All this talk got me playing another game. After I think 8 or 10 replays, I finally figured out how to kill those bastard lava lizards. My trusty knife wasn’t doing anything. I think it was because they were impervious to heat.
So this time they were really annoying me while I was drilling for kyanite in my prawn. I stasis’d them, and killed them pretty quickly with the drill arm on the prawn.
Edit: I hated this lava lizards so much that one game I collected their eggs and bred them solely to feed them into my bioreactor. lol