Physiological Distinction between Aestivation and Hibernation in the Lady Beetle, Coccinella septempunctata bruckii(Coleoptera : Coccinellidae)

Abstract

The lady beetle, Coccinella septempunctata bruckii is basically bivoltine in Japan, in which the 1st-generation adults aestivate while the 2nd-ones hibernate. In the aestivating adults the respiration and oogenesis were inhibited completely and the topical application of juvenile hormone analogue (JHA) to them induced the termination of aestivation. Whereas in the hibernating adults the respiration rate remained at a relatively high level and transferring them to 25°C from the outdoor induced immediately the ovarian development, but JHA stimulated slightly the oogenesis and respiration. Observation indicates that the aestivation is the true diapause controlled by corpus allatum, whereas the hibernation is not. Voltinism type of C. septempunctata in Japan is quite different from that in Europe.