255. Smallanthus Mackenzie ex Small, Man. S.E. Fl. 1406, 1509. 1933.
[For John Kunkel Small, 1869–1938, American botanist]
John L. Strother
Perennials [annuals, shrubs], 100–300[1200+] cm. Stems erect. Leaves cauline; opposite; petiolate (petioles usually winged) [sessile]; blades mostly deltate to ovate, usually ± palmately lobed, ultimate margins dentate to denticulate, faces hirtellous, pilosulous, or puberulent, gland-dotted (at least abaxially). Heads radiate, borne singly or (2–5) in crowded, corymbiform arrays. Involucres hemispheric, 8–15 mm diam. Phyllaries persistent, 12–13[–25+] in 2 series (outer 4–6 ovate to lanceolate [orbiculate], herbaceous, inner as many as rays, more membranous to scarious, narrower and shorter). Receptacles flat to convex, paleate (paleae obovate to spatulate, scarious). Ray florets 7–13[–25+], pistillate, fertile; corollas yellow [white or orange] (tubes hairy, laminae linear to elliptic [ovate]). Disc florets [20–]40–80[–150+], functionally staminate; corollas yellow [orange], tubes shorter than abruptly campanulate [funnelform] throats, lobes 5, deltate. Cypselae (obliquely inserted on receptacles, each shed separate from subtending phyllary) obovoid [quadrangular], somewhat compressed, finely 30–40-ribbed or -striate (not narrowed at bases, not apically beaked); pappi 0 (cypselae sometimes hairy at apices). x = 16.
Species ca. 20 (1 in the flora): United States, Mexico, South America.
SELECTED REFERENCES
Robinson, H. 1978. Studies in the Heliantheae (Asteraceae). XII. Re-establishment of the genus Smallanthus. Phytologia 39: 47–53. Turner, B. L. 1988. A new species of, and observations on, the genus Smallanthus (Asteraceae–Heliantheae). Phytologia 64: 405–409.
