Season 149 - Day 8 of 14

These large biting flies that are obligate parasites feeding on the blood of vertebrate animals inhabit much of tropical Africa.
They include all three species in the genus Glossina and can easily be distinguished from other large flies by two features. They fold their wings completely when they are resting and the have a long proboscis that is attached by a distinct bulb to the bottom of their heads.
They have a prominent economic impact in sub-Saharan Africa as the biological vectors of trypanosomes, which cause human sleeping sickness – a disease that if not treated quickly can lead to the death of the infected human.
What is the name of these flies?