The impressive red palm weevil (Rhynchophorus ferrugineus) has spread to a large part of the Middle East and almost the whole Mediterranean area. Its large and terrifying larvae cause severe damage to certain palm tree species, such as Phoenix.
Adult palm weevils cause feeding damage to the leaves, but the most important damage is caused by the larvae. Larvae spend their whole life in the trunk. The first signs of infestation and damage are hardly perceptible and is only noticed in an advanced stage. The crown and trunk show boreholes with a brown viscous liquid and chewed fibers coming out. Inside rotting occurs and the leaves turn yellow and wilt. By the time damage is observed, the palm tree is already irreparably injured and dies. The trunks which are hollowed out by the larvae give insufficient support, as a result of which the palm trees can fall down.
Their reddish brown body of an adult weevil measures between 2 cm and 5 cm in length. The wing shields are dark red and have long vertical grooves. The reddish brown back shield is covered with some black spots. The head and remarkably long snout take up, together, 1/3 of the total length. At the base and sides of the snout the antennae and small black eyes are located. Two small mandibles are found at the end of the snout. Males have small brown hairs halfway along the snout. The eggs are creamy white and elongated. They are approximatively 3 mm long. Full-grown larvae are cone-shaped and cream-coloured. They are approximately 5 cm long. Their brown head has well-developed jaws, so that larvae can easily bore into the trunk of a palm tree. Before the larvae pupate, they make an oval-shaped cocoon out of palm fibers. These cocoons are on average 6 cm long. The pupae are pale brown and about 3.5 cm long. All stages of the palm weevil can be found inside the palm tree. Its total life cycle takes about 4 months. A female deposits more or less 300 eggs close to the base of the palm crown. After two to five days the larvae hatch and bore into the trunk where they feed on the soft and succulent palm tissue. The larval stage lasts one to three months. The pupal stage is shorter and takes two to three weeks, at the end a new adult emerges.