Botanical Name : Opuntia elatior Mill.
Family : Cactaceae
O. elatior, commonly known as the red flower prickly pear, is one of many invasive Opuntia cacti but is less widespread than most. It is native to northern South America, southern Central America and the southern Lesser Antilles. It was introduced to Indonesia, India and South Africa in the 1800s where it quickly spread. Control of O. elatior in India and Indonesia in the early 1900s was one of the first successes of biological control indicating that it could be effectively controlled elsewhere. As it is dispersed easily by birds and capable of forming dense thickets O. elatior is considered a potential environmental weed or ‘sleeper weed’ in Australia in semi-arid areas and drier coastal habitats.
P. elatior is shrubby or arborescent, forming dense, much branched clumps or plants with a well-defined primary trunk up to 5 m tall. Cladodes are olive green and oblong shaped, 10-40 cm long. Flowers are yellow-orange with red stripes or totally orange-red, the style is expanded at the base forming a nectary, the filaments are reddish-pink, and the stigma lobes are green. Fruit is egg shaped as with most opuntias, and reddish to reddish-pink when ripe; the outer surface of the fruit is typically tuberculate, as a result of the raised areoles; small spines may develop from the areoles of the fruit. Spines are clustered in groups of two to eight, each 2-4 cm long, needle-like and bright white aging darker grey to brown (Government of Australia, 2015).
The native distribution of O. elatior is disputed. It is certainly native to Colombia and Venezuela, but records from Panama and Costa Rica are questioned, and Caribbean islands may be more recent introductions. However, the broader native range limits according to Hunt et al. (2006) and USDA-ARS (2014), are Colombia, Venezuela, Panama, and the Caribbean (Netherlands Antilles and Lesser Antilles).
In Colombia, it has been reported in the semi-arid Andean region of La Tatacoa in Huila Department (Figueroa and Galeano, 2007), and in the state of Bolivar in Venezuela (Ponce, 1989; Díaz and Chitty, 2007). In the Caribbean, USDA-ARS (2014) records the islands of Curacao and Saba (Netherlands Antilles), Montserrat, and Redonda (Antigua and Barbuda). Missouri Botanical Garden (2014) includes records from Venezuela, Colombia, Panama and Costa Rica.
Majure et al. (2013), however, dispute the distribution in Central America and the eastern Lesser Antilles. Although a few individuals or small populations have been recorded in Palo Verde National Park, Costa Rica (Chavarría et al., 2001) it is clear that the species was misidentified and actually is Opuntia lutea (Hammel, 2000; LC Majure, Desert Botanical Garden, Arizona, USA, personal observation). The Panama record is also noted as improbable by Majure et al. (2013), but they include it in the native range list: Colombia; Venezuela; Panama; Aruba and Bonaire (Netherlands Antilles); Saba, Sint Eustatius and Sint Maarten (Netherlands Antilles) in the Lesser Antilles.
O. elatior has been introduced in Australia, India and Java, Indonesia and also to South Africa, Thailand and Ascension Island (Royal Botanic Gardens Kew, 2014). This species is scattered throughout southern and central Australia (Weeds of Australia, 2014), in southeastern Queensland, southern Northern Territory, some parts of South Australia and New South Wales, and Victoria. It is also noted that “its distribution may be more widespread than herbarium collections would indicate (e.g. there are also reports that it is naturalized on offshore islands in Western Australia)” (Weeds of Australia, 2014). The Council of Heads of Australasian Herbaria (2014) map of distribution in Australia notes a concentration of reports from southeastern South Australia, and isolated records from Western Australia, Queensland and New South Wales.
O. elatior is not browsed by sheep, but if cladodes (stem fragments) are burned to remove the spines, chopped and sun-dried, they could be used as a component of feed supplements (Tien and Beynen, 2005).
O. elatior is an important alternative material for Venezuelan agro-alimentary industry. Pulp has been assessed as part of a stability evaluation of citric beverages pigmented with natural sources of betalains.
O. elatior is grown and sold as an ornamental plant. It is also reported to have been planted in Java, Indonesia as a boundary and barrier/support.
P. elatior is an important plant used as medicine due to beneficial health promoting properties. The fruits are used in several indigenous systems of medicine for the treatment of various ailments, including anaemia, asthma, inflammatory disorders and diabetes. The speedy and progressive recovery of anaemia in the treatment of prickly pear may be due to increased erythropoiesis and/or antioxidant property of betacyanin.