Damsel bugs, working for you!

Over the past week, we’ve had several queries about tiny, very slender, brownish bugs turning up in pulse crops like lentils in the state's South East. Photos confirm these insects are damsel bugs (family Nabidae) and the good news is that they're important beneficial predators.

Around 10 to15 mm long with narrow, pointed heads, damsel bugs use their long, piercing mouthparts (stylets) to attack a range of small, soft-bodied insects, including aphids, thrips, springtails, mites, insect eggs, and even small caterpillars. They'll be particularly valuable in pulse crops this year as they feed on the aphids already present and help regulate budworm larvae, which has been reported in high numbers.

Correct identification is important as many “true bugs” (order Hemiptera) share a similar slender body shape, but not all are beneficial. Damsel bugs can be distinguished by their enlarged, muscular looking first front leg segment, which they use to grab and hold their prey while feeding. Their long antennae, bulging eyes, and very narrow head make them efficient hunters, while their long legs allow them to cover ground quickly when searching for prey.

They are often collected in sweep net samples, but will try to run or fly away quickly when disturbed. If you come across them in the field, especially near aphid colonies, take a moment to watch, you may see them seize and feed on prey in real time.

Other beneficial “true bugs” can also be found in grain crops, including assassin bugs (often brightly coloured) and predatory shield bugs. If you spot these or other unusual insects, please take photos and share them with us they are valuable allies in keeping pest populations under control.