I managed to capture Arthron, so I would assume I know how to catch a specimen. Injure it to low health, hit it couple of times with neuralizer, remember to build and power up alien containment.
I tried to catch tritons on a base defense. neuralized one, but did not get the research. Reload and neuralize 2, still got no research.
Made sure I flew to the base with containment, still no research.
Maybe the containment was full (with 1 arthron??). So I powered it down, to kill the alien if it hasn’t died during the vivisection, then flew to the base. Still no Triton vivisection research. So what gives?