Clade Xenacoelomorpha Philippe et al. 2011
Full reference: H. Philippe, H. Brinkmann, R. R. Copley, L. L. Moroz, H. Nakano, A. J. Poustka, A. Wallberg, K. J. Peterson, and M. J. Telford. 2011. Acoelomorph flatworms are deuterostomes related to Xenoturbella. Nature 470:255-260
Parent taxon: Deuterostomia according to H. Philippe et al. 2011
Sister taxa: Ambulacraria, Chordata, Saccorhytida
Subtaxa: Acoelomorpha