Blue bottle

Description:

It is 10–14 millimetres (0.4–0.6 in) long, slightly larger than a housefly. The head and thorax are dull gray and the abdomen is bright metallic blue with black markings. Its body and legs are covered with black bristle-like hair. It has short, clubbed antennae and 4 tarsi per leg. The eyes are red and the wings are transparent. The legs and antennae are black and pink. The chest is bright purple and has spikes to protect themselves against other flies. These insects like to fly in packs in order to detect possible prey more efficiently. If one fly detects food, it will disperse a pheromone which will alert the others to the meal. (Wikipedia)