CHICAGO (AP) — Footage of a plump snapping turtle relaxing along a Chicago waterway has gone viral after the man who filmed the well-fed reptile marveled at its size and nicknamed it “Chonkosaurus.”

Joey Santore was kayaking with a friend along the Chicago River last weekend when they spotted the large snapping turtle sitting atop a large chain draped over what appear to be rotting logs.

He posted a jumpy video of the turtle on Twitter, labeling it the “Chicago River Snapper aka Chonkosaurus.”

In the video, Santore can be heard sounding stunned by the size of the turtle, which was displaying folds of flesh extending well beyond its shell.

“Look at this guy. We got a picture of this most beautiful sight. Look at the size of that … thing,” he says, using an expletive. “Look at that beast. Hey, how ya doing guy? You look good. You’re healthy.”

Chris Anchor, the chief wildlife biologist with Forest Preserves of Cook County, said the snapping turtle Santore filmed is quite rare, considering its apparent size. He said it’s also unusual for the reptiles to be seen basking along rivers, but it probably recently emerged from hibernation.