-Bloo-,
Xenomorph,
13 years ago
So far, a Praetorian has never appeared in the films - however, if you're like me and wish it was official, the most logical way to think about them is that the name "Praetorian" is simply given to an underdeveloped Queen/Empress. No special morphing, no "official guard" status... Think of it this way: Teenager = Praetorian, Adult = Queen.
I'd also consider the director's cut of Alien 3 to be canon, mostly for the reasons Dave's already said.
As for the Super Facehugger, I remember a topic from a few years ago that showed the differences - mainly in size - between a normal Facehugger and one that's, well, super. It's entirely possible that it could hold two embryos, being that it was much larger than the standard. Also, it was a scary looking fucker - webbed legs and colored black if I remember right.