Anatomy & Physiology
The anatomical structure of a sponge is dependent on the sponge’s size. This determines its complexity of body forms ranging from asconoid, syconoid or leuconoid body forms (smallest to largest). Most sponges in the class Demospongiae have a Leuconoid body form, including Cliona.
Characersistics of this Leuconoid body design that are present in Cliona include:
o A complex system of branching canals, branched throughout the body, pumping water via incurrent and excurrent canals. In Cliona, the aquiferous system is also used to expel CaCO3 fragments taken from the substrate during the boring process and out of the body and back into the surrounding water.
o Formed as little circles, lining the excurrent and incurrent canals. Occur in high densities due to large size of body therefore need increase water flow which choanocytes chambers provide via beating flagella (tail on end of choanocyte that creates water flow by moving).
o Usually more present compared to sponges with syconoid and asconoid body forms.
o Not a syncytium (cytoplasm containing many nuclei that have not been divided) unlike other sponges. Primary cell type found in the epitheliod layer (outer surface) is the pinacocyte (see "Cell Types" for explanation).
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