Dryopetalon runcinatum

A. Gray

Smithsonian Contr. Knowl. 5(6): 12, plate 11. 1853.

Illustrated
Synonyms: Coelophragmus umbrosus (B. L. Robinson) O. E. Schulz Dryopetalon runcinatum var. laxiflorum Rollins Sisymbrium umbrosum
Treatment appears in FNA Volume 7. Treatment on page 688. Mentioned on page 687.

Annuals or biennials; usually sparsely to densely hirsute proximally, rarely glabrous throughout. Stems erect, unbranched or branched basally, branched distally, 2–8 dm. Basal leaves: petiole (1–)2–6(–8) cm; blade spatulate to obovate in outline, lyrate, pinnatifid, or bipinnately lobed, (2–)4–20(–25) cm × 30–80 mm, surfaces glabrous or hirsute. Cauline leaves shortly petiolate or sessile; blade base not auriculate, similar to basal, smaller distally. Racemes lax or dense. Fruiting pedicels divaricate-ascending, 5–15(–20) mm, glabrous or pubescent. Flowers: sepals (2.5–)3.5–4.5(–5) × 1.5–2 mm; petals white to purplish, spatulate, 6–9(–11) × 2.5–3.5(–4.5) mm, claw 2.5–4(–5) mm, margins pinnatifid, 5–7(–11)-lobed, papillate basally; filaments papillate basally, median pairs 3–5 mm, lateral pair 2.5–4 mm; anthers oblong, 0.7–1 mm. Fruits linear, (straight or arcuate), 2–6 cm × 0.5–1.2 mm; ovules 60–110 per ovary; style 0.1–0.7(–1) mm. Seeds 0.6–0.8 × 0.4–0.6 mm, not winged. 2n = 24.


Phenology: Flowering Jan–May.
Habitat: Ledges, shade of boulders and cliffs, foothills, canyons, scrub woodlands, streambeds, rocky basalt, crevices
Elevation: 800-1900 m

Distribution

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Ariz., N.Mex., Tex., Mexico (Chihuahua, Sinaloa, Sonora).

Discussion

Dryopetalon runcinatum is easily distinguished from other mustards in the flora area by having divided petals. In the United States, it is restricted to Cochise, Pima, Pinal, and Santa Cruz counties in Arizona, Catron, Dona Ana, Hidalgo, and Luna counties in New Mexico, and El Paso County in Texas.

Selected References

None.

Lower Taxa

None.
... more about "Dryopetalon runcinatum"
Ihsan A. Al-Shehbaz +
A. Gray +
Ariz. +, N.Mex. +, Tex. +, Mexico (Chihuahua +, Sinaloa +  and Sonora). +
800-1900 m +
Ledges, shade of boulders and cliffs, foothills, canyons, scrub woodlands, streambeds, rocky basalt, crevices +
Flowering Jan–May. +
Smithsonian Contr. Knowl. +
Illustrated +
Coelophragmus umbrosus +, Dryopetalon runcinatum var. laxiflorum +  and Sisymbrium umbrosum +
Dryopetalon runcinatum +
Dryopetalon +
species +