Featured flying glow-in-the-dark creatures that resembled sand dollars. They flew through the air -- like little throbbing, glowing flying saucers -- landed on people and sucked their blood dry. I assume they were aliens. All I remember is that they were fluorescent green and landed with a splat. Does anyone recall the name of this film?

I have asked this question before and received several replies, none of which were the movie in question.

Previous (incorrect) suggestions:
Abyss
Alien
The Arrival
Deepstar Six
The Evil Below
Fiend Without a Face
Leviathan

Lords of the Deep
Night of the Creeps
Puppet Masters
Slither
The Thing