Anguillian, an eel-man from the deeper depths of the oceans:
I used these in an adventure in my last campaign where the PCs were looking for the phylactery of a lich. Said phylactery was hidden in a cave system deep within an aquatic trench, with a bunch of anguillians as unwitting guardians.
Johnathan
P.S.: I'll be posting infrequently for the next week or so - I'm on vacation, visiting the wife's relatives, and will have limited access to a computer.