The adult worms can reach the size of 100 feet long or more.
They have a weird simian face in the tip of their tails and two long antennas which the Kraang - and April - use to ride and control them.
The Kraang 'milk ' them for Mutagen as if they are cows.
One of the Kraathatrogon, that April and Casey were riding on, seemingly ate Tiger Claw and was subsequently sent to the 1987 animated series dimension.
A larval Kraathatrogon made a similar purring sound of a cat when it was rubbing against April's butt.