Are ladybugs harmful?

Ladybugs are a very common insect in rural areas. They often prey on pests such as scabies and play a very important role in maintaining the balance between plants and pests. The ladybug is also called the seven-spotted ladybug, which is mainly named after its appearance. However, many people stay away from ladybugs, believing that they are bad for people. So, are ladybugs harmful?

Ladybug is a common name for beetles with round protrusions in the family Coccinellidae[1] of the order Coleoptera. They are small insects with brightly colored bodies, often with red, black or yellow spots. It is also known as Fatty, Matchmaker, Flower Sister (referring to the twenty-eight-spotted ladybug, which is a pest), Golden Beetle, and even because some species have smelly secretions, they are commonly called stinky beetles (but this is also a mixed name).

The adult ladybug is 1.0~16.0mm long, with a short oval to round body shape, a strongly arched dorsal surface and a usually flat ventral surface. Viewed from the dorsal plane, the pronotum and elytra are often closely connected and are usually of similar width. The head is often embedded in the pronotum and is sometimes completely covered by the pronotum. The back of the pronotum and elytra are smooth, or often have sparse or dense fine short hairs.

Most ladybugs have the following three characteristics: the tip of the mandibular palp is axe-shaped, the tarsus is hidden in four segments, and the first ventral plate has a posterior base line, which can distinguish them from other closely related species. The shorter legs and antennae (usually inconspicuous) and the lack of obvious notches on the back of the elytra also help to distinguish them from other closely related families.

But some ladybugs are long, more than twice as long as their width, such as the large-spotted long-legged ladybug (Coleomegilla maculata) from North America.

Predatory natural enemies associated with biological pest control. Most of the ladybugs are aphids. Important natural enemies of pests such as scale insects, whiteflies and mites play a vital role in maintaining the balance between pests and plants in natural and artificial ecosystems. Feeds on fungal spores (fungivorous ladybugs), especially powdery mildew.

Therefore, these ladybugs play a role in the prevention and control of powdery mildew. Collecting, raising and selling ladybugs is also an industry, and many natural enemy companies sell predatory ladybugs. In addition, ladybugs are often used as experimental materials in other life sciences such as evolutionary biology, population ecology, genetics, cytology, biogeography and species issues.