ANTHOMYIID FLY

a common insect of the family Anthomyiidae (order Diptera) resembling the housefly in appearance. The lesser housefly (Fannia canicularis) and the latrine fly (F. scalaris) are important anthomyiid flies. They breed in filth, can carry diseases, and are often found in the home. Some larvae feed on plants and are serious pests, many are scavengers and live in excrement and decaying material, and others are aquatic. Among the larvae the cabbage maggot (Hylemya brassicae), an important pest of Canada and the northern United States, attacks the underground parts of cabbage, cauliflower, broccoli, radishes, and turnips. It was introduced from Europe early in the second half of the 19th century. The best control is treatment of the soil with insecticides. The onion maggot (H. antiqua), found in North America, injures onions by feeding on the underground bulb and stem. The adult is a bristly, gray fly about 6 or 7 millimetres (0.2 to 0.3 inch) long with large wings. It is best controlled by chemical applications before planting. The seed-corn maggot (H. cilicrura) feeds in corn, pea, and bean seeds, which consequently either develop into weak plants or fail to sprout. This species has a short life cycle and produces from three to five generations each year. Damage caused by the seed-corn maggot can be reduced by delayed planting. Another important pest is the spinach leaf miner (Pegomyia hyoscyomi). It produces blotches or linear mines (internal passages) on spinach leaves.