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Key to Asteraceae, Key N: Herbaceous composites with the leaves alternate or basal and the heads radiate, the rays white, pink, purple, and the pappus absent or essentially so

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1 Receptacles paleate (with chaff); [tribe Heliantheae].
..2 Stems not winged; leaves simple; disc florets and ray florets differing in color
..2 Stems usually winged; leaves simple or pinnately to palmately lobed; disc florets concolorous (of similar color) with ray florets
1 Receptacles epaleate (lacking chaff).
....3 Leaves 1-3 pinnately-lobed or pinnatifid.
......4 Plants arachnose or wooly pubescent throughout; [waif, SC; tribe Arctotideae]
......4 Plants glabrous or densely viscid but not wooly tomentose throughout (if hirsuto-pilose, this usually concentrated distally).
........5 Receptacles flat or broadly conic, not conspicuously pitted; heads in corymbiform arrays; pappus a short crown; rays white, pink, or purple adaxially; [widespread non-natives, tribe Anthemideae]
........5 Receptacles conic, pitted; heads borne singly (Aphanostephus) or in loose corymbiform arrays (Egletes); rays white adaxially; [natives primarily w. of MS river; tribe Astereae].
..........6 Plants aromatic, but not densely viscid, instead sometimes hairy distally; ray laminae not shorter than involucre; phyllary margins broadly scarious; pappus coroniform or a mix of variously shaped scales; [widespread w. of MS river]
..........6 Plants densely viscid with stipitate-glandular trichomes; ray laminae sometimes shorter than involucre; phyllary margins scarious or not; pappus of uneven rings; [TX]
....3 Leaves entire or toothed, but neither deeply lobed nor pinnatifid.
............ 7 Plants 1-3 cm tall, densely pin-cushioned (pulvinate); flowering heads sessile, borne singly, conspicuously nestled within the rosette leaves and proportionately of similar size; pappus persistent, of 12-35+ setiform scales in 1 series; phyllaries in 4-6+ series
............ 7 Plants of various size, but not densely pin-cushioned; flowering heads borne on stems, if peduncles short the heads not conspicuously nestled within similar-sized leaf rosettes; pappus various, phyllaries in 2-6 series.
............ ..8 Pappus of 5-40+ longer inner bristles plus shorter outer scales or setae (these sometimes falling); stems and leaves often (but not always) stipitate-glandular.
............ ....9 Inner barbellate bristles numerous (5-40+); stems and leaves usually glandular; plants tap-rooted, fibrous-rooted, or stoloniferous; annuals, biennials, or perennials
............ ....9 Inner bristles barbellate or thicker, fewer (ca. 5); stems and leaves glandular (C. asteroides) or eglandular (C. asteroides; C. belliloides); plants tap-rooted annuals
............ ..8 Pappus primarily of awns, scales, crowns, or thickened rings (these minute, 0.1-0.8 mm long), sometimes also accompanied by shorter inner scales or bristles; stems and leaves eglandular (sometimes minutely glandular in Chaetopappa bellidifolia).
............ ......10 Cypsela margins narrowly winged or winglike.
............ ........11 Receptacles obscurely pitted; pappus of 2-3 sclerified awns plus often with 7-12 shorter bristles or scales; [collectively widespread]
............ ........11 Receptacles smooth; pappus of 2 thin awns plus an elliptic ring of shorter awns; [s. TX]
............ ......10 Cypsela margins not narrowly winged (4-angled in Aphanostephus but lacking marginal wings).
............ ..........12 Receptacles conic, pitted; cypselae 4-angled; pappus of setiform to awn-tipped scales or short ciliate crowns (0.1-0.2 mm long, minute, thus requiring magnification)
............ ..........12 Receptacles flat or slightly convex, smooth (not pitted); cypselae variously shaped but not conspicuously 4-angled; pappus of minute, thickened rings (C. bellidifolia) or erose cuplike crowns (C. imberbis)
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