Ladybugs: Natural History & Interesting Facts

Ladybug is the colloquial name for beetles in the family Coccinellidae. Ladybugs, also called ladybirds and lady beetles, are well known for their diminutive appearance, colorful shell patterns, and agricultural benefits. Most species of ladybugs play an important role as they prey on virulent pests such as aphids or scale insects. 

Ladybugs are ubiquitous around the world and there are over 6,000 documented species.

Source: Pixnio

Ladybug Description

Most ladybugs are colored a bright orange, red, or yellow with small black or brown spots on their wing covers. These markings can vary greatly depending on species, location, and even age. Some species have dots, others stripes, and others no consistent markings at all. A small minority of Coccinellid species are black, gray, or brown which can make it difficult for entomologists to identify them as Coccinellids.

Ladybugs have compact dome-shaped bodies and the majority of species are small, measuring between 0.03-0.7 inches long. Like all insects, they have 6 legs and a pair of antennae situated on the head. Their wings are stored under the elytra when not in use. Ladybugs are not considered to exhibit sexual dimorphism, though females do tend to be larger than males of the same species.

Source: Needpix

Ladybug Diet/Behavior

A significant portion of ladybugs are predators and feed on adults and larvae of other species. The most common insects eaten by ladybugs are aphids and scale insects, though the exact diet of predatory ladybugs can vary greatly depending on the species.

For instance, ladybugs in the genus Stethorus specialize in eating mites and many larger species specialize in eating caterpillars and beetle larvae. Several ladybug species are herbivorous and subsist mainly on foliage and plant material, including corn, beans, wheat, and more. Ladybugs have been known to engage in cannibalism when food supplies are scarce.

Major predators of ladybugs include birds, frogs, rodents, wasps, spiders, and dragonflies. Many ladybugs species developed their bright colors as a defense mechanism to deter predators from feeding.

When ladybugs mate, the female can store the male’s sperm for up to 3 months before fertilizing her eggs. Ladybug eggs are normally laid on or near plants that host prey sources. It is believed by some entomologists that ladybugs deliberately lay infertile eggs as an emergency source of food. The average lifespan of ladybugs is 1 to 2 years on average.

Sospita vigintipunctata, one of the rarest species of ladybug in Europe. Source: G. S. Martin via Flickr CC-BY-SA 2.0

Ladybug Interesting Facts

  • Ladybugs are technically not bugs but are beetles.
  • It is a common myth that the spots on a ladybug’s carapace determine its age. This is false. While markings can change as the insect ages, markings are determined by species and genetics.
  • Many ladybugs species are agriculturally beneficial but some herbivorous species are themselves major agricultural pests.
  • The word “lady” in the name “ladybug” is thought to refer to the Virgin Mary. This etymology is reflected in the German name for ladybugs Marienkafer, which literally translates to “Mary beetle.”
  • Some ladybugs exude an alkaloid toxin from their joins that discourages predators.
  • Ladybugs enter diapause during the winter and reemerge during the spring.