Perennial; stems stout, ascending, often purplish tinged; leaves pinnately compound, mostly 15-29 foliate, 4-18 cm long; leaflets 5-20 mm long, elliptic to ovate, flat, pubescent on both surfaces, hairs straight, lying flat against the leaf surface; racemes 10-30 flowered; flowers pea-like, 16-24 mm long; petals pinkish-purple when fresh, drying bluish; pods spreading or ascending, oblong, usually straight and plump, 25-50 mm long, 2-chambered, becoming thick, spongy, and bright red when ripe. Flowers March to May.
This is the only milkvetch with pinkish-purple flowers and large, thick, bright red pods that grows on gypsum soils.
New Mexico, Eddy County, Yeso Hills; adjacent Texas.
Gypseous soils in Chihuahuan desert scrub; 1,050-1,125 m (3,500-4,000 ft).
Not significantly threatened by the current land uses within its habitats. County road and state highway projects could remove some plants. Gypsum mining is a minor potential threat, if conducted on a large scale.
*New Mexico Native Plants Protection Advisory Committee. 1984. A handbook of rare and endemic plants of New Mexico. University of New Mexico Press, Albuquerque.
Barneby, R.C. 1956. Pugillus Astragalorum XVII. American Midland Naturalist 55:499-500.
Isely, D. 1998. Native and naturalized Leguminosae (Fabaceae) of the United States. Monte L. Beane Life Science Museum, Brigham Young University, Provo, Utah.