Opuntia aurantiaca by the larvae of two moths, "Cactoblastis cactorum" and "Tucumania tapiacola". Opuntia aurantiaca Opuntia aurantiaca, commonly known as tiger-pear, jointed cactus or jointed prickly-pear, is a species of cactus from South America. The species occurs naturally in Argentina, Paraguay and Uruguay and is considered an invasive species in Africa and Australia. It was declared a Weed of National Significance by the Australian Weeds Committee in April 2012, and was reported by the Committee to be the most troublesome of all cactus species in New South Wales and the worst Opuntia species in Queensland. It is currently controlled biologically in Australia
Opuntia arenaria strongly deflexed and much shorter. Overall, plants (clumps) of cladodes may be 20–30 cm across and about 4–8 cm tall. Fruits are small, about 2.5 cm. Opuntia arenaria Opuntia arenaria was considered a variety of "O. polyacantha" by many botanists, and is still treated that way in the Flora of North America. However, "O. arenaria" is diploid and "O. polyacantha" is tetraploid. It was described by Engelmann in 1856. "Opuntia arenaria" can grow in soil that is essentially pure sand. It has rhizomes up to 1.5 m long that give rise to above ground shoots with small cladodes that are