Pl. Hartw., 296. 1849.
Stems (10-)20-50(-90) cm; base reddish, glabrous to puberulent. Leaves mostly on proximal 1/3 of stem; basal leaves 1-3 at anthesis; cauline leaves 2-4 at anthesis; petiole 1.5-12 cm. Leaf blade round to pentagonal, 1-5.5 × 2-7.5 cm, nearly glabrous; ultimate lobes 3-9, less often wedge-shaped, 5 or more extending more than 3/5 distance to petiole, width 5-30(-50) mm (basal), 1-15 mm (cauline), widest at middle or in proximal 1/2. Inflorescences 4-25(-36)-flowered; pedicel spreading from rachis at usually less than 70°, 1-4(-8) cm, glabrous to glandular; bracteoles 3-12(-23) mm from flowers, blue to green, linear, 3-8(-16) mm, glabrous to glandular. Flowers: sepals dark blue, usually retaining color upon drying, glabrous, lateral sepals reflexed, (6-)10-15(-20) × 4-8 mm, spurs straight, ascending ca. 30° above horizontal, 8-18 mm; lower petal blades elevated, exposing stamens, 3-6(-8) mm, clefts 1-3 mm; hairs centered on base of cleft or on inner lobes, scattered, white, rarely yellow. Fruits 12-23 mm, 3.3-3.6 times longer than wide, glabrous or puberulent. Seeds unwinged; seed coats ± pitted, cell surfaces roughened.
Subspecies 3 (3 in the flora).
|1||Lobes of proximal cauline leaves usually more than 15 mm wide; basal and proximal cauline leaves rarely cleft more than 4/5 radius of blade.||Delphinium patens subsp. hepaticoideum|
|1||Lobes of proximal cauline leaves usually less than 15 mm wide; basal and proximal cauline leaves usually cleft more than 4/5 radius of blade.||> 2|
|2||Pedicels puberulent, usually glandular; most leaf blades with more than 7 ultimate lobes.||Delphinium patens subsp. montanum|
|2||Pedicels usually glabrous; most leaf blades with fewer than 7 ultimate lobes.||Delphinium patens subsp. patens|