Being one of the first civilizations I think it would be cool to name them after a Mesopotamian (one of the earliest civilizations) god who is also mischievous and can use "magic" that could be a vocal point of theire story and since he resides in the ocean that could be theire home planet and perhaps like in meso/sumerian mythology they gave knowledge to the first races but instead had it stolen and there kindness was forgotten by both sides and they needed other races to know of them  so they are in many ancient text. (like they are thought powered or something maybe the more minor/major races you encounter/assimilate slightly increases production yield or a special abilty)