Fieldia is a genus of worm known from the Cambrian Burgess Shale, and assigned to the Priapulids.It was originally interpreted as an arthropod; its trunk bears a dense covering of spines, and its proboscis is small. It fed on sea-floor mud, evidenced by the frequent presence of sediments preserved in its gut. 18 specimens of Fieldia (animal) are known from the Greater Phyllopod bed, where they comprise 0.03% of the community.