Ips duplicatus

Northern bark beetle

Description

Beetles are 3.3-4.4 mm in length, dark-brown, with four spines at each side of the elytral declivity. The second and third spines arise from a tumescence which forms an arcuate ridge between them. This is most distinct in the male where the third spine is the largest and is capitate. Overwinters in the adult stage, less commonly also as a pupa or larva. Flight takes place in May. The galleries are similar to those of the eight-toothed spruce bark beetle, with the maternal tunnels shorter and slightly narrower. There are normally 2 or 3 of them, slightly forking away on the two-gallery side. Galleries are usually found in standing trees, rather than logs, and in the upper part of trees where the bark is relatively thin and where I. typographus has colonized the lower section. Its presence doesn’t extend to higher altitudes (above 800 m). The species spreads from northern (where is more common) areas into the south during last 10 years.

Symptom

The galleries are similar to those of the eight-toothed spruce bark beetle, with the maternal tunnels shorter and slightly narrower. There are normally 2 or 3 of them, slightly forking away on the two-gallery side. Galleries are usually found in standing trees, rather than logs, and in the upper part of trees where the bark is relatively thin and where I. typographus has colonized the lower section.

Tree Species: Spruce

Part of a plant- attacked: Tree trunk

Pest significance: Very harmful

Pest Category: Insects

Invasive Species: Yes

Present in EU: Yes