Aristolochia watsonii  Desert Pipevine
PERENNIAL.  Long-lived; sprouts from a thick, gnarled taproot.  Very dark purplish or blackish green arrow-shaped leaves. Curved vase-shaped flowers appear after rain.  Oval, ribbed capsules hold many triangular black seeds.  Dies back in winter. Food plant for the Pipevine Swallowtail butterfly.  Occasional throughout the Empires in gravel washes or coarse sand among boulders.
FAMILY:  Aristolochiaceae  (Pipevine Family)