American Serpentine Leafminer detected

The Department of Industry, Tourism and Trade is increasing plant surveillance after a confirmed single sample of a leaf-mining fly in the Katherine region. 

The suspected Liriomyza trifolii was discovered after the Plant Biosecurity team increased surveillance for the plant pest following suspected samples were found in Western Australia and Queensland. 

There are many species of Liriomyza, including a native Australian species and other Australian flies which can appear to be similar in appearance. To confirm whether a sample is one of the 4 priority plant pests, the insects are subject to further testing. On Friday, 6 August 2021 the Plant Biosecurity team received morphological and molecular (DNA sequencing) confirmation that the single sample caught in Katherine is an American serpentine leafminer fly. 

In response, surveillance, trapping and community engagement about biosecurity threats will be increased across the Top End. 

American serpentine leafminer flies are a pest because they lay their eggs on plant leaves and the hatched larvae burrow into the leaf, destroying the inner tissue. This makes it harder for affected plants to photosynthesise. 

Affected plants may have wilted leaves or drop damaged leaves. Fewer leaves may also cause sunburn on fruit and reduced yield. Stressed and damaged plants are also more susceptible to bacterial and fungal diseases.

More information

For more information about the steps being taken by governments across northern Australia and information for growers and the public, head to the website: www.outbreak.gov.au/current-responses-to-outbreaks/american-serpentine-leafminer

Suspected cases of American serpentine leafminer should be reported to the department by calling the Exotic Plant Pest Hotline on 1800 084 881.