Does it say "Spit poison" or "spit acid?" on that ability? If it's acid, no problems. If it says poison, it needs to be changed to acid.
I used the studded collar to control an albino rock spider (they're awesome on your team), so I'll have to check on it. I think it says spit acid.
Even if it does spit acid, though, the affect is just like poison since it damages the unit each turn.
