Latin: Tribolium confusum
The confused flour beetle is most likely one of the oldest pests that one may encounter. One of the oldest examples of the species, were found in a flour jug that a pharaoh had been buried with 2,500 years before our era.
Unfortunately for us, flour beetles still create destruction in modern times. Flour beetles are mainly a pest associated with foods in which they live and eat. They are found in flour and grains.
The confused flour beetle has not always been a problem in Denmark. Like so many other species, the flour beetle came to Denmark through trade. In Denmark, flour beetles cannot survive in the wild, so even if you can find them in flour, grain or grains, there is no risk that you take them home with you from the nature.
Appearance
As like most other beetles, the flour beetle larva is larger than a fully grown flour beetle. A flour beetle is just 2.5-4 mm long. It has a reddish-brown color and a very long hind body. Like most other beetles, it has six legs and, of course, antennas on its head. If you are not sure of the species, it can be recognized by its lively behavior.
Since the flour beetle is an insect, it has a larval stage. The flour beetle larvae are somewhat larger than an adult flour beetle, it can be 6 mm long. It is not only the size that differs. A larva of a flour beetle has a yellowish brown or beige color. Both front and hind are slightly darker. A flour beetle larva can also be taken as a worm with its chubby shape.
Biology and behavior
The confused flour beetle belongs to the family Tenebrionidae. The average female beetle lays between 300 and 500 eggs, but they can lay up to 900. This can lead to up to five generations per. year, depending on how fortunate the temperature is. The optimal temperature for flour beetle reproduction is about 30 degrees, but they can multiply at lower temperatures, as low as 18 degrees. Below 18 degrees there is no reproduction, and the flour beetles will therefore slowly die.
The development from egg to adult varies in time with temperature, humidity, and available nutrition. In wheat flour, with a humidity of 75%, the development at 32, 27 and 22 degrees, will take 27, 37 and 93 days. Adult beetles can live for up to three years.
The confused flour beetles are really good at getting into places where you do not want them. They can easily enter tight-fitting wrappers. Therefore, they can be a particular problem in places where you store your groceries.
Damage
The flour beetle can be harmful to both private homes and in industrial sectors. In the industry, they often attack feed and grain stocks. They can also be found among grocery stores. When found in the home, they have usually entered from the warehouses, and they can wander from one item to another. They can live in grains and flour. They can also survive on dried fruit, beans, chocolate, and spices. As they are not a picky animal.
The way to recognize the damage of flour beetles to one’s foods is when the infested foods get an unpleasant odor and taste. They also get a grayish color. It is not recommended to eat contaminated foods.
Prevention and pest control
Depending on whether the attack has taken place in private homes or in the industry, there are different approaches to the prevention and control of flour beetles. In the industry, flour beetles and other pests can be prevented by keeping a low temperature, preferably below 18 degrees, so that the flour beetles cannot multiply.
In private homes, it is more difficult preventing the flour beetles, as the temperature cannot be controlled as in a warehouse. Here the focus should be pest control. Flour beetles are controlled by discarding the infested goods. One can heat or cold treat infected good, if the damage is not to great. You can heat the goods for 60 minutes at 55 degrees or more. Alternatively, you can freeze the goods down to -18 degrees for 24 hours. Both treatments will kill beetles, larvae, and eggs. In the case of a severe outbreak, insecticides can be used.