Kingdom Animalia Linnaeus, 1758 - animals
   Phylum Chordata Bateson, 1885 - chordates
     Subphylum Urochordata Bateson, 1885 - tunicates
       1 Class Ascidiacea Blainville, 1824 - sea squirts
       2 Class Thaliacea van der Haeven, 1850 - salps
       3 Class Appendicularia Lahille, 1890 - appendicularians
       4 Class Sorberacea C. Monniot et al., 1975