Facts about robber flies
The most commonly seen robber flies are dark in color, but some common types are
orange. Several species even mimic bumble bees, with black and yellow stripes.
http://www.geller-grimm.de/genera16.htm
Larval and adult robber flies are predators of other insects, and are famous for
their ability to capture prey in the air. In fact, robber flies will often catch
insects that are larger than themselves, such as bumble bees.
Robber flies will occasionally bite humans, but they are not blood feeders, and
will only bite on accident or if provoked.
Kokopelli, an important figure from Native American folklore, is partly named
after "pelli," a word for the desert robber fly.
Over 400 genera [now 530] and subgenera have been proposed and about 4,761
species are known [now 7,003].
The robber fly has a beak enclosing a dagger-like shaft used to stab its victim
in the head or thorax and inject a fluid which kills it. This fluid soon causes
the victim's "insides" to become liquid and the robber fly then proceeds to suck
it dry, leaving nothing but an empty shell. They obviously need counselling.
(someone said they should be called the IRS fly)