The aqua alien was a figure from the 1997 Alien Resurrection line, it came with a miniature of the Betty. It's generally considered to be the most popular of the line, below is the blurb from the box.

"The future: An old enemy, the perfect predator. A zealous assembly of scientists is conducting an experimental wedding of human and alien genes... the result is a peril reborn and more shockingly monstrous than ever before!"