Heterocheila

Heterocheila is a genus of acalyptrate true flies (Diptera). They are placed in their own family, Heterocheilidae, in the superfamily Sciomyzoidea. They are not widely familiar outside entomological circles, but the common name "half-bridge flies" has been associated with them. They are medium-sized flies occurring mainly in temperate regions on seashores of the Northern Hemisphere, where they and their larvae typically feed on stranded kelp in the wrack zone. In this, they resemble kelp flies, which are members of a different family, though the same superfamily.