Animal mesoderm forms by enterocoelic pouching, through invagination of the endoderm. The main deuterostome phyla are the Echinodermata and the Chordata. Echinoderms are exclusively marine and include starfish, sea urchins, and sea cucumbers. The chordates are dominated by the vertebrates (animals with backbones), which consist of fishes, amphibians, reptiles, birds, and mammals. The deuterostomes also include the Hemichordata (acorn worms). The Ecdysozoa are protostomes, named after their shared trait of ecdysis, growth by moulting. They include the largest animal phylum, the Arthropoda, which contains insects, spiders, crabs, and their kin. All of these have a body divided into repeating segments, typically
Bacterial phyla and NCBI lists 120 phyla, including 90 candidate phyla (AC1, Acetothermia, Aerophobetes, Aminicenantes, Atribacteria, Berkelbacteria, BRC1, CAB-I, Calescamantes, CPR1, CPR2, CPR3, EM 3, Fervidibacteria, GAL15, GN01, GN03, GN04, GN05, GN06, GN07, GN08, GN09, GN10, GN11, GN12, GN13, GN14, GN15, Gracilibacteria, Fermentibacteria (Hyd24-12), Hydrogenedentes, JL-ETNP-Z39, KD3-62, kpj58rc, KSA1, KSA2, KSB1, KSB2, KSB3, KSB4, Latescibacteria, marine group A, Marinimicrobia, Microgenomates, MSBL2, MSBL3, MSBL4, MSBL5, MSBL6, NC10, Nitrospinae, NPL-UPA2, NT-B4, Omnitrophica, OP2, OP4, OP6, OP7, OS-K, Parcubacteria, Peregrinibacteria, Poribacteria, RF3, Saccharibacteria, SAM, SBR1093, Sediment-1, Sediment-2, Sediment-3, Sediment-4, SPAM, SR1, TA06, TG2, TM6, VC2, WOR-1, WOR-3, WPS-1, WPS-2, WS1, WS2, WS4, WS5, WS6, WWE3,