Bot. California 1: 573. 1876.
Herbs, annual, 2–10 (–15) dm; with a short taproot or small, fibrous-root system. Stems solitary or few, erect, unbranched, rarely branched distally, hairs sparse to dense, spreading, sometimes shaggy (var. minor), short to long, soft to stiff, eglandular and/or sparsely to densely stipitate-glandular. Leaves green or purple to ± gray, linear to lanceolate, 2–10 cm, not fleshy, margins plane, sometimes wavy, ± involute, 0-lobed, apex acuminate to acute, sometimes obtuse. Inflorescences 5–40 × 1–4 cm; bracts proximally greenish, distally red, red-orange, or pale orange, rarely yellow, on apices, narrowly lanceolate, sometimes narrowly oblong to spatulate distally, 0-lobed, plane-margined, apex acuminate (oblong to narrowly spatulate in var. spiralis). Calyces green or yellowish green, 13–27 (–28) mm; abaxial and adaxial clefts 6–15 mm, 33–75% of calyx length, deeper than laterals, lateral 0.5–4 mm, 5–20% of calyx length; lobes linear to narrowly triangular or narrowly lanceolate, apex acute or acuminate. Corollas straight, 13–39 mm; tube 11–16 (–20) mm; beak partially to completely exserted, sometimes included, adaxially yellow, pale orange to red-orange, reddish-brown, green, or white, 5–15 (–20) mm; abaxial lip yellow, white, red, deep red, red-violet, or green, colored as or strongly contrasting with rest of corolla, small but jutting out at 90° from axis of corolla, often readily visible through abaxial cleft, 1–3 mm, 5–25% as long as beak; teeth spreading to strongly incurved, green, white, yellow, red, or red-purple, 0.2–1 mm. 2n = 24.
B.C., Ariz., Calif., Colo., Idaho, Mont., N.Mex., Nev., Oreg., Utah, Wash., Wyo., nw Mexico
Varieties 4 (4 in the flora).
Castilleja minor is a widespread specialist of seeps, saline shores, and wet ground at moderate elevations. California has many populations on serpentine substrates. Most of the varieties have distinct ranges with little overlap, with the exception of the edaphic obligate var. spiralis, which is restricted to serpentine substrates.
|1||Corolla beaks 5–8(–10) mm, usually 1/3 or less of length of corollas, included to more often partially exserted from calyces.||> 2|
|2||Abaxial lips of corollas red to reddish purple; leaves linear or linear-lanceolate, soft; mountains of c, e Arizona and adjacent New Mexico southward.||Castilleja minor var. minor|
|2||Abaxial lips of corollas whitish, pale green, or pale yellowish; leaves linear-lanceolate to lanceolate, coarse; widespread in Great Basin region.||Castilleja minor var. exilis|
|1||Corolla beaks 8–15(–20) mm, usually 1/3+ of length of corollas, exserted from calyces.||> 3|
|3||Proximal bracts narrowly lanceolate or oblanceolate, distals oblong to narrowly spatulate, apices rounded or obtuse, rarely acute; abaxial lips of corollas red.||Castilleja minor var. spiralis|
|3||Bracts linear to narrowly lanceolate, apices acuminate; abaxial lips of corollas whitish, rarely greenish or pale yellow (sometimes red in c Arizona).||Castilleja minor var. stenantha|