The Raptoids are the "grunts" of the Aesteron army. Their rankings are apparently distinguishable by their color(see chart below). The ranks range from the front-line soldier to the army commanders.
Raptoid Ranking Chart
Brown - Soldier or Grunt Red - Security Drone Blue - "Heavy" troops (usualy fitted w/ large or powerful weaponry) Green - Scout Gold - Commander Silver or Grey - Feild General White - Pilot or Artilery Gunner