Atomic

From Wikitroid, the Metroid wiki

An Atomic is an energy-based creature found in Super Metroid and Metroid Prime 3: Corruption. It is virtually identical to the Pulse Bombu of Metroid Prime and the Harmony Class Drone of Metroid Prime 2: Echoes. The main difference is that the variation in Metroid Prime is only vulnerable to the Wave Beam. In Corruption, it can only be killed by a charged shot. They are found in the Wrecked Ship in Super Metroid and on Bryyo in Corruption.

An extremely similar but officially unnamed construct appears in the Space Pirate Mothership in Metroid: Zero Mission. Only missiles and the Screw Attack work against these.