USA, Arizona, Pima County, Las Cienegas National Conservation Area, north-east of Empire Ranch Headquarters by dirt road to Cieneguita cienega.
31.777384 -110.615908
12N 536367E 3515825N Northern
1350 meters (4428ft)
Semi-arid desert grassland with encroaching Prosopis velutina. Red, clay-gravel soils.
Prosopis velutina & grasses.
Uncommon, barrel cactus to 0.75 m tall leaning slightly southward with 31 ribs & 61 green, unripe fruits. Numerous ants at extrafloral nectaries at he base of the fruits. Fresh fruits slightly laterally compressed, 39-44 l x 35-38 mm w.