VARIATION IN THE OVERWINTERING ECOPHYSIOLOGICAL TRAITS IN THE COMMON GREEN LACEWING WEST-PALEARCTIC COMPLEX (NEUROPTERA, CHRYSOPIDAE)

The common green lacewing Chrysoperla carnea (Stephens) actually consi sts of a complex of sympatric forms whose taxonomic status is not yet clarified. In the study area (Loire valley), three of such forms are f ound: carnea Stephens, kolthoffi Navas and lucasina Lacroix, distingui shable on morphological basis.The study of temporal changes in overwin tering sites has revealed marked differences between the three forms. Carnea overwinters in rolled dry leaves and in ivy tufts, whereas kolt hoffi is preferentially found indoors. In spring, the two forms coexis t for some weeks in both dry leaves and ivy. At the end of spring, in bush and tree vegetation, only the kolthoffi is to be found in general . The more southerly lucasina form is only found in ivy in winter. The examination of ovarian condition of the numerically prevailing forms, carnea and kolthoffi, has shown a progressive recovery of reproductiv e activity along the studied period: the proportion of inseminated fem ales, very low in January, nearly reaches 100% at the end of April and the recovery of vittelogenesis starting in April, is ended by the fir st two weeks of May. A delay of two weeks is however observed between carnea and kolthoffi in the gradual recovery of reproductive activity. The brief coexistence in the same habitat and the observed delay of r eproductive activity apparently contribute to reduce gene flow between the three forms. Non typical specimens collected, at least in part co rresponding to the progeny of inter-form laboratory crosses, represent only less than 8% of the total sample, suggesting a low gene exchange . The overall differences observed, both morphological and ecophysiolo gical, are consistent with a specific status for these forms. As the t hree species may well show differences in trophic resources and behavi our has practical impact in the use of Ch. carnea sensu lato as effect or in biological control, research on their effectiveness appears much needed.