Vathori
Vathori is a planet whose native inhabitants merged their own genetics with that of the Swarm following a failed invasion.1
History
In ancient days, Vathori's people created the Aegis, a planet-wide force shield that could be raised in response to incoming invaders, in order to fend off violent neighbours from a nearby planet in the same solar system. A few years after the raiders built their first Drift engines, the Swarm came without warning to Vathori from an unexpected direction. After exterminating and devouring the raiders, the Swarm fell upon Vathori. The Aegis was only raised after the Swarm's vanguard landed on the planet, at which point the greater part of the Swarm, unable to sense its missing components through the Aegis, left Vathori, leaving the vanguard fighting the Vathorians.1
Vathorian scientists came to believe that victory was impossible, but instead of surrendering, they devised a virus to be used as a genetic weapon. As the Swarm adapted, the virus mutated in response (possibly under an external influence) and rewrote the genetics of all creatures on Vathori, merging natives with the Swarm.1
Inhabitants
All fauna and some flora on Vathori are now partially insectile, from scuttling herd animals to myriapod-like snakes. The modern Vathorian people are humanoid insects, and honour both the statues of ancient Vathorians and fossils of Swarm carapaces. The Aegis has been shut down by threat assessors long ago, and many other peoples have made first contact with Vathorians. Some xenobiologists are concerned that the Swarm hive mind might re-assimilate the Vathorians, but some shirren priests of Hylax claim that what happened on Vathori was a miracle and might indicate the possibility of the Swarm's peaceful integration with the rest of the galaxy.1