Kleptoad

Kleptoads are a type of enemy appearing in Super Mario Galaxy 2. They only appear in Hightail Falls Galaxy in the "Silver Stars in Hightail Falls" mission. They are little blue frog-like creatures that jump and also burrow into the ground and appear out of a random spot similar to Gobblegut. Sometimes, they have a type of item above their heads and try to keep it by jumping. When an item is on the ground, they might pick up the item and try to keep it. Also, if one dies, another will try to pick the treasure up. They can be destroyed by having Yoshi eat them or jumping on top of them.

Trivia

 * Kleptoads resemble Poliwhirl from the Pokémon series.