Gen. Hist. 4: 616. 1837/1838.
Herbs, perennial, 0.9–3.8 (–4) dm; from a woody caudex; with a taproot. Stems few-to-many, ascending to erect, branched, especially near base, sometimes unbranched, hairs sparse to dense, spreading to retrorse, long, sometimes short, soft to stiff, usually mixed with short-glandular ones, sometimes viscid. Leaves brown or purplish, sometimes green, linear to lanceolate or broadly lanceolate, 1.2–7 (–7.5) cm, not fleshy, margins plane, sometimes ± wavy, involute or flat, (0–) 3–5-lobed, rarely with secondary lobes, apex acuminate to rounded; lobes spreading, oblong or lanceolate to linear-lanceolate, apex acute to rounded. Inflorescences 2.5–20 × 1.5–5 cm; bracts proximally greenish or dull purplish, distally pink, magenta, pink-purple, reddish-pink, pale-yellow, pale yellow-orange, pale orange, or white, rarely reddish or orange-red, lanceolate to oblong, 3–5 (–9) -lobed, sometimes with secondary lobes; lobes spreading or ascending, oblanceolate or linear, proximal lobes often much longer than distal, proximal lobes arising below or a little above mid length, apex acute to rounded. Calyces proximally green, yellow, brown, or purple, lobes colored as bract lobes, sometimes with a yellow band between proximal and distal parts, 13–25 (–28) mm; abaxial clefts 3–8 mm, adaxial 5–9 (–12) mm, clefts 30–50% of calyx length, deeper than laterals, lateral (1–) 1.5–4 (–5) mm, 10–25% of calyx length; lobes lanceolate to oblong, abaxials wider than adaxials, apex acute to rounded. Corollas straight, 18–27 (–32) mm; tube 8–17 mm; beak usually long-exserted, adaxially green or pink, 8–15 mm; abaxial lip deep green, reduced, inconspicuous, 1–2.5 mm, 5–20% as long as beak; teeth incurved to ascending, deep green, 0.5–1.5 mm.
Idaho, Mont., Nev., Oreg., S.Dak., Utah, Wyo.
Varieties 3 (3 in the flora).
Much confusion exists concerning Castilleja angustifolia and the closely related C. chromosa. Sometimes C. chromosa is treated as a variety of C. angustifolia, using the name C. angustifolia var. dubia. The latter name is used here to represent a different assemblage of plants, not including C. chromosa. At other times, C. chromosa is synonymized completely under C. angustifolia. However, the two species are in most cases easily separable, and where they are sympatric there is little evidence of intergradation. Both C. angustifolia var. dubia and C. chromosa are accepted here. See additional comments under 3b. C. angustifolia var. dubia and 15. C. chromosa.
|1||Bracts distally usually pink to pink-purple; s Idaho, sw Montana, se Oregon, nw Wyoming.||Castilleja angustifolia var. angustifolia|
|1||Bracts distally yellow, yellow-orange, pale orange, white, pink, reddish pink, or magenta; se Idaho, e Nevada, sw South Dakota, w Utah, ec Wyoming.||> 2|
|2||Bracts distally usually yellow to pale orange or white; ec Wyoming, adjacent sw South Dakota.||Castilleja angustifolia var. dubia|
|2||Bracts distally usually yellow, yellow-orange, white, pink, or reddish pink; se Idaho, e Nevada, w Utah.||Castilleja angustifolia var. flavescens|
"acute" is not a number.