Cactus fire

A small brownish-gray butterfly with long legs and long antennae. Fore wings with a pattern of characteristic stripes, hind wings whitish. The wingspan of females is 27–40 mm, and that of males is 23–32 mm ^[1] .

Caterpillars of the first ages are pink-cream in color, with age their color turns orange with black spots or stripes.

Butterflies are active at dusk, mainly in the wee hours. They do not feed and live off the nutrients accumulated in the caterpillar stage ^[2] . The life expectancy of adults is up to 9–11 days ^[3] . Males fly in search of females for mating. The female lays 30 to 50 eggs on fodder plants ( cacti ) ^[2] . The duration of the egg stage is 25-30 days ^[2] . Caterpillars of the first ages live in groups. They dig holes in the cactus trunks, and then feed on them. Ultimately, the caterpillars gnaw through the cactus from the inside. The caterpillar stage lasts about 2 months in the summer months and about 4 months in the winter ^[2] . Pupation takes place in a cocoon on the ground in the litter at the base of the feed plant ^{[2] [3] [4]} .

The historical natural range included the territory of such countries as: Argentina , Paraguay , Uruguay and southern Brazil . It is one of the five species of the genus Cactoblastis in South America ^[5] .

Introduction

The species has been introduced in many regions of the world. A cactus fire was first introduced to Australia in 1925 from Argentina as a biological agent for controlling cacti of the genus Opuntia . Due to the success of introducing the species in Australia, it has also been introduced to many other regions around the world, including South Africa in 1933 and the Caribbean in the 1950s ^{[3] [6]} .

Introduced cactus species have become dangerous weeds in the well-known case of Australia . In 1832, cacti of the genus Platyopuntia were used as hedges north of Sydney, and in 1839 a single copy of the Opuntia stricta species was introduced into Sydney as an ornamental plant. This species was naturalized and spread by pieces of treasures , including when plowing land. Birds also spread seeds. In 1914, a collection of various prickly pear cactus was brought to Australia. By 1925, thickets of cactus-prickly pear cacti of the species Opuntia large-thorned , Opuntia stricta and Opuntia vulgaris occupied an area of ​​up to 24 million hectares of pasture and became a real disaster for local farmers. To combat them, a natural enemy of the prickly pear was brought to Australia - a cactus flint (Cactoblastis cactorum). The species was introduced in 1925 from Argentina ^[6] . The biological cactus control program was launched in the Australian town of Bunarg, where in 1926 an introduction of a cactus fire was launched at the Cactoblastis experimental station. Thanks to these measures, the opuntia population was able to be taken under control. Prickly pear is not completely destroyed in Australia, due to the caterpillars of the cactus fire, an ecological balance has arisen ^[7] .

In 1938, in the Darling River Valley, Dalby , Queensland, Australian farmers erected a monument to the caterpillars that "saved" Australia from the prevalence of prickly pears ^[8] .

After introduction into the Caribbean , a cactus flare was inadvertently brought in with ships and cargoes to St. Kitts , the US Virgin Islands , Haiti , Cuba , Dominica , the Bahamas , Cayman Islands , Puerto Rico and Barbados . This created the prerequisites for the possibility of settling the species in the southeastern United States, where it was first discovered in Florida in 1989 . A cactus fire was probably brought to Florida along with cacti of the genus Opuntia from the Dominican Republic . Currently, the butterfly is actively settled moving on both sides of the Gulf of Mexico and along the American coast of the Atlantic Ocean at a speed of about 160 kilometers per year, and the speed of colonization along the coast of the Gulf of Mexico is increasing every year ^[3] . In the USA, a cactus fire threatens prickly pear cacti in Florida, on the Atlantic coast, in South Carolina and in New Orleans ^[3] .

Spreading in the southeastern United States, it threatens many cactus species and many ecosystems. In Florida, several species of endangered cacti are most vulnerable ^[9] . Modern research is being done to identify the most effective ways to prevent the invasion of a species in a local cactus population. Cacti are grown in the United States for sale as ornamental plants in Arizona , California , Nevada , New Mexico and Texas .

A cactus flare also spread across the Gulf of Mexico in Mexico, where it was first discovered on Isla Mujeres off the northeast coast of the Yucatan Peninsula . It is not known how the species was able to migrate to Mexico. However, presumably, this was made possible thanks to winds, hurricanes and unintentional delivery. Recently, a cactus fire has begun to harm cacti on the island of San Salvador in the Bahamas . Here, prickly pears are the main food source for the genus iguanas Cyclura ^[9] .

In the future, researchers predict a westward expansion of the species range in North America ^[9] . This westward expansion threatens cactus-related industries in the southwestern United States and in the interior of Mexico . In North America, more than sixty species of prickly pear are growing, which are a vital part of the ecosystem. The fruits of prickly pear are a major part of the diet of the local population, mainly in Mexico. In addition, in Mexico, cacti serve as an alternative food for livestock during droughts, and many of the various prickly pear prickly pear cacti are the basis for the cochineal industry ^{[9] [10]} . The destruction of these cacti would have a serious impact on the economy and ecology of Mexico ^[9] .