Flies often get a bad reputation and are often described as dirty and disgusting. There are those associated with filth and decay like blowflies and houseflies. And there are those associated with disease like the mosquito and the blackfly. But most of the flies in the world are beautiful and many are beneficial and all are fascinating in their own way.
Flies are members of the insect order Diptera. Diptera means two wings and that is exactly what sets the flies apart from other insects. They have two wings and two small gyroscope like projections just behind those that look like tiny knobs on the sides of the fly that are called halteres. Their compact body shape and the halteres make some of the most advanced flies excellent fliers. Anyone who has had a showdown with a housefly knows just how good they can be.
There are three main sub-groups or sub-orders of flies.
The Nematocera, which includes the mosquitoes (Culicidae), the midges (Chironomidae), the blackflies (Simuliidae), and the craneflies (Tipulidae) to name just a few. The Nematocera are considered to be the most primitive of the three suborders evolutionarily. If you look closely at a mosquito and compare it to a housefly you can see the segments that make up the body are more visible on the mosquito than the housefly.
The Brachycera includes the horse and deerflies (Tabanidae), the robberflies (Asilidae), and the Dolichopodids (Dolichopodidae)to name a few. Members of this suborder are considered to more advanced than the Nematocera and often the common members are large and conspicuos. The flies of this group can often be determined by the three fleshy foot pads or empodia on the ends of the legs.
The Cyclorrhapha includes houseflies (Muscidae), blowflies (Calliphoridae), fleshflies (Sarcophagidae), shoreflies (Ephydridae), and hoverflies (Syrphidae) to name a few. These flies are considered to be the most advanced and are often the best fliers and manuveur very well through obstacles.