Spatio-temporal analysis of trap catches of Tribolium confusum du Val in a semolina-mill, with a comparison of female and male distributions

By using food-bait traps, we evaluated the presence and the spatio-temporal distribution of insect pests in an industrial semolina-mill, with particular attention to Tribolium confusum du Val in which the spatio-temporal dynamics of females and males were also studied separately. A total of 1401 insect specimens was captured in the traps, belonging to 14 taxa, mainly Coleoptera. The most abundant species were T. confusum (with 1002 adults), followed by Typhaea stercorea (L.) (with 158 adults) and T. castaneum (Herbst) (with 110 adults). Of particular interest was the presence in the food-bait traps of T. confusum and T. castaneum adults in a mixed population with equal numbers of males and females. Furthermore, analysis of the spatio-temporal dynamics suggested that the distribution of the two sexes in T. confusum was almost the same during the entire sampling period. The findings of our study can usefully be applied to the management of Tribolium infestations, but further and more detailed studies are needed to better understand the ecology and behaviour of the species in association with searching for food and production of aggregation pheromones.