Mesogobius nigronotatus
Mesogobius nigronotatus is a species of gobiid fish native to the Caspian Sea. It is only known from a couple of samples, from Kazakhstan and the southern part of the sea; the type material has been lost. It is suspected to be the same taxon as that known as Mesogobius nonultimus.
It has been found at a depth of. The length of the fish was TL.