Darkling

From Wikitroid, the Metroid wiki

Darkling is a Luminoth term used for describing Ing-possessed creatures. This tends to greatly increase either their health or their attack, while making them highly vulnerable to light. Most Darklings have Aether counterparts, such as the Dark Splinter and the Splinter. The only way to seperate an Ing and its host without the Ing wanting to is to kill the host, and the Ing with it. It is unknown if any Darklings survived on Light Aether when Dark Aether collapsed, though it is a possibility. The Nightbarb is a odd darkling because the only Nightbarbs that aren't darklings are on Bryyo which is very far away. It is a possibility that the Nightbarbs where on the leviathan one way or another. It is also a possibility that the Nightbarb populations on Aether where very low and when the Ing first experimented with possessing other lifeforms that they possessed all of the Nightbarbs.