The Flea is a vermin flea that Sandy picked up while visiting Texas and brought to Bikini Bottom. The flea is known for being able to reproduce in rapid succession, causing an infestation within Sandy's Treedome. The flea caused pain to SpongeBob, Patrick, and Sandy by continuously biting the three. The flea's attacks are eventually countered by Sandy's flea proof collar. However, the collar was destroyed during the multiplication of the fleas. The flea's only appearance is in the episode, "A Flea in Her Dome."
The flea appears to have a large, red body. It has two long legs and four short legs. It's head consists of small yellow eyes, and long antennas.