flies

Diptera is the order of insects that includes gnats, mosquitoes, and true flies. There is estimated to be about 1,000,000 species worldwide, though only about 125,000 have been described. There are about 17,000 species in North America north of Mexico, and at least 500 species in Minnesota. They are widespread and abundant, occurring on every continent, including Antarctica, every state in the United States, and every county in Minnesota. Some are agricultural pests, some transmit diseases. Many are beneficial as pollinators or serve to control other insect pests.

Adults are active from early spring to late fall. They are found in many habitats, always near habitats suitable for their larvae. They are often found on flowers. Some are blood sucking and are found on or near the animals on which they feed. Larvae live in water, soil, decaying organic matter, or plant or animal tissue.

Adults are 1⁄64″ to 19⁄16″ (0.5 to 40 mm) long and relatively soft-bodied. They have a movable head, large compound eyes, and mouthparts optimized for sucking. Most species have 3 small simple eyes (ocelli) in a triangle on top of the head. Their maxillary palps are well developed but they have no labial palps. They have one pair of membranous wings. The hindwings are reduced to small, knob-like structures (halteres). The last part of the leg (tarsus), corresponding to the foot, almost always has 5 segments. The larvae are soft and worm-like. They have no head and no legs.

Sources: 7, 24, 27, 29, 30, 82.

Location: Woodbury, Minnesota