Centipeda Lour.
Annual or perennial herbs, taprooted and sometimes rooting at nodes. Lvs simple, entire or toothed, alternate. Capitula axillary or terminal, sessile or shortly pedunculate; involucral bracts in 2 rows, with membranous margins. Receptacle hemispheric; scales 0. Outer florets ♀, in several rows, tubular, yellowish; inner florets ⚥, tubular. Achenes all similar, obpyramidal, square in section, distinctly 4-ribbed, with scattered glandular hairs on faces; ribs blunt, hairy; pappus 0.
Key
4 spp., Afghanistan, Asia, Australasia. Native sp. 1, naturalised 1.
The 2 Centipeda spp. which occur in N.Z. were not distinguished by Allan (1961) who treated all N.Z. material as C. orbicularis Lour. Although most specimens can be referred to one or other sp. with certainty, some material is difficult to identify, especially when dried and pressed, because no one character is diagnostic. The 2 spp. nevertheless differ in many characters and further field work will no doubt lead to improvement of the provisional treatment provided here. Frs of the 2 spp. are illustrated in Fig. 17.
