These are on Genesis: Part 1, but Dododex doesn't have them in that section. They're in the bog biome. Like so Dododex sees and can change this! And the reason I know this is That I was killed by them thrice in a row.
NEVER UNDERESTIMATE THESE BUGS!!!
In a high graphic environment, these guys can go unnoticed and, if the whole group of soilders and drones is upon you, can kill beginners with ease.
Advise: these guys rely on surprise and so if you realise your under attack run away and turn round, they easily die if they are kited