Animal Kingdom Classification On Basis Of 11 Phyla

This resource is about the further classification of Animal Kingdom into 11 phyla based on their characters and their detailed explanation. This information is very useful as the details are helpful for the higher secondary studies of subject Zoology.

Earlier eras of human life seek answer for the question of classification. man began to classify organisms and other living things based
on their need.
The attempt for a scientific classification was first given by Aristotle. Today the most accepted classification is Five Kingdom Classification. It was prepared by R.H. Whittaker in 1969. He divided living things into five.
They were Kingdom Monera, kingdom Protista, Kingdom Fungi, Kingdom Plantae and finally the long Kingdom Animalia.
The number of organisms were high in Kingdom Animalia that a need of further classification of the Kingdom was essential. Thus Animal Kingdom was classified to 11 phyla based on some main features. that were ;

1. Level of Organization in animals

Animals were classified to 4 levels. They were ;

Cellular level of organization

Organisms like sponges belong to this category. There is only one Phylum under this category and that is Phylum Porifera. Their all functions are done by cells. most of the organisms of this group is multicellular organisms.

Tissue level of organization

Phylum Coelenterata and Phylum Ctenophora belong to this category.They have collection of cells called tissues for each function.

Organ level of organization

The tissues are added and organs are formed. Such special organisms are doing the functions.Phylum Platyhelminthes belong to this group.

Organ system level of organization

Organs are constituted to form Organ systems like circulatory system etc. The organisms include Phylum Aschhelminthes to chordata.

For convenience the 4 levels are concluded to 2 or three were tissue level, organ system level and organ level joined together

2. Symmetry classification

Animals are classified to three.


In this group organisms which cannot be cut into equal halves are added and only Phylum Porifera belongs to this group.

Radially symmetrical

The organisms which can be cut into equal halves if any line passing through centre is drawn are added in this group.Phylum Coelenterata (also called cnidaria) is and phylum ctenophora is added din this group.

Bilaterally symmetrical

Organisms which can be cut to equal halves only by median passing through centre are included. The organisms from Platyhelminthes to chordata include in this table.

3. Coelom structure

Coelom is the space between alimentary canal and skin. It varies in organisms.


The organisms with no coelom is added here.The only phylum here is Platyhelminthes. (flat worms).


They have coelom in the form of scattered pouches. Organisms of phylum Aschhelminthes , the round worms belong to this group.


They have well built coelom. Phylum Annelida to chordata belong to this group. We humans also belong to this group.

Other basis used are;
The rod like structure at dorsal (back side).

5. Segmentation.
The body of some may be divided to different segments . Example earthworm.

Now to the 11 phyla.

Phylum Porifera

The first classification of animals. Only sponges belong to this group. From the above features told the special features to sponges are things like marine life, water canal system, Internal fertilization and indirect development.(many larvae formed in development stages)
Examples for organisms in the group;
Euspongia (bath sponge - earlier used for bathing)
Spongilla ( one of the rare freshwater sponge)

Phylum Coelenterata

The distinguishing features of this group is the coelontrom body - cylindrical shape, CaCO3 skeleton, two types of body differentiation,Poison containing cnidoblasts at tentacles.(so also called cnidaria phylum)
The two bodies differ in organisms. Some have cylinder shaped polyp structure but some have umbrella shaped structure called Medusa.
Examples for organisms of Coelenterata group.
Aurelia(jelly fish) - Medusa structure
Adamsia (sea animon - polyp structure

Phylum Ctenophora

Exclusively marine form. Other features are comb plates (one pair) with hair like cilia for movement.Fertilization external and bioluminesencse (glowing organism) also. Special features are gifted for this group.
(many others also. unavailable to me)

Phylum Platyhelminthes

Flat worms are the members of the group. speciality is flame cells for excretion.
Taenia(tape worm)

Phylum Aschhelminthes

Organisms are round worms. speciality - male small and female long.Complete alimentary canal etc..
Ascaris (round worm)
Ancylostoma( hook worm)

Phylum Annelida

Speciality is metamerism or segmentation of body. Excretory organs like nephredia present in it. Also havelocomotory organs like parapodia or muscles. separate sexes are seen while some are moneocious (no female or male differentiation both in one.)

Phylum Arthropoda

The special feature is Jointed appendages(legs). have three parts for body. Head, Thorax, and Abdomen.It is the largest phylum. Highest number of organisms are seen in this group.
Apis(honey bee)
Bombyx(silk worm)

Phylum Mollusca

Have high number of organism and have second place. Shelled organisms are in this group. The visceral hump, Foot and head are main body parts.

Phylum Echinodermata

Water vascular system is the special feature. All are marine and have similarity to ctenophora phylum. Fertilization is external and sexes are separate.
Asterias(star fish)

Phylum Hemichordata

Worm like structure. Body parts are Proboscis, collar, and trunk. have cylindrical body.
Excretory organ is proboscis gland.

Phylum Chordata

Organisms with notochord , dorsal nerve chord and paired pharyngeal gill slits. They may be in embryonic stage.
Homo sapiens.

This resource is for the ones who love Zoology.


No responses found. Be the first to comment...

  • Do not include your name, "with regards" etc in the comment. Write detailed comment, relevant to the topic.
  • No HTML formatting and links to other web sites are allowed.
  • This is a strictly moderated site. Absolutely no spam allowed.
  • Name: