Common cockchafer
for the larvae to fully develop. The grubs are 10 to 20 mm in the first autumn, 30 to 35 mm by the following autumn, and 40 to 46 mm in the spring of their [...] genus Melolontha, in the family Scarabaeidae. Damage symptoms The common cockchafer ( Melolontha melolontha ) does most of its damage in the larval stage [...] larval instars, a pupal instar and the adult beetle. The adult beetle is 25 to 30 mm long, with a dark head, black pronotum covered with short hairs, and