Phylum Chordata, Subphylum Vertebrata. Terragen animals that have a backbone, and usually an endoskeleton. The backbone consists of ring-like bones (vertebrae) that protect the soft spinal cord. Vertebrates evolved during the Cambrian period as jawless, toothless fish (agnatha). From these evolved jawed placoderms (extinct, but many species have been lazurogened), acanthodians (likewise known only from fossils or as lazurogens), sharks, bony fish, coelacanths, lungfish, and lobe-finned fish (including not only coelacanths and lungfish but also the fish that gave rise to the amphibians, reptiles, birds and mammals).
Vertebrate-like morphotypes have appeared a number of times in non-terragen ecosystems. Ratay's Vision (STC volume), Howabunga (MPA), Garri Garri (Metasoft), and Nemoy (Orion Federation), are among a number of garden worlds where vertebrate-like biota have evolved.