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RUST RED FLOUR BEETLE, Tribolium canstaneum


The red and confused flour beetles are nearly identical in biology and habits except that the red flour beetle flies and the confused flour beetle does not. The threat of the red flour beetle invading from an outside food source, such as grain spillage, must therefore be considered.

Red and confused flour beetles are capable of breeding year-round in heated buildings. The red flour beetle is found more often in southern, warmer states and the confused flour beetle is seen in northern areas. Either species, however, could be encountered anywhere. These flour beetles are also known as "bran bugs," being very significant pests of flour and flour by-products.

Female beetles deposit eggs in twos or threes within the food material until eventually 300 to 400 eggs are laid. The larvae hatch from these eggs in about nine days and go through from 5 to 18 molts. The life cycle from egg to adult may take 7 weeks to 3 months depending on temperature and humidity conditions as well as quality of the food source. The adult beetles may live up to three years or longer.

Flour beetles are scavengers in that they cannot attack whole grains and must rely on other insects such as rice weevils or lesser grain borers to damage the kernels first. These beetles are most common in processed grain products and their flattened bodies permit them to work their way into almost any package.

Flour and other processed food products heavily infested by these beetles often develop a greyish tint. This greying also promotes the growth of mold, which further contaminates the food product. Additionally, secretions from the beetles may add a disagreeable odour to the food product.

Advice for Rust Red Flour Beetle:

Use Fortefog Mini Fumers, Protector C or Agrodust.