INDIRECT MONITORING OF AGONISTIC ENCOUNTERS IN LARVAE OF LESTES VIRIDIS (ODONATA, LESTIDAE) USING EXUVIAE LAMELLAE STATUS

Differences in interference competition between larvae of the damselfl y Lestes viridis (Vander Linden) were examined using caudal lamellae s tatus of exuviae. Exuviae from a small temporary fishless pond near An twerp (Belgium) where L.viridis was the only odonate present were stud ied. No lamellae loss during emergence was seen. Therefore, the lamell ae status of the exuviae reflects the lamellae status of the final ins tar larvae. The deviations of the distribution of the number of missin g lamellae per individual from a binomial distribution suggested that lamellae are not always lost separately or that some animals are more prone to agonistic encounters. I found no difference in agonistic enco unters between sexes. In accordance with the hypothesis of Pierce et a l. (1985) interference competition was higher in the lestid species in habiting small, temporary fishless ponds than in the coenagrionid dams elfly Ischnura posita inhabiting large permanent fish containing water bodies that was studied by Robinson et al. (1991).