Cologania angustifolia
A purple-flowered, four-sepalled vine found in the U.S. in much of Arizona & southeastward to the Big Bend region of Texas. The leaves are, as the name suggests, narrower than in C. broussonettii.
A flower on Georgetown Road in the eastern Pinos Altos Range, Grant Co., NM, 29 Aug 2009.
Side view of the same flower, Georgetown Road, 29 Aug 2009.
Leaves on Georgetown Road, 29 Aug 2009.
Immature fruit on Georgetown Road, 29 Aug 2009.