Erigeron grandiflorus |
Erigeron aphanactis |
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large-flower daisy, large-flower fleabane, onestem fleabane, Rocky Mountain alpine fleabane |
rayless shaggy fleabane |
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Habit | Perennials, 2–25 cm; rhizomatous, fibrous-rooted, caudices or rhizomes crownlike or branches relatively short and thick. | Perennials, 2–20(–30) cm; taprooted, caudices branched. | ||||
Stems | erect to decumbent-ascending, sparsely to moderately pilose to villoso-hirsute, often stipitate-glandular over all or part. |
erect to slightly decumbent-ascending, canescent-hirsute, densely stipitate-glandular. |
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Leaves | basal (persistent) and cauline (petioles equaling or shorter than blades); blades oblanceolate to obovate or spatulate, 10–60(–90) × 3–8(–14) mm, cauline abruptly or gradually reduced distally, margins entire (apices rounded), faces sparsely hirsutulous or villous to sparsely strigose or glabrate, sometimes sparsely glandular. |
basal (persistent) and cauline (petioles prominently ciliate, at least on proximal portions, hairs thick-based, spreading); basal blades linear-oblanceolate to spatulate, 20–80 × 2–7 mm; cauline gradually or abruptly reduced distally, sometimes bractlike (stems scapiform), margins entire, faces canescent-hirsute, densely stipitate-glandular (hairs finer). |
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Involucres | 5–8(–10) × 8–20 mm. |
4–6 × 7–15 mm. |
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Ray florets | 50–130; corollas blue to pink or purplish, rarely white, 7–11(–15) mm (mostly 1–2 mm wide), laminae coiling. |
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Ray (pistillate) florets | 30–45; corollas usually tubular, lacking laminae, or laminae shorter than involucres. |
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Disc corollas | 2.4–4(–5) mm. |
2.8–4.5 mm (throats white-indurate and inflated, conspicuously puberulent). |
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Phyllaries | in 2–3 series (green or purplish), moderately to densely woolly-villous (hairs flattened, cross walls sometimes reddish), minutely glandular at least apically. |
in 2–3 series, coarsely hirsute, densely minutely glandular. |
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Heads | 1. |
(disciform) 1–4. |
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Cypselae | 1.8–2.4 mm, 2-nerved, faces strigose; pappi: outer of setae, inner of (7–)10–18(–22) bristles. |
1.5–1.8 mm, 2-nerved, faces sparsely strigose (carpopodia whitish); pappi: outer of scales or setae, inner of 7–20 bristles. |
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2n | = 18, 27. |
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Erigeron grandiflorus |
Erigeron aphanactis |
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Phenology | Flowering Jul–Aug(–Sep). | |||||
Habitat | Rocky sites, meadows, alpine or near timberline | |||||
Elevation | 2900–4200 m (9500–13800 ft) | |||||
Distribution |
AZ; CO; ID; MT; NM; OR; UT; WY; AB; BC
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AZ; CA; CO; NM; NV; OR; UT
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Discussion | S. A. Spongberg (1971) recognized only the triploid populations as Erigeron grandiflorus and assigned the diploid ones to E. simplex. He hypothesized that the triploids incorporate genomic elements from an ancestor other than E. simplex. Based on his comments and annotations, however, triploids in southern Canada and the western United States apparently differ from the much more widespread diploids only quantitatively, having involucres and florets at the higher end of size ranges. Morphologic distinctions between the ploidal races do not provide a basis for consistent distinction. Spongberg (p. 200) also noted that “because of the intergrading of morphologic features of plants of Erigeron grandiflorus...the single most important criterion indicative of this taxon is highly irregular [in shape] and greatly abortive pollen.” These pollen features result from meiotic anomalies associated with the triploid condition. Specimen citations by A. Cronquist (1947) for Erigeron grandiflorus were mostly from collections of the species treated here as E. porsildii. He also cited two collections from southwestern Alberta; those and the type collection of E. grandiflorus (from the same region) are disjunct by more than 1500 kilometers from the more northern range of E. porsildii and instead lie at the northern extremity of the range of what previously has generally been identified as E. simplex. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Varieties 2 (2 in the flora). Erigeron aphanactis is distinguished from E. austiniae by its conspicuously puberulent (versus essentially glabrous) disc corollas and white (versus yellow) carpopodia; it also is similiar in habit and vestiture to E. concinnus, which has conspicuous white to pinkish rays. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 20, p. 324. | FNA vol. 20, p. 291. | ||||
Parent taxa | ||||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | E. simplex | E. concinnus var. aphanactis | ||||
Name authority | Hooker: Fl. Bor.-Amer. 2: 18, plate 123. (1834) | (A. Gray) Greene: Fl. Francisc., 389. (1897) | ||||
Web links |