An order of actinopterygian fishes that comprise, with the Atheriniformes and Cyprinodontiformes, the series Artherinomorpha. These fishes are identified by the interarcural cartilage that connects the first and second gill arches; small second and third epibranchials; absence of interhyal; a nonprotrusible upper jaw; far posterior placement of the dorsal and anal fins; abdominal pelvic fins; and the lower caudal fin lobed with more principal rays than the upper lobe and significantly longer in needlefishes and flyingfishes. The order consists of 191 species in 38 genera and 5 families. Each family has distinctive features that make identification simple.