The strongjaw lizardworm has split from its' ancestor, the cave lizardworm. It is named the strongjaw lizardworm because over time, the jaw became stronger and the muscles are more powerful. This allows it to be a perfect killer. Its' teeth have adapted to be able to crush the thick shell of the crusher worm. The insectoid jaws develop ridges in order to slice through flesh. It can also eat corpses, if desperate. It can also crunch rocky capiri eggs with their strong jaws. To hunt larger or similarly sized creatures, they hunt in groups. With this advantage they can kill the cleaner sauceback, cunning lizardworm, and the young of brutish lizardworms. However, they don't eat just meat. Strongjaw lizardworms can also eat the vandriswoop, and sometimes the irontangle with it.
In physical changes, the strongjaw lizardworms' anterior legs become stronger, and the posterior legs are now only used to cling to each other during mating. Its' hind legs develop a lot of nerve-endings, so touching each other with these legs generate sexual excitement during copulation.
Artwork by OviraptorFan