Streptanthus linearifolius A. Gray, Mem. Amer. Acad. Arts, n. s. 4: 7. 1849; Pachypodium linearifolium (A. Gray) A. Gray; Schoenocrambe linearifolia (A. Gray) Rollins; Sisymbrium linearifolium (A. Gray) Payson; S. stenophyllus Rollins; Thelypodiopsis linearifolia (A. Gray) Al-Shehbaz; Thelypodium linearifolium (A. Gray) S. Watson

Perennials. Stems simple or few from caudex, erect, (often much-branched distally), (2.5-)3.5-10(-15) dm. Leaves shortly petiolate; blade usually linear to linear-lanceolate, rarely lanceolate, (2.5-)3.5-12(-15) cm × (1-)2-6(-10) mm (smaller distally), base cuneate to attenuate (or petiolelike), margins entire or, very rarely, sparsely denticulate, apex acuminate to acute. Racemes several-flowered, (proximalmost flowers sometimes bracteate). Fruiting pedicels divaricate or ascending, straight, (5-)8-20(-25) mm. Flowers: sepals purplish, (4-)4.5-7 × 1-2 mm, (median pair apical cuculla to 0.7 mm); petals purple, (10-)12-16(-18) × (2-)3.5-5.5 mm, claw distinctly differentiated from blade, [5-7(-9) mm]; filaments 2-4 mm; anthers narrowly oblong to linear, 2-4 mm; gynophore 0.4-1(-2) mm. Fruits usually straight, rarely curved, terete, (3.5-)4-9(-11) cm × 1-1.5 mm; ovules (76-)80-110 per ovary; style subclavate to cylindrical, 0.5-1.8(-2.5) mm; stigma conical, 2-lobed (lobes prominent, connivent). Seeds 0.9-1.6 × 0.5-0.9 mm. 2n = 22, 44.

Flowering Jul-Nov. Open woods, dry hillsides, oak woodland, mixed conifer forests, arroyos, canyons, rocky ridges, limestone ledges, sandstone crevices, roadsides; 700-3100 m; Ariz., Colo., N.Mex., Tex.; Mexico (Chihuahua, Coahuila, Durango, Nuevo León, San Luis Potosí, Sonora, Zacatecas).