From the Super Mario Wiki
A Pikku (ピック, meaning "Pick" or "Pic") is a leech-like enemy that appears in Super Mario Land 2: 6 Golden Coins and is found only in the last level of the Pumpkin Zone, where the witch is fought. There are only two Pikku found in that level. The Pikku simply hops back and forth, getting in Mario's way. It can be defeated with a single stomp.