Cosairs Assassin Bug
Rasahus biguttatus

Nearly 3000 species of assassin bugs exist and scientists feel that many more will be discovered. These insects can be commonly found throughout most of the world. They vary in size from a few millimeters to as much as 1-1/4 inchs. They come in many colors and shapes and most species have two pairs of wings. However, all assassin bugs have a powerful, curved beak that is used to pierce and suck out the tissues of their prey.

Assassin bugs feed by pushing their beak into a victim's body and injecting a toxic fluid that liquifies the muscles and tissues of the prey. Most other insects that eat like this have two tubes in their beak; one for injecting the fluid and one for sucking in their food. Assassin bugs have only one large tube that does both jobs. This larger tube allows them to inject the toxic digestive fluid so that prey many times their size can be quickly overcome. Once the insides of the prey are turned into liquid, the assassin bug uses its tube to suck out the liquified tissues in much the same way we use a straw to drink.

Assassin bugs get their name because of the speed that they have to grab and poison their prey. They are carnivorous, or meat eaters, and use their powerful, jack-knife forelegs to grab their prey. They have sticky pads on these front legs, made up of thousands of tiny hairs, that stick to their victims and keep them from getting away. Some assassin bugs actively hunt their prey, while others patiently wait until their prey comes close enough to grab.

The saliva of the assassin bug starts to work almost immediately. Cockroaches have been seen to die in only 3 or 4 seconds, and caterpillars more than 400 times their weight can die in only 10 seconds! A feast this size can last for days or even weeks.

Most assasin bugs lay their eggs in the autumn in cracks and crevices that contain lots of leaves. The eggs hatch the following spring and the nymphs look very much like the adults, except thry are smaller. Assassin bugs go through incomplete metamorphosis (egg-nymph-adult). After hatching from the egg, the nymph passes through five growth stages, molting at the end of each stage, becoming an adult after the final molt. Adults often are the stage that live through the winter, and they begin a new generation in the spring. This insect preys on other insects and benefits people because they help reduce populations of certain pest species. But assassin bugs themself are preyed on by birds and reptiles. Some species have developed a unique defense where they use their beak to squirt their venom at their attacker as far as a foot away! Their saliva can cause severe irritation of the eyes and nose and even temporary blindness in humans!

Assassin bugs probably have the most painful bites caused by insects. Some South American species of assassin bugs also transmit a parasite to man that causes Chagas disease.


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