The Ulidiidae (formerly Otitidae) are a large and diverse cosmopolitan family of flies (Diptera), and as in related families, most species are herbivorous or saprophagous. They are often known as picture-winged flies, along with members of other families in the superfamily Tephritoidea that have patterns of bands or spots on the wings. Some species share with the Tephritidae an unusual elongated posteroapical projection of the anal cell in the wing, but can be differentiated by the smoothly curving subcostal vein. Two species, Tetanops myopaeformis and Euxesta stigmatias, are agricultural pests.