This is a member of the Marsh fly family, Sciomyzidae. Fairly large group with about 200 species in the US. Most have spotted or patterned wings and the antennae that extend forward. They tend to live near water environments and the larvae feed on snails and snail eggs, some on slugs.

This is another striking Marsh fly. Much larger than the above. I believe it is in the genus Euthycera. In a snail rich creek area in Searcy county. About twenty genera of Sciomyzids in the US.