Archaeopriapulida

The archaeopriapulida are a group of priapulid-like worms known from Cambrian lagerstatte. The group was originally assumed to be a clade, ancestral but very similar to the modern Priapulids. It includes the genera Ottoia, Selkirkia, Louisella, Ancalagon, Scolecofurca, and Lecythioscopa. The morphological similarity of these organisms to their modern cousins is remarkable, especially for the Burgess Shale. A phylogenetic analysis does not provide a great deal of resolution to the relationships between these basal worms.