Delphinium nuttallianum Pritzel var. lineapetalum (Ewan) C. L. Hitchcock

Stems (15-)30-60 cm; base usually reddish, glabrous to glaucous. Leaves basal and cauline; basal leaves absent at anthesis; cauline leaves 2-5 at anthesis; petiole 0.2-8 cm. Leaf blade round, 1-5 × 2-6 cm, glabrous; ultimate lobes 5-16, width 1-4 mm (basal), 0.5-3 mm (cauline). Inflorescences (3-)9-24(-40)-flowered, pyramidal; pedicel spreading, 1-2.5 cm, glabrous or glandular-puberulent; bracteoles 4-7 mm from flowers, blue or green, linear, 1-3 mm, glabrous or glandular-puberulent. Flowers: sepals light blue to lavender, nearly glabrous, lateral sepals reflexed, 10-13 × 3-5 mm, spurs straight to slightly decurved, nearly horizontal to ascending ca. 30° 11-17 mm; lower petal blades elevated, exposing stamens, 3-5 mm, clefts 0.5-2 mm; hairs centered mostly on inner lobes near base of cleft, white. Fruits 13-21 mm, 4-4.5 times longer than wide, puberulent to glabrous. Seeds: seed coat cells narrow, short, cell margins straight, surfaces smooth.

Flowering spring. Open pine woods, dry meadows; of conservation concern; 400-1800 m; Wash.