The Pennantfish is a diamond shaped silver fish. Juvenile Pennantfish have long filaments trailing from their dorsal and anal fins. Adults do not have these filaments. Their are two species of Alectis in Australian waters. Alectis indica (the Diamond Trevally) has a more angular head than the Pennantfish, and juvenile Diamond Trevally have filaments on their pelvic fins.
The Pennantfish is found in inshore waters and continental shelf waters in depths from the surface to 100m deep.
The Pennantfish is found in tropical and warm temperate waters around the world. In Australia it is found from south-western Western Australia, Northern Territory, Queensland and south to the southern coast of New South Wales.