Launaea
in F. Cuvier, Dict. Sci. Nat. ed. 2, 25: 61, 321. 1822.
Taxon | Illustrator ⠉ | |
---|---|---|
Launaea intybacea Sonchus asper Sonchus oleraceus Arnoseris minima | Yevonn Wilson-Ramsey Yevonn Wilson-Ramsey Yevonn Wilson-Ramsey Barbara Alongi |
Annuals or biennials [perennials, shrubs, sometimes spiny], [5–] 30–150 cm; usually taprooted [stoloniferous]. Stems erect [prostrate], distally branched, glabrous [± hairy]. Leaves basal or basal and proximally cauline; petiolate or sessile; blades ± oblanceolate, often pinnately lobed, ultimate margins usually dentate (teeth usually ± prickly; faces glabrous [± hairy]). Heads in spiciform or racemiform to paniculiform arrays [borne singly]. Peduncles not inflated distally, bracteolate. Calyculi 0 (or bractlets intergrading with phyllaries). Involucres cylindric [urceolate, campanulate, or obconic], 3–5 [–16] mm diam. Phyllaries (persistent, reflexed in fruit) 18–25 in 3–5+ series, unequal, ovate to lanceolate (outer) or linear (inner), margins scarious, apices obtuse to acuminate (faces glabrous [± hairy]). Receptacles flat to convex, epaleate. Florets 25–30; corollas yellow to ochroleucous [cyanic]. Cypselae blackish to grayish, cylindric to fusiform or ± prismatic, sometimes ± compressed, beaks 0 (or lengths 0.05–0.1 times bodies), 4–5-ribbed (or grooved), ribs usually muricate, faces glabrous; pappi persistent or tardily falling [readily falling], double [simple], of 60–100+, outer, white, often ± coiled or crisped (frizzy) hairs or bristles in 2–3 series plus 80–120+, white, coarser, barbellulate to smooth bristles in 2–3+ series, all distinct or some basally connate. x = 9.
Distribution
Introduced; Mexico, West Indies, Central America, South America, also in Europe, n Africa, Atlantic Islands, sw, c Asia
Discussion
Species ca. 50 (1 in the flora).
Selected References
Lower Taxa
"fine" is not a number.