The Larva Guns are seemingly non-sapient creatures native to the planet Vortis in the Isop Galaxy, where they live alongside the Zarbi and act as defenders of the Zarbi nests.
They are human-sized crustaceanoids resembling a flat pillbug with countless tendril-like legs. They also have a pair of huge eyes (presumably to help them find their way in the dark nests) and a narrow, hollow snout from which they shoot blasts of venom which apparently takes the form of a bioluminescent liquid. They are rendered helpless if turned backs on the ground.
Like the Zarbi, the Larvae Guns have had their minds taken over by the malign Animus which used them in war against the Menoptera. After the Animus was defeated, the Zarbi and Larvae Guns are seen living peacefully alongside the Menoptera and the Optera, all ready to give rise to another age of peace and prosperity on Vortis.
The Larvae Guns' true nature remains unknown, as they might represent a distinct life stage or caste of the Zarbi, or a different species altogether which lives in symbiosis with them.