- Scientific name: Tenebrio molitor
- Size: About 1 inch
- Color: Starts out white and ends up brown
- Shape: Long and tubular
- Found in: All over the United States
What are they?
Mealworms are the larval stage of the mealworm beetle. These mealworms are only larva for 3 to 30 to 115 days, depending on many different factors, including temperature and food sources. These mealworms are well known sources of food for many different types of animals, including those kept as pets such as lizards, birds and some species of snakes. Humans also consume mealworms in some areas of the world and they are beginning to gain a small foothold in the exotic snack market. They are valued for their high protein content and use as fishing bait.
How can you tell you have them?
Unfortunately for the same reasons that mealworms are so easy to use as a ready supply of easy food for pets, means that they are also quick to infest certain types of dried goods in a pantry. It is important to check your dried goods periodically, if you see white or light brown larva in your oatmeal, cereal or flour, or black beetles in or near your pantry, it may be a sign that you have mealworms. The adult beetles are most commonly seen in the summer, but in a warm home environment, they can breed and grow year-round.
What kind of environment do they like?
Mealworm beetles and their larvae prefer dark, damp places with a ready food supply, such as fallen logs, abandoned animal nests and farm silos. In the wild, mealworm beetles prefer to find dark, damp areas that are sheltered from predators. Because the the mealworm larvae are considered such a highly desirable food source for so many different species, it is rare to see a large gathering of larvae in the wild. Human breeding and development of the mealworm beetle produces the largest populations of mealworms. The mealworm beetle can access a human dwelling through open windows, gaps in the seal around doors and other small openings that are common in a home, especially older homes.
The mealworm larva feeds on both vegetative matter and dead animals. As their main source of food in the wild is food of opportunity, mealworms are perfectly suited to adaption to a human supplied food source, though they are pervasive pests in the home. It is important to remember that the mealworm has more than one form and getting rid of the larvae may not stop the infestation. Because the adult form of the mealworm is a beetle, they are far more mobile than their relatively helpless larval form.
What to do?
Make sure to periodically check and throw away old stores of food, especially dried goods. Keep your pantry clean, well lit and be sure to store foods in clean, airtight containers. Because mealworms feed and breed in areas where food is kept and prepared, it is important to be very careful when eradicating these pests from the home. Depending on the level of infestation, it might be wise to seek professional assistance in choosing what means are necessary.