Marsh flies are generally slender, yellowish or brownish, 1/4 - 1/2" long. They have fairly prominent eyes, prominent forward-pointing antennae, and bristles on the femora (upper hind leg). The wings are mottled with various light brown markings according to species. Marsh flies are common along the edges of ponds and rivers, and in marshy areas where the larvae prey on or become parasites of slugs & snails.

Habitat: Near ponds, streams, marshes.
Range: Throughout North America.
Food: Adults drink dew, nectar, and tree sap. Larvae prey on slugs and freshwater snails.