Classification
 Subordinate Taxa
 Nomenclature
Scientific Name:
Cosmos Cav., Icon. (1791)
Vernacular Name(s):
Bidens; cosmos; Mexican aster
 Description

Annual or perennial herbs, rarely somewhat woody. Lvs opposite, simple and entire to lobed or pinnatisect, or 1–3-pinnate. Capitula pedunculate, solitary or in loose cymes. Involucral bracts in 2 rows; outer row usually foliaceous; inner row membranous. Receptacle flat; scales present. Outer florets sterile, ligulate, usually rose or violet to purple, rarely orange, yellow or white. Inner florets ☿, tubular. Achenes all similar, usually fusiform, sometimes linear, ± square in section, sometimes compressed, not winged, attenuated into beak at apex; pappus 0, or of 2–8 awns, usually with retrorse barbs, sometimes with antrorse barbs or hispid.

[From: Webb et al. (1988) Flora of New Zealand. Volume 4.]

 Biostatus
Exotic
Number of species in New Zealand within Cosmos Cav.
CategoryNumber
Exotic: Fully Naturalised1
Exotic: Casual1
Total2
 Bibliography
Cavanilles, A.J. 1791: Icones et Descriptiones Plantarum. Vol. 1. Edition 1.
Mabberley, D.J. 2008: Mabberley's plant book, a portable dictionary of plants, their classification and uses. Edition 3. Cambridge University Press.