The Kingdom Animalia is currently divided into 32 phyla (singular phylum). Catalogue of Life
Generally speaking, people consider the animals of this world to be divided into two groups, the ‘vertebrates’ (those with backbones) and the ‘invertebrates’ (those without backbones).
Although this is correct, as far as it goes – it does not give a accurate picture of the importance of the two groups, nor of their relative sizes and complexities.
The invertebrates make up easily more than 99% of all recorded animal species and in terms of individuals would account for more than 99.99% of all animals.
Invertebrates are members of the Kingdom Animalia. They are linked together by the fact that they have no backbone or vertebrae. They do not include the Protozoa, who are generally considered to be part of the Kingdom Protista.
The diversity and number of invertebrates is mind boggling. Most of them however, are insects.
Below is a list of the animal phyla with their common name and approximate number of named species. You can follow the links to a page about each phyla. In order to make certain that something is available concerning each phyla quickly, I have written a brief introduction to each for the time being.
Table of the Phyla of Kingdom Animalia
| Scientific Name (Phylum) | Common Name | No. Species |
|---|---|---|
| Acanthocephala | Spiny-headed Worms | 1000 |
| Annelida | Earthworms, Ragworms | 9000 |
| Arthropoda | Insects, Crabs, Spiders etc. | 1000000 |
| Brachiopoda | Lamp Shells | 335 |
| Bryozoa | Bryozoans | 5000 |
| Cephalorhyncha | Tiny Marine Worms:- Includes Kinorhyncha, Loricifera and Priapulida | 237 |
| Chaetognatha | Arrow-worms | 110 |
| Chordata | Chordates (Tunicates, Mammals, Birds etc.) | 50000 |
| Cnidaria | Sea Anenomes, Jellyfishes | 9500 |
| Ctenophora | Comb Jellies | 90 |
| Cycliophora | Cycliophorans | 1 |
| Dicyemida | Tiny Marine Parasites of Octopus and Squids | 122 |
| Echinodermata | Starfish and allies | 6 000 |
| Entoprocta | Goblet Worms | 150 |
| Gastrotricha | Gastrotrichs | 400 |
| Gnathostomulida | Sand Worms | 80 |
| Hemichordata | Hemichordates | 90 |
| Micrognathozoa | Tiny Freshwater Worms | 1 |
| Mollusca | Slugs, Snails, Squid. | 110000 |
| Nematoda | Nematodes | 25,000 named, many more un-named |
| Nematomorpha | Horsehair Worms | 240 |
| Nemertea | Ribbon Worms | 900 |
| Onychophora | Peripatus | 80 |
| Orthonectida | Tiny Parasites of Starfish, Bivalves and Worms | 25 |
| Phoronida | Phoronans | 10 |
| Placozoa | Placozoa | 3 |
| Platyhelminthes | Flat Worms | 25000 |
| Porifera | Sponges | 10000 |
| Rotifera | Rotifers | 2000 |
| Sipuncula | Peanut Worms | 320 |
| Tardigrada | Water Bears | 700 |
| Xenacoelomorpha | Microscopic Marine Worms | 456 |
Some Recent Changes
The Pentastomida are now part of the Arthropoda; Crustacea, Maxillopoda
The Echiura, and Pogonophora are now part of the Annelida.
The Kinorhynca, Loricifera and Priapulida are now all together in the Cephalorhyncha
The Mesozoa has been now split into Orthonectida and Dicyemida
The phylum Xenocoelomorpha was created
The Myxozoa, which were briefly raised to the level of phylum are now firmly located in the phylum Cnidaria
The list above represents just one of several taxonomic classifications of the Kingdom Animalia and it is one which I find useful.
I have listed the animal Phyla here alphabetically, so as to facilitate people finding a particular phyla. As such the listing does not reflect any evolutionary or phylogenetic relationships between the individual phyla. I’ve also given an approximate value for the number of species it contains; these values represent minimum values. It is worth remembering that there are an unknown number of undiscovered species in every phyla.
Very cool site. I found you looking for info on a Bio Lab for my college class. Great work. You have made it very easy to understand and the site is well laid out. Great work!