Drone Fly Eristalis tenax
The Drone Flies can be seen in everybody's garden in summer. Larvae of the Drone Fly are very remarkable. They live in stale and very polluted water with almost no oxygen. As a solution to this problem they developed a very long tube on the backside of the body. This tube is put out of the water like a kind of a periscope and is used to breath through. This tube is probably the reason why in Dutch they are called Rat's Tail Larvae. The Drone Fly does look like a common Honey Bee indeed. It is more robust, shiny and a little darker though. The two animals are also easily told apart by the eyes: Drone Flies have very large eyes, typical of flies.
Drone Flies make up the infamous genus of Eristalis. Infamous for this genus is comprised of some 15 species. These species are real look-a-likes and very hard to tell apart. The females are even harder to identify for not only are they extremely variable, they often also lack the orange spots commonly found in males. Two very common species are especially troublesome: Eristalis tenax, the real Drone Fly and Eristalis pertinax. The difference between the two species is the last part of the leg, just above the foot: in Eristalis tenax it is always black and in Eristalis pertinax it is always yellow. Also Eristalis tenax has two dark lines in the eyes. These actually are streaks of hair. They are obvious in both the top and bottom picture. When in the field you do need the right light to be able to see them, though.
