Pictures of Alligator Snapping Turtles (Macroclemys temminckii), a massive freshwater turtle that has a specialized tongue impersonating bait.
Here, in an aquarium, you see him showing his tongue in an attempt to get food to swim into his mouth to easily eat it. I think he thought the finger was food.
This is the largest of all freshwater turtles found in North America. They inhabit rivers, lakes, and canals of the Southeastern United States. Large males may exceed 200 pounds, while females max out at 50 pounds. They can live up to 100 years. Its tounge sports a bright red worm-shaped piece of flesh that when displayed draws curious fish or frogs close enough to be snatched up. They are considered a threatened species due to over-harvesting for its shell, meat, and the exotic pet trade.