The Fanged River Otter lives 5 million years from now in the Amazon Grasslands rivers.  It is 10 feet long, and as its name suggests, has large fangs.  It has evolved from the Giant Amazonian River Otter and is a fierce predator.  While fast and energetic in the water, while on land it has a hard time moving around.

It eats by engulfing its prey with its anal sphincter and then digesting it alive.