The Bellyburster is a Xenomorph infant, that bursts from the victim's abdomen.
Using a delivery method similar to a Facehugger, The Predalien (Earth) the could force embryonic Xenomorphs down its victim's throats. The victims appeared to be only pregnant females, as the Predalien merely killed a female nurse instead of implanting her. Multiple larvae later erupted from the victim's abdomens. Functioning as a juvenile Queen, the Predalien utilized these multiple spawnings to quickly increase the Xenomorph population and build the Hive, presumably before molting into a full grown, Egg-laying Queen.
Behind the scenes
- "The belly bursters were actually in the first draft that Colin and I read...They had the bellybursters ... caused by an alien warrior...We actually made it the Predalien that was reproducing in this fashion" -Greg Strause AVP-R: Preparing For War: Development and Production (featurette)
- "Basically the Predalien's kind of a baby queen-there's a phase in between warrior alien and full-blown queen...they do this thing with embryo implantation.. the idea with that was; how does a baby queen quickly form her own little mini-drone army to get the hive built before she evolves into the final state where she can't completely defend herself?"--Colin Strause AVP-R: Preparing For War: Development and Production (featurette)
- The Bellybursters are closer in appearance to the Chestburster from Alien Resurrection, with a much wider, larger mouth.