Public asked to help with beetle which targets avocado trees and is regarded as serious pest overseas

New Zealanders' beloved smashed avocado on toast could be in the firing line due to a pesky wood-boring beetle.

Biosecurity New Zealand is calling for the public to report any sightings or signs of the granulate ambrosia beetle.

Biosecurity surveillance and incursion manager Brendon Gould said they are assessing the potential risk the beetle could have on New Zealand.

"We need to know if New Zealand has a wider population, which is why we are asking the public to report any possible sightings," Gould said.

Native to East Asia, the beetle has been found in Africa, North America, Central America, some Pacific Islands and most recently in Queensland.

The unwanted beetle has been detected four times in Auckland since February 20, the first time it has been found in New Zealand.

The beetle is known to reside under bark which makes it difficult to detect but current evidence suggests it may have been in the country for the past two years.

It is known to feast on a wide range of broadleaf trees, including horticultural species such as avocado, and can spread fungal diseases.

Gould said the granulate ambrosia beetle leaves behind distinctive protrusions of compacted sawdust as they tunnel into trees.

The protrusions from bark look like toothpicks and other evidence of their being around includes sap oozing from tunnel entrances and branch dieback.

Officials are working with local Auckland authorities to identify the extent of the spread, including inspecting known host trees and placing traps nearby.

Anyone who believes they have seen the beetle or any sign of their being is asked to take a photo and call Biosecurity New Zealand's exotic pests and diseases hotline on 0800 80 99 66.