are a group of animals
united by the presence of a lophophore, a fan of cilia surrounding the mouth. They include three phyla - the Brachiopoda
, and Phoronida
- and possibly a fourth, the Entoprocta
. The oldest forms are known from the early Cambrian
. The exact placement of the lophophorates and even their monophyly remain uncertain. They are sometimes ranked as a superphylum or phylum Lophophorata.