Your Garden's Deadliest Allies - UF/IFAS Extension Leon County

Your Garden’s Deadliest Allies

A bright orange milkweed assassin bug with long black legs rests on a sunlit green leaf, gripping a small dark insect it has captured beneath its body. — A milkweed assassin bug (Zelus longipes) puts its curved beak to work on a freshly caught insect. Bright orange with long, spindly black legs, this common Florida predator is exactly the kind of garden ally worth welcoming. Photo by Molly Jameson.

Your Garden’s Deadliest Allies

As a gardener, summer can feel like it takes knightly status to grow fruits and vegetables. You strap on your metaphorical armor, raise your shield, and draw your sword to battle the stink bugs, squash vine borers, armyworms, green peach aphids, and more.

The wheel bug (Arilus cristatus) earns its name from the cog-like crest arching across its back – a feature no other insect in North America shares, which makes it one of the easiest beneficial bugs to identify. It’s a voracious predator of caterpillars, beetles, and other soft-bodied garden pests. Photo by Jim Baker, North Carolina State University, Bugwood.org.

In the thick of it, it can feel like nothing in nature is on your side. But take heart – a few fellow warriors are out there fighting alongside you. One of the fiercest is the assassin bug.

These insects are voracious predators, armed with a powerful, curved beak called a proboscis that pierces unsuspecting prey. Once it strikes, the assassin bug injects a toxin that paralyzes its victim and liquefies the muscle and tissue inside. It then sucks out the liquefied remains, killing the prey.

Better still, assassin bugs feed on many of the very pests you’ve been battling – aphids, stink bugs, and caterpillars – along with flies, beetles, and even mosquitoes.

As helpful as they are in the garden, give them their space – that strike packs a punch! A “bite” from an assassin bug is painful but doesn’t generally require medical attention. Do seek care, though, if it triggers an allergic reaction such as swelling, itching, hives, or difficulty breathing.

Of the more than 7,000 known assassin bug species worldwide, only about 150 to 200 live in North America – but many of those call Florida home. Two you’re likely to meet in your garden are the wheel bug (Arilus cristatus) and the milkweed assassin bug (Zelus longipes). Give them room but know they’re on your side.

Learn more about assassin bugs, including the wheel bug and milkweed assassin bug, through the UF/IFAS Featured Creatures collection website: