Not all ladybugs bring good luck, especially to their similar. Of the 5000 species cataloged, man of them struggle each other for domination of the area, reaching cannibalism to conquer the territory.
The entomologists call it the “War of the ladybugs,” a phenomenon that in recent years has attracted attention. One of the most famous species, the Coccinella septempunctata, the one with seven black dots on the red back risks to disappear.
To unseat this insect is its Asian cousin, Harmonia axyridis or the “Harlequin Ladybug”, more durable and quick to reproduce.
All ladybugs are voracious and combative, able to devour in a single day, as adults, up to 277 soybeans aphids or 207 larvae.
The septempunctata is the most famous star of songs, cartoons and commercial logos but its nice look should not be misleading, since it is one of the few insects that kill the prey before devouring her, just like cats.
The only one that could actually destroy it is the Harlequin Ladybug, even more terrible who lives with no enemies in an undisputed territory ranging from Kazakhstan to Japan.
Europeans, in the mid-90s, have made the serious mistake to introduce it in France, Belgium and Holland as a tool – very effective, it must be said – of biological control. Harmonia axyridis is now the ladybug that reproduces faster in the world and is gradually eliminating the other species.
It lives in a range that is extended from Denmark to southern France and from Great Britain to the Czech Republic, but for some mysterious reason, despite having been released in Greece, Spain, Portugal and the Azores Islands, does not seem to appreciate Southern Europe, as well as the south of Italy.
The higher risk is at the continental level: as explained on Diversity and Distributions the “ladybugs war”could lead to extinction, within a short time, the European species, just as happened in the ’70s, to the American one, brought to its knees by the exuberance of” septempunctata. ”
It is not difficult to distinguish our local ladybug from the Asian one. “The first – explains the biologist Lisa Master – is a bit ‘larger (up to 8 mm long) and on the back has a variable number of dots, while the elytra (the colered wings) are often not red but yellow or orange (or black, with two or four red dots) and is the variable color to them did gain the nickname “harlequin.”
On “pronotum” (the front part of the thorax that in our ladybug is almost always black) has two large white spots and black draws an “M” or “W”, depending on which side you look at it. The larva, which in all species is a spiny caterpillar, is black, with orange stripes on the sides, while it is gray with little orange dots in this case to seven points ladybug. ”
The Harlequin ladybug also ruin the vine production so is dangerous for all the country that produce it.
“Probably the harlequin ladybug has therefore its Achilles heel, we just have to find it”, says the experts.
Maybe being careful not to damage other species in the meanwhile.