Tsetse flies are large biting flies that live in the tropical regions of Africa. They bite vertebrates, and drink their blood. They are the insect vectors of some serious diseases.

They have been studied a lot because they can spread sleeping sickness and other diseases.

The genus Glossina has about 34 species in three groups of species. One group of species lives out on the savannah; another group lives near rivers, and the third group lives in tropical forests.