Cerebore
The Cerebore is a large Tyranid organism equipped with sacs to transport smaller creatures into battle, similar to the roles fulfilled by the Haruspex...which is like the complete opposite in reality as it is more closer to the Tervigon than anything else. It is equipped with a hardened exoskeleton on its back for protection and multiple tentacles to fend off attackers.
The Cerebore seem to be more sluggish in both appearance and movement albeit more armoured compared to the walking uterus that is the Tervigon, so their battlefield roles could be that of a heavy duty troop transport carrier that may carry more units than the Tervigon at the expense on not having the ability to birth out Gaunts like flashlights and the speed/maneuverability.