Leaves: petiole 0–5 mm; blade broadly ovate or oval to orbic­ulate, 3–7 × 2–6 cm, apex rounded to obtuse, venation eucamptodromous to faintly brochidodromous, surfaces sparsely strigose on midvein abaxially. Inflorescences 4–10-flowered. Pedicels (15–)25–35 mm. Flowers: calyx lobes 7–8 mm; corolla lobes 11–14 mm; fused anthers dark brown, 2–3 mm; corona segments red-violet, 6–8 mm, apices (including recurved tooth) exceeding style apices.

Phenology: Flowering Apr–Jul; fruiting May–Jul.
Habitat: Ridge tops, mesas, slopes, flats, arroyos, canyons, plains, alluvium, sandstone, shale, gypsum, limestone, granite, ash, sand, silt, clay, or calcareous soils, juniper, pinyon-juniper, and oak woodlands, shrubby grasslands.
Elevation: 1300–2700 m.

Distribution

• Generated Map
• Legacy Map

Ariz., Colo., Nev., Utah, Wyo.

Discussion

Subspecies cryptoceras co-occurs with and, in vege­tative morphology, is remarkably similar to Astragalus asclepiadoides (Fabaceae), Cycladenia humilis (Apocyn­aceae), and Mirabilis multiflora (Nyctaginaceae). One cannot help but speculate that they form a mys­terious mimicry complex. Subspecies cryptoceras is rare in Arizona (Coconino, Mohave, and Navajo counties) and Nevada (Lincoln and Nye counties).

Selected References

None.

Lower Taxa

None.