Males and females of the same species are similar in appearance. Adult syrphid flies range from 1.0 cm to about 2.5 cm in length. The body color of these flies is usually black or brown, and marked with white, orange or yellow brightly colored bands. These flies resemble bees or wasps in appearance. The eggs of syrphid flies are a chalky white color and contain very faint ridges on their exterior. Larvae can attain a length of up to 1.2 cm, and look wrinkled or slug-like with a tapering anterior body shape. The larvae range from brown to green in color, and display white markings along the body.

Syrhid flies usually overwinter in the soil as pupae. Adults are active around April or May, around the time that aphid populations begin to increase. Syrhid flies lay their eggs singly on leaves, flowers, and stems of plants with high insect populations. Larvae will emerge from eggs three to four days after they are laid, and will feed for up to 10 days. The larvae fall to the soil, pupate and emerge as adults within 16 to 28 days.

Adult syrphid flies are found throughout the United States around flowers, but some species are found in woods, moist areas, in fields and vegetable crops, and near aphid or ant colonies. Larvae of syrphid flies are found in nests of ants, termites, bees, in decaying vegetation, on injured plants and bulbs, and in aphid colonies.

The larvae are considered ferocious predators of aphids on vegetable and field crops.

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