An Apkallu "fish-man"
Apkallu (Akkadian) and Abgal (Sumerian) are terms found in Mesopotamian inscriptions that in general mean either "wise" or "sage."
these Sages are found in the "Uruk List of Kings and Sages" (165 BC) discovered in 1959 in the Seleucid era temple of Anu in Bit Res; the text consisted of list of seven kings and their associated sages, followed by a note on the 'Deluge.' According to Sumerian legend, Eridu was the oldest city in human civilization, which is still accepted by some modern scholars. Each of the oldest cities in civilization were appointed by human kings and their otherworldly advisers (Apkallu) sent by the gods. These non-human divine advisers were considered to be "half fish half man." After the great flood, human kings no longer had Apkallu rule alongside them. Oannes was the greek name for the Sumerian Abgal Uanna.