Cannibalistic behaviour of the first and second instar larvae of Plodia interpunctella (Hübner), Cadra cautella (Walker), Ephestia kuehniella Zeller, Corcyra cephalonica (Stainton) (Lepidoptera Pyralidae) under starvation

Abstract

Tests were carried out at three different environmental conditions: 18°C and 65% RH; 24°C and 63% RH; 28°C and 70% RH. Results can be summarised in the following: cannibalism was confirmed for P. interpunctella, C. cautella, E. kuehniella, C. cephalonica; it is more frequent at 28°C than 24 °C and l8°C; the probability of cannibalism depends on larval instar; cannibalism is more frequent in presence of different larval stages; the choice of the victim is made towards more vulnerable individuals, that are less resistant to the attack (no first instar larva was able to cannibalise a second instar one); at 28°C the survival time of cannibal first and second instar larvae is, with some exceptions, greater than those of starved larvae of the same stage.