Opuntia echios Opuntia echios Opuntia echios is a species of plant in the Cactaceae family. It is endemic to the Galápagos Islands (Ecuador) and is commonly known as the Galápagos prickly pear, but there are five other species of prickly pears that also are endemic to the archipelago ("O. galapageia", "O. helleri", "O. insularis", "O. megasperma" and "O. saxicola"). There are five varieties of "Opuntia echios", each with a different appearance and distribution: "Opuntia echios" var. "echios" on the islands of Santa Cruz, Baltra, Daphne Major and South Plaza, "Opuntia echios" var. "barringtonensis" on Santa Fe, "Opuntia echios" var. "gigantea" near Academy
Opuntia ficus-indica the wild origin of "O. ficus-indica" is likely to have been in Mexico due to the fact that its close genetic relatives are found in central Mexico. "Opuntia ficus-indica" is polyploid, hermaphrodite and autogamous. As "Opuntia" species grow in semi-arid environments, the main limiting factor in their environment is water. They have developed a number of adaptations to dry conditions, notably succulence. The perennial shrub "Opuntia ficus-indica" can grow up to 3-5m height, with thick, succulent and oblong to spatulate stems called cladodes. It has a water-repellent and sun-reflecting waxy epidermis. Cladodes that are 1–2 years old produce flowers, the