Schkuhria

Annuals, 5–50+ cm. Stems erect, simple or branched (usually distally). Leaves mostly cauline; mostly opposite (distal sometimes alternate); petiolate or sessile; blades linear to filiform or 1–2-pinnately lobed (lobes 3–7+, linear to filiform), ultimate margins entire, faces sparsely hairy (hairs bulbous, conic, or fusiform, 0.1–0.3 mm), glabrescent, usually gland-dotted. Heads radiate or discoid, usually in loose, corymbiform to paniculiform arrays. Involucres obconic-obpyramidal to ± turbinate or hemispheric, 3–6 mm diam. (subtended by 0–3 bractlets). Phyllaries persistent, 4–6+ in 1–2 series (spreading or reflexed in fruit, distinct, obovate to oblanceolate, subequal, thin-herbaceous to membranous, margins membranous, often purplish or yellowish). Receptacles convex, pitted, epaleate. Ray florets 0 or 1–2, pistillate, fertile; corollas yellow or white. Disc florets 2–8(–30+), bisexual, fertile; corollas yellow to yellowish, sometimes red-tipped (± stipitate-glandular), tubes shorter than or about equaling campanulate to funnelform throats, lobes 5, deltate. Cypselae narrowly obpyramidal, 4-angled, finely nerved, ± hirsutulous to villous (at least at bases and/or on angles); pappi persistent, of 8+ spatulate to lanceolate (basally and/or medially thickened, distally and/or laterally scarious) scales (all, some, none, or the alternate ones ± aristate). x = 11.

Distribution

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

Discussion

Species 2 or perhaps more (2 in the flora).

According to B. G. Baldwin et al. (2002), among others, Schkuhria is closely related to Achyropappus Kunth and to Bahia.

Selected References

Heiser, C. B. 1945. A revision of the genus Schkuhria. Ann. Missouri Bot. Gard. 32: 265–278.

Lower Taxa

Schkuhria multiflora, Schkuhria pinnata

Key

1	Phyllaries ± hirsutulous and gland-dotted; ray florets 0; disc florets 15–30	Schkuhria multiflora
1	Phyllaries gland-dotted, otherwise usually glabrous; ray florets usually 1–2, sometimes 0; disc florets 2–6(–8+)	Schkuhria pinnata