Where are you located? Could you post some more picture? From the bottom,face etc?
It's was in a pond in Bangalore (South India). Sorry I don't have any other pics.It might be a baby Reeves turtle, but it's sometimes hard to tell hatchlings species. It would help if we knew where the pond is geographically.
Very difficult to tell..
I'm between pyxidea and melanochelys trijuga
But you say it you found it in the south and there arent pyxidea normally. In the south you only find melanochelys.
Maybe maybe maybe it could be geomyda sylvatica but the chance to find such a endangered species in a random situation is really small. So without more pictures I can't help you more sorry.
I'm with Melanochelys trijuga - Indian Black Turtle
ThanksA very warm welcome to the forum.