Animal Taxonomy

The following is a list of the classes in each phylum of the kingdom Animalia. There are 108 classes of animals in 34 phyla in this list. However, different sources give different numbers of classes and phyla. For example, Protura, Diplura, and Collembola are often considered to be the three orders in the class Entognatha. This list should by no means be considered complete and authoritative and should be used carefully.

Aschelminthes

 * Acanthocephala
 * Chaetognatha
 * Cycliophora
 * Gastrotricha
 * Kinorhyncha
 * Loricifera
 * Nematoda
 * Nematomorpha
 * Priapulida
 * Rotifera

Acanthocephala

 * Archiacanthocephala
 * Eoacanthocephala
 * Palaeacanthocephala

Acoelomorpha

 * Acoela
 * Nemertodermatida

Annelida (segmented worms)

 * Aelosomata
 * Clitellata (earthworms)
 * Myzostomida
 * Polychaeta
 * Echiura

Chelicerata

 * Arachnida (spiders, scorpions, and kin)
 * Xiphosura (horseshoe crabs; only 4 extant species)
 * Pycnogonida (sea spiders)

Crustacea

 * Branchiopoda (fairy shrimp, tadpole shrimp, water fleas, and clam shrimp)
 * Cephalocarida (horseshoe shrimp; only 12 described species)
 * Malacostraca (crabs, lobsters, crayfish, krill, various shrimp, woodlice, and kin)
 * Maxillopoda (barnacles, copepods, fish lice, and other groups)
 * Ostracoda (seed shrimp)
 * Remipedia (no common name)

Hexapoda

 * Protura (coneheads)
 * Diplura (two-pronged bristletails)
 * Collembola (springtails)
 * Insecta (insects)

Myriapoda

 * Chilopoda (centipedes)
 * Diplopoda (millipedes)
 * Pauropoda (no common name)
 * Symphyla (pseudocentipedes)

Onychophora

 * Onychophorida

Tardigrada (tardigrades, water bears, or moss piglets)

 * Eutardigrada
 * Heterotardigrada

Brachiopoda

 * Craniforma
 * Lingulata
 * Rhynchonellata

Bryozoa

 * Gymnolaemata
 * Phylactolaemata
 * Stenolaemata

Chaetognatha

 * Archisagittoidea
 * Sagittoidea

Cephalochordata

 * Leptocardii (lancelet)

Tunicata

 * Appendicularia (larvaceans)
 * Ascidiacea (sea squirts)
 * Sorberacea (no common name)
 * Thaliacea (salps, pyrosomes, and doliolids)

Cyclostomata

 * Myxini (hagfish)
 * Petromyzontida (lamprey)

Gnathostomata

 * Chondrichthyes (cartilaginous fish, mostly sharks and rays)

Tetrapoda

 * Amphibia

Amniota

 * Mammalia (mammals)
 * Aves (birds)
 * Reptilia (reptiles)

Osteichthyes

 * Actinopterygii (ray-finned fish, which includes most familiar bony fish)
 * Sarcopterygii (lobe-finned fish)

Cnidaria (jellyfish, corals, anemones, and others)

 * Anthozoa (corals and anemones)
 * Cubozoa (box jellyfish)
 * Hydrozoa (hydroids and others)
 * Malacosporea
 * Myxosporea
 * Scyphozoa (true jellyfish)
 * Staurozoa (stalked jellyfish)
 * Polypodiozoa

Dicyemida

 * Dicyemida

Crinozoa

 * Crinoidea (sea lilies and feather stars)

Asterozoa

 * Asteroidea (star fish)
 * Ophiuroidea (brittle stars)

Echinozoa

 * Echinoidea (sea urchins)
 * Holothuroidea (sea cucumbers)

Entoprocta

 * Entoprocta

Gastrotricha

 * Gastrotricha

Gnathostomulida

 * Gnathostomulida

Hemichordata

 * Enteropneusta
 * Pterobranchia

Mollusca

 * Bivalvia (clams, mussels, scallops, and kin)
 * Caudofoveata
 * Cephalopoda (octopuses - see Octopus)
 * Gastropoda (snails and slugs)
 * Monoplacophora
 * Polyplacophora
 * Scaphopoda
 * Solenogastres

Nemertea

 * Anopla
 * Enopla

Orthonectida

 * Orthonectida

Phoronida

 * Phoronida

Placozoa

 * Trichoplacoidea

Platyhelminthes (flatworms)

 * Cestoda show characteristics of both cestodes and tremoteds
 * Monogenea
 * Trematoda flukes e.g. Clonorchis sinensis, Fasciola hepatica, schistosomes
 * Turbellaria e.g. Dugesia

Porifera (sponges)

 * Calcarea
 * Demospongiae
 * Hexactinellida

Xenoturbellida

 * Xenoturbellida