Texas barrel cactus

Echinocactus hamatacanthus Muehlenpfordt, Allg. Gartenzeitung 14: 371. 1846 (as hamatocanthus)

Stems erect, spheric to short cylindric, 10-63 × 7.5-30 cm; ribs 10-17, crenate or sharply notched to undulate or deeply sinuate, hence ribs prominent to poorly defined, or stem sometimes tuberculate. Spines 12-16(-28) per areole, pinkish brown and/or straw colored, often imparting appearance of dried grass clump, smallest spines per areole slender, sometimes bristlelike, less than 1 mm diam.; central spines 4(-8) per areole, terete to strongly flattened, apically curved or strongly hooked, very flexible, sometimes almost papery, smooth to weakly annulate, principal central spine (40-)60-165 × (0.5-)1-3 mm. Flowers yellow inside and out, 5.5-8(-10) × 6.5-9.5 cm; inner tepals bright lemon yellow, very glossy; stigma lobes pale yellow. Fruits indehiscent, green or maroon, 20-50 × 10-30 mm, thin walled, soft, juicy, locule filled with very juicy pulp and seeds. Seeds 1-1.6 mm, pitted.

Varieties 2 (2 in the flora): sw United States, n Mexico.