New Mexico Beeblossom
Oenothera coloradensis subsp. neomexicana
(Gaura neomexicana)

Family: Evening Primrose (Onagraceae)
AKA:
Photo taken on: September 7, 2013
Location: Rio Chama, Abiquiu, NM
Life Zones: Plains and foothills
Habitat: 20 feet from the river on dry ground

Grows 2 to 3 feet high with several reddish stems. Leaves are lance-shaped with wavy edges. Flowers are about ½" across and have four white petals with four reddish hairy sepals below. Flowers grow in clusters at the end of branches but only a few flowers are open at one time.

This matches the description of the threatened Colorado Beeblossom (ssp. coloradensis) which is endemic to the Colorado/Wyoming border.