It looks like a yellow belly slider. When it's head is out is there red where it's ears would be? If so it would be a red eared slider. But I think it is a yellow belly. What a cute little turtle. I have one just like it except it has the red ears. Make sure it's water is about 78 degrees so that it will eat. Have you had turtles before? If not please check out some of the people on the boards tanks. Turtles are not cheap pets to keep. Setting up a tank can be cost a bit. But it's so worth it. Turtles can be great pets. Good luck and keep us posted.