hardyhead
/ˈhɑːdɪhɛd/(also hardihead) originally Australian
noun
Any of various small silvery fishes of the family Atherinidae; especially the marine fish Atherinomorus lacunosus of the Indo-Pacific, and freshwater fishes of the genus Craterocephalus, which are endemic to Australia and New Guinea.
Origin
Late 19th century; earliest use found in Proceedings of the Linnean Society of New South Wales. Probably from hardy + head.