e-Flora of Thailand

Volume 13 > Part 2 > Year 2016 > Page 419 > Compositae (Asteraceae) > Tridax

Tridax procumbens L.wfo-0000086034

Sp. Pl. 2: 900. 1753; C.B.Clarke, Compos. Ind. 142. 1876; Hook.f., Fl. Brit. India 3: 311. 1881; Ridl., Fl. Malay Penins. 2: 186. 1923; Gagnep., Fl. Indo-Chine 3: 609. 1924; Kerr, Fl. Siam. 2(3): 282. 1936; Backer & Bakh.f., Fl. Java 1: 414. 1965; A.M. Powell, Brittonia 17: 80. 1965; Chang & Tseng, Fl. Reipubl. Popularis Sin. 75: 385. 1979; Grierson, Revis. Handb. Fl. Ceylon 1: 232. 1980; H.Koyama, Acta Phytotax. Geobot. 36: 67. 1985; Grierson & D.G.Long, Fl. Bhutan 2(3): 1611. 2001; Y.S.Chen & D.J.N.Hind, Fl. China 20–21: 864. 2011. Fig. 84.


Accepted Name : This is currently accepted.


Description : Perennial herb, 20–80 cm tall; stems procumbent, branched, obliquely erect at apex, hirsute. Leaves ovate or elliptic, 0.5–7 by 1–4 cm, apex acute or acuminate, base cuneate, margins serrate to coarsely incised-dentate or trilobed, both surfaces scabrid hirsute; petioles to 3 cm long. Inflorescences single, erect capitula; peduncles retrorsely hirsute and sparsely glandular, 10–20 cm long. Capitula ca 2 cm diam. at flowering; involucres campanulate, 5–7 by 5–6 mm; phyllaries ca 3-seriate, imbricate, outer ovate, 3.5–6 by 2–3.5 mm, herbaceous, apex acuminate, densely hirsute, inner membranous, oblong, 5–8 by 1.5–2 mm; receptacle shortly conical, paleae linear-lanceolate, 8–9 mm long. Ray florets 5–6 per capitulum; ray limbs creamy white, obovate-oblong, 4–5 mm long, apex deeply 2–3-lobed, basal tube 3–3.5 mm long, pubescent. Disc florets many per capitulum; corollas bright-yellow, 5.5–6.5 mm long, pubescent. Achenes narrowly obconical, 2–2.5 mm long, blackish, sparsely setuliferous, apex truncate and densely setuliferous; pappus of capillary bristles, ca 20, unequal in length, 4.5–6.5 mm long.


Thailand : NORTHERN: Chiang Mai (Doi Suthep), Lampang (Pang La to Huai Thak, Lampang), Nakhon Sawan; NORTH-EASTERN: Mukdahan (Dongman village, Phu Mu Forest Park); EASTERN: Nakhon Ratchasima Khao Yai NP, Pak Chong, Pak Thong Chai), Ubon Ratchathani; SOUTH-WESTERN: Kanchanaburi (Salakphra WS, Ban Sadao, Ban Khao Kaeng Khaep, Erawan NP, Sai Yok Noi), Prachuap Khiri Khan (Khao Sam Roi Yot, Ban Khunta Not); CENTRAL: Phra Nakhon Si Ayutthaya (Wang Noi), Saraburi (Phu Khae Botanic Garden, Ban Khrua, Tham Phra Phothisat, Hin Kong), Krung Thep Maha Nakhon (Bangkok), Samut Prakan (Bang Pu Kao); SOUTH-EASTERN: Chon Buri (Khao Khiao WS), Rayong; Chanthaburi (Khao Soi Dao); PENINSULAR: Phatthalung (Ban Pak Klong).


Distribution : Widely established in the tropical and subtropical regions of the world, though it is considered to be of C American origin (Mexico – type).


Ecology : Grassy slopes along roads, or dry ground in dipterocarp forests or bamboo thickets and sandy seashores, 0–600 m alt. Flowering all year round.


Vernacular : Tin tukkae (ตีนตุ๊กแก)(Central, Bangkok, Suphan Buri).


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