Opuntia robusta Opuntia robusta Opuntia robusta, the wheel cactus, nopal tapon, or camuesa, is a species of cactus in the Cactaceae family. It is native and endemic to central and northern Mexico to within 100 miles of the Arizona and New Mexico borders where it grow from 5,000 to 10,000 feet on rocky slopes, open shrub lands, woodlands and mixed with other cactus and succulents. Plants are commonly around high, though they may grow to over high when supported. The flattened stem segments are fleshy, round and blue-grey in colour. These are up to in diameter and have sharp spines up to
Opuntia bentonii (less inclinded to narrow at the base). "O. bentonii" plants have fewer spines than "O. lindheimeri", zero to 3 (often only 1 or 2). One important difference is that the stigmas of "O. bentonii" flowers are yellow and not green as in "O. lindheimeri." Another individual feature of "O. bentonii" is that the veins are often visible between areoles. Opuntia bentonii Opuntia bentonii was proposed by some botanists to be a synonym of "Opuntia stricta". However, "O. bentonii", which grows in Texas, is separate and distinct from "O. stricta." "O. bentonii" was clearly described by Griffiths in 1911. Along with