Plants annual, succulent, glab-rous, glaucous. Stems nearly prostrate, radiating pseudo-verticillately from base, 10-20 cm. Leaves appearing whorled; not stipulate; petiole 2-8 mm; blade ovate to suborbiculate, (0.2-)0.5-1.3 cm × 4-10 mm, base obtuse to rounded, apex ± obtuse. Inflores axillary, congested, 3-12-flowered umbelliform clusters. Pedicels shorter to longer than subtending bracts at maturity. Flowers: sepals with 3 or 5 obscure veins usually not confluent apically, oblong to broadly elliptic (herbaceous portion similar), 2-3.5 mm, subequal, apex obtuse (herbaceous portion generally acute), not hooded, glabrous; petals 4-fid for 2 or less their length, 2.5-3 mm, 2/ 3-1 times as long as sepals, lobes 1-veined, vein unbranched, linear, outer pair 1/ 2 length of petal, each with narrower, slightly shorter lobe on inner flank, trunk laterally denticulate, base abruptly tapered, apex ± rounded. Seeds olive green to black, teardrop-shaped (with elongate or crescent-shaped lateral thickening), 1.1-1.3 mm; tubercles marginal, minute, elongate.
Flowering spring-late summer. Heavy, saline soils, desert flats, river bottoms, playa margins; 1200-1500 m; Ariz., N.Mex., Tex.; Mexico (Chihuahua, Coahuila, Durango, Nuevo León).
Drymaria pachyphylla is highly toxic to livestock.