Pteronura Brasiliensis

Giant River Otters live in rivers of various rainforests. Now they have adaptations like webbed feet to help them swim. They have short but dense coats. These prevent water from reaching their skin. Their ears and nostrils close when they're submerged, keeping water out of them. They have acquired scissor-like teeth to rip food. Due to climate change rainforests will become an expanse of shrubland because of forest degradation. Rainforest plants can't survive in that environment. There will be some saltwater lakes due to sea rise. They will need a bigger stomach to fit a filter. The filter will clean saltwater so they can drink it. They'll also have to have vegetarian teeth; they'll not be able to eat their regular food. They'll have to eat shrubs. They'll need sharp claws to cut shrubs to eat. That's how Giant River Otters will survive.