BEAUTIFUL!
I myself am avery big Metroid fan, and I love your super realistic approach to this iconic beast. But as I'm sure others have stated, metroids don't eat flesh. They are basically a recharable battery, they'll take the energy they consume and use it until they need more.This is where the battery similarites end. After they absorb enough energy, they will mutate into a new form. Problem is, no one has figured out how to extract the energy from the metroid, because no one knows what the energy is, so they aren't a very good source of power. You are proabably right with the electrical charges from the nerve system. You also neglected to mention that metroids can asexually reproduce when exposed to beta rays or phazon. Any ways, they art itself is absolutly amazing, although, the description was a little off. So 9 out of 10.