Class Demospongiae: Most sponges belong in this class. this class includes sponges with a skeleton made up of silicon-containing spicules or spongin fibers. These sponges vary in size and shape. These sponges are the sponges that are most commonly used in kitchens.
The freshwater sponges (family Spongillidae) belong to this class; they are frequently green because of symbiotic algae that live in the amoebocytes. They prey on smaller organisms as well.
The fibrous sponges also belong to this class; they include the common bath sponges, Hippospongia communis and Spongia officinalis, and most of the other sponges used commercially.
Class Hexactinellida: These sponges are the deep sea sponges. They lack an epidermal covering, and their skeletons are composed of spicules of silica. a common deep sea sponge are the glass sponges. Glass sponges are pale in color and are cup- or basket-shaped.
Glass Sponges: They live in the antarctic ocean and eat smaller organisms.
Class Calcarea: Calcareous sponges take a wide range of shapes, including irregular massive forms. A common feature is the supporting skeleton, made of spicules. They can reproduce both sexually, and asexually.
Clathrina heronensis: A sponge that lives in the ocean and eats smaller organisms such as zoo plankton.
Leucetta chagosensis: This sponge eats the particles in the water, and lives in the ocean.