Lateral reconstruction of the onychophoran, Aysheaia pedunculata, from the Middle Cambrian Burgess Shale of British Columbia. This marine lobopod is thought to be related to modern-day velvet worms, like Peripatus, which live in the moist leaf litter of tropical forests in South America. Aysheaia is often preserved in association with sponges on which it may have fed. The length of preserved fossils ranges from 1 to 6 cm.