The Kraathatrogon are a species of worm-like creatures from Dimension X, who secrete Mutagen.
The adult worms can reach the size of 100 feet long.
They are vunerable to salt.
They have a weird simian face in the tip of their tail.
The Kraang milk'em for mutagen as if they're cows.
The Kraathatrogons have two antennas which the Kraang (and April) use to ride them.