The Nommo is the name the people of the Dogon tribe in Mali give to an amphibian race (said to be half man, half fish) of alien visitors from Sirius.
There are strong similarities with the Babylonian water god Oannes who was also said to be half man, half fish.
Note that the monolithic 'El Friale' statue in Tiahuanaco, from the waist downwards, also wears a garment meant to represent fish scales, each one carved into a tiny fish head.
A similar monolithic statue has been found in the now submerged site of Nevali Çori in Anatolia (Turkey).