Symphyotrichum laurentianum

(Fernald) G. L. Nesom

Phytologia 77: 286. 1995.

Common names: Gulf of St. Lawrence aster aster du golfe du Saint-Laurent
EndemicConservation concern
Basionym: Aster laurentianus Fernald Rhodora 16: 59, plate 109, figs. 1–5. 1914
Synonyms: Aster laurentianus var. contiguus Fernald Aster laurentianus var. magdalenensis Fernald
Treatment appears in FNA Volume 20. Treatment on page 500. Mentioned on page 467.

Annuals, 1–13+ cm. Stems 1, decumbent to erect (straight), glabrous. Leaves ± fleshy, margins entire, eciliate, apices obtuse, faces glabrous; basal deciduous at bolting, petiolate, blades oblanceolate 44–50 × 5–7 mm [cult.], bases attenuate; proximal cauline and some distal withering by flowering; cauline sessile, blades linear-lanceolate to spatulate, 15–55 × 1–4 mm, reduced distally, bases cuneate; distal sessile, blades linear-lanceolate to spatulate. Heads (disciform) in ± densely paniculiform arrays. Peduncles glabrous, bracts linear. Involucres campanulate, 5–8+mm. Phyllaries in 3–4 series, lanceolate, subequal, bases scarious, margins eciliate, green zones foliaceous (outer), apices obtuse, faces glabrous. Ray-florets 0. Pistillate florets 14–47+ in 2–3+ series; laminae 0 (corolla-tubes 2–2.4 mm, shorter than style-branches). Disc-florets 5–8+; corollas yellow, 3.1–3.9 mm, lobes deltate to triangular, 0.2–0.3 mm. Cypselae purple, obovoid, ± compressed, 2.8–2.9 mm, 2–4-nerved, faces strigillose; pappi white to yellowish white, 4.8–5.2 mm. 2n = 14.


Phenology: Flowering Aug–Sep.
Habitat: Brackish sand and mud, intertidal salt marshes, moist dune slacks
Elevation: 0 m

Discussion

Of conservation concern.

Symphyotrichum laurentianum is known only from the southern shores of the Gulf of St. Lawrence.

Selected References

None.

Lower Taxa

None.
not tailed +, rounded +  and obtuse +
distinct +
obtuse;obtuse +
subequal +
scarious +
usually triangular +  and linear +
usually deltate +  and lanceolate +
spiciform +, racemiform +, paniculiform +  and corymbiform +
indeterminate +  and determinate +
Luc Brouillet +, John C. Semple +, Geraldine A. Allen +, Kenton L. Chambers +  and Scott D. Sundberg† +
(Fernald) G. L. Nesom +
4.4 cm44 mm <br />0.044 m <br /> (5 cm50 mm <br />0.05 m <br />) +
spatulate;oblanceolate elliptic or ovate +
0.5 cm5 mm <br />0.005 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
cuneate +  and attenuate +
scarious +
Aster laurentianus +
1.5 cm15 mm <br />0.015 m <br /> (5.5 cm55 mm <br />0.055 m <br />) +
linear-lanceolate;spatulate +
reduced +
0.1 cm1 mm <br />0.001 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
rugulose +  and muricate +
barbellulate +  and barbellate +
Gulf of St. Lawrence aster +  and aster du golfe du Saint-Laurent +
not 2-lipped +  and actinomorphic +
at maturity , more or less ampliate , tubes usually shorter +
0.31 cm3.1 mm <br />0.0031 m <br /> (0.39 cm3.9 mm <br />0.0039 m <br />) +
beaked +, 2-ribbed +  and 5-ribbed +
strigillose +  and glabrous +
compressed +  and obovoid +
fertile +  and bisexual +
fertile +  and bisexual +
N.B. +, P.E.I. +  and Que. +
strigillose +  and glabrous +
winged +  and beaked +
dispersed +
Brackish sand and mud, intertidal salt marshes, moist dune slacks +
disciform +  and radiate +
indeterminate +
heterogamous +  and homogamous +
each +  and sessile +
0.4 cm4 mm <br />0.004 m <br /> (2.2 cm22 mm <br />0.022 m <br />) +
campanulate +
0.5 cm5 mm <br />0.005 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
1.8 cm18 mm <br />0.018 m <br /> (2.1 cm21 mm <br />0.021 m <br />) +
4.5mm;5mm +
2 (?) +  and 5 (?) +
0.1mm;0.2mm +
sessile +  and petiolate +
cauline +  and basal +
decurrent +
deltate +  and triangular +
not +  and hyaline +
coarsely serrate +  and crenate or entire +
2-carpellate +
white +  and yellowish white +
persistent +
25 +  and 40 +
0.48 cm4.8 mm <br />0.0048 m <br /> (0.52 cm5.2 mm <br />0.0052 m <br />) +
Flowering Aug–Sep. +
lanceolate +
styliferous +, neuter +  and pistillate +
bearing subulate enations +, hairy +  and bristly +
flat;slightly convex +
exalbuminous +
0.45 cm4.5 mm <br />0.0045 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
0.1mm;0.2mm +
Endemic +  and Conservation concern +
decumbent +  and erect +
appendaged +  and truncate +
papillate +  and smooth +
Aster laurentianus var. contiguus +  and Aster laurentianus var. magdalenensis +
Symphyotrichum laurentianum +
Symphyotrichum sect. Conyzopsis +
species +
funnelform-campanulate +  and cylindric +
at maturity , more or less ampliate , tubes usually shorter +
ampliate +
1 cm10 mm <br />0.01 m <br /> (13 cm130 mm <br />0.13 m <br />) +
tree +, shrub +  and subshrub +
usually diamond-shaped +  and lanceolate +