Moto as it appears in Metroid II
A Moto is a creature native to SR388 that is found in Metroid II: Return of Samus and Metroid Fusion. They have a mask-like structure with horns at the top covering their faces. In Metroid II, their Artificial Intelligence is to walk to the right a set amount and then to walk to the left the same amount. Their backside is most vulnerable to attack. In Metroid Fusion they were infected with X like the majority of the creatures. If it sees Samus, it will charge at her. Shooting enough at its backside or shooting a Missile anywhere on its body will kill it.
X Parasite infected Moto.
Trivia
The Helmasaur and Helmasaurus from the Legend of Zelda series, closely resemble the Moto in appearance.