What is "acanthochelys"

Acanthochelys is a genus of turtles, the spiny swamp turtles, in the family Chelidae, subfamily Chelinae, found in South America. Until recently, the species of this genus were considered to be members of the genus Platemys, but were moved to the resurrected genus originally described by Gray (1873) based on the type species by monotypy Acanthochelys spixii.