Arizona lupine (Lupinus arizonicus) is very similar to Coulter's lupine.
It is a pea-shaped flower that spirals around a hairy flower spike.
Individual flowers are pink, or pinkish purple,
as opposed to blue in Coulter's lupine, and the flower has a red-spotted, yellow and white banner spot that becomes deep magenta with age
(as opposed to a brown spotted, yellow and white banner spot in Coulter's lupine).
The leaves have 6 to 10 leaflets and the upper surface is hairless, unlike Coulter's lupine which has hair and which has narrower leaflets.
These Arizona lupine were photographed off the I-10 freeway outside of Quartzite, Arizona.