Control of Diapause by an ‘Internal Clock’ in Anthrenus verbasci (L.) (Col., Dermestidae)

Abstract

THE life-history of this carpet beetle under outdoor conditions in southern England is as follows. Adults emerge in June and July and may be found on many species of creamy-white flowers, notably cultivated Spiraea spp. and Heracleum sphondylium L. (hogweed). One of the main oviposition sites is dry birds' nest material found in the attics of buildings. Eggs hatch in about five weeks, but larvæ may require two years for complete development. Pupation occurs in early May, and lasts about a month; after a further week of inactivity the active adults emerge. When mating occurs immediately, eggs are laid from about one week onwards for at least a month. Adults die about the end of July. Experiments on the development of larvæ under outdoor conditions showed a clear annual rhythm of activity, namely, a rapid rate of moulting during the summer (May–August) and rest during the winter.