Larva - Up to 50 mm, They are whitish, and have three pairs of thoracic legs and false legs, as well as a single hook at the end of their body (characteristic that the difference of Parantrene tabaniformis).
Adult - 35-45 mm (wingspan) His appearance resembles that of a wasp, with the abdomen yellow and black, although it lacks the constriction at the beginning of the abdomen that these have. In addition, the wings are darker and have fringes and the antennae have hairs at their base.
The adults appear in the middle of spring, they mate and the female makes the laying on the same bark of the tree, in the first meters of trunk. After the revival of eggs (late spring), the neonatal larvae feed a short period of time on the outside trunk and branches (of the cambium), then penetrate the interior of the tree digging descending food galleries. At the beginning of the following spring they complete their development and pupan in the same gallery, previously they have practiced an exit hole to the outside that plugs with sawdust. Finally adults appear, thus closing the cycle.
Symptoms / Damage
The caterpillars practice galleries in trunks and branches, observing remains of sawdust with which the caterpillar plugs the orifice. In the trunk normally attacks are concentrated in the first meters of height. The galleries are descending, unlike parantrene that makes them ascending.
General weakening of the tree, lack of vigor and even the death of the specimen.
The branches can break easily, which is a serious problem in urban spaces.
Finally, these attacks favor the entry of fungi and bacteria.
Chemical control in drilling pests is complicated by the difficulty of pesticides and caterpillars coming into contact.
Moment: in spring and summer, during the hatching of eggs to act on the larvae before they enter the interior of the wood.
Indispensable to place baited traps with the specific pheromone, for the capture of males, which allows to carry out an adequate follow-up of the populations and to know when to treat.
By pruning the affected parts can be eliminated, preferably when the caterpillar is still inside.