Erigeron bellidiastrum
Trans. Amer. Philos. Soc., n. s. 7: 307. 1840.
Annuals (or biennials?), 3.5–30 (–50) cm; taprooted. Stems erect to ascending, hirsutulous (hairs upcurved), usually eglandular, sometimes minutely glandular (var. arenarius). Leaves basal (sometimes persistent) and cauline or mostly cauline; blades linear to oblanceolate or spatulate, 10–60 (–80) × 2–6 (–9, or 15) mm, margins entire, lobed, or pinnately dissected, faces sparsely strigose, eglandular. Heads 1–12 usually in diffuse arrays (from branches beyond midstems or sometimes clustered distally). Involucres 3–5 × 5–7 (–11) mm. Phyllaries in 2–3 (–4) series, hispidulous, minutely glandular. Ray-florets 22–70 (some positioned among inner phyllaries); corollas white, often with abaxial lilac midstripe, drying white to bluish, 4–7.5 mm, laminae not coiling or reflexing. Disc corollas 2.2–3 mm (throats indurate and inflated). Cypselae 1–1.6 (–1.8) mm, 2-nerved, faces sparsely strigose; pappi: outer cartilaginous crowns, inner of 15–18 bristles.
Distribution
Ariz., Colo., Kans., Mont., N.Mex., Nebr., Okla., S.Dak., Tex., Utah, Wyo., n Mexico
Discussion
Varieties 3 (3 in the flora).
Erigeron bellidiastrum is recognized by its annual duration, upcurved hairs of the stem, relatively few rays, 1-seriate pappi, and by some ray florets consistently produced between the phyllaries, the mature cypselae of these held in place as the phyllaries reflex at maturity.
Selected References
None.
Lower Taxa
Key
| 1 | Basal and proximal cauline leaf margins deeply dentate to pinnately lobed | Erigeron bellidiastrum var. arenarius |
| 1 | Basal and proximal cauline leaf margins entire or rarely with pair of shallow teeth | > 2 |
| 2 | Proximal stems mostly 1–2(–2.5) mm wide; basal and proximal cauline leaf blades linear to linear-oblanceolate, 10–15(–30) × 1–2.5(–3) mm | Erigeron bellidiastrum var. bellidiastrum |
| 2 | Proximal stems mostly (2–)2.5–5 mm wide; basal and proximal cauline leaf blades oblanceolate, 20–40(–60) × 3–5(–15) mm | Erigeron bellidiastrum var. robustus |