Aster anticostensis Fernald:
Canada (North America)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

Canada

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

Global Range: This species is restricted to the Gaspe Peninusla, Anitcosti Island, Lake St. John (all in Quebec) and the St. John River basins (New Brunswick and Maine).

Perennials, 10–90 cm, colonial; long-rhizomatous. Stems 1, erect (straight, often reddish), glabrous. Leaves 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. Heads in elongate, loosely racemiform arrays, branches ascending, heads single at ends of primary branches or long pedicels. Peduncles 0.8–5.7 cm, slender, sparsely ot moderately pilosulous, bracts 3–5, linear-lanceolate, often crowded proximal to and surpassing heads. Involucres campanulate, 6–10 mm. Phyllaries 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. Ray florets 25–44; corollas usually pale purple or lilac, sometimes white, laminae 9.5–20 × 0.7–1.4 mm. Disc florets 29–52; corollas yellow becoming reddish purple, 5–6 mm, tubes slightly shorter than funnelform throats, lobes lanceolate, 0.6–0.7 mm. Cypselae reddish tan, obovoid, compressed, 1.5–2.8 mm, 4–5-nerved, faces strigillose; pappi yellowish, 7–8 mm. 2n = 80.

Aster anticostensis Fernald, Rhodora 17: 16. 1915; A. gaspensis Victorin; A. hesperius A. Gray var. gaspensis (Victorin) B. Boivin

Comments: Occurs on limestone outcrops or gravel along the banks of fast-flowing, high-volume rivers that cut through boreal forest. It usually grows on gentle slopes in unstable, gravelly, calcareous (alkaline) soil of sites subject to periodic flooding and scouring by ice and high spring waters. These cyclic disturbances maintained these sites at an early-successional stage (almost devoid of vegetation, full sunlight); the species depends on this process to keep shrubs and other competing species from taking over its habitat.

Note: For many non-migratory species, occurrences are roughly equivalent to populations.

Estimated Number of Occurrences: 21 - 80

Comments: 11 Quebec, 15 New Brunswick, 2 Maine (one is extirpated).

Canada

Rounded National Status Rank: N3 - Vulnerable

United States

Rounded National Status Rank: N1 - Critically Imperiled

Rounded Global Status Rank: G3 - Vulnerable

Reasons: Rare species of Gulf of St. Lawrence region, Quebec, and St. John River Valley of New Brunswick and Maine. Occurs on circumneutral, cobble or sand rivershores that are scoured by ice in the springtime (Maine Department of Conservation 1999). Approximately 15 occurrences are known (Maine Department of Conservation 1999; Labrecque 2001).

Environmental Specificity: Narrow. Specialist or community with key requirements common.

Comments: This species is restricted to calcareous river shores, in the geolittoral zone. This habitat is not frequent in Quebec. In New Brunswick, its natural habitat has been altered by the construction of dams.

Global Short Term Trend: Relatively stable (=10% change)

Comments: Probably relatively stable.

Comments: May be threatened by alterations to hydrology, off-road vehicles, residential development, and deer browsing (Labrecque 2001). Deer browsing is a serious problem at the Anitcosti Island site in Quebec (Labrecque 2001). Another threat at a population is erosion from logging practices in the river basin.

On the St. John River, this species is threatened by Reed Canary Grass, Phylaris. The bulk of the populations are not threatened by this non-native though.

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. novibelgii (J. Labrecque and L. Brouillet 1990). It hybridizes with S. novibelgii.

Comments: Accepted by Kartesz (1999) as a species, following recent studies.