No mysterious creature.
It is a tadpole shrimp.
We have them here in Texas in an at-times dry lake. When we get heavy rain they hatch out.
Yep, also known as triops.
"Over the last two days, Ive been getting inquiries about the identification of two objects in some recent photographs.
One supposedly cryptid that has been shown to me is this animal (below) being featured in the Russian media. Said to be a Prehistoric Fish, it reportedly was found in Russia, during construction near an underground river in Chelyabinsk city. The workers killed it and these are the remains.
Apparently, someone is having a little fun with pictures and sizing. This animal is actually a small species, the Triops (notostracans), the so-called tadpole shrimp or shield shrimp. While an aggressive predator, they are smaller than what Pravda (hardly the truth) would have us think.
The Triops grows to an upper limit of 22 millimeters or 0.8661417314 inches in length. The Pravda photographs give an illusion this animal is much bigger.
Triops or notostracans are intriguing, no doubt about it, though. I like what it says here in their description: Triops cancriformis may therefore be the oldest living animal species on earth. Heres a less dramatic photograph: