Flat Grain Beetle
Key Features
The Flat Grain Beetle (Cryptolestes ferrugineus) is a small beetle (2 .5mm) in length. It is reddish-brown in colouration, with
flattened body and very long antennae. Feeds on dried fruits, cereals, and other commodities.
Biology
Breeding conditions are temperatures between 17.5°C to 37.5°C, and relative humidity greater than 50%. Females lay their eggs
singly, either directly on the kernel or loosely in among food material.
The larva is whitish, almost translucent and flat. The head capsule and urogomphi are amber color. The larva is very active and
moves freely among the commodity in storage. The shortest development period is 22 days at 35°C, and 90% relative humidity.
The optimum temperature conditions for development are between 28°C-33°C.
The larva pupates among the commodity or in a hollowed-out cavity in a kernel.
Distribution
World-wide distribution with a preference for temperate climates. Cosmopolitan in choice of habitat, infesting all manner of
commodities in both commercial and domestic food stores.
Significance
The eggs are deposited on the grain. After hatching the larvae usually feed in the germ layer of the wheat kernel. This insect does
not cause obvious feeding damage to grain that the weevils and lesser grain borers do. This insect does not require broken
kernels or fine material to survive but will reproduce faster when it is present. It is the most common insect pest of farm-stored
wheat and frequently builds up to high numbers.
Control
Careful hygiene and monitoring are important in preventing and identifying this prevalent pest. Infested materials should be
disposed of, and hygiene improved. In severe infestations, fumigation of infested foodstuffs will control all stages of the life-cycle,
and arrest the infestation.
Monitoring strategies may be used to increase control efficiency.
