It's 2,350 miles long, spans 31 US states and is home to a 100kg animal with a tongue that looks like a worm

The Mississippi River flows for around 2,350 miles through the heart of the US. It drains an area of 1.2 million square miles – that's roughly 40% of the country – and at certain points is 11 miles wide. It is North America's second longest river, behind the Missouri River.

Rising from Lake Itasca in Minnesota, the Mississippi winds southwards through a range of environments, draining water from 31 US states before reaching its delta at the Gulf of Mexico in Louisiana.

The sheer size of the river and the diversity of habitats it passes through make it a refuge for a huge range of animal species, including more than 260 fish, 326 birds, 50 mammals and at least 145 amphibians and reptiles, according to the National Park Service.

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There are many weird and wonderful animals living within the Mississippi's vast waters, but surely one of the strangest is the alligator snapping turtle.

This prehistoric-looking reptile is massive. It can weigh up to 100kg and males can grow well over half a metre long, making it the largest freshwater turtle in North America. 

And as if its size wasn't enough, the alligator snapper has a host of other characteristics that make it one of the Mississippi's most striking creatures, including a dark, spiky shell (known as carapace), a brick-like head and a sharp, hooked beak. With such a formidable appearance, it's easy to see how the turtle got its 'alligator' name.

But perhaps the turtle's most curious feature is a worm-like appendage found on its tongue, which it uses as a lure to catch prey, such as fish, amphibians and invertebrates. Alligator snappers are also quite happy scavenging for food.

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