Oh god... I absolutely hate roaches... But they fit so well in Super Metroid, along with the other creepy crawlers.
On a side note, weren't these little bastards also in Metroid Fusion? The things that float left and right, and you can use them as platforms by freezing them, but can't even damage them? They look similar...
As far as I know, these particular critters only appear in Super Metroid and can be seen crawling around the walls of Crateria, the dead guy you find right before Kraid, and on the crashed ship before you defeat Phantoon. [link]
It's a Galactic Marine from the Metroid Prime Series. Surprising you haven't heard of them and confused it for Halo; Metroid Prime seems to be one of the more popular Metroid games to the general public.
I am well aware of the Galactic Marines. But there is a dead character in one area of Super Metroid that is wearing this or similar armor. No explanation is given for its presence, but it's there. I didn't really think this was Master Chief, I was joking, because they look similar.