1. Opuntia pusilla (Haworth) Haworth, Syn. Pl. Succ. 195. 1812.
Cactus pusillus Haworth, Misc. Nat., 188. 1803; Opuntia drummondii Graham; O. tracyi Britton
Shrubs, creeping, often forming mats, trailing, to 0.1 m. Stem segments easily detached, green, purplish red under stress, flattened, elliptic to linear, sometimes subcylindric (to subspheric), 2.5-5(-8) × 1.2-2.5 cm, tuberculate, glabrous; areoles 2-5 per diagonal row across midstem segment, subcircular, 2-3 mm diam.; wool tan to gray. Spines (0-)1-2(-4) per areole, in distal 3/4 of stem segment areoles (to nearly spineless), porrect to spreading, red-brown, aging gray, stout, straight, terete, to 30 mm, strongly barbed. Glochids in crescent at adaxial edge of areole, pale yellow, aging brown, to 3 mm, longest at areole apex. Flowers: inner tepals yellow throughout, 20-30 mm; filaments and anthers yellow; style and stigma lobes white. Fruits green becoming red-purple at late maturity, barrel-shaped, 18-30 × 12-20 mm, fleshy, glabrous, spineless; areoles 8-16. Seeds tan, subcircular, flattened, 4-6 mm diam.; girdle slightly protruding. 2n = 44.
Flowering spring (Apr-May). Dune and pine scrub, primarily coastal, sandy openings, dunes, or rocky outcrops; 0-100 m; Ala., Fla., Ga. , Miss., N.C., S.C., Tex.