| Phylum Porifera (esponjas) | Phylum Entoprocta |
| Phylum Cnidaria (medusas, corales, anémonas) | Phylum Cycliophora |
| Phylum Ctenophora | Phylum Mollusca (caracoles, almejas, pulpos, etc.) |
| Phylum Placozoa | Phylum Pogonophora |
| Phylum Myxosporidia | Phylum Echiura |
| Phylum Platyhelminthes (planarias, fasciolas, tenias) | Phylum Sipuncula (sipuncúlidos) |
| Phylum Gastrotricha | Phylum Annelida (lombrices de tierra, gusanas, sanguijuelas) |
| Phylum Gnathostomulida | Phylum Arthropoda (insectos, cangrejos, arañas, garrapatas, ciempiés, etc.) |
| Phylum Nemertea | Phylum Tardigrada |
| Phylum Mesozoa | Phylum Bryozoa |
| Phylum Rotifera (rotíferos) | Phylum Brachiopoda |
| Phylum Nematoda | Phylum Phoronida |
| Phylum Nematomorpha | Phylum Chaetognatha |
| Phylum Kinorhyncha | Phylum Echinodermata (erizos de mar, estrellas de mar) |
| Phylum Acanthocephala | Phylum Hemichordata |
| Phylum Priapula | Phylum Urochorda (ascidias, salpas, larváceos) |
| Phylum Chordata (anfioxos, lampreas, peces, anfibios, reptiles, aves, mamíferos) |