Opuntia toumeyi Rose, Contributions from the U. S. National Herbarium 12: 402, 1909
Opuntia toumeyi is a low but not prostrate bushy species with pads narrowed towards the base. The plant often appears yellowish-green and has brown or white spines. Glochids are red-brown but may be paler on white-spined plants.
There is often one central spine sticking roughly straight out that is dominant and longer than all the other spines in an areole (sometimes it is missing on some pads but rarely all pads, and sometimes there is more than one). Spination is similar to that in Opuntia flavispina, but the spines are not true yellow; Opuntia toumeyi is often lower and more spreading than Opuntia flavispina. The species is common in the greater Tucson area and has not been observed elsewhere by the authors. Flowers are bright yellow, sometimes with a bit of orange toward the petal bases. The stigmata are green, and the filaments are yellow. See the original citation.