Taiwania, 51(1): 46-49, 2006 Eleutheranthera ruderalis (Swartz) Sch.-Bip. (Asteraceae), a Newly Naturalized Plant in Taiwan－ Sheng-Zehn Yang(1, 2) and Gaung-Pu Hsieh(1) (Manuscript received 5 August, 2005; accepted 10 November, 2005) ABSTRACT: A new record of a naturalized plant of Asteraceae, Eleutheranthera ruderalis (Swartz) Sch.-Bip. was found in southern Taiwan. Eleutheranthera Poit. ex Bosc is also a new genus to the Flora of Taiwan. E. ruderalis can be easily distinguished from Synedrella nodiflora (L.) Gaertn. by its head only with disc florets, stamens free, pappus absent, achenes pubescent and angled. A taxonomic description, line drawing, photographs, and a map showing its distribution on this island are provided. KEY WORDS: Asteraceae, Eleutheranthera ruderalis, Naturalized, Taiwan, Taxonomy. INTRODUCTION TAXONOMIC TREATMENT Asteraceae is one of the largest families of Eleutheranthera Poit. ex Bosc, Nouv. Dict. Hist. flowering plants, comprising about 1,535 genera and Nat. ed. 1. 7: 498. 1803. 23,000 species. Eighty-four genera and 241 species of Asteraceae, including 20 infraspecific taxa were Erect branching annual herbs. Leaves opposite, found in Taiwan (Peng et al., 1998). Asteraceae is the simple, petiole. Head small, terminal or axils of largest dicotyledonous and one of the notorious upper leaves, homogamous, few flowers, flower contributors to the naturalized flora of the world monoecious. Involucre campanulate; bracts 5-10, (Pyšek et al., 2004; Wu and Wang, 2005). It has been foliaceous, 1-2 seriate, of unequal length, florets the major contributor to the naturalized flora of embracing, keeled. Ray florets often absent, when Taiwan (Hsieh, 2002; Wu et al., 2004). In 1996, we present few, ligulate. Disc flowers tubular, narrowly collected an unknown species of Asteraceae in campanulate, 5-lobed; anther free or very loosely southern Taiwan. The appearance of this plant is cohering, base sagittate, apex truncate; style similar to Synedrella nodiflora (L.) Gaertn. that we branches linear, acuminate, covered with minute misidentified it as Synedrella nodiflora for many hairs at the apex. Receptacle convex; paleaceous, years. concave. Achenes narrowly obovoid, somewhat Compared to the descriptions of Flora of Java compressed, 3-4 angular, abruptly narrowed to a (Backer and Bakhuizen, 1963) and Flora of Ceylon small cylindrical protuberance at the apex. Pappus (Dassanayake, 1987), all the characters of this plant absent. are similar to those of genus Eleutheranthera Poit. ex Bosc. Eleutheranthera is a monotypic genus of Eleutheranthera ruderalis (Swartz) Sch.-Bip., Bot. Asteraceae native to Tropical America and Zeit. 24: 165, 239. 1866; Backer & Bakh. Fl. naturalized in Java, Ceylon, Papua New Guinea and Java 2: 407, 1965. Fiji (Dassanayake, 1987). We believe that this 離藥金藥箭(新擬) Figs. 1 & 2 species is a new record and the scientific name is Eleutheranthera ruderalis (Swartz) Sch.-Bip. It also Melampodium ruderale Swartz, Fl. Ind. Occ. 3: 1372. 1806. represents the first generic record of Eleutheranthera in Taiwan. In this paper we describe the taxonomy, Erect branching annual herbs, stems thickened on morphology of the genus and species, and provide a the nodes, glabrous or hairy, up to about 60-75 cm line drawing, distribution map, and photographs of height. Leaves ovate or ovate-oblong, trinerved, the plant in its natural habitat. blade 1.5-7 cm long, 1-3 cm wide, base round and ___________________________________________ shortly attenuate, apex obtuse or acute, thinly 1. Department of Forestry, National Pingtung University of long-pilose on both surfaces; margin shallowly Science and Technology, 1, Shuehfu Rd., Neipu, Pintung 912, Taiwan. crenate or serrate; petiole 0.5-1.5 cm long. Heads 2.Corresponding author. Tel: 886-8-7703202 ext. 7154; Email: solitary or 2-4 in each axils, peduncles 0.5-1 cm [email protected] long, erect at first, cernuous in fruit; involucres March, 2006 Yang & Hsieh: Eleutheranthera ruderalis 47 Fig. 1. Eleutheranthera ruderalis (Swartz) Sch.-Bip. A: Habit. B: Stamens. C: Style branches. D: Disc floret. E: Achene. F: Involucres of bracteole. G.: Head. accrescent, bracts 5-8 in 1-2 series, receptacle oblong-elliptic, acuminate, scarious, 3-4 elliptic-lanceolate, obtuse or acute, spreading and mm long, ciliate at the margins; anthers black, base foliaceous, 4-6 mm long, 1-1.5 mm broad, green, sagittate, apex truncate; style branches yellow, keeled, long-pilose, bracteole membranous, oblong, linear, apex covered with minute hairs. Achenes apex long-pilose; ray florets often absent; disc 2.5-3 mm long, verrucose on the 4-angles, minutely florets yellow, 9-11, corollas tubular, 2-2.5 mm long, white puberulous near the apex, pappus wanting. lobes 0.5 mm long, papillose; ovary 2 mm long; 48 TAIWANIA Vol. 51, No. 1. A B C Fig. 2. A: Eleutheranthera ruderalis growing along the roadside. B: The morphology of an inflorescence with 9-11 disc florets. C: Achene verrucose on the 4-angles. (Scale = 0.5 mm). Habitat: Eleutheranthera ruderalis is fairly common along roadsides, on waste lands, and on cultivated ground, often associated with Ageratum houstonianum Mill., Bidens pilosa L. var. radiata Sch. Bip. (Asteraceae), Cardamine flexuosa With. (Cruciferae), Cleome rutidosperma DC. (Capparaceae), Panicum maximum Jacq. (Poaceae), and Pouzolzia zeylanica (L.) Benn. (Urticaceae). Flowering and fruiting are possible throughout the year. Specimen examined: S. Z. Yang, 28413 (PPI), 29 Feb. 1996, Wugoushuei, Pingtung county. S. Z. Yang, 28856 (PPI), 16 Apr. 2000; sugar factory, Pingtung city. G. P. Hsieh, 1967 (PPI), 15 Apr. 2005, Tungpin village, Pingtung county. DISCUSSION Dassanayake (1987) reported that Eleutheranthera ruderalis grows in much the same situations as, and closely resembers, Synedrella nodiflora. However, after the disc flowers being Fig. 3. Distribution of Eleutheranthera ruderalis in southern Taiwan. 1: Pintung city. 2: NeipuTungpin village. 3: Wugoushuei. dissected, it can be distinguished from S. nodiflora by its head with disc florets only, stamens free, pappus absent, achenes pubescent and angled. E. ACKNOWLEDGEMENTS ruderalis can establish itself and increase population number gradually without human intervention. As a We greatly appreciate Dr. Peng, Ching-I for result E. ruderalis has abundantly naturalized in helpful comments on this issue, Laio, Jia-Hong for exposed, flat areas (author’s observation). This is in assisting with digital works and Liao, Chun-Kuei for accordance with the definition of Pyšek et al. (2004) excellent line drawings. We also appreciate two and Wu and Wang (2005) as a naturalized plant. reviewers for giving many suggestions. As we have mentioned previously, Eleutheranthera is a monotypic genus naturalized in LITERATURE CITED Java, Ceylon, Papua New Guinea and Fiji, it is clear that Taiwan is a new naturalized region. Though Backer, C. A. and C. R. Bakhuizen van den Brink. there is no clue about when and how the species 1963. Flora of Java. 2: 407. N. V. P. Noordhoff immigrated to Taiwan, we believe that E. ruderalis Groningen, Netherlands. pp. 641. will be found not only in south but also other regions of Taiwan in the near future. (Fig. 3) March, 2006 Yang & Hsieh: Eleutheranthera ruderalis 49 Dassanayake, M. D. 1987. A Revised Handbook to Pyšek, P., D. M. Richardson, M. Rejmánek, G. L. the Flora of Ceylon. 1: 217-281. Amerind Webster, M. Williamson and J. Kirschner. 2004. publishing Co. Pvt. Ltd. New Delhi, India. pp. Alien plants in checklists and floras: Toward 508. better communication between taxonomists and Hsieh, C.-F. 2002. Composition, endemism and ecologists. Taxon 53: 121-143. phytogeographical affinities of the Taiwan Wu, S.-H., C.-F. Hsieh and M. Rejmánek. 2004. Flora. Taiwania 47: 298-310. Catalogue of the naturalized flora of Taiwan. Peng, C.-I., K.-F. Chung and H.-L. Li. 1998. Taiwania 49: 16-31. Compositae. In: Huang, T.-C. et al. (eds.), Flora Wu, S.-H. and H.-H. Wang. 2005. Potential of Taiwan, 2nd ed. 4: 1051-1062. Editorial Asteraceae invaders in Taiwan: Insights from Committee, Department of Botany, National flora and herbarium records of casual and Taiwan University, Taipei, Taiwan. pp. 1217. naturalized alien species. Taiwania 50: 62-70. 臺灣新歸化菊科植物－離藥金腰箭 楊勝任(1,2)、謝光普(1) (收稿日期：2005年8月5日；接受日期：2005年11月10日) 摘 要 本文報導臺灣南部新歸化菊科植物－離藥金腰箭 (Eleutheranthera ruderalis (Swartz) Sch.-Bip.)，離藥金腰箭屬 (Eleutheranthera Poit. ex Bosc) 同時也是臺灣的新紀 錄屬。本種於1996年初次採集於南臺灣，雖與金腰箭 (Synedrella nodiflora (L.) Gaertn.) 很相似，但由本種頭狀花序僅具管狀花、雄蕊分離、無冠毛、瘦果有毛且具稜角可加以 區別。本文提供該種植物的分類性狀描述、手繪圖和在臺灣的分布圖。 關鍵詞：菊科、離藥金腰箭、歸化、臺灣、分類學。 __________________________________________________________________________________________ 1. 國立屏東科技大學森林系，912屏東縣內埔鄉學府路1號，臺灣。 2. 通信作者。Tel: 886-8-7703202 ext. 7154; Email: [email protected]