Wigglers, known as Hanachan (ハナチャン?) in Japan, are caterpillar-like creatures with a segmented body and a large nose. They are typically yellow, but turn red when angered. Wigglers are depicted as normally being calm and happy, but when angered, become dangerous and run frantically. They first appear in Super Mario World, and have appeared in several other games, including the sports games in the Mario series. In Super Mario 64, Wiggler is the boss of Tiny-Huge Island. In Yoshi's Story, large, fluffy versions of Wigglers appear often. In Mario and Luigi: Bowser's Inside Story, a family of Wigglers lives inside Dimble Woods; they are farmers of vegetables.

In the Super Mario World animated series, they are referred to as "Caterpillars" and appear in the episode Mama Luigi.

In New Super Mario Bros Wii, there are bigger versions of Wigglers called Mega Wigglers that Mario cannot defeat. If Mario attempts to defeat them, they might damage him. Wigglers were first playable in Mario Power Tennis for GameCube. They also reappear in Super Mario Galaxy 2. Wiggler is also a playable character in Mario Kart 7.