Plasma turret dismounted, which falls into the support category of weapons with the Missile Pod, Chain/Machine Gun, and possibly more we don't know about yet? Doubtful, but....
LOL ok everyone who said its a mauler needs to read its already been confirmed its a plasma cannon but omg after he tells you lol you say 0m9 1t5 a Mau13r!!!
Well, now that we've established its not a Mauler...
Your right, its a plasma turret, like the ones the grunts used from H2, but in that screen the legs are not unfolded. So it's not so-unidentified now, eh?