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1 Phytotaxa 236 (2): ISSN (print edition) Copyright 2015 Magnolia Press Article PHYTOTAXA ISSN (online edition) Youngia purpimea (Asteraceae), a new species from Sichuan, China YU-LAN PENG 1*, WEN-BIN JU 1, XIN-FEN GAO 1* & YUN-DONG GAO 1 1 Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration Biodiversity Conservation and Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, P.O. Box 416, Chengdu, Sichuan , China * s: pengyl@cib.ac.cn, xfgao@cib.ac.cn Abstract Youngia purpimea, a new species from southern Sichuan, China, is described and illustrated. This species is morphologically most similar to Y. szechuanica and Y. zhenyiana by having capitula with five yellow florets, but differs from the latter two by having leathery and undivided caudical leaves being glabrous on both surfaces and purplish red abaxially, leaf margins sparsely dentate, and also by brown pappus. Key words: Compositae, Crepidinae Introduction Youngia Cassini (1831: 88) is a genus of ca. 30 species in E. Asia (Babcock & Stebbins 1937, Deng et al. 2014), with 28 species (22 endemic) in China (Shih & Kilian 2011). China undoubtedly has the highest diversity of the genus. Most species of Youngia in China have narrow distributions, and further discoveries of new species is expected as more botanical explorations proceed in this country. We carried out botanical expeditions in the Huagaoxi Natural Reserve, Sichuan Province, China, from March 2012 to March 2014, for the project on the biodiversity survey at this area. In the Huagaoxi Natural Reserve, we collected some interesting new plants of Youngia. After a careful examination of the morphology, we determined that they represent an undescribed new species. Here we describe it as Youngia purpimea. Taxonomy Youngia purpimea Y.L. Peng, W.B. Ju, X.F. Gao & Y.D. Gao, sp. nov. (Figs. 1 & 2) Diagnosis: The new species is most similar to Youngia szechuanica (Söderberg (1934: 362) Hu (1969: 37) [= Y. scaposa Babcock & Stebbins (1937: 45), nom. illeg., according to Art of the Melbourne Code (McNeill et al. 2012)], but is distinct by having leathery undivided caudical leaves being glabrous on both surfaces and purplish red abaxially, leaf margins sparsely dentate, and also by brown pappus (Figs. 1 & 2). Type: CHINA. Sichuan Province: Xuyong County, Huagaoxi Nature Reserve, Shuiwei Town, Guangmu Village, on the wet rock near waterfall, 650 m, 5 July 2013, Xin-Fen Gao, Yung-Dong Gao & Wen-Bin Ju, HGX11571 (holotype & isotypes, CDBI). Perennial herb, rhizomatous, height cm, with leaves basally crowded on a short apically brown-woolly caudex, stems erect, solitary, almost leafless, smooth and glabrous. Caudical leaves 5 6, lamina narrowly ovate, 2 6 cm wide, 6 16 cm long, margin sparsely and shallowly sinuate-dentate with long-acuminate teeth, apex acuminate, base attenuate into a petiole, 4 15 cm long. Cauline leaves few, supporting the synflorescence branches, linear or bractlike. All leaves thick-textured, mostly leathery, both surfaces glabrous, abaxially purplish red. Capitula numerous, in a paniculiform-corymbiform synflorescence. Capitulum with five flowers. Involucre with phyllaries in 3 4 series, outermost phyllaries 1.5 mm long, 1 mm wide, apex acute; inner phyllaries 7 8 mm long, 1.5 mm wide. Flowers Accepted by Alexander Sennikov: 6 Nov. 2015; published: 27 Nov

2 yellow, corolla tube 2 to 3 mm long, pubescent with short hairs, ligule 3 4 mm long, 2 mm wide, anther tube 3 mm long, style branches mm long. Immature achenes yellow brown, ribs unequal, flattened, length 1 2 mm. Pappus 4 5 mm long, brown, 2-seriate. Etymology: Purp- refers to the abaxially purplish red leaves of the new species; -imea is an artificial ending. FIGURE 1. Line drawing of Youngia purpimea Y.L. Peng, W.B. Ju, X.F. Gao & Y.D. Gao. A. Floret. B. Achene. C. Pappus. D. Ligule of a floret. E. Anther. F. Immature achene enlarged. G. Type image. H. Involucral bracts (A F drawn by Y.L. Peng based on the holotype). 192 Phytotaxa 236 (2) 2015 Magnolia Press PENG ET AL.

3 FIGURE 2. Photographs of Youngia purpimea Y.L. Peng, W.B. Ju, X.F. Gao & Y.D. Gao. A. Habitat in moist slope. B. Capitula of Youngia purpimea. C. Florets. D. Abaxial view of leaves. E. Brown-woolly caudex. (Photos by W.B. Ju from Huagaoxi Nature Reserve, Xuyong County, Longfeng Town). Distribution and habitat: The new species is known only from the type locality and the adjacent Longfeng Town in Xuyong County of Sichuan Province, China, at elevations between m, growing on wet rock slopes. Youngia purpimea (Asteraceae) Phytotaxa 236 (2) 2015 Magnolia Press 193

4 Additional material examined (paratype): CHINA. Sichuan Province. Huagaoxi Nature Reserve, Xuyong County, Longfeng Town, elev. 500 m, N, E, 9 May 2014, W.B. Ju, L. Zhang, X.M. Zhou, L. Zhang & Y.L. Peng 1601 (CDBI). Phenology: Flowering and fruiting from May to July. Discussion: Morphologically, Youngia purpimea is most similar to Y. szechuanica in having 5-flowered capitula and few bract-like cauline leaves and brown-woolly short caudex. However, Y. purpimea is different from Y. szechuanica by having leathery undivided caudical leaves with long petioles, leaf margins entire or sparsely dentate, and brown pappus. Youngia purpimea is also close to Y. zhenyiana Deng et al. (2014: 265) in having 5-flowered capitula, but the latter has soft, large, lyrately pinnatisect cauline leaves. Youngia purpimea is unique by having the combination of its mostly leathery leaves, glabrous on both surfaces, purplish red abaxially (Fig. 2C), long petioles, and brown-woolly short caudex (Fig. 2E), five yellow flowers (Fig. 1A, B & Fig. 2C), and brown pappus. The delimitation of Youngia is sometimes confused with Crepidiastrum Nakai (1920: 140), Crepis Linnaeus (1753: 805), Ixeris Nakai (1920: 155), Faberia Hemsley (1888: 479), Ixeridium )Gray 1859: 397) Tzvelev (1964: 388), and Prenanthes Linnaeus (1753: 797) s.l. [incl. Nabalus Cassini (1825: 94)], because of the reticulate evolution in tribe Cichorieae (Peng et al. 2014). We also compared Y. purpimea with the species of those similar genera. This new species looks like Ixeridium laevigatum Blume (1826: 886) Pak & Kawano (1992: 45) at the first glance in having similar leaves and five ray flowers and brown pappus, but this species can be distinguished from Ixeridium by having flat unbeaked achenes, which only appear in Youngia. Leathery purplish red leaves of Y. purpimea are reminiscent of the leaves of Faberia nanchuanensis Shih (1995: 195), but the former species has much smaller flower-heads and unequal ribs on achenes, and broader leaves (Fig. 2B). The molecular phylogenetic analysis based on nuclear ITS region and three plastid genes (Y.L. Peng et al. unpubl. data) supports the position of Youngia purpimea as a member of Youngia and resolves it as sister to Y. szechuanica. It should be the second member of Y. sect. Hieraciella Babcock et Stebbins (1937: 25), nom. inval. Possibly, this species represents a young lineage diverged from its ancestor Y. sect. Youngia and is endemic to the Huagaoxi Nature Reserve in southern Sichuan (Fig. 2A). Acknowledgements This study was partially supported by National Natural Science Foundation (grant No , ), Knowledge innovation project of Chinese Academy of Sciences (grant No. Y1B ), 12th Five-Year Plan Project of the National Science and Technology of China (grant No. 2011BAC09B ) Sichuan Province Science and Technology Project (grant No. 2013NZ0037) and Biodiversity Survey Project in Huagaoxi Nature Reserve. We are indebted to two anonymous reviewers and Dr. Alexander Sennikov for their helpful suggestions on the manuscript. References Babcock, E.B. & Stebbins Jr., G.L. (1937) The genus Youngia. (Carnegie Institution of Washington Publication 484.) Carnegie Institution of Washington, Washington, pp Blume, C.L. (1826) Bijdragen tot de flora van Nederlandsch Indië [part 15]. Ter Lands Drukkerij, Batavia, pp Cassini, H. de (1825) Nabalus. In: Cuvier, F. (Ed.) Dictionnaire des Sciences Naturelles 34. Le Normant, Paris, pp Cassini, H. de (1831) Descriptions de quelques Synanthérées de l île Maurice. Annales des Sciences Naturelles, ser. 1 23: Deng, T., Zhang, J.-W., Zhu, X.-X., Zhang, D.-G., Nie, Z.-L. & Sun, H. (2014) Youngia zhengyiana (Asteraceae, Crepidinae), a new species from south China, with notes on the systematics of Youngia inferred from morphology and nrits phylogeny. Phytotaxa 170 (4): Gray, A. (1859) Diagnostic characters of new species of phanogamous plants, collected in Japan by Charles Wright, Botanist of the U. S. North Pacific Exploring Expedition. With observations upon the relations of the Japanese flora to that of North America, and of other parts of the Northern Temperate Zone. Memoirs of the American Academy of Arts and Sciences 6 ( 2) : Hemsley, W. (1888) An enumeration of all the plants known from China Proper, Formosa, Hainan, Corea, the Luchu Archipelago, and the Island of Hongkong, together with their distribution and synonymy. Part VI. Journal of the Linnean Society, Botany 23 (157): Phytotaxa 236 (2) 2015 Magnolia Press PENG ET AL.

5 Hu, S.-Y. (1969) The Compositae of China (IX). Quarterly Journal of the Taiwan Museum 22: Linnaeus, C. (1753) Species plantarum. L. Salvuis, Stockholm, 1200 pp. McNeill, J., Barrie, F.R., Buck, W.R., Demoulin, V., Greuter, W., Hawksworth, D.L., Herendeen, P.S., Knapp, S., Marhold, K., Prado, J., Prud homme van Reine, W.F., Smith, G.F., Wiersema, J.H. & Turland, N.J. (Eds.) (2012) International Code of Nomenclature for algae, fungi, and plants (Melbourne Code) adopted by the Eighteenth International Botanical Congress Melbourne, Australia, July (Regnum Vegetabile 154.) Koeltz Scientific Books, Königstein, XXX pp. Nakai, T. (1920) Notulae ad plantas Japoniae et Koreae, XXIII. Botanical Magazine (Tokyo) 34: Pak, J.H. & Kawano, S. (1992) Biosystematic studies on the genus Ixeris and its allied genera (Compositae: Lactuceae) IV. Taxonomic treatments and nomenclature. Memoirs of the Faculty of Science Kyoto University Series of Biology 15: Peng, Y.-L., Zhang, Y., Gao, X.-F., Tong, L.-J., Li, L., Li, R.-Y., Zhu, Z.-M. & Xian, J.-R. (2014) A phylogenetic analysis and new delimitation of Crepidiastrum (Asteraceae, tribe Cichorieae). Phytotaxa 159 (4): Shih, C. (1995) New species of the Chinese Compositae. Acta Phytotaxonomica Sinica 33: Shih, C. & Kilian, N. (2011) Youngia. In: Wu, Z.-Y., Raven, P.H. & Hong, D.-Y. (Eds.) Flora of China Science Press, Beijing & Missouri Botanical Garden Press, St. Louis, pp Söderberg, E.S. (1934) Über die Chromosomenzahl von Crepis scaposa R.E.Fr. Svensk Botanisk Tidskrift 28: Tzvelev, N.N. (1964) Ixeridium (A.Gray) Tzvel. In: Bobrov, E.G. & Tzvelev, N.N. (Eds.) Flora of the USSR 29. Academy of Sciences of the USSR, Moscow & Leningrad, pp Youngia purpimea (Asteraceae) Phytotaxa 236 (2) 2015 Magnolia Press 195