Drill Parasite

The "Drill Parasites" are light blue parasitic creatures that are shaped like small drills. They resemble starfish when unraveled, and even have an opening in the middle of their undersides, similar to that of real starfish.

"Arcade Mania"
After the defeat of the bigger Gem Cave Creature, the drill parasites managed to escape by drilling away into the ground. They returned when Steven was scanning the beach for quarters, and infested the city. It took all day for Garnet, Pearl, and Amethyst to destroy them all.