|Diversity of planulozoans|
Wallberg et al., 2004
Planulozoa is a proposed basal ParaHoxozoa clade, sometimes as sister of the Placozoa, but originally included Placozoa. In the latter case Planulozoa may be a senior synonym to Parahoxozoa. It contains the Cnidaria (sea anemones and jellyfish) and the Bilateria (all the more complex animals including flatworms, insects and vertebrates). The Placozoa may be a sister of Cnidaria or more conventionally of Planulozoa. The clade excludes basal animals such as the Ctenophora (comb jellies), and Porifera (sponges).
The phylogenetic tree indicates approximately how many millions of years ago (mya) the lineages split. Here, Planulozoa is shown sans Placozoa.
Planulozoa are associated with the emerge of the Zoc and ZF-NC gene domains.