Abstract
Asterquanzhouensissp. nov. (Asteraceae) from Fujian, eastern China, is described and illustrated. It grows on rocks in the riparian zone. Morphological, cytological and molecular investigations of A.quanzhouensis were carried out. The morphological data and phylogenetic analysis based on combined ITS, ETS and trnL-F dataset suggest that A.quanzhouensis is a separate species closely related to A.tonglingensis. The new species differs from the latter by the shorter stem length, leaf morphology, colour of phyllaries, number of ray florets, and achene shape. The cytological observation shows that the new species is diploid with a karyotype of 2n = 18.
Keywords: Asteraceae, Asterquanzhouensis , new species, taxonomy
Introduction
The genus Aster L. in its recent circumscription is restricted to Eurasia and comprises ~ 150 species, of which 123 occur in China (Chen et al. 2011), a main diversity centre of Aster (Li et al. 2012). Recently, ten new Aster species have been described, and almost all these species have a narrow distribution pattern known from only one or two populations in different regions of China (Zhang et al. 2015, 2019; Li et al. 2017, 2020; Xiao et al. 2019a, b, 2020, 2021; Xiong et al. 2019).
Recently, Guo-Jiao Yan, a young amateur naturalist and one of the authors of this paper, collected some unique samples from the riversides of the Min and Jin rivers, Quanzhou city, Fujian, eastern China. The morphological, cytological and phylogenetic data show that the specimens represent an undescribed species, which is reported herein.
Materials and methods
Material collection
Specimens of the new taxon were collected in Dehua and Yongchun counties (Fig. 1), Fujian, China. We collected leaf material and dried it with silica gel for molecular experiments. The voucher specimens were deposited at the Herbarium of Hunan Normal University (HNNU) and Jiangxi Agricultural University (JXAU).
Figure 1.
Distribution of Asterquanzhouensis (black circle) and A.tonglingensis (black triangle).
Morphological observations
The description of the new species is based on living material, dry specimens and FAA-fixed materials. Twenty-one individuals were examined. The morphological comparison with Astertonglingensis G.J.Zhang & T.G.Gao is based on the study of herbarium specimens, from PE, HNNU and JAXU. We compared the shape and size of the leaves, length of stems, phyllaries, number of florets, and achenes.
Cytology
Excised root tips from the cultivated plants of the new species were pretreated with 0.1% colchicine at 10 °C for 4 h, then fixed in Carnoy’s solution (95% ethanol and glacial acetic acid in 3:1 ratio) at 20 °C for 12 h. The root tips were then macerated in 1 M hydrochloric acid at 60 °C for 10 min, stained in Carbol fuchsin solution, washed in distilled water for 30 min and finally depigmented and squashed in 45% acetic acid (Li et al. 2011). Karyotype formulae were calculated based on measurements of mitotic metaphase chromosomes taken from photographs. The symbols used to describe the karyotypes followed Levan et al. (1964).
Taxon sampling, DNA extraction, PCR reaction and sequencing
Nuclear ribosomal DNA ITS and ETS sequences and plastid DNA trnL-F sequences of 66 species and varieties, representing major clades of the genus Aster and its relatives (Li et al. 2012, 2017, 2020; Zhang et al. 2015, 2019; Xiao et al. 2019a, b, 2020, 2021), were downloaded from GenBank (Appendix 1). Besides, eleven newly sequenced accessions are included from Dehua and Yongchun counties two individuals of Asterquanzhouensis (Appendix 1). The names of the taxa mentioned above follow Chen et al. (2011). Grangeamaderaspatana (L.) Poir. and Dichrocephalaintegrifolia (L.f.) Kuntze were selected as outgroups following Li et al. (2012). Voucher specimens of newly sequenced material were deposited in HNNU. Total DNA extraction, PCR and sequencing were carried out according to Li et al. (2012).
Phylogenetic analysis
Boundaries of the ITS, ETS and trnL-F regions were determined through comparison with previously published sequences (Li et al. 2012). DNA sequences were aligned initially using Clustal X1.83 (Jeanmougin et al. 1998), performed by MUSCLEv3.8.31 (Edgar 2004), and adjusted manually in PhyDE ver0.9971 (Müller et al. 2010). The optimal model of DNA substitutions was selected using the Akaike information criterion (Akaike 1973) as applied in jModelTest 2.1.4 (Darriba et al. 2012) prior to the maximum likelihood (ML) analyses and Bayesian inference (BI). The best fit models for ITS, ETS and trnL-F were GTR + G, GTR + I + G and TVM+I, respectively. Phylogenetic trees were constructed using maximum likelihood (ML) and Bayesian inference (BI). Maximum likelihood (ML) and Bayesian inference (BI) analyses were conducted using RAxML 7.2.6 and MrBayes 3.1.2 (Huelsenbeck and Ronquist 2001; Stamatakis 2006), respectively. For BI, four chains, each starting with a random tree, were run for 1,000,000 generations with trees sampled every 1000 generations. The average standard deviation of split frequencies (< 0.01) was used to assess the convergence of the two runs. After the first ca. 25% discarded as burn-in, the remaining trees were imported into PAUP* v.4.0b10 and a 50% majority-rule consensus tree was produced to obtain posterior probabilities (PP) of the clades. Before the datasets were combined, the incongruence length difference test (Farris et al. 1994) was performed on PAUP* v.4.0b10 (Swofford 2001).
Results
. Aster quanzhouensis
M.Tang, G.J.Yan & W.P.Li sp. nov.
E9396B43-12C0-59A1-90E9-86F0F7830DCF
urn:lsid:ipni.org:names:77297480-1
Figure 2.
Images of living plants of AsterquanzhouensisA habitat B habit C seedling D steam E rosulate leaves F top view of the capitulum G a disk floret (left) and a ray floret (right) H style branches of a disk floret I receptacle J fruits K dorsal view of a capitulum L phyllaries (from outer to inner, left to right).
Figure 3.
Holotype of Asterquanzhouensis M.Tang, G.J.Yan & W.P.Li.
Type.
China, Fujian province, Quanzhou city, Dehua county, Nancheng town, alt. ca. 500 m, 25°34.20'N, 118°29.65'E, 5 Oct 2021, Guo-Jiao Yan, YGJ2110003 (Holotype: HNNU!, isotypes: HNNU!, JXAU!) (Fig. 3).
Additional collection seen.
China. Fujian province, Quanzhou city, Yongchun county, alt. ca. 500 m, 25°24'N, 118°21'E, 30 Nov 2021, Guo-Jiao Yan, YGJ21113001 (HNNU!).
Diagnosis.
Asterquanzhouensis differs from A.tonglingensis by its stems only 21–30 (60) cm (vs. 70–100 cm) long, narrowly lanceolate (vs. lanceolate) rosulate leaves, purplish-red (vs. green) apices of the phyllaries, 9–20 (40) (vs. more than 30) capitula, 7–11 (vs. ca. 15) ray florets, 11–14 × ca. 2 mm (vs. 7–10 × ca. 2 mm) lamina, two-or three-ribbed (vs. 4-ribbed) achenes and flowering period (Sep to early Dec vs. Jul) (Figs 2, 3, Table 1).
Table 1.
Comparison of Asterquanzhouensis and A.tonglingensis. The data of the latter species were taken from Zhang et al. (2019).
| Characters | Asterquanzhouensis | A.tonglingensis |
|---|---|---|
| Stem | 21–30(60) cm, solitary | 70–100 cm, solitary or two to three |
| Basal leaves | narrowly lanceolate, 4–13 × 0.4–1.7 cm | lanceolate, 4–18 × 0.8–2.5 cm |
| Capitula | 9–20 (40) | More than 30 |
| Phyllaries | 5–7-seriate, apex purplish-red | 5–7-seriate, apex green |
| Ray florets | 7–11 | ca. 15 |
| Achenes | 2–3-ribbed | 4-ribbed |
| Pappus | 8–11 mm | ca. 7 mm |
| Flowering period | Sep to early Dec | Jul |
Description.
Perennial herb, 21–30 (60) cm high. Rhizomes thin, with adventitious roots, stolons absent. Stem solitary, erect, unbranched except for inflorescence, glabrous or puberulent in upper part. Leaves slightly leathery, narrowly lanceolate, apex acute, base gradually narrowing, subclasping, abaxially light green, adaxially dark green and glossy, 3-veined, midvein abaxially prominent; rosulate leaves 4–13 × 0.4–1.7 cm, margin serrate, petiole 3–11 cm long, both surfaces glabrous; lower cauline leaves persistent at anthesis or rarely withered, 3–10 × 0.3–0.8 cm, sessile or with obscure petioles, margin entire or serrate, abaxially glabrous, adaxially sparsely strigose; middle cauline leaves sessile or with obscure petiole, 4–7 × 0.3–0.4 cm, margin entire or serrate, abaxially glabrous, adaxially sparsely strigose; upper leaves sessile, margin entire. Capitula 9–20 (40) in a terminal corymbose cyme, peduncle puberulent. Involucre campanulate, 5–8 mm in diameter; phyllaries in 5–7 rows, imbricate, lanceolate, the outer rows shorter than the inner ones, reflexed, densely pilose, with ciliate margin; outer phyllaries 3.2–6.2 × 1.1–2 mm; middle phyllaries 4.6–13 × 1.5–2.2 mm, with narrowly scarious margin, tip purplish-red; inner phyllaries 10.1–13.0 ×1.5–1.7 mm, with broadly scarious margin, tip purplish-red. Receptacles flat, alveolate. Ray florets 7–11, female, tube ca. 4 mm, glabrous, ligules whitish, lanceolate, 11–14 × ca. 2 mm, with four nerves, apex with two or three teeth. Disc florets (11) 18–24, hermaphrodite, yellow, tube puberulent, ca. 3 mm, thin but expanded at base, 5-lobed, lobes spreading to reflexed, narrowly triangular, unequal, 1.1–1.5 mm, glandular; anthers ca. 1.8 mm (excluding collar), apical appendage 0.35–0.45 mm long, narrowly lanceolate, anther collar ca. 0.4 mm long; style arm appendage lanceolate, ca. 2.5 mm, stigmatic lines 1.2–1.4 mm, equal to the sterile style tip appendages. Achenes 4.5–5.5 × 0.9–1.4 mm, narrowly oblong, strigose, eglandular, two- or three-ribbed. Pappus uniseriate, dirty white, 8–11 mm, nearly as long as disc corolla at anthesis.
Phenology.
Flowering from September to early December and fruiting from October to December.
Etymology.
The species is named after its type locality, Quanzhou city, Fujian province, China.
Vernacular name.
quán zhōu zĭ wăn (Chinese pronunciation); 泉州紫菀 (Chinese name).
Distribution and habitat.
Asterquanzhouensis is known from Dehua and Yongchun counties, Quanzhou city, Fujian province, China. The new species grows on rocks in riparian habitats at an altitude of ca. 500 m a.s.l.
Conservation status.
Asterquanzhouensis seems to be a narrowly distributed species, currently known only in rocky areas along two streams (Jin river and Min river) in Quanzhou city, and each population with ca. 150 (total < 1000) individuals were found. The habitat of A.quanzhouensis is easily disturbed or damaged. Further fieldwork is needed to evaluate the exact distribution of the species, and it is possible that other populations could be found in similar habitats of the Jin and Min rivers. Therefore, we only temporarily assign the species to the category DD (Data Deficient) according to the International Union for Conservation of Nature (IUCN 2022).
Cytology
The somatic chromosomes of the new species at metaphase are illustrated in Fig. 4. The two populations have a same karyotype formula, 2n = 18, and Stebbins’ 1A-type (Stebbins 1971), but differs in ratio of long to short arm of chromosomes (the former is 1.02–1.55, while the latter 1.06–1.45), the chromosomes length (the former is 1.49–2.72, while the latter 1.71–2.77), and the AI value (the former is 0.54, while the latter 0.57).
Figure 4.
Micrographs of somatic metaphase chromosomes (A, C) and the karyotype (B, D) of Asterquanzhouensis from two different populations. (A, B Dehua county, Quanzhou, Fujian, China; C, D Yongchun county, Quanzhou, Fujian, China).
Molecular phylogeny
The aligned lengths of ITS, ETS and trnL-F are 647 bp, 568 bp and 957 bp, respectively, yielding a concatenated alignment of 2172 bp. Character state changes were equally weighted and gaps were treated as missing data. ML and BI analyses produced similar topology and only the ML tree was presented in Fig. 5, with ML bootstrap (LP), and PP values for each clade. The phylogenetic results showed that the two samples of the new taxon were grouped together with strong support (PP = 1.00, LP = 100%) and are closely related to Astertonglingensis with strong support (PP = 1.00, LP = 99%). According to these results, A.quanzhouensis is nested within the core Aster clade (PP = 1.00, LP = 100%) that is the redefined genus Aster in Eurasia (Li et al. 2012; Nesom 2020a, b).
Figure 5.
The phylogram of the maximum likelihood (ML) tree from the combined data (ITS, ETS and trnL-F), showing the phylogenetic position of Asterquanzhouensis. Bootstrap support values (1,000 replicates) for maximum parsimony (MP ≥ 50%, left) and Bayesian posterior probabilities (PP ≥ 0.90, right) are provided above the branches. The samples of Asterquanzhouensis are shown in bold.
Discussion
Morphological observations showed that Asterquanzhouensis has a perennial life form, lanceolate stigmatic appendage of disc florets, compressed fruits with two- or three-ribbed and uniseriate pappus (Figs 2, 3). All Aster species share these characters. In the phylogenetic tree (Fig. 5), A.quanzhouensis is deeply nested within the core Aster (Li et al. 2012). Morphological and phylogenetic analyses support that A.quanzhouensis is sister to A.tonglingensis. As mentioned above, the two species can be easily distinguished from each other (Figs 2, 3, Table 1).
Narrowly lanceolate leaves are rare in Eurasian Aster and can be found only in a few species, such as A.huangpingensis W.P.Li & Z.Li, A.dolichophyllus Y.Ling and A.tonglingensis. Our phylogenetic analyses (Fig. 5) revealed that the species with narrowly lanceolate leaves are nested in unrelated lineages of the genus Aster and are probably the result of convergent evolution. It is noteworthy to mention that they are all distributed in the same habitats confined to riparian rocks (Chen et al. 2011; Zhang et al. 2019; Li et al. 2020). The same leaf character may be related to their habitat. When the water level rises in some periods during the course of the year, these species were submerged and their narrowly lanceolate leaves may represent adaptation to water flowing in the rivers or streams.
Karyotype variation usually accompanies evolutionary divergence, a general phenomenon observed in plants and animals (Rieseberg 2001). Two populations of the Asterquanzhouensis were found with the same karyotype formula and Stebbins’ type, with only slight differences in the karyotypic indexes, which might mean that A.quanzhouensis is a young species.
Asterquanzhouensis is known only from two populations (Dehua and Yongchun counties) restricted to Quanzhou, Fujian, China, while A.tonglingensis is restricted to Mt. Tongling Natural Reserve, Wencheng county, Zhejiang (Zhang et al. 2019). These two species occupy the same ecological conditions, but are geographically separated by a distance of 400 km.
Supplementary Material
Acknowledgements
The authors are grateful to Prof. Alexander Sukhorukov, Prof. Guy Nesom and Prof. Luc Brouilet for his helpful comments. This work was supported by the National Science Foundation of China (grant no. 31960043, 31370265), Special Research Project of Jiangxi Provincial Forestry Science and Technology Innovation [grant no. (2021)22], Shanghai Municipal Administration of Forestation and City Appearances (grant number G202401) and the Open Research Fund of Guizhou Provincial Key Laboratory for Biodiversity Conservation and Utilization in the Fanjing Mountain Region [grant no. (2020)2003].
Appendix 1
Table A1.
Taxa sampled, vouchers and GenBank accessions. The newly sequenced samples are highlighted in bold.
Citation
Xiao J-W, Yan G-J, Li W-P, Tang M (2022) Aster quanzhouensis (Asteraceae), a new riparian species from eastern China. PhytoKeys 195: 93–106. https://doi.org/10.3897/phytokeys.195.82411
Funding Statement
This work was supported by the National Science Foundation of China (grant no. 31960043, 31370265), Special Research Project of Jiangxi Provincial Forestry Science and Technology Innovation [grant no. (2021)22], Shanghai Municipal Administration of Forestation and City Appearances (grant number G202401) and the Open Research Fund of Guizhou Provincial Key Laboratory for Biodiversity Conservation and Utilization in the Fanjing Mountain Region [grant no. (2020)2003].
References
- Akaike H. (1973) Information theory and an extension of the maximum likelihood principle. In: Petrov BN, Caski F. (Eds) Proceedings of the Second International Symposium on Information Theory.Akademiai, Kiado Budapest, 267–281.
- Chen YL, Brouillet L, Semple JC. (2011) Aster. In: Wu ZY, Raven PH, Hong DY. (Eds) Flora of China Vol.20–21. Science Press, Beijing & Missouri Botanical Garden Press, St. Louis, 574–632.
- Darriba D, Taboada GL, Doallo R, Posada D. (2012) jModelTest 2: More models, new heuristics and parallel computing. Nature Methods 9(8): e772. 10.1038/nmeth.2109 [DOI] [PMC free article] [PubMed]
- Edgar RC. (2004) MUSCLE: Multiple sequence alignment with high accuracy and high throughput. Nucleic Acids Research 32(5): 1792–1797. 10.1093/nar/gkh340 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Farris SJ, Kalersjo M, Kluge AG, Bult C. (1994) Testing significance of incongruence. Cladistics 10(3): 315–319. 10.1111/j.1096-0031.1994.tb00181.x [DOI] [Google Scholar]
- Huelsenbeck JP, Ronquist F. (2001) MRBAYES: Bayesian inference of phylogenetic trees. Bioinformatics (Oxford, England) 17(8): 754–755. 10.1093/bioinformatics/17.8.754 [DOI] [PubMed] [Google Scholar]
- IUCN (2022) Guidelines for Using the IUCN Red List Categories and Criteria. Version 15. Prepared by the Standards and Petitions Committee. http://www.iucnredlist.org/documents/RedListGuidelines.pdf
- Jeanmougin F, Thompson JD, Gouy M, Higgins DG, Gibson TJ. (1998) Multiple sequence alignment with Clustal X. Trends in Biochemical Sciences 23(10): 403–405. 10.1016/S0968-0004(98)01285-7 [DOI] [PubMed] [Google Scholar]
- Levan A, Fredga K, Sandberg AA. (1964) Nomenclature for centromeric position on chromosomes. Hereditas 52(2): 201–220. 10.1111/j.1601-5223.1964.tb01953.x [DOI] [Google Scholar]
- Li WP, Tang M, Yin GS, Yin Y, Yang FS, Chen SM. (2011) Extensive chromosome number variation in Asterageratoidesvar.pendulus (Asteraceae). Botanical Journal of the Linnean Society 165(4): 378–387. 10.1111/j.1095-8339.2011.01114.x [DOI] [Google Scholar]
- Li WP, Yang FS, Jivkova T, Yin GS. (2012) Phylogenetic relationships and generic delimitation of Eurasian Aster (Asteraceae: Astereae) inferred from ITS, ETS and trnL-F sequence data. Annals of Botany 109(7): 1341–1357. 10.1093/aob/mcs054 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Li Z, Yin GS, Tang M, Li WP. (2017) Asteroliganthus (Asteraceae, Astereae), a new species from western Sichuan, China, based on morphological and molecular data. Phytotaxa 326(1): 054–062. 10.11646/phytotaxa.326.1.4 [DOI] [Google Scholar]
- Li Z, Xiong YC, Liao JJ, Xiao JW, Li WP. (2020) Asterhuangpingensis (Asteraceae, Astereae), a new species from Guizhou, China. Phytotaxa 433(3): 235–244. 10.11646/phytotaxa.433.3.5 [DOI] [Google Scholar]
- Müller K, Müller J, Quandt D. (2010) PhyDE-Phylogenetic Data Editor, version 0.9971.
- Nesom GL. (2020a) Revised subtribal classification of Astereae (Asteraceae). Phytoneuron 53: 1–39. [Google Scholar]
- Nesom GL. (2020b) The genus Aster (Asteraceae) in the strictest sense. Phytoneuron 56: 1–22. [Google Scholar]
- Rieseberg LH. (2001) Chromosomal rearrangements and speciation. Trends in Ecology & Evolution 16(7): 351–358. 10.1016/S0169-5347(01)02187-5 [DOI] [PubMed] [Google Scholar]
- Stamatakis A. (2006) RAxML-VI-HPC: Maximum likelihood-based phylogenetic analyses with thousands of taxa and mixed models. Bioinformatics (Oxford, England) 22(21): 2688–2690. 10.1093/bioinformatics/btl446 [DOI] [PubMed] [Google Scholar]
- Stebbins GL. (1971) Chromosomal evolution in higher plants. Edward Arnold, London, 216 pp. [Google Scholar]
- Swofford DL. (2001) PAUP*: phylogenetic analysis using parsimony (*and other methods), version 4.0b10. Sinauer Associates, Sunderland, MA.
- Xiao JW, Liao JJ, Li WP. (2019a) Asterbrevicaulis (Asteraceae, Astereae), a new species from western Sichuan, China. Phytotaxa 399(1): 001–013. 10.11646/phytotaxa.399.1.1 [DOI] [Google Scholar]
- Xiao JW, Liao JJ, Li WP. (2019b) Asterdianchuanensis (Asteraceae, Astereae), a new species from Yunnan and Sichuan, China. Kew Bulletin 74(3): e50. 10.1007/s12225-019-9838-x [DOI]
- Xiao JW, Zhao QY, Xiong YC, Li WP. (2020) Asterchuanshanensis (Asteraceae), a New Species from Shanxi and Sichuan, China. Annales Botanici Fennici 57(4–6): 341–350. 10.5735/085.057.0417 [DOI] [Google Scholar]
- Xiao JW, Zhao QY, Xie D, Tang ZB, Li WP. (2021) Astersanqingshanica (Asteraceae, Astereae), a new species from Jiangxi, China. Nordic Journal of Botany 39(4): e02990. 10.1111/njb.02990 [DOI]
- Xiong YC, Li Z, Xiao JW, Li WP. (2019) Astersaxicola sp. nov. (Asteraceae, Astereae), a new species from Guizhou, China: Evidence from morphological, molecular and cytological studies. Nordic Journal of Botany 37(10): e02364. 10.1111/njb.02364 [DOI]
- Zhang GJ, Hu HH, Zhang CF, Tian XJ, Peng H, Gao TG. (2015) Inaccessible biodiversity on limestone cliffs: Astertianmenshanensis (Asteraceae), a new critically endangered species from China. PLoS ONE 10(8): 1–16. 10.1371/journal.pone.0134895 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Zhang GJ, Hu HH, Gao TG, Gilbert MG, Jin XF. (2019) Convergent origin of the narrowly lanceolate leaf in the genus Aster-with special reference to an unexpected discovery of a new Aster species from East China. PeerJ 7: e6288. 10.7717/peerj.6288 [DOI] [PMC free article] [PubMed]
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