I recently bought this fish from Petsmart. The employee said it was a platy and ended up picking a random sku because she didn't know which breed it was. I was thinking it was a very large female guppy but she's a lit bigger than guppies I've raised. (2in. in length) The black spot seems to be coloring and not a gravid spot, but not sure. Could it be a platy-guppy hybrid or is it just a big lady that super pregnant already?