Symphyotrichum lentum |
Symphyotrichum subulatum |
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Suisun Marsh aster |
annual saltmarsh American-aster, annual saltmarsh aster, annual saltmarsh or eastern annual saltmarsh aster, aster subulé, eastern annual saltmarsh aster, Southwestern annual saltmarsh aster |
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Habit | Perennials, 40–150(–200) cm, colonial; long-rhizomatous. | Annuals, (10–)30–150 cm; tap-rooted. | ||||||||||||||||
Stems | 1–5, ascending to erect, glabrous. |
1, erect (often with purple or purplish brown areas), glabrous or glabrate, sometimes strigillose in leaf axils. |
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Leaves | thin, margins entire, apices acute, faces glabrous; basal withering by flowering, petiolate, blades linear to narrowly lanceolate, 100–150 × 5–10 mm, attenuate or cuneate, margins entire, apices acute, faces usually glabrous; proximalmost cauline usually withering by flowering, sessile, blades linear to narrowly lanceolate or oblanceolate, 50–90 × 5–8(–20) mm, bases attenuate or cuneate; distal sessile, blades 40–80 × 5–8(–15) mm, bases cuneate. |
thin (green to dark green), margins often strigilloso-ciliolate, faces glabrous; basal withering by flowering, long-petiolate (petiole bases sheathing), sparsely ciliate, blades ovate to oblanceolate, 10–90 × 6–14 mm, bases attenuate to cuneate, rounded, margins entire or serrulate or crenulate, apices rounded, obtuse, or acute; proximal cauline withering by flowering, petiolate, subpetiolate, or sessile, blades narrowly lanceolate or subulate, 20–100(–200) × 1.5–10(–20) mm, bases attenuate, margins subentire, entire, or serrulate, apices acute to acuminate; distal sessile, blades narrowly lanceolate to subulate, 5–113 × 0.5–5.5 mm, apices acuminate. |
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Peduncles | glabrous or sparsely villous, bracts 5–15, sessile, lance-linear to lanceolate, margins sometimes spiculate. |
(0.2–)0.5–4 cm, bracts 4–8(–17). |
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Involucres | campanulate, 5–8 mm. |
cylindric to turbinate, 5–7(–8.2) mm. |
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Ray florets | 20–45+; corollas violet, laminae 10–18 × 1–2 mm. |
16–30(–54) in 1–3 series; corollas white, pink, or lavender, laminae 1.3–7 × 0.2–1.3 mm. |
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Disc florets | 35–70+; corollas yellow, 5–7 mm, lobes triangular, 0.8–1.5 mm. |
4–10(–13); corollas yello, sometimes tinged with purple, 3.4–5.2 mm, throats narrowly funnelform, lobes ± spreading to erect, narrowly triangular, 0.3–0.7 mm, glabrous. |
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Phyllaries | in 4–5 series, narrowly oblong (outer) to linear (inner), unequal (outer at least 3 times longer than wide), bases (outer) indurate 1/2 or less, margins scarious proximally, eciliate or ciliolate, green zones lanceolate to elliptic, apices acute to acuminate, faces glabrous. |
in 3–5 series, broadly or narrowly lanceolate to subulate, unequal, bases indurate, margins hyaline, often purple-tinged, entire, green zones lanceolate (usually narrow, sometimes broad and covering most of distal portion), apices acute, faces glabrous. |
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Heads | in paniculiform arrays, branches some at least 25 cm. |
(10–) 30–100(–150), in open, diffuse, paniculiform arrays. |
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Cypselae | brown, cylindric to obovoid, not compressed, 3–4 mm, 2–4-nerved, faces glabrous or hairy; pappi white, 5–7 mm. |
light brown to purple, narrowly obovoid to fusiform, sometimes ± compressed, (1.2–)1.5–2.7(–3) mm, 5-nerved, faces sparsely strigillose; pappi white, (3–)3.5–5.5 mm. |
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2n | = 16, 64. |
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Symphyotrichum lentum |
Symphyotrichum subulatum |
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Phenology | Flowering Jul–Aug. | |||||||||||||||||
Habitat | Salt marshes, wet grasslands | |||||||||||||||||
Elevation | 0–200 m (0–700 ft) | |||||||||||||||||
Distribution |
CA
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AL; AR; AZ; CA; CT; DE; FL; GA; IL; IN; KS; LA; MA; MD; ME; MI; MS; NC; NE; NH; NJ; NM; NV; NY; OH; OK; PA; RI; SC; TN; TX; UT; VA; NB; ON; Mexico; Central America; South America; West Indies; Bermuda [Widely introduced worldwide]
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Discussion | Symphyotrichum lentum is known only from the Sacramento Valley, North Bay County, lower Sacramento River, and San Francisco Bay areas. Probable intergrades with S. chilense have been noted. of conservation concern (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Varieties 5 (5 in the flora). Five varieties of Symphyotrichum subulatum are recognized for North America based on differences in chromosome number, ray lamina color and size, array shapes, number of series of ray florets, number of disc and ray florets, and other, more cryptic characters (S. D. Sundberg 2004). These varieties were treated as species by G. L. Nesom (1994b, 2005d). Variety ligulatum is apparently an obligate outcrosser and is the least variable variety (Sundberg). Other varieties are self-compatible, which could facilitate the fixation of mutations in populations. The five varieties are nearly entirely allopatric, and intermediates between pairs of varieties are not uncommon where they approach one another. Populations that are intermediate in ray lamina size between vars. ligulatum and parviflorum are widespread in southern Texas, New Mexico, Arizona, and northern Mexico. Intermediates between vars. elongatum and parviflorum and between vars. elongatum and subulatum occur in Florida. Despite these observations, hybridization experiments and chromosome number differences suggest that the varieties are mostly reproductively isolated (S. D. Sundberg 1986, 2004). In older floras the name Aster exilis Elliott has been applied to Symphyotrichum subulatum vars. ligulatum and parviflorum. The status of this name is uncertain; the type specimen has been lost and the description of the plant is inadequate for determining the taxon to which the name should be applied (G. L. Nesom 1994b; S. D. Sundberg 2004). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 20, p. 536. | FNA vol. 20, p. 480. | ||||||||||||||||
Parent taxa | Asteraceae > tribe Astereae > Symphyotrichum > subg. Symphyotrichum > sect. Occidentales | Asteraceae > tribe Astereae > Symphyotrichum > subg. Astropolium | ||||||||||||||||
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Synonyms | Aster lentus, Aster chilensis var. lentus, Aster chilensis var. sonomensis | Aster subulatus | ||||||||||||||||
Name authority | (Greene) G. L. Nesom: Phytologia 77: 286. (1995) | (Michaux) G. L. Nesom: Phytologia 77: 293. (1995) | ||||||||||||||||
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