Peniocereus greggii var. greggii
Areoles elliptic, 4–5 × 2 mm; adaxial spines tending to be directed toward tip of plant; abaxial (including abaxial lateral) spines directed toward base of plant. Flowers 15–17 × 5–6 cm.
Phenology: Flowering late spring; fruiting summer.
Habitat: Chihuahuan Desert, sandy or gravelly loams, along washes, on creosote bush flats or gentle slopes
Elevation: 1200-1500 m
Ariz., N.Mex., Tex., Mexico (Chihuahua, Coahuila, Durango, Sonora, Zacatecas).