Erigeron neomexicanus |
Erigeron aureus |
|
---|---|---|
New Mexico fleabane |
alpine yellow fleabane, golden daisy, golden fleabane |
|
Habit | Perennials, 20–70 cm; taprooted, caudices woody. | Perennials, 1–15 cm; fibrous-rooted, caudices usually simple, rarely branched. |
Stems | erect, moderately to densely strigose (hairs appressed to ascending, 0.1–0.8(–2) mm, sometimes spreading at bases or throughout), eglandular or glands minute, non-capitate. |
erect to basally ascending, villoso-hirsute to ascending-strigose, minutely and inconspicuously glandular. |
Leaves | basal (sometimes persistent) and cauline; blades oblanceolate, margins usually deeply pinnatifid (lobes in 2–5 pairs), sometimes dentate to entire, faces strigose, eglandular; basal 10–60 × 6–35 mm, cauline gradually reduced distally. |
basal (persistent) and cauline; blades spatulate to oblanceolate-spatulate, 15–60 × 3–13 mm, cauline reduced distally, becoming bractlike, margins entire, faces finely hirsuto-villous to loosely strigose, eglandular. |
Involucres | 3.5–5 × 7–12 mm. |
(5–)6–8 × 8–15 mm. |
Ray florets | 70–150; corollas white, drying white, (2–)6–15 mm, laminae reflexing. |
30–50(–68); corollas yellow, 6–9(–10) mm, laminae tardily coiling. |
Disc corollas | 2.5–3.3 mm (throats somewhat white-indurate, not inflated). |
3–3.8 mm. |
Phyllaries | in 3–4 series, strigose to hirsute (hairs arising mostly from midregion), usually minutely glandular, rarely eglandular. |
in 2–3 series (purple), sparsely to densely woolly-villous (at least margins), sparsely minutely glandular. |
Heads | (1–)5–15(–30) in loosely corymbiform arrays. |
1. |
Cypselae | 1–1.3 mm, 2(–4)–nerved, faces sparsely strigose; pappi: (outer 0) inner (readily falling) of (8–)10–12 bristles. |
1.6–2 mm, 2-nerved, faces loosely strigose; pappi: outer of setae, inner of 14–25 bristles. |
2n | = 18, 36. |
= 18. |
Erigeron neomexicanus |
Erigeron aureus |
|
Phenology | Flowering (Jul–)Aug–Oct(–Dec). | Flowering Jun–Aug(–Sep). |
Habitat | Open, rocky sites, from grasslands into oak or pine woodlands, often with madrono, juniper, or fir | Ridges, crevices, talus and other rocky slopes, alpine tundra |
Elevation | (900–)1500–2700(–3000) m ((3000–)4900–8900(–9800) ft) | (1500–)1600–2700 m ((4900–)5200–8900 ft) |
Distribution |
AZ; NM; Mexico (Chihuahua, Sonora)
|
WA; AB; BC
|
Discussion | Relatively large, pinnatifid leaves are typical of Erigeron neomexicanus; plants with nearly entire leaves can be identified by the strongly perennial habit, white, reflexing rays, and 10–12 readily falling pappus bristles. Erigeron neomexicanus and E. oreophilus were treated by A. Cronquist (1947) as varieties of one species, and their morphologic similarity and the closeness of their geographic ranges support that hypothesis. But relatively few collections are found that could be regarded as intermediates, and both forms sometimes grow in proximity, apparently without a range of intermediates. In some Arizona mountain ranges, apparently only one or the other taxon occurs. Still, the possibility exists that these are populational segregants of a single species (see further comments in G. L. Nesom 1989d). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Erigeron aureus var. acutifolius has leaves apically acute (versus rounded to broadly obtuse, sometimes emarginate, in the typical form) and is known only from the type locality, a peat bog in British Columbia (Peace River District). It was not listed or otherwise recognized in a recent flora of that province (G. W. Douglas et al. 1998–2002, vol. 1). Erigeron ×arthurii B. Boivin was described as “sp. nov.” and was noted to have originated as a hybrid between E. acris and E. aureus. It was treated by E. H. Moss and J. G. Packer (1983) as a hybrid. Specimens cited by Boivin are from widely separated localities in southwestern British Columbia and adjacent Alberta. It was included at specific rank in the treatment by A. C. Budd et al. (1987) but not by H. J. Scoggan (1978–1979, part 4) or G. W. Douglas et al. (1998–2002, vol. 1). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 20, p. 277. | FNA vol. 20, p. 323. |
Parent taxa | Asteraceae > tribe Astereae > Erigeron | Asteraceae > tribe Astereae > Erigeron |
Sibling taxa | ||
Synonyms | E. delphiniifolius var. euneomexicanus, E. delphiniifolius subsp. neomexicanus | Haplopappus brandegeei, E. aureus var. acutifolius |
Name authority | A. Gray: Proc. Amer. Acad. Arts 19: 2. (1883) | Greene: Pittonia 2: 1691891 |
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