Elephantopus L., Sp. Pl.: 814. 1753.

Bunwong, Sukhonthip, Chantaranothai, Pranom & Keeley, Sterling C., 2014, Revisions and key to the Vernonieae (Compositae) of Thailand, PhytoKeys 37, pp. 25-101 : 66

Elephantopus L., Sp. Pl.: 814. 1753.

Type.

Elephantopus scaber L., Sp. Pl.: 814. 1753.

Description.

Annual or perennial herbs. Stems rosulate or caulescent, surface pubescent. Leaves simple, alternate or rosette, usually petiolate; lamina obovate, oblanceolate, elliptic, pilose-villose glandular; margin crenate, dentate or serrate; apex acute or obtuse, base attenuate, usually chartaceous. Capitulescences terminal or axillary, scapose or paniculate. Capitula discoid, tubular; clusters subtended by secondary foliose bracts, homogamous; florets bisexual and fertile. Phyllaries 8, in 2 series, decussate, persistent, oblong, outer surface puberulous or sometimes pilose-villose, glands capitate. Florets 4; corollas purple or white, glabrous or glandular, zygomorphic; corolla tubes slender; corolla lobes 5. Anthers 5, syngenesious, apical appendage acute, anther base not calcarate. Styles purple or white, 2-3-branched, inner surface covered with stigmatic papillae, outer surface covered with sweeping hairs reaching to below style bifurcation. Achenes usually clavate, 10-ribbed, pubescent, carpopodium present. Pappus in 1 series of usually 5 bristles dilated at base. Pollen lophate, 3-porate, without micropuncta.

Two species are recognized in Thailand.

Key to the species

1	Leaves cauline; capitulescences terminal and axillary	Elephantopus mollis
-	Leaves rosulate; capitulescences scapiform	Elephantopus scaber