Certain zombies act as hosts to fully-developed queens, and can be seen clawing at the backs of their necks. When Chuck encounters one, it will belch blood on him, causing him to cough and gag. When one of these zombies is killed, the queen is left unharmed, which can be captured by Chuck and used as a weapon.
Later in the game, when the Gas Zombies start to appear, the queens can also be obtained from them, but these ones will try to escape from Chuck by fleeing to the nearest vent.
Primary: Press to smash the jar (and the wasp it contains) to cause zombies within ten feet of Chuck to go into fits and eventually have their heads explode.
Thrown: Hold and throw. Same effect, but at ranged.
Pressing the attack button while standing still is considerably faster in Dead Rising 2 than it is in Dead Rising.
Just like in the original Dead Rising, the jars used to catch the Queens seemingly appear out of nowhere.
Before Chuck crushes the first Queen in Case Zero, he pauses a moment to watch the zombies closing in on him, which suggests he's encountered the wasps before, and knows their effects on the zombified populace; he also does this in Dead Rising 2.
Throwing a queen into gas zombies will stun them, but not kill them.
Shooting an already captured queen in a jar with a gun will cause the jar to break and kill all surrounding zombies. This can be quite a useful tactic in certain situations.
Queens can also be set off using the strong attack of a sledge hammer, killing all zombies surrounding it.
In Off the Record, Frank says "Sure hope this still works."