The phylum :Coelenterata
They are typically invertebrate aquatic animals, which show a very simple level tissue organisation. They are mostly found in marine environments, attached to the rocks at the bottom of the ocean. Some of species are also found in freshwater habitats. Coelenterates can be found solitarily or in colonies.
Organization Level : Tissue
Symmetry : Radial
Coelom : Absent
Respiratory system : Absent
Digestive system : Incomplete
Circulatory System : Absent
Classification of Coelenterata
Anthozoa | Hydrozoa | Scyphozoa |
---|---|---|
Exclusively in the marine environment. Mesogloea contains fibrous connective tissues and amoeboid cells. Medusa is not present. | These are mostly marine species, exclusively in freshwater. Few are found in colonies and solitarily. Asexual Polyps is the dominant form. Mesogloea is acellular. | Exclusively in the marine environment. Medusa is dominant and umbrella-shaped. Polyps are not present. Mesogloea is cellular. |
Metridium, Xenia | Hydra, Obelia | Aurelia aurita, Rhizostoma |