24. Streptanthus longisiliquus G. L. Clifton & R. E. Buck, Madroño 54: 94. 2007. TYPE: United States, California, Butte Co., ca. 0.8 km N of Robley Point, steep raod bank, 39°52′21˝N, 121°31′06˝W, 13 Jun 1997, G. Clifton 35529 (holotype, JEPS; isotypes, CAS, CHSC, MO!, NY!, PUA, RSA).
Herbs, perennial, short lived, glabrous throughout except for sepals and sometimes petioles, glaucous; caudex simple or few branched. Stems 2.2–12(–15) dm, few branched. Basal leaves rosulate in juvenile plants, with glabrous or rarely ciliate petioles, obovate to spatulate, 3.5–10 cm; middle cauline leaves broadly oblong to ovate or suborbicular, 2.5–10 x 1–3.5 cm, sessile, amplexicaul, entire, not overlapping; upper leaves smaller in size, reduced. Racemes ebracteate, lax, without a terminal cluster of sterile flowers; fruiting pedicels divaricate-ascending, straight, 5–10 mm. Flowers: sepals forming subcampanulate calyx, yellow greenish proximally, purple distally, oblong, 6–8 mm, not keeled, with a subapical tuft of hairs; petals with yellow-green claws and purple to brownish blades, 8–12 mm; blade not crisped, 1–3 x 0.5–0.8 mm; claw 6–10 mm, wider than blade; filaments in 3 pairs of unequal length, free; adaxial pair 7–10 mm; abaxial pair 6–8 mm; lateral pair 4–6 mm; anthers of all stamens fertile, 3.5–5 mm. Fruits 5–13(–15) cm x 2–2.5 mm, arcuate, descending, flattened, not or only slightly torulose; valves glabrous, with distinct midvein; gynophore 0.3–1 mm; replum straight; style 1.5–3.5 mm; stigma entire; ovules and seeds 50–82 per fruit. Seeds oblong, 2.2–3 x 1.4–1.8 mm; wing continuous, 0.1–0.4 mm wide.
Habitat: openings in pine forests, oak woodland.
Elevation: 400–1700 m.
Distribution: United States (California/Butte, Shasta, and Tehama counties).