Gold Scisers were a variant of the Scisers which were clawed aquatic predators native to Zebes. They can be found in Sector 4, and as their name suggests, are gold in coloration. When a free-floating X Parasite comes in contact with certain Scisers, they transform into these life forms and are capable of firing golden orbs from their claws. They are more powerful than their average counterparts and have developed an immunity to uncharged beam shots.
It is unknown what triggers the creation of these gold variants. Another similar case is the Gold Space Pirate. Metroid Fusion: The Official Nintendo Player's Guide refers to them as a "gold-colored crab".