"The Unggoy (Latin, Monachus frigus, meaning "cold monk") are a species of squat bipedal vertebrates, (commonly misidentified as arthropods)," Warrior stop being wrong in your wrongness!
Pardone moi, but check the Halo Encyclopedia. Latin names aside, Bungie clearly state's that they are Arthropods. I hate to go all halo guru/freak but I can't help it.