spe-cies with the basic number n =11 may have a polyploid oraneuploid origin and are likely derived. The chromosomenumbers of O. acetosella and O. griffithii are also n = 11(Nakajima 1936; Dobes et al. 1997; Lovkvist and Hultgard1999), which support their close relationship to O. wulingensisin subsect. Oxalis.

Furthermore, the Bayesian consensus tree based on ITSsequence data clearly places the new species in sect. Oxalis

subsect. Oxalis (Fig. 2), corresponding to the O. acetosellaclade in Oberlander et al. (2009, 2011). The results supporta sister-species relationship between O. wulingensis andO. griffithii (Fig. 2). The two species, especially in centralChina, share the unique feature of having pink to pinkish-purple petals. Nevertheless, the two species are distinctmorphologically, especially with respect to leaf architecture,petal shape, and capsule shape. Oxalis wulingensis hastwo lateral leaflets arranged at a 180� angle, long obtriangularin shape, densely pubescent with brown, villous hairs onboth surfaces (vs. 120�, obtriangular, abaxially pubescent,adaxially glabrous), apex of petals obtuse or irregularly den-ticulate (vs. apex broadly emarginate to subtruncate), andcapsules ovoid (vs. oblong-conic).It is noteworthy that both O. wulingensis and O. griffithii

were found to occur on the same mountains in the Wuling

Fig. 2. Bayesian consensus tree of Oxalis sect. Oxalis subsect. Oxalis and related species. Numbers above branches are MP bootstrap values andBayesian posterior probabilities; numbers below branches are ML bootstrap values. Oxalis sect. Oxalis subsect. Oxalis is indicated within the greyrectangle and the new species is shown in bold.


Fig. 3. Oxalis wulingensis T. Deng, D. G. Zhang & Z. L. Nie. A, Habit; B, Individuals; C, Upper surface of leaves; D, Lower surface of leaves;E, Inflorescence; F, Flower in front view; G, Flower in side view; H, Fruits; I, Seed.


Fig. 4. Oxalis wulingensis T. Deng, D. G. Zhang & Z. L. Nie. a, Habit; b, Flower; c, Fruit; d, Seed. (All from Deng, Zhang, & Nie 544, KUN).


Mountains region (Badagongshan Mountain in SangzhiCounty of Hunan and Qizimeishan Mountain in Xuan’enCounty of Hubei), but it seems that the two species neveroccur sympatrically. Both species grow in quite different hab-itats: O. griffithii occurs in sandy areas within forests andthickets or open places along streamsides; O. wulingensis, incontrast, is narrowly restricted to a limestone habitat andgrows on moist rocks in mountain valleys or in shady crevicesbelow rocks. The two species also differ in phenology, with O.griffithii usually flowering from April to September, and O.wulingensis blooming in early March. No intermediate formsbetween the two species were found on these mountains.

As shown in Table 1, O. wulingensis may be confused withO. acetosella and O. obtriangulata due to similarities in rhi-zome size, leaflet shape, and leaf size. However, they bothdiffer from O. wulingensis in leaflet arrangement andindumentum, petal morphology and capsule shape, and gen-erally occur in more northern regions. The new species is alsosomewhat similar to O. leucolepis by having adaxially purpleleaflets, but differs in leaflet shape (long obtriangular vs.rounded-obcordate) and size (2.2–3.1 + 1.6–2.5 cm vs. 1–1.8 + 1.1–2 cm), and the latter species is endemic to theHimalayan region. All species of Oxalis in China can be read-ily identified using the following key:

Key to Oxalis in China

1. Bulbs present.2. Petals yellow; leaves glabrous, semi-succulent . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . O. pes-caprae2. Petals pink; leaves hairy above and below, membranous . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . O. corymbosa

1. Bulbs absent.3. Petals yellow; flowers organized in umbellate or cymose inflorescences, usually not solitary.

4. Plants creeping to caespitose, stolons absent; flowers in an umbellate inflorescence or solitary; fruiting pedicelsdeflexed to horizontal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . O. corniculata

4. Plants erect to decumbent, stolons present; flowers in a cymose inflorescence; fruiting pedicels erect . . . . . . . . . . . . . . . . . . . . . . . . . . O. stricta3. Petals white to purple, not yellow; flowers solitary.

5. Two lateral leaflets arranged at 180� angle, both surfaces densely covered with brown villous hairs; petals pink . . . . . . . . . . . O. wulingensis5. Two lateral leaflets arranged at 120� angle, abaxially pubescent and adaxially glabrous; petals white

(O. griffithii rarely pink in Hubei and Hunan).

Fig. 5. Distribution map of Oxalis wulingensis and other species within Oxalis sect. Oxalis subsect. Oxalis in China.


6. Rhizome less than 3 mm thick (including scales).7. Rhizome less than 2 mm thick; leaves abaxially purple . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . O. leucolepis7. Rhizome ca. 3 mm thick; leaves abaxially green . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . O. acetosella

6. Rhizome more than 5 mm thick (including scales).8. Leaflet blade obtriangular; capsules subglobose to oblong, less than 1.5 cm long . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . O. griffithii8. Leaflet blade broadly obtriangular; capsules long-conical, more than 2.5 cm long . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . O. obtriangulata

Acknowledgments. We thank Kai Wen and Xiao-Shuang Zhang formaking the illustrations, Profs. Qin-Er Yang and Jing-Yi Peng for identi-fying specimens, and Drs. Amy Eisenberg and Jian-Wen Zhang for com-ments on the manuscript. This work was supported by the NaturalScience Foundation of China (NSFC 30970193, 31061160184), and theNational Nature Science & Technology Infrastructure Project of Ministryof Science and Technology (Grant no. 2005DKA21404).

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Appendix 1. Taxon name, voucher/source information, andGenbank accessions for ITS sequences used in this study. Herbariumabbreviations follow Index Herbariorum.

Biophytum abyssinicum Steud. ex A. Rich., Oberlander et al. 2009,EU436864; Oxalis acetosella L., Oberlander et al. 2009, EU436870; Oxalisarticulata Savigny, Tosto and Hopp 1996, Z66545; Oxalis barrelieri L.,Oberlander et al. 2009, EU436866;Oxalis corniculata L., Oberlander et al.2009, EU436867 and Nie 3660 (KUN), JX445129; Oxalis corymbosa DC.,Deng, Zhang & Nie 542 (KUN), JX445130; Oxalis dolichopoda Diels,Emshwiller and Doyle 1998, U74267; Oxalis griffithii Edgew. & Hook.f., Deng, Zhang & Nie 546 (KUN), JX445131; Oxalis micrantha Bertero exSavi, Heibl and Renner 2012, JN634744; Oxalis obtriangulata Maxim.,Koo and Lee 2007, DQ151555; Oxalis oregana Nutt., Heibl and Renner2012, JN159893; Oxalis pachyrrhiza Wedd., Emshwiller and Doyle 1998,U74275; Oxalis perdicaria (Molina) Bertero, Oberlander et al. 2009,EU436878;Oxalis pes-caprae L., Oberlander et al. 2009, EU436882;Oxalisstricta L., Oberlander et al. 2009, EU436869; Oxalis triangularis A.St.-Hil., Oberlander et al. 2009, FJ410328; Oxalis valdiviensis Barneoud,Oberlander et al. 2009, EU436873; Oxalis vulcanicola Donn. Sm.,Oberlander et al. 2009, EU436872; Oxalis wulingensis Deng, Zhang &Nie, Deng, Zhang & Nie 544 (KUN), JX445132.


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Oxalis wulingensis (Oxalidaceae), an Unusual New Species from Central China