The Magela hardyhead (Craterocephalus marianae), Mariana's Hardyhead, or Jaidenlal findius is a species of fish in the family Atherinidae endemic to Australia. It has a very restricted distribution, only found in the Alligator Rivers region of the Northern Territory where it inhabits shallow and fast-flowing freshwater creeks. The fish has a high thermal tolerance, like some other species in the genus Craterocephalus, and may tolerate water temperatures up to 39.5ú. The specific name honours Walter Ivantsoff's daughter, Marian.