Asian ladybug - what it looks like, how dangerous it is and how to distinguish it from other ladybugs

All ladybugs are beetles from the ladybug family, which is also called “lady’s fudge”. Currently, about 4,000 different insects from this family have been described, including Asian ladybugs. In Poland, there are about 80 species of beetles from the ladybug family, such as the seven-pointed ladybug, the five-pointed ladybug and the colon ladybug. We all know these small insects very well, which do not harm humans and help to fight, including with very voracious aphids. Our local ladybugs are threatened by the Asian ladybug, which is already found all over Poland.

Ladybugs (Coccinellidae) are mostly useful beetles that are not burdensome and do not pose a threat to humans, although they live in close proximity to us, for example, in gardens and parks. One of the few exceptions is the Asian ladybug (Harmonia axyridis), which for some time “served” humans to fight aphids. It was introduced to the United States of America and Europe from Central and Southeast Asia. Unfortunately, his “farms” got out of control and the Asian ladybugs quickly spread, threatening other ladybug species. This invasive species is also potentially dangerous for humans - the bite of an Asian ladybug can lead to an allergic reaction, which is manifested not only by swelling and itching at the site of the bite, but also, for example, by swelling of the face and eyes.

1. Types of ladybugs found in Poland - characteristics

We all know the inventions of different types of ladybugs that are not hostile to humans. Our grandmothers often brought these insects home when the aphids that destroy them, which are the staple food of ladybugs, began to feed on houseplants. Ladybugs are very useful inhabitants of our gardens - in addition to aphids, they also eat beetles and some types of mites. Almost 80 species of beetles from the ladybug family live in Poland. The most famous:

• ladybug two-spot (Adalia bipunctata),

• five-spotted ladybug (Coccinella quinquepunctata),

• seven-spotted ladybug (Coccinella septempunctata).

Other species of this species include the Eurasian ladybug and the ten-spotted ladybug.

Many types of ladybugs are difficult to recognize at first sight. Ladybug beetles have a round, oval body that is red, yellow, orange, or black. You can easily recognize the colon, five- and seven-dot ladybugs by counting the black dots on the red shell of these insects - the number of dots indicates the specific type of insect.

Local ladybugs do not pose a threat to humans - on the contrary, they help control the population of aphids and other pests that destroy, for example, flowering plants.

Adults hibernate, including in the back streets of our houses and in the ground, under the bark of trees and, for example, in woodsheds. In spring, eggs are laid on the inside of the leaves, from which the larvae hatch. For predators, both adult ladybugs and their larvae are poisonous - nature has endowed ladybugs with protective mechanisms. Their color serves as a warning to other insects and birds - there is poisonous hemolymph in the body of ladybugs, but they do not pose a threat to humans. Thanks to this, both adult ladybugs and larvae should not be afraid of predators and can lead an open lifestyle. Most of our native ladybugs feed on aphids, red mites, and mites, however, for example, the yellow mealy ladybug feeds exclusively on powdery mildew.

2. Asian ladybugs (Harmonia axyridis) - characteristics

As already stated, Asian ladybugs are an invasive species that are depopulating our native seven dots, five dots and colons, which is not without harm to the environment. Due to the increase in the population of the Asian ladybug, incl. in Poland, other species of beetles from the ladybug family are beginning to be included in the group of endangered insects.

The Asian ladybug, also known as the harlequin ladybug or the ninja ladybug, is an induced species from Southeast Asia and Central Asia. Currently, its occurrence is very common in the United States of America and Europe. These insects are absent, among others, from Africa, Australia and South America.

The presence of the Asian ladybug in Poland was confirmed in 2006. Since then, the number of these beetles from the ladybug family has been systematically increasing. We can observe entire colonies of Asian ladybugs in the immediate environment, for example, in parks and at the windows of houses and apartments, in which they find a wonderful shelter for the winter. Asian ladybugs are also often seen in the spring when they leave their winter hiding places. In both our native ladybugs and Asian ladybugs, only adult insects hibernate and breed in the spring. In spring and autumn, the population of the Asian ladybug can increase up to 3 generations. The Asian ladybug is a predator - it feeds mainly on aphids, which makes it somewhat useful, but because of its aggressive nature, it threatens the biodiversity of ladybugs and humans. The Asian ladybug restricts food access to our native ladybug species and eats their eggs and larvae. Harlequin ladybugs reproduce at an alarming rate - one colony of these insects can number up to several thousand individuals.

Asian ladybug can have different colors. Most often it is yellow, orange or red with black dots, the number of which may vary. It also happens that the ninja ladybug is black with red dots. Its larvae also have a rather distinctive appearance - they have spikes and orange warts on their backs.

A characteristic of the Asian ladybug is the presence of white spots in the head area. Some individuals have a dark pattern in this place, forming the shape of the letter “M”.

3. How to distinguish the Asian ladybug from other ladybugs?

At first glance, it is very difficult to distinguish between different types of ladybugs, but we can recognize representatives of invasive species by several characteristics.

Basically, this is a large number of dots, white spots around the head, an M-shaped pattern on the head or forearm. Its body is more convex than, for example, that of a ladybug.

The Asian ladybug can bite a person, which means that its appearance in our environment causes problems. These insects are especially dangerous to babies and young children, but they can also bite our four-legged friends.

4. Why are Asian ladybugs dangerous?

Asian ladybugs are quite aggressive towards representatives of other insect species from the ladybug family. A threat to humans is posed not only by adults, but also by larvae, which often feed on leaves, for example, fruit trees and shrubs. Asian ladybugs can enter our homes and apartments through open windows in search of shelter, which means we can have very close contact with them, which increases the risk of being bitten.

5. Asian ladybug bite

The bite of an Asian ladybug is painful. A red bubble appears at the site of the bite, it itches quite strongly. Occasionally, a mild or worsening allergic reaction, including significant swelling, may occur. Fortunately, most bites do not lead to complications. However, it is worth remembering that an allergic reaction can be caused by both the bite of an adult insect and the larva, and it does not have to appear after the first bite. We must especially protect ourselves against these insects when we carry out, among other things, gardening work in the area where they live, such as pruning plants that show aphids.

6. How to get rid of Asian ladybugs in our environment?

There are several effective ways to get Asian ladybugs. One of the best is planting plants that repel these insects. Herbs are ideal for this purpose, including peppermint, which gives a very intense aroma. Asian ladybugs also do not like sour fruits, which means that we can use citrus essential oils, for example, to fight these insects.

If we find a colony of these insects behind a curtain or in a window frame, we must collect them with a vacuum cleaner and dispose of the contents of the dust container in such a way as to prevent the re-infestation of insects in our personal space. The bag from the vacuum cleaner should not be thrown into the household trash, as the insects will quickly leave it and start looking for shelter again. We can also install special insect houses in the garden, thanks to which ladybugs will not seek shelter inside the house.