List of animal classes
The following is a list of the classes in each phylum of the kingdom Animalia. There are 107 classes of animals in 33 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.
Unknown phylum">Incertae sedis">Unknown phylum
- Micrognathozoa
[Acanthocephala] (thorny-headed worms)
- Archiacanthocephala
- Eoacanthocephala
- Palaeacanthocephala
[Acoelomorpha] (simple soft-bodied flatworms)
- Acoela
- Nemertodermatida
[Annelida] (segmented worms)
- Aelosomata
- Clitellata
- Myzostomida
- Polychaeta
- Echiura
- Sipuncula
[Arthropoda] (arthropods: insects, crustaceans, arachnids, centipedes, and millipedes)
[Chelicerata]
- Arachnida
- Xiphosura
- Pycnogonida
Crustacea">Crustacean">Crustacea
- Branchiopoda
- Cephalocarida
- Malacostraca f
- Maxillopoda
- Ostracoda
- Remipedia
[Hexapoda]
- Entognatha
- Insecta
[Myriapoda]
- Chilopoda
- Diplopoda
- Pauropoda
- Symphyla
[Brachiopoda] ("lamp shells")
- Craniforma
- Rhynchonellata
[Bryozoa] (moss animals)
- Gymnolaemata
- Phylactolaemata
- Stenolaemata
[Chaetognatha] (arrow worms)
- Archisagittoidea
- Sagittoidea
Chordata">Chordate">Chordata (vertebrates, tunicates, and lancelets)
[Cephalochordata]
- Leptocardii
[Tunicata]
- Appendicularia
- Ascidiacea
- Sorberacea
- Thaliacea
[Vertebrata]
[Agnatha]
[Cyclostomata]
- Myxini
- Petromyzontida
[Gnathostomata]
- Chondrichthyes
[Osteichthyes]
- Actinopterygii
- Sarcopterygii
[Tetrapoda]
- Amphibia
- Amniota
- * Mammalia
- * Aves
- * Reptilia
[Cnidaria] (marine stinging animals)
- Anthozoa
- Cubozoa
- Hydrozoa
- Malacosporea
- Myxosporea
- Scyphozoa
- Staurozoa
- Polypodiozoa
[Cycliophora] (tiny marine animals)
- Eucycliophora
[Dicyemida] (rhombozoa)
- Dicyemida
[Echinodermata] (starfish, sea urchins, sand dollars, sea lilies, and others)
[Crinozoa]
- Crinoidea
[Asterozoa]
- Asteroidea
- Ophiuroidea
[Echinozoa]
- Echinoidea
- Holothuroidea
[Entoprocta]
- Entoprocta
[Gastrotricha] (hairybacks)
- Gastrotricha
[Gnathostomulida] (jaw worms)
- Gnathostomulida
[Hemichordata]
- Enteropneusta
- Pterobranchia
[Kinorhyncha] (mud dragons)
- Kinorhyncha
[Loricifera]
- Loricifera
[Mollusca] (mollusks)
- Bivalvia
- Caudofoveata
- Cephalopoda
- Gastropoda
- Monoplacophora
- Polyplacophora
- Scaphopoda
- Solenogastres
[Nematoda] (roundworms)
- Adenophorea
- Chromadorea
- Secernentea
[Nematomorpha] (horsehair worms)
- Gordioidea
- Nectonematoida
[Nemertea] (ribbon worms)
- Anopla
- Enopla
[Onychophora] (velvet worms)
- Udeonychophora
[Orthonectida]
- Orthonectida
[Placozoa]
- Trichoplacoidea
[Platyhelminthes] (flatworms)
- Cestoda
- Monogenea
- Trematoda
- Turbellaria
[Porifera] (sponges)
- Calcarea
- Demospongiae
- Hexactinellida
- Homoscleromorpha
[Priapulida] (priapulid worms)
- Halicryptomorpha
- Priapulimorpha
- Seticoronaria
[Rotifera] (rotifers)
- Bdelloidea
- Monogononta
- Seisonidea
[Tardigrada] (tardigrades, water bears, or moss piglets)
- Eutardigrada
- Heterotardigrada
[Xenoturbellida]
- Xenoturbellida