What is "spiny softshell turtle"

n. A type of soft-shell turtle native to Canada, the United States and Mexico, having spiny projections on the leading edge of its carapace.

The spiny softshell turtle (Apalone spinifera) is a species of softshell turtle, one of the largest freshwater turtle species in North America. They get their name from the spiny, cone-like projections on the leading edge of their carapaces, which are not scutes (scales).