A recent study suggests that the “dinosaur of the turtle world”, the alligator snapping turtle (Macrochelys temminckii) is actually three separate species. Read abstract. Alligator snapping turtles are the largest freshwater turtle in the Western Hemisphere and can weigh as much as 200 pounds. They are a long-lived, up to 100 years, apex predator that’s found in the river systems that drain into the Gulf of Mexico. – Leer más.