Lizardworm

The lizardworm branched off from the leatherback scuttlecrab after the scuttlecrab colonized the Irinya Islands. It feeds on its ancestral scuttlecrabs using its newly formed jaw. This feature is the result of the insectoid mandibles of the scuttlecrab fusing together and attaching to the fleshy real head inside of the pseudo-head, allowing them to move up and down rather than together and apart. The oral ring muscles of its original head serve to open and close the jaw, and the teeth of the oral ring are now anchored to the pseudo-head and mandible-jaw sclerites to increase their effectiveness. The pincers of the scuttlecrab became down turned and specialized for walking, while its first rear legs moved further towards the rear. The body lengthened and became more worm-like. They evolved a primitive endoskeleton in addition to their exoskeleton. Its second rear legs degenerated and became a pair of small spines halfway down and on each side of its tail. At some stage during its evolution, the lizardworm lost its symbiotic relationship with testudohexapodia spherus. The lizardworm is native to the Irinya Islands.