Maarten de Groot
Fig. 1. Larva of Apethymus abdominalis
Adults are small wasps (6.5-11 mm) with black thorax and yellow abdomen. Antenae are black and legs are yellow. Eggs are milky white and oval and are laid under the bark. Larvae have five stages. They have 3 + 8 pairs of legs. It can grow up to 20 mm. is green in the first stage. In the last stages it has waxy powder on the body. Prepupae is green and shiny. Feeds mainly in spring on leaves. Larval development is in spring. Diapause is over the summer and it swarms in October till November.
This species feed on the leaves of Quercus spp. Occurs in forests. Eggs are under the bark.
Occurs in all countries in the refocus area (Austria, Croatia, Hungary, Serbia and Slovenia). The density differentiates strongly between the countries.
The Common sawfly is attacking the leaves of oak trees. Can locally cause severe damage in oak forest.
Few sawfly species have a similar life cycle. Apethymus braccatus occurs also on oak. Adults are mainly black, while larvae are dark grey above and light grey at the sides and below.