505 MYA lived a slight (0.5–3.5 cm) wormy creature with 7–8 pairs of legs that ended in claws, and long spikes the rose from its body. It was hard to tell the head from the tail. Hallucigenia clearly had features for defense against predators.
Caterpillars would later take this form, albeit distinctly. The descendants of Hallucigenia include arthropods and modern velvet worms.