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Sitophilus oryzae (L.)
(Calandra oryzae L.)
Rice Weevil


The appearance of this weevil is similar to that of the granary weevil; it is however smaller (2.3-3.5 mm long), and differs from the granary weevil in that it has four reddish spots on the brown wing covers.

Life History:

Develops within the kernel of grain, like the granary weevil; requires greater warmth than the granary weevil as it first develops at temperatures of above 55° F. Only few weevils survive the winter temperatures of the temperate zones; in tropical climates, the development of a brood may take only 1 month. The weevil can fly; in hot contries, the rice weevil flies to the fields and lays its eggs on cereal crops.


World-wide, through cereal trading. Of great importance in tropical and subtropical countries.


A dangerous stored grain pest in warmer countries; it infests all types of grain. The larvae can also develop in farinaceous products, buckwheat, peas, acorns, chestnuts and cottonseed; the weevil also feeds on flour, hemp-seed, biscuits, waffles, white bread and tobacco; often found together with granary weevils.

The maize weevil (Sitophilus zeamais Motsch.) is very similar to the rice weevil, but larger (3.3-5 mm), and the reddish markings on the wing covers are more clearly defined. Otherwise, as for rice weevil.

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