Grubby

A Grubby is a spiked form of Unera. They are best described as bee larva with oddish spikes covering their bodies, and they appear in the Tree Zone, during the events of Super Mario Land 2: 6 Golden Coins. They can be defeated by hitting a block they're on top of or by using a Star.

Super Mario Land 2: 6 Golden Coins

 * Virtual Console Manual: "This is a slug with a stinger. Don't tread on this grub, as its sting is really powerful."