Opunita humifusa COSEWIC Status - Endangered plant species in Canada. Opuntia humifusa, commonly known as Eastern Prickly Pear, is a perennial, succulent cactus native to southern Ontario. It was a curious and challenging plant to paint. Found in just two locations in the wild, on the shore of Lake Erie. its segmented pads grow horiizontally or upright across a dry, sandy habitat. Outwardly unfriendly, armed with barbed bristles and sharp spines, Opunita humifusa turns on the charm in June when its exquisite, yellow flowers briefly bloom. A rare endangered plant in Canada, it is widespread in the eastern United States. Note to Editor: "'Opunita humifusa" is the Latin binomial name and should be italicized.