Oxytheca spergulina (A. Gray) Greene

Herbs, prostrate to spreading or erect, annual, 0.5-4 dm, glabrous or glandular and short-hispid, greenish, grayish, or reddish. Stems: caudex absent; aerial flowering stems prostrate to erect, solid, not fistulose, 0.1-0.5 dm, glabrous or glandular and short-hispid. Leaves basal and cauline; basal: petiole 0.05-0.3 cm, hispid, blade linear, (0.3-)1-3(-4) × 0.05-0.3 cm, short-hispid, margins plane or revolute, ciliate; cauline sessile, blade linear, 0.3-2.5 × 0.05-0.3 cm, similar to basal blade. Inflorescences cymose, open to diffuse, 4-25 × 5-35 cm; branches sparsely hispid to puberulent, internodes usually glandular; bracts 3-6, semileaflike, 2-10 × 0.5-2 mm. Peduncles erect, straight, filiform, 0.4-1.5 cm, glabrous. Involucres turbinate, 0.5-1 × 0.4-0.8 mm, glabrous; teeth 4, erect, 0.2-0.4 mm. Flowers 1.5-3.5 mm; perianth white with greenish to reddish midribs, becoming pinkish to rose, glabrous or sparsely pubescent; tepals monomorphic, oblong; stamens included, 0.5-2 mm; filaments usually glabrous. Achenes brown to blackish, lenticular, 1.5-2.3 mm, glabrous.

Varieties 3 (3 in the flora): w United States.