Stems scrambling to climbing, 2-3 m. Leaf blade 1-2-pinnate, usually 5-foliolate, sometimes proximal and lateral leaflets also 3-foliolate; leaflets ovate to lanceolate, usually 3-lobed, 1-3.5 × 0.7-3.2 cm, membranous to leathery, margins each usually with 1-3 acute to rounded teeth, rarely entire; surfaces glabrous or very sparsely silky. Inflorescences axillary, 3(-12)-flowered cymes or flowers solitary or paired. Flowers unisexual; pedicel slender, 1-3.5 cm; sepals wide-spreading, not recurved, white to cream, obovate to oblanceolate, 7-12 mm, abaxially pilose to silky, adaxially glabrous; stamens 30-50; staminodes absent or fewer than stamens; filaments glabrous; pistils 20-50. Achenes broadly ovate to nearly orbiculate, 4-4.5 × 2.5-3.5 mm, conspicuously rimmed, glabrous; beak 2.5-4 cm.
Flowering winter-fall (Jan-Oct; usually Mar-Apr). Dry chaparral, edges of meadows and cultivated fields; 0-2200 m; Calif.; Mexico (Baja California).
Clematis pauciflora is a distinctive species easily identified by the small, 3-lobed leaflets, glabrous or almost glabrous leaves and stems, and large, suborbicular achenes. Intermediates between C. pauciflora and C. lasiantha are present where the two species occur together.