Glabrous or glabrate perennial with thick rootstock and slender stems, sometimes high climbing by means of slender coiling petioles to 7 cm long. Lvs digitate; leaflets 5, sessile or subsessile. Lamina of terminal leaflet (1)-1.5-3.5 × 0.75-1.6 cm, obovate or oblong-ovate, entire, sometimes sparsely hairy below; base narrow-cuneate; apex rounded to emarginate; other leaflets smaller, especially basal pair. Fls solitary; pedicels > lvs, to c. 15 cm long, often purplish. Calyx regular; sepals 5.5-8 mm long, ovate-lanceolate, reddish green, accrescent and deep pink at fruiting; spur 2-3 cm long, curved and tapering, the proximal 1/2 reddish, the distal 1/2 green. Corolla irregular, usually scarlet, occasionally rose; lower 3 petals with very slender claw 7-8 mm long; limb (1)-1.3-1.5 × (1)-1.3-1.6 cm, squarish except for broadly emarginate apex; upper 2 petals c. 1.7 cm long, narrowly cuneate-obovate, broad-emarginate. Anthers green; filaments pink above. Frs thinly fleshy; carpels subglobose, often 1-2 remaining small; fertile carpels 5-7 mm diam., deep or dark blue.