Camchaya Gagnep., Notul. Syst. 4: 14. 1920.

Bunwong, Sukhonthip, Chantaranothai, Pranom & Keeley, Sterling C., 2014, Revisions and key to the Vernonieae (Compositae) of Thailand, PhytoKeys 37, pp. 25-101 : 50

Camchaya Gagnep., Notul. Syst. 4: 14. 1920.

Type.

Camchaya kampotensis Gagnep., Notul. Syst. 4: 14. 1920.

Description.

Annual herbs. Stems erect, pubescent. Leaves simple, alternate, usually petiolate; lamina ovate to lanceolate, pubescent with hairs and glands, margin serrate, apex acute to acuminate, base attenuate, usually chartaceous. Capitulescences terminal or axillary, paniculate or corymbose. Capitula campanulate or hemispherical, pedunculate, homogamous; florets bisexual and fertile. Involucres campanulate or hemispherical. Phyllaries imbricate, persistent, the outer and the middle ones ovate or lanceolate, the inner ones linear-oblong, sometimes pubescent, glands capitate. Corollas purple or white, narrowly funnelform, pubescent with hairs and/or capitate glands; corolla lobes 5. Anthers apical appendage acute, base rounded. Styles purple, 2-branched, slender, acute, inner surface covered with stigmatic papillae, outer surface and shaft covered with sweeping hairs reaching to below style bifurcation. Achenes obovate, usually 10-ribbed, carpopodium absent. Pappus in one series of often deciduous bristles. Pollen echinolophate, 6-porate, without micropuncta.

Seven species are recognized in Thailand.

Key to the species

1	Phyllaries broadly ovate without marginal spines	2
-	Phyllaries broadly ovate with marginal spines	3
2	Achenes 4-5-ribbed	Camchaya gracilis
-	Achenes 10-ribbed	Camchaya thailandica
3	Achenes 5 (6-9)-ribbed	Camchaya pentagona
-	Achenes 10-ribbed	4
4	Phyllaries without glands, spines up to 10 mm	Camchaya spinulifera
-	Phyllaries with glands, spines up to 5 mm	5
5	Phyllaries acuminate; achenes 2.5-3 mm long	Camchaya kampotensis
-	Phyllaries aristate or apiculate; achenes 1.5-2 mm	6
6	Leaves with T-shaped hairs; phyllaries spinose ≤ 1 mm long	Camchaya loloana
-	Leaves without T-shaped hairs; phyllaries spinose ≥ 1 mm long	Camchaya tenuiflora