Plants 30-90 cm, glabrous or sparsely pubescent. Leaves: petioles ca. 0.5 cm; blades 2.5-6.5 cm, ultimate lobes to 1 mm wide, margins usually spinulose-ciliate, apices acute to obtuse. Peduncles 10-30 cm. Calyculi of spreading to reflexed, linear-oblong to narrowly lanceolate bractlets 6-9 mm, apices acute. Involucres (3-)5-10(-15) mm diam. Phyllaries erect, oblong, 5-8 mm, apices acute. Ray corollas white to rose-pink or violet, laminae cuneate-obovate, 5-9 mm, apices dentate. Disc corollas 4-5 mm. Cypselae 9-16 mm, setulose; pappi of 2-4 erect awns 2-3 mm. 2n = 24.
Flowering summer-fall. Open or forested slopes and canyons, sometimes in disturbed and cultivated areas; 100-3000 m; Ariz., Colo., Md., Mass., Mo., N.Mex., R.I., Tex.; Mexico.
Within the flora area, Cosmos parviflorus is native only in the southwestern United States.
FNA 2006, Kearney and Peebles 1969, McDougall 1973
Duration: Annual Nativity: Native Lifeform: Forb/Herb General: Herbaceous annuals with slender, leafy stems, herbage glabrous to sparsely pubescent. Leaves: Leaves opposite, dissected into narrow lobes, apices acute to obtuse, margins spinulose-ciliate. Flowers: Heads radiate, rays white or rosy with dentate apices, disk flowers yellow, perfect and fertile, involucres hemispheric, receptacles flat or nearly so and chaffy, phyllaries thin, in 2 distinct, unlike series, the outer part of the calyx narrow, elongate and herbaceous, subtending the inner, the inner wider and shorter with definite scarious margins; inflorescences borne solitary on stems and branches. Fruits: Achenes fusiform, conspicuously beaked. Pappus of 2-4 retrorsely hispid awns. Ecology: Found in open pine forest, hillsides, canyons, and cultivated lands, from 4,000-9,000 ft (1219-2743 m); flowering July-October. Distribution: Arizona, Colorado, Maryland, Massuchutes, Missouri, Mexico, New Mexico, Rhode Island, and Texas; Mexico. Notes: This lovely species is often used as an ornamental. FNA notes Cosmos parviflorus as native only in the southwestern United States. The lower, herbaceous bract often appears separate from the upper, with a small space in between. Ethnobotany: A cold infusion of the dried leaves was used as ceremonial chant lotion. Etymology: Cosmos is from the Greek kosmos, for ornament or decoration, while parviflorus means small flowered. Synonyms: Coreopsis parviflorus Editor: LCrumbacher 2011