That is a softshell Turtle.
not sure of the species as i need pictures of its whole body, clear head shot, shell shot...
i can sex it if you can get a clear shot of it's tail, showing its vent
(anus)
Some softshells get MASSIVE, to the point you can't keep them as pets. Most are also really aggressive, worse then snapping turtles... All require a LOT of swimming water & several inches of sand so they can hide.
Offer it some raw fish pieces. It'll also like little live fish to chase too. It'll more then likely eat romaine lettuce.
Once i can id it better I can be more specific on its needs.
I'm not sure if it is a fresh water species, or salt water, so don't give it too much water just yet.
they can also go a long time without eating so don't worry
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