Turns out it was a snapping turtle, but it is not known in that part of the world:
A fisherman in China was surprised to catch a mystery creature which looked like a cross between a dinosaur and a turtle.
Sun Yongcheng's catch, in Weishan Lake, Anhui province, was later identified as an alligator snapping turtle, which is not native to the country.
The species is only native to North America and was probably someone's pet before being dumped in the lake, the local fishing department said.
More here, with photo, and the turtle does look like something like an alien dinosaur!
reposted on Animal Forteana