Ambush Bugs – Masters of Camouflage

Ambush Bugs – Masters of Camouflage
Bugs Main | Bugs Index | Assassin Bugs | Plant Bugs | Ambush Bugs

Order Hemiptera / Family Phymatidae Laporte, 1832. From the stegosaurus-like plates to the little horns on their head to the ocelli on bumps to the Venus-flytrap-raptorial forelegs, what's not to like?

This ambush bug has captured a cabbage white butterfly (Pieris rapae) and is in the process of sucking out its body fluids by means of its rostellum, or beak. Other types of bugs use this organ for sucking plant juices, but not the ambush bug. These stealthy critters sit very still on or near flowers, their superb camouflage allowing them to remain undetected while an unwitting butterfly or other unfortunate happens by to gather nectar. They then seize their prey using front legs adapted for the task – these legs resemble the front legs of the praying mantis. It is a ferocious bug indeed that takes prey 10 times its own size.

Ambush Bug spreads its wings
It's rare to see an ambush bug spreading its wings

Like all true bugs, ambush bugs undergo simple metamorphosis, from egg through nymph and adult stages. Clusters of eggs are laid by overwintered females when the weather warms in springtime.  After hatching, nymphs undergo from 4-7 molts, shedding their exoskeleton as they grow, eventually reaching the adult stage.

Ambush bugs are often lumped in with another family, the Reduviidae, which are commonly called Assassin Bugs. Both Phymatidae and Reduviidae are distinguished from other families by their short, 3-segmented rostrum (rostellum), or beak. The beak is used variously to pierce, inject poison into, and suck juices out of prey. Bugs in other families have 4-segmented rostrums more often adapted to simply sucking fluids from plant tissue. [2]

Ambush bugs can fly, but do so poorly, and generally only between adjacent flowering plants. I've never seen one do it.

There is anecdotal evidence some bugs in these two families can inflict painful bites on humans; in particular, the wheel bug, so-called for the peculiar structure on its thorax resembling an involute gear or radial saw blade.

Ambush Bugs Mating
Raptorial (adapted for grabbing and holding prey) forelegs are visible on this mating threesome. 


  1. Kenn Kaufman and Eric R. Eaton, Kaufman Field Guide to Insects of North America, 1st ed.
  2. Thomas Eisner, Maria Eisner, and Melody Siegler, Secret Weapons: Defenses of Insects, Spiders, Scorpions, and Other Many-Legged Creatures (Belknap Press, 2005).
  3. Les Line, The Audubon Society Book of Insects (Harry N Abrams, 1983).

Order Hemiptera: True Bugs number almost 5,000 species in North America, and 40,000 worldwide. They have mouthparts formed into a beak, adapted for sucking plant juices or the liquefied insides of their animal prey.
Suborder Auchenorrhyncha – Cicadas & Planthoppers
Suborder Sternorrhyncha – Aphids, scales, mealybugs, jumping plant lice