An invasive agricultural pest that damages a wide range of vegetable and horticultural crops has been detected in Tasmania for the first time, prompting a biosecurity alert.

Biosecurity Tasmania confirmed on Wednesday it is investigating the discovery of the serpentine leafminer at a commercial growing property in the state’s north-west. The pest, a tiny fly whose larvae tunnel through plant leaves, has been present on mainland Australia since 2020 but had not previously been found in the state.

According to a Biosecurity Tasmania spokesperson, the agency is working with the affected grower to manage the detection and has put “site-specific biosecurity directions” in place to control and minimise any spread. Investigations are also underway to trace potential movements of stock to understand how far the pest may have distributed.

The serpentine leafminer poses a significant threat to a broad variety of crops. The larvae create distinctive squiggly white lines, or “mines,” as they feed inside the leaves. This damage can reduce plant growth and crop yields, and in heavy infestations, can make leafy green vegetables unsaleable, as reported by Pulse Tasmania.

The pest is known to attack more than 200 plant species, including important Tasmanian crops like potatoes, beans, peas, brassicas (such as cabbage and broccoli), lettuce, celery, and tomatoes. It is classed as “prohibited matter” under Tasmania’s Biosecurity Act 2019.

Identifying the serpentine leafminer can be challenging for growers because similar, less harmful leafminer species are already common in Tasmania, according to reporting by Pulse Tasmania. Confirmation requires entomologists to either rear the larvae into adult flies or conduct molecular testing.

Biosecurity Tasmania is urging growers and the public to be vigilant and look for signs of heavy infestations or damage on plants not usually affected by common local leafminers. Anyone who suspects they have found the pest is advised not to move any plants or plant material from the site and to report it to Biosecurity Tasmania.

The original report on this detection was published by ABC News.