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Assassin bug

Assassin Bug

The untamed residents of North Florida

The growing season is underway with plenty of moisture recently and the acceptable temperature range. Home gardens are delivering quite the bounty for those who have made the effort to cultivate their favorite vegetables.

The untamed residents of north Florida are also benefiting from the favorable growing condition. High in this category are caterpillars which are currently finding plenty to eat, and this is critical for threatened species like Monarch butterflies larval state which consume only milkweed.

Typical of any garden, there are those species which view each foliage dense location as an open smorgasbord ready for their visit. Luckily, there are those who stand guard and prevent the total pillaging of these important resources.

Among the many native hunter insects is the milkweed assassin bug, Zelus longipes. Sometimes known as the long-legged assassin bug, it displays the bright coloration of a novice deer hunter especially when in juvenile stages of development.

Milkweed assassin bug

This species is common in southern North America, especially in the Gulf Coast and South Atlantic states. Additionally, variations on this species are found in Central America, the West Indies and much of South America.

This winged bug is slightly less than 3/4 inch long and has a slender, straight beak with piercing-sucking mouthparts. Their piercing and sucking mouthparts have three-segments.

When their beak is not in uses it is bent back and held under the thorax in a groove. It is carried much like a folding pocket knife, only to be extended when needed.

Adults and nymphs have a pear-shaped head, constricted neck and long hairy legs giving this insect an awkward, lanky appearance. Unlike many of the insects in the southeast, the shape and appearance is generally the same throughout its life.

Assassin Bug

This milkweed assassin bug has perfected its hunting skills. It is having a leisurely afternoon snack after a successful hunt

Unlike some of its domestic cousins which are rarely seen during the day and are hiding in leaf litter near their intended host, milkweed assassin bugs spend the days pursuing their prey. With their bright orange coloration, their presence is easily observed when contrasted with the green leaves.

The strategy used to catch its prey is known as the “sticky trap strategy.” Like many bugs which employ ambush tactics, the milkweed assassin bug attacks prey after hiding inside foliage with its forelegs raised in the air.

The exposed forelegs are covered with a viscous material which acts as a glue resulting in the prey’s entanglement. The target insect is rapidly paralyzed when the milkweed assassin bug inserts its beak into the host body.

Enzymes are released into its prey to dissolve its tissue, and the dissolved liquid is vacuumed out. This tiny predator can feed on prey that may be up to six times their own size.

Problems can arise when these insects encounter humans. It is capable of delivering a nasty surprise to the unsuspecting gardener working in plants who disturbs this ambush predator.

Not usually a life threatening injury, it is painful.  The bite is purely a defensive reaction to a perceived threat.

The good news is this assassin bug has little inclination to enter homes.  The green leaves and pretty flowers are an ideal habitat for the milkweed assassin bug’s hunting activities.

Remember, everyone is protecting their garden resources.

To learn more about the milkweed assassin bug, contact the local UF/IFAS County Extension Office. Click here for contact information.

One Comment on “Assassin Bug

  1. Thanks for posting information on the Milkweed Assassin Bug. Confirms my insect encounter while taking photos at the lake reserve near the beach at Abby Hanna Park in Jacksonville, Florida! Two of the critters were jousting atop a Spotted Water Hemlock bloom which made for an interesting photo topic. A variety of butterflies found among the abundant Water Hemlock plant blooms along the lake shore were the primary target to test a new camera body and and older telephoto lens. All in all a successful day for photographing insects of which I know little. A good article put to use by someone who has little knowledge of insect and plant life.