TREATMENT FROM THE JEPSON MANUAL (1993) |
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©Copyright 1993 by the Regents of the University of California
For up-to-date information about California vascular plants, visit the Jepson eFlora. |
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Annual to perennial herb, rarely shrub, sometimes armed with prickles
Stem generally branched
Leaves simple, generally in basal rosettes and cauline, generally opposite, ± fused at base around stem, entire, toothed, or pinnately lobed or dissected, petioled or sessile; stipules 0
Inflorescence: head, terminal, on long peduncle, many-flowered, dense, ± spheric or cylindric, subtended by involucre; each flower generally enclosed ± at base by an involucel of 12 generally fused bractlets, this generally expanded above or in fruit, generally subtended by a receptacle bract
Flower bisexual, ± bilateral, especially outermost; calyx limb cup-shaped or divided into 45(10) linear or bristle-like segments; corolla ± funnel-shaped, lobes 45, < tube, generally unequal; stamens generally 4, attached to corolla tube, alternate lobes; ovary inferior, 1-chambered, style slightly exserted from corolla, stigma 2-lobed
Fruit: achene, enclosed by sometimes enlarged involucel, generally topped by persistent calyx
Genera in family: 1011 genera, 270350 species: Eur to e Asia, c&s Africa; several cultivated for ornamental
Reference: [Moore 1976 Flora Europaea 4:5672]
Biennial, armed with prickles, sometimes ± throughout
Stem erect, generally < 2 m, stout, few-branched, rough-hairy
Leaf generally < 5 dm, entire or toothed
Inflorescence generally ± cylindric; involucre bracts unequal, > flowers, linear, stiff; receptacle bract ending in a spine
Flower: calyx limb cup-shaped, 4-lobed, persistent; corolla generally lavender, rarely white, tube long, lobes 4, unequal; stamens 4
Fruit 4-angled, hairy
Species in genus: ± 15 species: Eur, w Asia, Africa
Etymology: (Greek: thirst, from leaf bases that in some species hold water)
Reference: [Ferguson & Brizicky 1965 J Arnold Arb 46:362365]