Opuntia ficus-indica a fruit crop, and also for the vegetable nopales and other uses. Most culinary references to the "prickly pear" are referring to this species. The name "tuna" is also used for the fruit of this cactus, and for "Opuntia" in general; according to Alexander von Humboldt, it was a word of Taino origin taken into the Spanish language around 1500. Cacti are good crops for dry areas because they convert water into biomass efficiently. "O. ficus-indica", as the most widespread of the long-domesticated cactuses, is as economically important as maize and blue agave in Mexico. Because "Opuntia" species hybridize easily,
Opuntia basilaris These are more or less blue-gray, depending on variety, long and less than wide and thick. They are typically spineless, but have instead many small barbed bristles, called glochids, that easily penetrate the skin. "Opuntia basilaris" blooms from spring to early summer. The species is variable in nature and several names under different ranks have been described. Only four of these are generally accepted. Some experts consider the Trelease's beavertail to be a full species (Bowen 1987, R. van de Hoek). It is unique among the varieties of "Opuntia basilaris" in that the areoles contain spines in addition to the