Wisconsin status: locally common
The northern map turtle looks quite a bit like the other map turtles, but there is a difference. It has a uniformly-colored yellow or creamy plastron (bottom shell). The others have blotchy plastrons.
This turtle has a very slight raised ridge (keel) that runs down its back. Its carapace (top shell) is olive brown and is patterned with fine yellow lines that look like a road map. Its head and neck are olive-brown with thick yellow lines running from the head to the the neck. It has a yellow spot behind each eye (check out the photo). The back edge of the shell is somewhat jagged (serrated in biologist terms).
The menu for this critter includes insect larvae, carrion (dead things), crustaceans, and aquatic plants. This is the range map for the northern map turtle--range is in brown. The females have large broad heads and jaws adapted for cracking mollusk and crayfish shells. Ouch!
They like to live in habitats with slow to moderate current, soft bottoms, and lots of aquatic vegetation. Side channels off of large rivers, backwaters, and some rivers and reservoirs are home to this turtle.