Microsoft Word - 06. 43-13 Elatostema biopositum OK 4.doc Bangladesh J. Plant Taxon. 20(2): 179-183, 2013 (December) © 2013 Bangladesh Association of Plant Taxonomists ELATOSTEMA BIOPPOSITUM (URTICACEAE), A NEW SPECIES FROM GUANGXI, CHINA LIN-DONG DUAN AND YUN LIN1 Shaoyang University, Shaoyang 422004, Hunan, People’s Republic of China Keywords: Elatostema bioppositum; New species; Urticaceae; China. Abstract A new species of Elatostema J. R. Forst. & G. Forst. (Urticaceae), E. bioppositum L. D. Duan & Y. Lin, is described and illustrated from Guangxi, China. This species was found growing in evergreen broad-leaved forests in limestone hills at altitudes of 410-550 m. The new species is related to E. oppositum Q. Lin & Y. M. Shui, but differs from the latter by stipule linear, lanceolate-linear or lanceolate, 12-25 mm long, 2.0-4.5 mm wide; leaf blade green after drying; male inflorescence 15-30 mm in diameter and peduncle 2-3 mm long; and female inflorescence 7-15 mm in diameter. Introduction The genus Elatostema J. R. Forster & G. Forster, as one of the largest genera in the family Urticaceae, consists of c. 500 species and is distributed in tropical and subtropical regions of Africa, Asia and Oceania. Southern and south-western China is one centre of distribution for Elatostema and about 240 species of Elastostema have been recorded from China (Wu et al., 2012). After a series of taxonomic studies on Elatostema have been published (Duan and Lin, 2003, 2007, 2010; Duan et al., 2006a, 2006b, 2011; Lin and Duan, 2002a, 2002b, 2003, 2008), we have examined some specimens of Elatostema from China and its adjacent area, and carried out field studies in China (Guangdong, Guangxi, Guizhou, Hubei, Hunan, Sichuan, Yunnan) and Vietnam. During an expedition in Longzhou County, southwest Guangxi Zhuangzu Zizhiqu, southwest China from April to June 2011, and July 2012, a previously unknown species was collected in evergreen broad-leaved forests in limestone hills at altitudes of 410-550 m, latitude 22º 39' N, longitude 106º 49' E. After critical examination of the specimens and carefully consulting relevant literatures (Wang, 1995; Lin and Duan, 2002a,b, 2003, 2008; Duan and Lin, 2003, 2007, 2010; Lin et al., 2003; Duan et al., 2006a,b; Bi et al., 2001; Wu et al., 2012; Wei et al., 2013), they been identified as a new species, Elatostema bioppositum sp. nov. The new species is described and illustrated here. Elatostema bioppositum L. D. Duan & Y. Lin, sp. nov. (Figs 1-3). Diagnosis: Elatostema bioppositum is morphologically similar to E. oppositum Q. Lin & Y. M. Shui, but differs in stipule, leaf blade colour after drying, male receptacle size and peduncle length, and female inflorescence size as summarized in Table 1. Type: China. Guangxi Zhuangzu Zizhiqu: Longzhou County, Jinlong town, 410-550 m, 1 April 2011, ♂, L. D. Duan 5241 (Holotype: PE; Isotypes: HUFD (Herbarium, Hunan Food and Drug Vocational College, Hunan, China), HUSY (Herbarium, Shaoyang University, Hunan, China), K, MO, P, PE); the same locality, 3 April 2011, ♂, L.D. Duan (Paratypes: HUSY, PE), 5212 (Paratypes: HUSY, PE); the same locality, 25 May 2011, ♀, L.D. Duan 5253 (Paratypes: HUSY, PE), 5254 (Paratypes: HUSY, PE); the same locality, 3 June 2011, ♀, L.D. Duan 5256 1Hunan Food and Drug Vocational College, Changsha 410014, Hunan, People’s Republic of China. Corresponding author. Email: leoliny@foxmail.com 180 DUAN AND LIN (Paratypes: HUSY, PE), 5258 (Paratypes: HUSY, PE); the same locality, 4 June 2011, ♀, L.D. Duan 5260 (Paratypes: HUSY, PE), 5262 (Paratypes: HUSY, PE); the same locality, 26 July 2012, ♀, L.D. Duan & Y. Lin 25 (Paratypes: BM, HUFD, HUSY, L, PE), 26 (Paratypes: HUFD, HUSY, PE). Vernacular name: Shuangduisheng louticao. Perennial herbs, tufted, tap-rooted, dioecious, 40-80 cm tall, glabrous. Stems fleshy, erect or ascending, simple, 0.3-2.0 cm in diameter, longitudinally striate and brown furfuraceous. Leaves alternate; nanophyll absent; stipules 2, herbaceous, linear, lanceolate-linear or lanceolate, 12-25 mm long, 2.0-4.5 mm wide, with cystoliths linear, 0.2-0.5 mm long, deciduous; petiole 2-10 mm Fig. 1. Elatostema bioppositum L. D. Duan & Yun Lin, sp. nov. (L. D. Duan 5212, PE). (A) male habit, (B) portion of male flowering stem (L. D. Duan 5241, PE), (C) portion of fruiting stem (L. D. Duan 5253, PE), (D) achene (L. D. Duan 5253, PE). ELATOSTEMA BIOPPOSITUM, A NEW SPECIES FROM CHINA 181 long; leaf blade obliquely oblong, (35-) 70-195 mm long, (11-) 30-115 mm wide, glabrous, fleshy, or chartaceous and green after drying, venation pinnate, major basal lateral (secondary) veins absent, with cystoliths conspicuous, linear, 0.2-0.6 mm long, dense, random on both surfaces; base with broader half rounded or auriculate, narrower half cuneate; margin dentate or crenate, lower broader-half basal ≤1/3 entire and narrower-half basal ≤2/3 entire; apex acute or acuminate, acumen entire. Male inflorescence or female inflorescence opposite each other at the same stem Figs 2-3. 2. Elatostema bioppositum sp. nov. Habitat of male plant (L. D. Duan 5241). (A) male branches, (B) male inflorescences when young, (C) vegetative branches. 3. Elatostema bioppositum sp. nov. Habitat of female plant (L. D. Duan 5262). (A) female branches, (B) female inflorescences. node with the node either bearing a leaf or a bract and without a leaf, one male inflorescence or one female inflorescence opposes at the leaf base, with the second one at the bract base, or both found at bract bases when the stem node leafless; bracts on the node herbaceous, glabrous, 182 DUAN AND LIN lanceolate to narrowly ovate, 6-20 mm long, 3-6 mm wide, deciduous. Male inflorescence solitary, simple, 15-30 mm in diameter; peduncle glabrous, 2-3 mm long; receptacle pyriform when young, dehiscent, nearly butterfly-like when mature, 15-30 mm in diameter, with cystoliths; involucral bracts obscure; bracteoles numerous, equal, dense, linear, 1.5-2.0 mm long. Male flowers 4- merous; perianth lobes yellowish or white, ovate-elliptic, 2.2-2.5 mm long; stamens 4; pistil rudimentary, very small. Female inflorescence solitary, nearly orbicular, mostly 7-15 mm in diameter, receptacle nearly orbicular, 5-10 mm in diameter, with cystoliths; involucral bracts obscure; bracteoles numerous, very small, subulate, c. 1 mm long. Achenes ellipsoidal, 0.7-0.8 mm long, c. 4-ribbed. Phenology: Flowering from April to May and fruiting from June to July. Etymology: The epithet ‘bioppositum’ refers to male inflorescence or female inflorescence opposite to each other at the same stem node with the node either bearing a leaf or without a leaf, one male inflorescence or one female inflorescence opposes at the leaf base, with the second one at bract base, or both found at bract bases when the stem node is leafless. Habitat: It grows only in evergreen broad-leaved forests in limestone hills at altitudes of 410- 550 m, comprising c. 900 individuals growing in more than ten populations within a nature reserve. Distribution: Elatostema bioppositum is only known from its type locality, Gaoshan village, Jinlong town, Longzhou County, southwest Guangxi Zhuangzu Zizhiqu, South-west China Table 1. Comparison of morphological characteristics of Elatostema bioppositum and E. oppositum. Characters E. bioppositum sp nov. E. oppositum Stem Simple, with brown furfuraceous Simple or branched, without furfuraceous Stipule Linear, lanceolate-linear or lanceolate, 12-25 mm long, 2.0-4.5 mm wide Subulate, 5-7 mm long, 1.0-1.5 mm wide Leaf blade Green after drying, major basal lateral veins absent and venation pinnate Brown-black after drying, the 2 major basal lateral veins asymmetric, one arising above the other basal vein Male inflorescence Opposite; 15-30 mm in diameter; peduncle 2-3 mm long Opposite; 6-16 mm in diameter; peduncle 5-35 mm long Female inflorescence Opposite; 7-15 mm in diameter Opposite or in pairs; 4-5 mm in diameter Achene c. 4-ribbed c. 10-ribbed Acknowledgements This work was supported by Hunan High School Scientific Program (11A109) and Key Discipline of Shaoyang University. We thank Yun-Xi Zhu for the drawing. References Bi, H.Y., Yang, Z.R. and Lin, Q. 2001. New taxa of Elatostema (Urticaceae) from Thailand and India. Bangladesh J. Plant. Taxon. 18(2): 149-152. Duan, L.D. and Lin, Q. 2003. Taxonomic notes on Elatostema xinningense W. T. Wang. Acta Phytotax. Sin. 41: 495-496. Duan, L.D. and Lin, Q. 2007. New records of Urticaceae from some provinces in China. Bull. Bot. Res., Harbin 27: 527-528. Duan, L.D. and Lin, Q. 2010. Elatostema cataractum (Urticaceae), a new species from Guizhou Province, China. Ann. Bot. Fenn. 47: 229-232. ELATOSTEMA BIOPPOSITUM, A NEW SPECIES FROM CHINA 183 Duan, L.D., Lin, Q. and Shao, Q. 2006a. Two new synonyms of Elatostema (Urticaceae). Acta Phytotax. Sin. 44: 474-476. Duan, L.D., Lin, Q. and Shao, Q. 2006b. The classification and distribution of Elatostema (Urticaceae) in Hunan, China. Life Sci. Res. 10: 144-150. Duan, L.D., Lin, Q., Yang, Z.R. and Shao, Q. 2011. New records of Urticaceae from twelve provinces in China. Acta Bot. Boreali-Occident. Sin. 31(5): 1050-1052. Lin, Q. and Duan, L.D. 2002a. Taxonomic notes on some species of Elatostema (Urticaceae) from China. Acta Phytotax. Sin. 40: 444-448. Lin, Q. and Duan, L.D. 2002b. New records for Elatostema and Pellionia (Urticaceae) in some provinces of China. J. Trop. Subtrop. Bot. 10: 356-360. Lin, Q. and Duan, L.D. 2003. Taxonomic notes on five species of Elatostema (Urticaceae) from China. Acta Bot. Yunnan. 25: 633-638. Lin, Q. and Duan, L.D. 2008. Two new species and a new series of Elatostema (Urticaceae) from China. Bot. J. Linn. Soc. 158: 674-680. Lin, Q., Friis, I. and Wilmot-Dear, C.M. 2003. Elatostema (Urticaceae). In: Wu, Z.Y. and Raven, P.H. (Eds), Flora of China, Vol. 5. Science Press, Beijing and Missouri Botanical Garden Press, St. Louis, USA. pp. 127-163. Lin, Q., Shui, Y.M. and Duan, L.D. 2011. Elatostema oppositum (Urticaceae), a new species from Yunnan, China. Novon 21: 212-215. Wang, W.T. 1995. Elatostema J.R. et G. Forst. In: Wang, W.T. and Chen, C.J. (Eds), Flora Reipublicae Popularis Sinicae, Vol. 23, No. 2. Science Press, Beijing, pp. 187-317. Wei, Y.G., Wen, F., Fu, L.F. and Wang, W.T. 2013. Three new species of Elatostoma J.R. Forst. & G. Forst. (Urticaceae) in limestone caves from Guangxi and Guixhou, China. Bangladesh J. Plant Taxon. 20(1): 1-8. Wu Z.Y., Li, D.Z., Wang, H. and Wang, W.T. 2012. One new series with its only new species of Elatostema (Urticaceae) from southeast Yunnan, China. Plant Divers. Resour. 24(2): 151-154. (Manuscript received on 18 March 2013; revised on 26 August 2013)