Sonoran Rainbow Hedgehog

Echinocereus bristolii starts as a single shoot and eventually forms clusters of up to 30 shoots. The light green, cylindrical shoots taper at the tip, growing up to 20 centimeters long and 5 centimeters in diameter. They have 15 to 19 low, sharp ribs that are slightly tuberous. The whitish spines, with darker tips, include three central spines up to 1 centimeter long, with the lower one being the longest, and 22 to 24 radial spines up to 1 centimeter long. The pink, funnel-shaped flowers bloom near the tips of the shoots, measuring 3.8 to 8.5 centimeters in length and 5.5 to 10.5 centimeters in diameter. The nearly spherical fruits split open at the tip.

Echinocereus bristolii is found in Soyopa in the Mexican state of Sonora at elevations between 250 and 1350 meters in scrub and semidesert grasslands. The plant is found growing along with Echinocereus rigidissimus.