Ambulacraria

Ambulacraria is a clade of invertebrate phyla which includes echinoderms and hemichordates; a member of this group is called an ambulacrarian. The Ambulacraria are part of the Deuterostomes, a larger clade that also includes the Chordata and Vetulicolia. The two living phyla with representative organisms are: Phylum Echinodermata (sea stars, sea urchins, brittle stars, sea cucumbers, feather stars, sea lilies, etc.) Phylum Hemichordata (acorn worms, Pterobranchia, and possibly graptolites) The phylum Xenoturbellida (two species of worm-like animals) has previously been considered to be in this clade, but is now considered to be placed more basally among Metazoans. Fossil taxa that may lie on the stem lineage: ?Superphylum Ambulacraria# unranked clade Cambroernida unranked clade = Eldoniida † Herpetogaster Caron, Conway Morris & Shu, 2010 – with one species: † Herpetogaster collinsi Caron, Conway Morris & Shu, 2010