How Assassin Bugs Use Sticky Resin to Trap Their Prey

The ability to use tools is not widespread in the animal world. It has previously been associated with mammals and birds. However, we are learning that some insects are also adept at tool use. One group of insects, the assassin bugs, can be seen using tree resin to catch prey in this fascinating YouTube clip. Let’s take a closer look at exactly how they do it and the significance of this behavior.

What Are Assassin Bugs?

The term assassin bug is used to describe a group of insects with predatory and stealthy behavior. They are generally considered beneficial to humans because they prey on pests that damage our crops. They belong to the family Reduviidae, which includes many genera, and they live in a wide variety of habitats all over the world. You will often find them in grasslands and forests, but they also inhabit fields and gardens.

There are around 7,000 different species, which come in many shapes and sizes. However, most have a long, flat body, a pair of wings, and slender legs. As you can see in the clip, they are carnivorous and use their long mouthparts (proboscis) to pierce their prey and pump digestive enzymes into the victim. Then, the dissolved tissue is sucked up. Before they can do this, however, they need to catch the prey!

Using Tools to Catch Prey

The assassin bugs shown in this clip feed on termites, while other species feed on worms, aphids, flies, and beetles. The challenge with many of these prey animals is that they can escape even after the assassin bug has grasped them. Assassin bugs are often found covered in sticky resin, so frequently, in fact, that they are sometimes referred to as ‘resin bugs’ or ‘sticky bugs’. Research has shown that by coating themselves with resin, the bugs are more successful hunters. The prey is rarely completely immobilized, but it is delayed just long enough for the bug to insert its deadly mouthparts.

This is significant because it is an example of assassin bugs using resin as a tool. This behavior fits the scientific definition of tool use because the bugs manipulate an environmental item, taking it out of its usual context and using it to gain a selective advantage through improved hunting techniques. More recently, an assassin bug species from Thailand and China (Pahabengkakia piliceps) has been observed using this same technique, but with resin droplets collected from the entrance of a bee nest to capture stingless bees.