Symphyotrichum robynsianum |
Symphyotrichum tenuifolium |
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aster à longues feuilles, longleaf aster, Robyns' aster |
perennial saltmarsh American-aster, perennial saltmarsh aster |
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Habit | Perennials, 10–80 cm, colonial; long-rhizomatous. | Perennials, (20–)40–60(–100) cm, colonial or cespitose; rhizoma-tous. | ||||
Stems | 1, erect (± flexuous, often reddish), glabrous, hairy in lines distally. |
1–5+, ascending to erect (often with purple or purplish brown areas, flexuous, wiry), little-branched, usually glabrous, sometimes hairy in lines distally. |
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Leaves | stiff, margins sparsely serrulate or entire, ± revolute, scabrous, apices acute to acuminate, mucronulate, faces glabrous, sometimes midveins hairy; basal withering by flowering, long-petiolate, petioles narrowly winged, bases sheathing, blades lanceolate, ca. 20 × 3–5 mm, slightly attenuate to narrowly cuneate; proximal cauline withering by flowering, sessile or subpetiolate, blades linear-lanceolate to -oblanceolate, 100–200 × 4–8 mm, bases cuneate to attenuate, clasping; distal sessile, blades linear-lanceolate to linear, 10–110 × 1–7 mm, progressively reduced distally, bases cuneate to rounded, slightly clasping or not, margins entire. |
thick (fleshy), margins entire, faces glabrous; basal withering by flowering (new winter rosettes appearing at flowering), petiolate (petioles sheathing), blades ovate or oblanceolate, 15–20 × 5–15 mm, bases cuneate, apices rounded; proximal cauline withering by flowering, usually sessile, blades lanceolate, linear-lanceolate or -oblanceolate, to linear, 7–80(–150) × 1–6 (–12) mm, bases attenuate, margins entire, apices acuminate to acute; distal sessile, blades narrowly lanceolate to subulate, 10–110 × 0.5–5 mm, apices acuminate. |
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Peduncles | glabrous or ± densely pilose in lines, bracts 1–4, linear, sometimes inrolled distally, clasping, ciliate, distal 1–2 often subtending and surpassing involucres. |
0.6–4 (–6) cm, bracts 2–8, awl-shaped, grading into phyllaries. |
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Involucres | campanulate, 5–8.5 mm. |
narrowly turbinate, 4.1–9.5(–11) mm. |
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Ray florets | 20–35; corollas dark blue-violet, seldom white, laminae 8–13 × 1–1.5 mm. |
10–25; corollas white or pink, laminae (4.5–)5–8.5(–9.5) × 1.2–2 mm. |
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Disc florets | (18–)23–40; corollas yellow, 4–6.5 mm, tubes shorter than funnelform throats, lobes lanceolate, 0.8–1 mm. |
25–45(–54); corollas yellow becoming purplish, 3.4–6(–6.8) mm, tubes shorter than to equaling the narrowly funnelform throats (sparsely hairy at base), lobes ± erect, narrowly triangular, 0.5–0.8 mm. |
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Phyllaries | in 3–4 series, oblong-lanceolate, subequal, bases indurate 1/3–3/4, margins scarious, erose, hyaline, ciliate proximally, sparsely ciliolate distally, green zones lanceolate to linear, sometimes outer ± foliaceous, apices acuminate to long-acuminate, often foliaceous, mucronate to apiculate, faces glabrous, eglandular. |
in 4–5 series, lanceolate to subulate, bases indurate, rounded, margins hyaline, often tinged with purple, entire, green zones spatulate to oblanceolate-rhombic, apices acute, adaxial faces glabrous or minutely hairy distally. |
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Heads | in elongate, open, narrow, paniculiform or racemiform arrays, branches ascending, short, leafy, branch leaves smaller and reduced distally (heads 1–3 per branch). |
(1–)3–20(–40), in open, diffuse, paniculiform arrays, branches patent. |
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Cypselae | tan, obovoid, compressed, ca. 2.2–2.4 mm, 5–6-nerved, faces sparsely strigillose; pappi pinkish, 7–8 mm. |
light brown, narrowly obovoid to fusiform, sometimes ± compressed, 1.5–4(–4.5) mm, 5–6-nerved, faces sparsely strigillose; pappi tawny to white, 3–6.1 mm. |
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2n | = 64, 80. |
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Symphyotrichum robynsianum |
Symphyotrichum tenuifolium |
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Phenology | Flowering Aug–Sep. | |||||
Habitat | Wet or damp, open, sandy, gravelly, or rocky grounds, often calcareous, cracks in rocky stream or lake shores, limestone alvars, seasonally wet glades and swales, jackpine outwash plains | |||||
Elevation | 10–400 m (0–1300 ft) | |||||
Distribution |
MI; MN; WI; MB; ON; QC
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AL; CT; DE; FL; GA; LA; MA; MD; ME; MS; NC; NH; NJ; NY; RI; SC; TX; VA; West Indies
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Discussion | The name Aster longifolius Lamarck has been misapplied to this taxon. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Varieties 2 (2 in the flora). Along the Gulf of Mexico Coast in central and northern peninsular Florida, vars. tenuifolium and aphyllum intergrade in nearly all characters (S. D. Sundberg 2004). G. L. Nesom (2005d) treated the varieties as species. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 20, p. 530. | FNA vol. 20, p. 479. | ||||
Parent taxa | Asteraceae > tribe Astereae > Symphyotrichum > subg. Symphyotrichum > sect. Symphyotrichum | Asteraceae > tribe Astereae > Symphyotrichum > subg. Astropolium | ||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | Aster robynsianus | Aster tenuifolius | ||||
Name authority | (J. Rousseau) Brouillet & Labrecque: Phytologia 82: 138. (1997) | (Linnaeus) G. L. Nesom: Phytologia 77: 293. (1995) | ||||
Web links |