Moldworm

Moldworms are Minish-sized enemies in The Minish Cap. They seem to hold a symbiotic relationship with Pestos because when Link gets all dirty by being eaten by a Moldworm, any Pestos in the area are attracted towards Link more quickly and attack more often as compared to when he is clean.

Trivia
Sandworm, the giant worm-like enemy in Phantom Hourglass, is called Moldworm in Japanese.