Alert, Genetic imperfections detected among population, possible Unauthorised Procreation committed...

"Protectione team alert, biosignals of individuals for PCIDs transmitted to your HUD scan imperfect genes. Subject is confirmed non-perfected individual. Possible genetic malmatch through non authorised procreative activity. Code: Inquire, Prosecute, Confirm." Overwatch said to them, as the units prepared their weaponry. The Collective law code actually forbade reproduction without the consent of the state, given on a case to case basis to prevent the formation of imperfects. If an imperfect couldn't be cured, full amputation from civil society was the appropriated treatment.
Effectively, the genestealer cult had been identified and branded as Imperfects due to their Genestealer DNA, the biosignals readings would constantly state that the genes were nonstandard. As a result, the subjects were slated for amputation

The APC rode forwards, the individuals activating the biolocks on their weapons, which scanned their DNA before linking it up to their integrated HUD. Hardlight pistols, electroshock batons, anti-personal pulse grenades... And the squad leader had a light hardlight rifle. Not what one might consider military grade, but considering the effect of the hardlight rounds on even armoured targets, they were still dangerous. Shots had been known to remove limbs entirely, and the shot almost never failed to punch straight through the target. It was, after all, travelling at the speed of light to its targets.
And as this was a Saeva Simius new world, those holding then were the massive apes. The worlds gravity alone was .2 G lower than what they were used too, and it was still 3.8G. These were known, unaugmented, to be able to tear a man limb for limb with relative ease. 
The apc arrived at the location, its dark energy machine gun scanning the area. The six Civilis Protectione units poured out of the back, their squad leader watching his motion tracker while the 02 linked the bioscans with their HUD integrated tracking device
As for detecting the fleet its self, unconventional means achieved that. This was, after all, a massive psionic signal, flying across space. There wasn't a Triarian Watcher alive who was going to fail to report that to high command, conventional means be damned. And the response was appropriate.
"Attention all ground, defense and space units, arm planetary defence grid and prepare for exogen infection. Code: Inoculate, Cauterise, SWORD. Inoculation code: Steriliser, Viscerator, Bouncer. Force deployment code: Non-Surgical, Zero, Zero"

Equestrian transport ship

The Equestrians would make a shocking discovery come morning, when it turned out the transport ship they had used to get to the Triarian planet was now partially eaten and had areas of an odd biological substance on jt, with little worm like creatures apparently trying to eat the ship. These were, in fact, Larvae for a somewhat larger creatures. They were known for infesting and eating devices they came across and there werre entire procedures dedicated to detecting and removing them on Triarian worlds, due to an infestation in the past which resulted in several ships being damaged by the ravenous creatures

Triarian subspecies

All genetic markers in the male pointed to what the Collective would easily deem imperfection. His sensory systems were not properly developed, only one of his lungs workered, only one of his two livers worked, and his nervous system was slow in comparison. Atop of this, he seemed to possess, a lowered level of intelligence which pointing to a child having been born extremely prematurely and somehow having survived. Dozens of other problems plagued it, mostly from under development. Yet it had an unnerving way of having survived so far, and seemed rather content. Externally it could be mistaken for being as healthy as the others, if only it could see.