Native to the Southwestern United States and Northwestern Mexico about 30 species. Large barrel-shaped cacti, mostly with large spines and small flowers. Stems are ribbed, mostly straight, sometimes tuberculate. All species have stout spines, some of them especially thick and heavy and may be hooked or straight. Spines come in a wide range of colors, often varying within species, and may be yellow, gray, white, brown, pinkish, or most notably, red. Flowers come from the top of the plant, often forming a right around the apex. Colors of flowers are either yellow to red and are funnel-shaped openings. Summer growers need bright light to filtered light. Well-drained soil is required.