Platytrochozoa
The Platytrochozoa are proposed basal clade of spiralian animals as sister group of the Gnathifera. The Platytrochozoa were divided into the Rouphozoa and the Lophotrochozoa. A more recent study suggests that the mesozoans also belong to this group of animals, as sister of the Rouphozoa.
An alternative phylogeny was given in 2019, with a basal grouping Mollusca with Entoprocta grouping named Tetraneuralia, and a second grouping of Nemertea with Platyhelminthes named Parenchymia as sister of Annelida. In their proposal, Lophotrochozoa would become roughly synonymous with Platytrochozoa, and Rouphozoa is unsupported.
