Serpentine leafminer detected in Tasmania for the first time

The pest serpentine leafminer (SLM) has been detected at a commercial grower site in the north west, marking the first time it has been found in Tasmania.

SLM is a leafmining fly that is exotic to the state.

The larvae of this group of flies cause damage to plants by tunnelling through the leaves as they feed – these tunnels cause visible damage known as ‘mines’.

High levels of infestations can reduce plant growth and yields.

They are known pest to more than 200 plant species including potato, beans, peas, brassicas, lettuce, celery, tomato and cucurbits.

SLM can also affect ornamental plants such as chrysanthemums, gypsophila, ranunculus, and other nursery plants. Numerous weed species can act as reservoir hosts, allowing populations to persist between crop cycles.

The pest has been present on mainland Australia since 2020, and it is not yet known how it arrived in Tasmania.

A Biosecurity Tasmania (BT) spokesperson said SLM was a high-risk invasive pest of horticulture and vegetable production systems.

“BT is working with the impacted grower to manage the detection, with site-specific biosecurity directions in place to control and minimise spread.

“BT is also investigating potential movements, including trace back/forward of stock, to understand the potential distribution of the pest better.

“BT will work with affected Tasmanian industries to understand and determine actions to be taken following this detection.”

Growers and members of the public are advised they should look out for distinctive squiggly white lines on plant leaf surfaces caused by feeding damage from leafminer larvae.

“Good farm biosecurity helps to prevent the spread of pests, weeds and diseases.” Biosecurity Tasmania said.

“Remember to look out for new and/or unusual pests, weeds and diseases in crops, production areas and in high-risk inputs - e.g. mulch, fill, new planting material.

“Report them to Biosecurity Tasmania if you are concerned.”