Duration: Perennial

Nativity: Native

Lifeform: Vine

General: Slender, twining vine to 3 m long with strigose-cinereous branches.

Leaves: Opposite, linear-lanceolate, 3-7 mm wide, 1.5-4 cm long, upper ones smaller, plane or margins faintly revolute, acute to acuminate, sparsely appressed-pubescent above, somewhat more densely so and slightly paler beneath, 1-10 small marginal glands near base, below calyx.

Flowers: Slender pedicels 2-5 mm long in flowers, 1-1.5 cm long in fruit; sepals ovate-oblong, about 2.5 mm long, glands 0.8-1 mm long; petals yellow, occasionally suffused with red or turning red in age, larger ones 4-5 mm long, blades rhombic or broadly ovate.

Fruits: Coarsely veined samara, wings 9-12 mm long or rarely to 16 mm.

Ecology: Found on rocky hillsides, gravelly slopes, and along arroyos from 1,000-5,000 ft (305-1524 m); flowers April-October.

Distribution: AZ, s NM, s TX; south through c MEX.

Notes: Often climbing over other plants, the opposite linear leaves help to give this plant away, as does the samaras when they are in full expression, often in twos or threes, back to back with the wings pointing outward.

Ethnobotany: Unknown

Etymology: Janusia is of uncertain origin, gracilis means slender or delicate.

Synonyms: None

Editor: SBuckley 2010, FSCoburn 2015