A Mediterranean population of Pyrrhocoris apterus (Heteroptera: Pyrrhocoridae) exhibits wing morph-related differences in adipokinetic response

Short-winged (brachypterous) and long-winged (macropterous) adult females of Pyrrhocoris apterus (L.) originating from a Mediterranean population (Israel) were analyzed for their adipokinetic responses. The adipokinetic response, expressed as an increase of haemolymph lipids after injection of adipokinetic hormone from Locusta migratoria (Lom-AKH-I), was assessed in relation to age and dose of the hormone. We demonstrate in this study that the adipokinetic responses induced by bug's corpora cardiaca extract and Lom-AKH-I were dose-dependent for both brachypterous and macropterous females. Significant differences between the morphs were recorded for doses >= 0.25 corpora cardiaca equivalent (P = 0.25 pmol Lom-AKH-I (P = 5 days old) than in the brachypterous females of the same age, when treated with 2 pmols Lom-AKH-I. Starting from day 7, the concentration of haemolymph lipids was also considerably higher (2.5-5 times) in macropterous females than in the brachypterous ones. The obtained data indicate that difference in mobilization of lipids between brachypterous and macropterous females is a geographically independent feature and represents a true wing morph characteristic of P. apterus.