Latin: Tribolium destructor
The destructive flour beetle has only recently made its debut in Denmark, at least in comparison with other pests. Destructive flour beetle beetles were first found in Denmark in 1943, but they have since appeared more often. The Destructive flour beetle most likely came to Denmark from the tropics in Africa in connection with trade of goods between the two places. Anyhow it has also occurred in other countries that have traded with this part of the world.
In Danish, the Destructive flour beetle is named after a substance that it can secrete from its glands. This substance may have an odor like lysol, and this odor may stick to the goods which this species has been in contact with. Like the flour beetle, the Destructive flour beetle lives in dry goods such as flour and grains, and they can therefore be found in the home if you are unlucky.
Appearance
A Destructive flour beetle is 5-6 mm long and about 2 mm wide, it can be seen with the naked eye. It has a flat shape and has a dark brown color. The hind body is, as on most beetles, longer than the front body, and it has six legs and a pair of feeler horns on its head.
The larva of the Destructive flour beetle can be much larger than a fully grown beetle, in fact up to 10 mm long. The larva has a yellowish-brown color and can look like a very chubby worm to some people.
The Destructive flour beetle is often mistaken with the mealworm beetle, as they roughly have the same appearance. The mealworm beetle is however larger than the Destructive flour beetle, so if it looks like a smaller version of a mealworm beetle, it is most likely a Destructive flour beetle.
Likewise, the larva of the Destructive flour beetle can at times be mistaken with the larva of the mealworm beetle flour beetle, which is commonly called a mealworm. This is probably because the two species both belong to the same family, namely shadow beetles, also called Tenebrionidae.
Biology and behavior
Destructive flour beetle can become surprisingly old, in fact over three years. This also means that their full development takes time, compared to other pests. The time of the development time can vary, as it is a beetle, and it is dependent on the temperature.
The female destructive flour beetle can lay up to 1,000 eggs during her lifetime, and she often lays her eggs in flour or grains, although their eggs have also been found in bread, bird seeds, biscuits, and some types of pasta.
It takes a few weeks for the eggs to hatch, and the newly hatched larvae will immediately search for food (which is why the Destructive flour beetle lays its eggs directly in the food).
The larvae will thrive in temperatures around 28-30 degrees, where they can be fully grown in about a month, but in a normal kitchen the larva can grow, pupate, and become a Destructive flour beetle in just three months.
When fully grown, the beetles live in the same products, as they were born in, but since the fully grown Destructive flour beetle do not have to eat as much or often, one can find them far from the kitchen.
Damage
The greatest damage that Destructive flour beetle can cause is food related. Whatever foods the Destructive flour beetle lay their eggs in become infected. One can risk finding Destructive flour beetle in flour, grains, bread, biscuits, bird seeds, pasta, sugar, dried fruit, and even in spices. It is therefore important that you often check your foodstuff for beetles.
Prevention and control
Once you have Destructive flour beetle, it can be difficult to get rid of them, as the adult beetles do not need food that often, they can in fact be without food in up to two months. Therefore, one cannot starve them out of the house.
Try as far as possible to prevent them by keeping an eye on your foods stuff and by using airtight lids. In this way, the Destructive flour beetle, cannot destroy other foodstuff even if they have mange to get into your house. If you suspect destructive flour beetle in your foodstuff, you can freeze them. At zero degrees, the Destructive flour beetle, their larvae, and their pupae freeze to death in 12 weeks. This time span is shortened to just three days at minus six degrees. In the event of an invasion, chemical agents should be used, and if you live in an apartment, you should inform your neighbors.
"Pests in House and Home"
"Bed Bugs - Bites, Stings and Itches"
"Food Pests"
"Husets dyreliv" (Insects Around the House - Only danish)
"Skadedyr i træ" (Timber Pests - Only danish)
"Stuefluen" (Common Housefly - Only danish)