Cold tolerance of the montane Sierra leaf beetle, Chrysomela aeneicollis

摘要: Small ectothermic animals living at high altitude in temperate latitudes are vulnerable to lethal cold throughout the year. Here we investigated tolerance of leaf beetle Chrysomela aeneicollis elevation California’s Sierra Nevada mountains. These insects spend over half their life cycle overwintering, and may therefore be winter cold, prior studies have demonstrated that survival is reduced by exposure summertime cold. We identify overwintering microhabitat this insect, describe strategies all stages, use microclimate data determine importance snow cover buffering for overwinter survival. Cold varies among history stages typically correlated with temperature: hardiness lowest chill-susceptible larvae, highest freeze-tolerant adults. Hemolymph osmolality higher quiescent (overwintering) than summer adults, primarily, but not exclusively, due elevated hemolymph glycerol. In nature, adult beetles primarily litter suffer mortality if early, unseasonable prevents them from entering refuge. suggest tightly linked stage. Thus, population persistence montane become problematic as climate becomes more unpredictable change uncouples phenology development timing extreme events.