1. White Xenomorph
Created by a corrupt artificial intelligence called T.O.Y they were genetically engineered to work directly for T.O.Y. They used white Xenomorph face huggers to impregnate real Xenomorphs. They were so dangerous that it forced Xenomorphs, Yaujta (Predators) and humans to all work together to kill them all and stop T.O.Y.
Alien vs Predator wasn't classified as being a sound franchise but it did introduce an interesting being to us which was the predator and Xenomorph hybrid that came about when in the first movie one of the Predators was somehow impregnated with a chestburster. This created the Predalien hybrid that was luckily killed by a Predator in Alien vs Predator 2 but it might've really been killed by the bomb that the Government dropped on the town in which their confrontation took place.
3. Queen mother
We've all seen the queen Alien. The one that lays the facehugger eggs that when hatched launch themselves at the nearest living thing and impregnate them with chest bursters that launch out of the chest and quickly grow into Xenomorphs. The Queen mother is the one that lays the Queens. It's the supreme ruler of all Xenomorphs and even queens are completely subordinate to the Queen mother's rule.