Dieteria bigelovii

(A. Gray) D. R. Morgan & R. L. Hartman

Sida 20: 1394. 2003.

IllustratedEndemic
Basionym: Aster bigelovii A. Gray in War Department [U.S.], Pacif. Railr. Rep. 4(5): 97. 1857
Synonyms: Machaeranthera bigelovii (A. Gray) Greene
Treatment appears in FNA Volume 20. Treatment on page 397. Mentioned on page 396, 399.

Biennials or short-lived perennials. Stems, branches, and peduncles sometimes puberulent or canescent, stipitate-glandular. Leaf blades lanceolate to oblanceolate (linear to linear-oblanceolate in var. mucronata), mid 20–80 × (2–)5–15 mm, margins entire to irregularly dentate or serrate, faces glabrous or puberulent, often sparsely stipitate-glandular; distal bases usually cordate to auriculate, clasping. Involucres broadly turbinate to hemispheric. Phyllaries in 5–10 series, spreading to reflexed, apices long-acuminate, 2–6 mm, herbaceous (acute to acuminate, 1–3 mm in var. commixta), faces stipitate-glandular. Receptacles 4–9 mm diam. Ray florets pistillate, fertile; laminae blue to purple, 10–25 × 1–2 mm. Disc corollas 5–7(–8) mm. Cypselae sparsely appressed-hairy.

Distribution

V20-905-distribution-map.gif

Ariz., Colo., N.Mex., Utah, Wyo.

Discussion

Varieties 3 (3 in the flora).

Selected References

None.

Key

1 Involucres hemispheric, widths 2–3 times heights; phyllaries 90–100, 0.5–1 mm wide (at midpoint), apices long-acuminate, 2–5 mm Dieteria bigelovii var. mucronata
1 Involucres broadly turbinate to hemispheric, 1–2(–3) times heights; phyllaries 25–100, 1–2 mm wide (at midpoint), apices acute to long-acuminate > 2
2 Phyllaries 50–100, apices long-acuminate, 3–6 mm, ray florets 30–60 Dieteria bigelovii var. bigelovii
2 Phyllaries 25–50, apices acute to acuminate, 2–4 mm; ray florets 12–30 Dieteria bigelovii var. commixta