I have thought of this a couple of times, but never got anywhere with the idea. It would probably be the purest form of Xenomorph imaginable, It also might see other xeno's as host fodder. That's about the Xeno spawned xeno, but the facehugger spawned xeno would be scary as hell. It would probably have between six and eight limbs, and it might have a proboscis for host impregnation, instead of or in addition to the regular tongue. Interesting idea, might happen rarely during hive wars.