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Mealworms Life Cycle

A Look at the Mealworm Life Cycle

The mealworm life cycle can be a complex set of changes for such a small creature. The mealworm is often used as live food for several species of reptiles and even fish. If given the chance to grow to maturity, the mealworm will actually become a darkling beetle. This is a family of beetles that can be found all over the world, making the mealworm a very popular prospective insect!

Egg Stage

The first stage of the mealworm life cycle is the egg stage. This is the beginning of the mealworm’s life as well as the first in a series of complex stages. The egg is too small for the human eye to see, but under a microscope one will find that it is oval-shaped and white in color.  One female darkling beetle will lay hundreds of eggs in one go and each one will take anywhere from four to nineteen days to hatch.

Larva Stage

The second stage of the mealworm life cycle is the larva stage. The creature that emerges from the egg is what we consider to be a mealworm. This worm is typically an orange-ish color and its primary goal is to eat as much as possible! Sounds like a dream, to most of us! The mealworm’s diet consists entirely of vegetables or grain. In fact, many fisherman and people who have reptiles as pets will keep mealworms in a pot of oats, whole grain, or bran flakes. They will also nibble on bits of potato and carrots. This enables the mealworms to continue to grow and remain healthy until they are used as bait or food. They make an ideal food at this stage because they are filled with tons of protein. If the mealworms are being kept a source of food, it is imperative that they are kept in a container with a large surface area with steep, smooth sides so that they can move around without wiggling right out of the container. The larva stage lasts anywhere from four days to two weeks and during this time the mealworm will molt a number of times as it grows.

Pupa Stage

If the mealworm is allowed to mature further, it will go through the pupa stage. This is often described as being similar to the time in a butterfly’s life that is spent in a cocoon. During this stage, the mealworm is in mid-transformation from a worm-like creature into a beetle. The insect looks quite unique and almost alien in nature, as it has a tail while the head and midsection are transforming. The pupa is very inactive during this time as its body is going through a tremendous change. This stage can last anywhere from one to three weeks depending on the environment and how well the mealworm fed during the larva stage.

Adult Stage

This is the final stage in the life of what once started to be a mealworm. The end result is a darkling beetle. The beginning of adulthood results in a light brown color, although this soon changes to a deep black as the adult matures further. These beetles are equipped with wings, but oddly enough they are not capable of flight. The beetle will live out its adult life over three or four months where its purpose will then be to mate and proliferate the darkling beetle species. In fact, the average darkling female will lay around 500 eggs during her adult lifetime! At this time in their life, the beetle is most active and is most able to defend itself by biting or running from predators.