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The male has a hollow belly shield, while in females it is flat. And males have longer tales than females.
Look at the bottom of its tail, if there's a hole closer to the tip of the tail, it is a boy, if its closer to the body, its a girls.
Female turtles have dull colors and male turtles are much brighter and can sometimes be smaller too.
Males are normally very attractive (mostly for mating reasons) but it is hard to tell..If you are buying a turtle as a pet then ask the worker, they usually know what gender it is!!
They have a different marking on their stomachs. Would not recomend turning them to fell for the sign though.
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