Due to the highly caustic and irradiated surface of Site Delta, the only major flora that appears to have evolved in the hostile environment is a form of fungus that builds up in colonies around recessed pools were concentrated acidic fluid compounds collect. The fungal colonies feed on the acids with a process the produces hydrogen and sulfur byproducts, which leech upwards through the fungal structures and create floating orbs with thin membranes that are full of gaseous hydrogen sulfide. These occasionally rupture explosively, spreading fungal spores further throughout the otherwise barren landscape. Further study likely to only be of interest to xenobotanists. No clear military value.
SITE WARDEN NOTES: "No clear military value" except they make the lowlands completely unassailable - one stray shot will set off explosions across dozens of acres. It would take an idiot to risk pulling a trigger down there. Anything you want to protect from being physically captured is pretty safe there, except from orbital bombardment.
If you need a model of alien fauna that is both bizarre and unnerving, a floating orb of explosive, caustic vapor is just what you need and this is that thing. This will need extensive supports during printing so make sure those are well tuned before slicing.