Found some more ten year old images, this time a squadron of Silent Death figs I'd forgotten about.
These are sold as Worm Pods.
In Silent Death they're fancy boarding pods, delivering bio-engineered crew-killers to enemy ships - which is how the Night Brood dealt with the much larger human warships.
Unsurprisingly, I mostly used them for Tyranid escorts in Battlefleet Gothic or as smaller astrofauna in Full Thrust and Starmada.
If I had them to do over again I'd probably go with a color scheme that makes them look less like the unholy spawn of Cthulhu and a cabbage, but a decade ago it seemed like a good idea.
I've also added these images to my old Silent Death gallery for completeness.