Horkelia fusca var. pseudocapitata

(Rydberg ex Howell) M. Peck

Man. Pl. Oregon, 398. 1941.

Common names: Intermountain horkelia
Endemic
Basionym: Horkelia pseudocapitata Rydberg ex Howell Fl. N.W. Amer., 180. 1898
Synonyms: H. fusca subsp. pseudocapitata (Rydberg ex Howell) D. D. Keck Potentilla douglasii var. pseudocapitata (Rydberg ex Howell) Jepson
Treatment appears in FNA Volume 9. Treatment on page 262. Mentioned on page 259, 260, 261, 263.

Stems 3–6 dm. Basal leaves green, 10–35(–40) cm; leaflets 4–6(or 7) per side, narrowly to broadly obovate, 10–30(–35) × (5–)10–20(–25) mm, 1/2 to nearly as wide as long, divided 1/5–1/4 to midrib into 8–14 teeth, surfaces not obscured, ± sparsely hirsute to glabrate. Cauline leaves 1–4(or 5); leaflets of proximalmost 2 or 3(–5) per side. Inflorescences green to reddish purple, congested to open, comprising 1/6–1/3 of stem, composed of 10–30-flowered glomerules, glandular hairs not or obscurely red-septate; bracts acute-lobed, not obscuring pedicels and flowers at maturity. Flowers: epicalyx bractlets 2–3.5(–4) mm; hypanthium 2 × 2.5–4 mm; petals (3–)4–6 mm; filaments 0.5–1.5 mm, usually longer than wide, anthers 0.5–0.6 mm; styles 1–1.5 mm. Achenes 1.6–1.8 mm. 2n = 28.


Phenology: Flowering summer.
Habitat: Dry meadow edges, often with sagebrush, aspen, and/or willows, open conifer woodlands, mainly on volcanic or granitic soil
Elevation: 900–2300 m

Distribution

V9 416-distribution-map.jpg

Calif., Idaho, Nev., Oreg.

Discussion

The application of the epithet pseudocapitata here differs significantly from that of P. A. Rydberg (1908c), D. D. Keck (1938), and most floras, who used it for the taxon that is here called var. brownii. Instead, var. pseudocapitata encompasses the bulk of what had been called var. (or subsp.) capitata, except in mountains bordering the Palouse Prairie in Idaho, Oregon, and Washington. For nomenclatural details, see B. Ertter and J. L Reveal (2007).

As here circumscribed, var. pseudocapitata is a relatively large, big-petaled variety that grows in the mountains in and bordering the northern Intermountain Region in northeastern California (primarily the Warner Mountains), northern Nevada, southeastern Oregon, and southern Idaho, extending northward along valleys from Camas to Blaine counties. Intermediate plants are common where the range intersects those of var. brownii, var. capitata, and var. parviflora, though in the core of its range var. pseudocapitata is reasonably distinctive and uniform.

Selected References

None.

Lower Taxa

None.
Barbara Ertter +  and James L. Reveal +
(Rydberg ex Howell) M. Peck +
Horkelia pseudocapitata +
Intermountain horkelia +
Calif. +, Idaho +, Nev. +  and Oreg. +
900–2300 m +
Dry meadow edges, often with sagebrush, aspen, and/or willows, open conifer woodlands, mainly on volcanic or granitic soil +
Flowering summer. +
Man. Pl. Oregon, +
H. fusca subsp. pseudocapitata +  and Potentilla douglasii var. pseudocapitata +
Horkelia fusca var. pseudocapitata +
Horkelia fusca +
variety +