The Assassin Bug is a great partner for your garden. They feed on garden pests and can be found in most world regions. These beneficial insects are nocturnal. They will come out at night to hunt for food.
They inject their prey with a dose of saliva through its syringe-like mouthpart. Saliva contains digestive juices that flow around the prey’s body, quickly turning it into a soup of nutrients. Venom in the saliva paralyzes victims’ muscles, so they can’t escape while consumed.
Identification of Assassin Bug
- The eggs are barrel-shaped.
- These eggs can be found in various colors, including orange, yellow and brown.
- Assassin bug nymphs are smaller than 1/2 inches (12.7 mm).
- They are usually bright orange, red, yellow, or green with dark markings. The first nymph’s body is typically translucent.
- They have enlarged, spindly legs.
- Nymphs have two large compound eyes.
- Assassin bugs have small, narrow, oval-shaped heads.
- They have 6 enlarged, spindly legs, especially the front ones, for capturing their prey.
- It has a long scythe-like mouth part for piercing its prey.
- These beneficial insects also have 2 large compound eyes and 2 long antennae.
- Their color is usually dark brown or black, but they also can have different color variations depending on the species.
- Most species are 1/2 inch (12.7 mm) long. Some can grow larger, up to 1 inch (25.4 mm) long.
- They have long, slender bodies and wings folded on their back.
Life cycle of the Assassin Bug
The life cycle of the assassin bug is complex. There are over 7000 species, each with its own life history and habitat preference. However, all species go through egg, nymphal, and adult stages.
Females lay many eggs in cracks and cavities throughout the fall. The following spring, the eggs will hatch. The tiny nymphs will feed on other insects and go through several molts before reaching adulthood.
Assassin bugs are hemimetabolous, meaning nymphs will gradually develop without metamorphosis to become adults. Larvae look much like adults, except they are smaller and wingless.
The life span of assassin bugs is about two years, and these insects can also overwinter as adults.
Pest Assassin Bugs Control
These beneficial insects eat many types of garden and woodland pests, such as:
- Cabbage Caterpillar
- Colorado Potato Beetles
- Cucumber Beetles
- Four Lined Bugs
- Japanese Beetles
- Lace Bugs
- Mexican Bean Beetles
- Stink Bugs
- Tobacco Budworms
- Tomato Hornworms
And many other caterpillars.
How to Attract Assassin Bugs
Food. Assassin bugs will be present as long as there is food. The more insects you have in your garden, the more attractive your garden becomes to these beneficial predators.
Reduce Pesticides. All beneficial insects are susceptible to chemical pesticides. Pesticides will also kill off many of the pests that assassin bugs depend upon for survival, which forces them to look for food and shelter elsewhere. Reducing or even eliminating pesticides will increase the pest population, keeping a beneficial insect population higher.
Habitat. The more variety of habitat there is, the more attractive your garden becomes to beneficial insects.
Interesting Facts About Assassin Bugs
- Assassin bugs are not aggressive toward humans or pets unless they defend themselves, their young, or are provoked. Their bites can be intense and painful, but they only last for a short time. They also can cause a nasty reaction resulting in a burning sensation and painful itching. To ensure you don’t get bitten, wear gloves when gardening in places where these bugs live.
- Some species’ colors act as camouflage. They blend in with grasses, leaves, and branches. Other species’ bright colors serve as a warning to predators.
- Some species of these crawling predators are ambush hunters, lying in wait for hours or even days until they can make a kill.
- Assassin bugs do not live in colonies, so usually, you will not see many of them in your garden.
- There are 7000 species of assassin bugs. Most of them are beneficial predators. However, 130 species in a subfamily called Triatominae, widely known as kissing bugs, conenose bugs, or vampire bugs, are not beneficial. Their food source is the blood of vertebrates (which includes the blood of humans). These bugs are potential vectors of several diseases. Therefore, some can carry Chagas disease. For non-experts, It’s hard to tell the difference between the beneficial assassin bug and the kissing bug. 
What to Do Next
Check out our other Beneficial Insects Guides. Read and learn more about how to identify their benefit and how to attract them.
Check out our Garden Pests Guides. Read and learn about how to identify and control garden pests.
Also, check out our Gardening Guides to learn easy step-by-step tutorials.
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