Convolvulus aridus Greene subsp. tenuifolius Abrams, Contr. Dudley Herb. 3: 359. 1946

Herbage glabrous or puberu­lent. Stems trailing or weakly twining-climbing. Leaf blades linear to narrowly triangular, 1–7 mm wide, excluding lobes, basal lobes linear, 2-pointed or rounded, basal sinus rounded to quadrate, apex acute. Bracts narrowly lanceolate, 8–14 × 4–8 mm, proximally flat or ± keeled, apex acute. Flowers: sepals 7–10 mm; corolla white or cream, 22–30(–40) mm; stamens 13–18 mm.

Flowering Apr–Sep. Canyons, rocky hillsides, shrubby sites; 0–1400 m; Calif.; Mexico (Baja California).

Subspecies tenuifolia intergrades with Calystegia longipes and with C. macrostegia subspp. arida and intermedia.