J. Jpn. Bot. 91 Suppl.: 112–119 (2016)

Melanoseris henryi (-) Revisited: A New Record of and Species from the Flora of Lao PDR with Its Systematic Position

a b a,c Jian-Wen Zhang , Norbert Kilian , Tao Deng , d a, Onevilay Souliya and Hang Sun *

aKey Laboratory for Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, Yunnan, P. R. CHINA; bBotanischer Garten und Botanischer Museum Berlin-Dahlem, Freie Universität, 14195 Berlin, GERMANY; cUniversity of Chinese Academy of Sciences, Beijing 100039, P. R. CHINA; dMinistry of Health, Institute of Traditional Medicine, Vientiane, LAOS *Corresponding author: [email protected]

(Accepted on February 2, 2016)

Melanoseris henryi (Dunn) N. Kilian (Asteraceae-Cichorieae) is reported for the first time for the Bolaven Plateau of southern Laos (Champasak province). Hitherto this rare species was only known from the type collection made at Pu’er, in southern Yunnan, China, at the end of the 19th century, where it has not been recollected since. This is also the first record for the genus Melanoseris from Laos. The phylogenetic analysis based on DNA sequences of nuclear ribosomal internal transcribed spacer (nrITS) confirms the placement in the Flora of China of this species with 3–6-flowered capitula in the revived Melanoseris. Within the Melanoseris lineage, M. henryi clusters into a clade together with Melanoseris atropurpurea, M. likiangensis, and M. macrantha, all species with many-flowered capitula, which is sister to a clade of two species with 3-flowered capitula, M. tenuis and M. graciliflora. In our molecular phylogeny statistical support of the relationships within the Melanoseris lineage is, however, weak. A description and illustrations of Melanoseris henryi, which is also rare in southern Laos, are provided. The presence of Melanoseris in southern Laos provides new clues to illuminate the history of the geographical distribution and the evolution of this lineage, and even the relationships between the floras of southwestern China and southern Laos.

Key words: Asteraceae, Bolaven Plateau, Cichorieae, flora of Laos, Lactucinae, Melanoseris, ITS, new record, .

The genus Melanoseris Decne. (Asteraceae- In the recent molecular phylogeny, the bulk Cichorieae-Lactucinae) was established by of species formerly assigned to Chaetoseris Decaisne in 1843 based on M. lessertiana Shih, including the type of that name, or to the (DC.) Decne., and the genus is one of the genus Stenoseris Shih, as well as a number of oldest described in subtribe Lactucinae but has species formerly placed in Wallr., never found recognition until it was revived L., Mulgedium Cass., L., in the Flora of China (Shih and Kilian 2011). and even Syncalathium souliei (Franch.) Y.

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Fig. 1. Living of Melanoseris henryi (Dunn) N. Kilian. A. Habitat. B. Habit. C. Florets with reflexed corolla-lobes. D. Achenes with paler beaks. Bolaven Plateau, Champasak prov., southern Laos, on 18 November 2012. 114 The Journal of Japanese Botany Vol. 91 Centennial Memorial Issue

Ling, are members of a sizable Melanoseris has hitherto only been known from the type clade (Kilian et al. 2009–, Shih and Kilian 2011, collection made at Pu’er (Puerh), in southern Wang et al. 2013). The systematic position of Yunnan, China, at the end of the 19th century Parasyncalathium souliei (Franch.) J. W. Zhang, by the Irish Sinologist and plant collector Boufford & H. Sun (≡ Syncalathium souliei Augustine Henry. In spite of various attempts, it Franch.), however, is so far not settled, allowing has not been recollected from the type locality alternative classifications, either as a member of or elsewhere in southern Yunnan. Its systematic Melanoseris as M. souliei (Franch.) N. Kilian position has not been assessed so far in a (Shih and Kilian 2011) or in a separate genus of molecular phylogeny. its own (Zhang et al. 2011a). During a field trip to investigate the The Melanoseris lineage, as revealed by biodiversity of the great Mekong river in the Wang et al. (2013) contains species with few- Bolaven Plateau of southern Laos (Champasak flowered capitula as well as those with the province), one species of Cichorieae with 5 largest number of florets per capitulum in the purplish florets in a capitulum was found and subtribe Lactucinae. The species with few- collected in 2012 by Sun Hang and his group. flowered capitula, achenes with thickened lateral It was recognised to be similar to M. henryi ribs and a pappus with an outer ring of minute sensu Flora of China (Shih and Kilian 2011), hairs were previously united in Stenoseris by but situated more than 1000 km distant from Shih (1991, 1997). All the species of Stenoseris the southernmost occurrences (Yunnan, China) have 3 florets, apart from S. auriculiformis with of that genus and species (Shih 1997, Shih 5 florets (Shih 1995, 1997), which is distributed and Kilian 2011). The species was not found only in North China (Gansu, Ningxia, Inner or collected during two further field trips to Mongolia; Zhu et al. 2006a), beyond the northern and Central Laos in 2013. distribution range of the other Stenoseris species The aim of the present work is to assess confined to the Sino-Himalayan area.Stenoseris, the identity of the Laos plant with Melanoseris however, was revealed by Wang et al. (2013) to henryi, to describe and illustrate it, and to be an artificial polyphyletic assemblage, with assess its systematic position by a molecular the bulk of the species with three florets being phylogenetic analysis. nested in Melanoseris. The same holds true for Shih’s genus Chaetoseris (Shih 1991, 1997), Material and Methods which united those species having achenes Morphological assessment with thickened lateral ribs and an acuminate or Morphology of the Laos specimens beaked apex, and a pappus with an outer ring of (Sun Hang 12570) was examined and the minute hairs. Most of its species, including those specimens were identified with the help of with the largest number of flowers per capitulum Flora of China (Shih and Kilian 2011), the in the subtribe Lactucinae, are nested in the digital images of the holotype of Lactuca Melanoseris lineage (Wang et al. 2013). henryi Dunn at the Kew herbarium (A. Lactuca henryi Dunn with its slender Henry 13494) (http://apps.kew.org/herbcat/ involucres with four or five florets and long- getImage.do?imageBarcode=K000808081) beaked achenes, which was omitted from FRPS and the isotypes at the herbaria MO and NY (Shih 1997) and Flora Yunnanica (Zhuang (accessed via Tropicos (http://www.tropicos.org/ 2004), was placed in the Flora of China (Shih image/100125801 on 8 May 2014) and JSTOR and Kilian 2011) on morphological grounds Global Plants (http://plants.jstor.org/) as well as into Melanoseris as M. henryi (Dunn) N. Kilian. the protologue of Lactuca henryi (Dunn 1903). It is an apparently very rare species, which December 2016 Zhang et al.: Melanoseris henryi in Laos 115

DNA sequencing and molecular analyses Prior to the model-based ML and BI We sampled the Laos specimen for approaches, the best fit model of nucleotide molecular analyses. The voucher information substitutions for the ITS sequence data was and GenBank accession number of the sampled explored with the hierarchical likelihood species are provided in the Appendix 1. ratio test as implemented in MrModeltest Soroseris erysimoides (Hand.-Mazz.) C. Shih 2.3 (Nylander 2004), which suggested the from Crepidinae was chosen as the outgroup generalized time reversible model (GTR + I + of our Lactuc