Chelodina, collectively known as snake-necked turtles, is a large and diverse genus of long-necked Chelid turtles with a complicated nomenclatural history. Although in the past Macrochelodina and Macrodiremys have been considered separate genera and prior to that all the same, they are now considered subgenera of the Chelodina. Macrodiremys is a monotypic genus recently split off from the rest of the Chelodina. Its sole member is the enigmatic Chelodina (Macrodiremys) colliei from Western Australia.