Asian longhorn beetle
This large wood-eating beetle could seriously damage many trees important to New Zealand. Its long antennae are its defining feature.
About Asian longhorn beetle
This longhorn beetle is native to China and South-East Asia. Adult beetles can only fly a short distance. They usually stay on the same tree they emerged from.
Global distribution of Asian longhorn beetle
Why this is a problem for New Zealand
This beetle attacks many types of tree, including poplar, willow, pear, apple, and stone fruit.
The larvae eat the woody parts of the tree, while the adults eat the leaves and young bark. Larvae cause most of the damage. They can weaken and even kill a tree. Because they stay close to a single tree, they can cause a lot of damage to it.
The beetle and its larvae make wounds in the tree. These wounds can lead to infection with fungal and other diseases. The female beetle lays her eggs under the bark.
How could it get here?
The Asian longhorn beetle may sneak into New Zealand as eggs, nymphs, or larvae in wood, wood products, or wood packaging.
How to identify the Asian longhorn beetle
Key identifiers for the adult beetles:
- the antennae are twice as long the body of the beetle
- the body grows to 25mm to 35mm long
- they are black with 20 irregular white spots on their wings
- the antennae have a whitish-blue base.
You'll find this beetle on the leaves and young bark of trees like:
- fruit trees, like pears, apples, and stone fruit.
Right: The larvae can grow to 50mm long.
You may see holes in a trunk or a branch of a tree where larvae have chewed their way out.
Check for insect holes in any solid wood packaging or wood products you receive from overseas.
If you think you've found the Asian longhorn beetle
- photograph it
- catch it (if you can)
- call 0800 80 99 66
Note: This information is a summary of this pest's global distribution and potential impacts on New Zealand.