Assassin Bugs

Assassin bugs may not sound very friendly, but they can do your garden a world of good as they suck the blood from many plant pests.

Assassin bugs are a family of insect predators. They also take blood from mammals, but we'll get to that in a moment. The two most common assassin bugs are the leafhopper assassin bug (Zelus renardii) and the spines assassin bug (Sinea diadema). These long-legged beneficial insects are originally from the tropics.

Leafhopper assassin bug (Goula Marta, et al) CC BY 3.0

Assassin bug description

​Assassin bugs tend to be slender and colorful, with round, beady eyes. One feature that makes them easy to recognize is their needle-like beak with 3 segments. They use that beak to inject venom into their prey, often after laying in wait for the right moment. [These bugs belong in a sci-fi detective novel!]

The nymphs are frequently confused with leaf-footed bug nymphs. Both are slender and they tend to be pale brown, blackish, or red. The nymphs are only 1/4 inch long, so you may never see them. Adults can each 3/4 inch. You are more likely to see clusters of the brown, white-capped, barrel-shaped eggs on leaves and stems. The adults are clumsy fliers, but they are voracious feeders.

Spines assassin bug (Julie Metz Wetlands) CC-BY-2.0

Assassin bug diet

Assassin bugs will eat pretty much anything they can sink their beak into. They seem to prefer caterpillars, leafhoppers, and aphids, but they will also feed on other beneficial insects, such as lacewings and honey bees.

Assassin bug or Kissing bug?

Close cousin to Kissing Bugs, assassin bugs have been known to bite people, though it is rare. Kissing bugs belong to a separate subfamily, Triatominae. Kissing bugs are nocturnal feeders, so you will rarely see them. They do, however, transmitting the microorganism that causes Chagas' disease. This usually only happens in rural Central and South America, but, as with chickens, you should keep these critters away from your face.

Kissing bug nymphs and adult (Etotalora) CC BY-SA 3.0

The next time you are walking around in your garden, take a closer look at what might be hiding as it waits for prey. It might be an assassin bug!