Sanvitalia

Annuals or perennials, (3–)10–30 cm. Stems prostrate to erect, branched from bases or ± throughout. Leaves cauline; opposite; petiolate or sessile; blades obovate or spatulate to linear, bases rounded to ± cuneate, margins entire [toothed or lobed], faces hairy. Heads radiate, borne singly. Involucres hemispheric to ± rotate, 4–12+ mm diam. Phyllaries persistent, 8–21 in 2–3 series (lanceolate to linear, outer distally herbaceous, others each with stiff, subulate appendage). Receptacles convex to conic, paleate (paleae conduplicate, scarious). Ray florets 5–20, pistillate, fertile; corollas white or yellow (laminae sessile, persistent, becoming papery). Disc florets 15–60, bisexual, fertile; corollas distally yellow to orange (sometimes drying white), tubes much shorter than funnelform throats, lobes 5, deltate. Cypselae ± terete or obscurely 3–4-angled to compressed or flattened (all usually tuberculate and usually bearing uncinate hairs; none, some, or all in each head winged); pappi persistent, of 3–4 awns. x = 8, 11.

Distribution

sw United States, Mexico, Central America, South America.

Discussion

Species 5 (3 in the flora).

Selected References

Strother, J. L. 1979. Extradition of Sanvitalia tenuis to Zinnia (Compositae–Heliantheae). Madroño 26: 173–179.

Torres, A. M. 1964. Revision of Sanvitalia (Compositae–Heliantheae). Brittonia 16: 417–433.

Lower Taxa

Sanvitalia abertii, Sanvitalia ocymoides, Sanvitalia procumbens

Key

1	Phyllaries 8–11; ray cypselae subterete, obscurely 3-angled, sulcate on each angle and on abaxial faces	Sanvitalia abertii
1	Phyllaries 12–21; ray cypselae 3-angled (clearly 3-faced, adaxial faces often 2–3-nerved)	> 2
2	Disc cypselae strongly dimorphic within heads: outer wingless, inner 1–2-winged	Sanvitalia procumbens
2	Disc cypselae ± monomorphic within heads, ± 4-angled to laterally compressed, none winged	Sanvitalia ocymoides