海南菊属 hai nan ju shu

Authors: Yilin Chen, Ying Liu, Qiner Yang & Bertil Nordenstam

Herbs, perennial. Rhizomes thickened. Leaves rosulate, long petiolate; blade ovate to obovate, pinnately veined. Capitula solitary, terminal. Involucres hemispheric, ecalyculate; phyllaries ca. 13, lanceolate, apex acuminate. Ray florets ca. 13; lamina white, elliptic-oblong, apex acuminate, often 2-denticulate. Disk florets many; corolla white. Anthers rounded at base; apical appendage ovoid with abaxial cells obviously enlarged; endothecial cell wall thickenings polar and radial. Antheropodia cylindric. Pollen grains triporate, helianthoid. Style branches truncate. Achenes obovoid. Pappus absent. x = 29*.

● One species: China.

The genus has polar and radial endothecial cell wall thickenings, cylindric antheropodia, and a basic chromosome number of x = 29, all of which are characteristic of subtribe Tussilagininae. Nevertheless, recent molecular data suggest a position within subtribe Senecioninae and a relationship to the Macaronesian genus Pericallis, which shares some unusual characters with Hainanecio such as the non-yellow florets and the helianthoid pollen.

Lower Taxon

• Hainanecio hainanensis (C. C. Chang & Y. C. Tseng) Y. Liu & Q. E. Yang