Shrubs, 1–3 m, twigs strigulose-tomentose. Leaves: rachis 3–7 cm; leaflets 5–11, blades lanceo­late to elliptic, 1–2.5(–4) × 0.4–1.3 cm, base cuneate to rounded, apex acute, apiculate. Racemes 2–8-flowered, congested, 2.5–4 cm; bracts lanceolate, apex acute. Pedicels 2–5 mm. Flowers ascending, 16–24 mm; calyx obconic, 10–11(–15) mm; corolla usually purple or lilac, rarely white. Legumes tan, torose, straight to slightly curved, compressed, oblong, 5–10(–12) × 1–1.4 cm, papery to almost leathery. Seeds 3–7(–10), dull red to reddish brown, 7–11 mm. 2n = 18.

Phenology: Flowering Mar–May.
Habitat: Limestone soils, foothills, des­ert washes, canyon slopes, with creosote bush, pinyon, juniper, oak, yucca.
Elevation: 700–1600 m.

Distribution

• Generated Map
• Legacy Map

Ariz.

Discussion

Dermatophyllum arizonicum is known from Graham, Mohave, and Yavapai counties. This species, D. guadalupense, and the Mexican D. gypsophilum (B. L. Turner & A. M. Powell) Vincent, D. juanhintonianum (B. L. Turner) B. L. Turner, and D. purpusii (Brandegee) Vincent, form a closely related group (M. Izaddoost 1975; D. K. Northington 1976; V. E. Rudd 1972; B. L. Turner 2012). D. Isely (1981) suggested that some of these taxa may not deserve recognition as distinct species.

Selected References

None.

Lower Taxa

None.