Bug of the Week Vol.6- Ladybug

20 July 2024

Introducing the polka dotted princess, the ladybug. Scientifically known as “coccinellidae”, this family of beetles consists of over 6000 species and has a worldwide spread, an army if you will. In England, these critters are more commonly referred to as ladybirds, with “lady” representing Mother Mary, a prominent figure in Christianity. The specific species of coccinellidae I will focus on in this article are the most common species found in Europe, the “coccinella septempunctata”, which have seven black spots. These were associated with the seven joys of Mary, a representation of important events throughout her life.

Physical Description

The common ladybug has a small, round body consisting of elytra (a protective layer above their wings), which is opened before flying. The pronotum is black, with two eyes that have white spots above them. The elytra is bright red with 7 black spots, three on each half of the body and one in the upper middle area of the body. The bright red elytra serves as a form of defence, warning predators of potential harm and the bad taste of fluids that ladybugs release when threatened. This defence mechanism is known as aposematism, as seen in other species such as frogs with bright patterns to warn predators of toxicity and poison. The use of red in particular is effective as it heavily contrasts the green plants which ladybugs commonly reside in. Adult ladybugs can grow up to 7mm-12mm in length. Their design makes for a very simple drawing which my 4 year old self was grateful for, the closest feeling to being an artistic pro as it gets.

Life Cycle

This species of ladybug is carnivorous, feeding off very small insects as well as their larvae and tissue. They are not as sweet as I had imagined! Ladybugs have little activity during winter, with spring being the season for locating food and mating. They breed once to twice a year, with female ladybugs laying eggs which go through four stages before adulthood. These include the embryonic stage, the larval stage, the pupal stage and then finally being fully grown. Up to 30 eggs can be laid at a time on foliage beneficial for nutrients. Approximately one week later, larvae hatches from the eggs. After two more weeks, the larvae becomes fully grown and attaches itself to a surface to pupate. This process takes 7-15 days. The ladybug then grows into its final form, with a soft exterior that hardens over time.

Location

The coccinella septempunctata has a very wide distribution globally, having habitats in Europe, Ukraine, Russia, Korea, India and many more areas. This includes America, though they were introduced, making the USA fake fans of ladybugs. As these ladybugs feed on aphids (tiny sap sucking insects), they commonly reside in aphidophagous bushes and grasses within forests, fields and parks.

Environmental Impacts

These ladybugs bring both very beneficial and damaging impacts on environments, as they were actually introduced into North America as a biological control method in 1973, which was successful. Farmers are big fans of these guys, as they help protect crops from plant-eating insects. Although this is so, concern has risen due to the risk of these ladybugs out-populating the native bug species of Northern America. I don’t blame them though, it’s not their fault that they’re there!