Aristolochia watsonii

Herbs, procumbent, to 0.5 m. Young stem smooth, glabrous. Leaves: petiole 0.4-1 cm. Leaf blade lanceolate, 8 × 5 cm, base strongly sagittate, sinus depth 0.5-2 cm, apex acuminate to acute; surfaces abaxially tomentose to tomentulose; venation pinnate. Inflorescences on new growth, axillary, solitary flowers; peduncle bracteolate, to 1 cm; bracteoles lanceolate, to 6 mm. Flowers: calyx brown-purple, straight to curved; utricle angled upward, ovoid to narrowly ellipsoid, 0.6-0.7 × 0.5 cm; syrinx tubular, 1.5 mm; tube angled upward, cylindric, 1 × 0.3 cm; annulus absent; limb orangish with maroon spots, 1-lobed, lobe ovate, 1-6 × 0.6 cm, pilose; gynostemium 5-lobed, crown-shaped, 1-4 mm; anthers 5; ovary 5-locular, to 1 cm. Capsule ovoid to obovoid, 1.5 × 1-2 cm, dehiscence acropetal; valves 5; septa entire, not attached to valves. Seeds flat, triangular, 0.3-0.4 × 0.4 mm.

Phenology: Flowering spring–summer.
Habitat: Rocky slopes
Elevation: 50-1000 m

Ariz., N.Mex., Mexico.

Discussion

Selected References

None.

Lower Taxa