Author: Jan Scholten
Taxonomy: proposed by Thomas Cavalier-Smith in 1998. He included in Platyzoa the phylum Platyhelminthes ( flatworms), and a new phylum, the Acanthognatha, several phyla of microscopic animals. More recently it has been described as the Rouphozoa and the Gnathifera.
Zoology: small, flat, unsegmented animals; protostome; no respiration system; no circulation system; flat body or parasitic lifestyle.
Rouphozoa, Platyhelminthes and Gastrotricha, are acoelomate.
Gnathifera: have a pseudocoel; characteristic structure of their jaws and pharynx.
Rotifera, no flat, round