Assassin Bugs, Family Reduviidae

Habits and Traits of these Cunning Killer Insects

Assassin bug.
Getty Images/Moment Open/Valter Jacinto

Assassin bugs get their name from their predatory habits. Gardeners consider them beneficial insects, because their voracious appetites for other bugs keeps pests under control.

All About Assassin Bugs

Assassin bugs use piercing, sucking mouthparts to feed, and have long, slender antennae. A short, three-segmented beak distinguishes Reduviids from other true bugs, which generally have beaks with four segments.

Their heads are often tapered behind the eyes, so they look like they have a long neck.

Reduviids vary in size, from just a few millimeters in length to over three centimeters. Some assassin bugs seem rather bland in brown or black, while others sport elaborate markings and brighter colors. The front legs of assassin bugs are designed for catching prey.

When threatened, assassin bugs may inflict a painful bite, so be careful handling them.

Classification of Assassin Bugs

Kingdom – Animalia
Phylum – Arthropoda
Class – Insecta
Order – Hemiptera
Family – Reduviidae

The Assassin Bug Diet

Most assassin bugs prey on other small invertebrates. A few parasitic Reduviids, like the well-known kissing bugs, suck the blood of vertebrates, including humans.

The Assasin Bug Life Cycle

Assassin bugs, like other Hemipterans, undergo incomplete metamorphosis with three stages—egg, nymph, and adult. The female lays clusters of eggs on plants.

Wingless nymphs hatch from the eggs, and molt several times to reach adulthood in about two months. Assassin bugs living in colder climates usually overwinter as adults.

Special Adaptations and Defenses

Toxins in the assassin bug's saliva paralyze its prey. Many have sticky hairs on their front legs, which help them grasp other insects.

Some assassin bug nymphs camouflage themselves with debris, from dust bunnies to insect carcasses.

Assassin bugs do whatever it takes to catch a meal. Many employ specialized behaviors or modified body parts designed to fool their prey. One termite-hunting species in Costa Rica uses the dead termite carcasses as bait to attract live ones, then pounces on the unsuspecting insect and eats it. Certain assassin bugs in southeast Asia will stick their hairy front legs in tree resin, and use it to attract bees.

Range and Distribution of Assassin Bugs

A cosmopolitan family of insects, assassin bugs live throughout the world. They are particularly diverse in the tropics. Scientists describe about 6,600 distinct species, with over 100 types of assassin bugs living in North America.