Symphyotrichum tenuifolium |
Symphyotrichum anticostense |
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perennial saltmarsh American-aster, perennial saltmarsh aster |
Anticosti American-aster, Anticosti aster, Anticosti Island aster, aster d'Anticosti |
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Habit | Perennials, (20–)40–60(–100) cm, colonial or cespitose; rhizoma-tous. | Perennials, 10–90 cm, colonial; long-rhizomatous. | ||||
Stems | 1–5+, ascending to erect (often with purple or purplish brown areas, flexuous, wiry), little-branched, usually glabrous, sometimes hairy in lines distally. |
1, erect (straight, often reddish), glabrous. |
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Leaves | 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. |
coriaceous, margins remotely serrulate or entire, slightly revolute, scabrous, apices mucronulate, faces glabrous; basal withering by flowering, long-petiolate (petioles narrowly winged, bases sheathing), blades lanceolate to oblanceolate, ca. 55+ × 3+ mm, bases slightly attenuate, apices acute; proximal cauline mostly withering by flowering, petiolate (petioles narrowly winged, sheathing), blades lanceolate or oblanceolate to linear-lanceolate or -oblanceolate, arcuate, 90–160 × 5–18 mm, bases cuneate to slightly attenuate, margins entire or serrulate, apices acute; distal sessile, blades linear to linear-lanceolate, 8–50 × 1.5–5 mm, progressively reduced distally, more strongly so in arrays, bases cuneate to rounded, sometimes slightly clasping, apices acute to acuminate. |
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Peduncles | 0.6–4 (–6) cm, bracts 2–8, awl-shaped, grading into phyllaries. |
0.8–5.7 cm, slender, sparsely ot moderately pilosulous, bracts 3–5, linear-lanceolate, often crowded proximal to and surpassing heads. |
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Involucres | narrowly turbinate, 4.1–9.5(–11) mm. |
campanulate, 6–10 mm. |
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Ray florets | 10–25; corollas white or pink, laminae (4.5–)5–8.5(–9.5) × 1.2–2 mm. |
25–44; corollas usually pale purple or lilac, sometimes white, laminae 9.5–20 × 0.7–1.4 mm. |
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Disc florets | 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. |
29–52; corollas yellow becoming reddish purple, 5–6 mm, tubes slightly shorter than funnelform throats, lobes lanceolate, 0.6–0.7 mm. |
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Phyllaries | 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. |
in 2–3 series, oblong-oblanceolate or -spatulate (outer) or oblong-lanceolate to linear-lanceolate or linear (inner), ± unequal, bases indurate 1/3–3/4, margins hyaline, scarious, erose distally, sparsely ciliolate distally, green zones lanceolate, outer often foliaceous distally, apices acute to long-acuminate, ± spreading, faces glabrous. |
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Heads | (1–)3–20(–40), in open, diffuse, paniculiform arrays, branches patent. |
in elongate, loosely racemiform arrays, branches ascending, heads single at ends of primary branches or long pedicels. |
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Cypselae | 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. |
reddish tan, obovoid, compressed, 1.5–2.8 mm, 4–5-nerved, faces strigillose; pappi yellowish, 7–8 mm. |
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2n | = 80. |
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Symphyotrichum tenuifolium |
Symphyotrichum anticostense |
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Phenology | Flowering Aug–Sep. | |||||
Habitat | Calcareous, gravelly shores of rivers, lakeshore limestone pavements | |||||
Elevation | 0–100 m (0–300 ft) | |||||
Distribution |
AL; CT; DE; FL; GA; LA; MA; MD; ME; MS; NC; NH; NJ; NY; RI; SC; TX; VA; West Indies
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ME; NB; QC
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Discussion | 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.) |
Of conservation concern. Symphyotrichum anticostense is known from disjunct areas: western Lake St. John, southern Anticosti Island, southern streams of the Gaspé Peninsula (Quebec), Restigouche River (Quebec–New Brunswick), and St. John (New Brunswick) and Aroostook (Maine; A. Haines 2000) rivers. It is an allopolyploid derivative of the cross between the calcareous fen species S. boreale and the widespread shore species S. novi-belgii (J. Labrecque and L. Brouillet 1990). It hybridizes with S. novi-belgii. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 20, p. 479. | FNA vol. 20, p. 529. | ||||
Parent taxa | Asteraceae > tribe Astereae > Symphyotrichum > subg. Astropolium | Asteraceae > tribe Astereae > Symphyotrichum > subg. Symphyotrichum > sect. Symphyotrichum | ||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | Aster tenuifolius | Aster anticostensis, Aster gaspensis, Aster hesperius var. gaspensis | ||||
Name authority | (Linnaeus) G. L. Nesom: Phytologia 77: 293. (1995) | (Fernald) G. L. Nesom: Phytologia 77: 275. (1995) | ||||
Web links |