C N I D E R I A N S

 

Cnidarians (coming from the Greek CNIDOS= stinging needle) are incredibly diverse in form but come in two fundamental shapes, polypoid and medusoid shapes. The main characteristic feature is the presence tentacles set in a radial symmetry with their digestive system in the middle. On these tentacles are found the nematocysts (stinging cells that can be ejected at a prey if they come close enough) used to subdue and capture food by the use of a toxin, that can be sometimes even lethal to man. Cnidarians can be found as single element or in colonies (like coral)

 
There are 9000 species (400 in the Mediterranean) of cnidarians organized in four major groups: Anthozoa, which includes true corals, anemones, and sea pens; Cubozoa, the amazing box jellies with complex eyes and potent toxins; Hydrozoa, the most diverse group with siphonophores, hydroids, fire corals, and many medusae; and Scyphozoa, the true jellyfish.
 
Anthozoa:

Asteroides Clycularis

Calliactis Parasitica

Alicia Mirabilis

Condy Lactis Aurantiaca

 

Scyphozoa (jelly Fish)

Aurelia Aurita

Rhizostoma Pulmo

 

Hydrozoa :

Velella Vellella

 


COTHYLORIZA TUBERCULATA - CASSIOPEIA - FRIED EGG JELLY FISH

   
 
Belongs to the Order Rhizostomae. Family Cepheidae. One of the most common jellyfish in the Mediterranean sea and definitely the most colorful of all. The animal can grow to 35 cm in diameter and in contrast to most jellyfishes has an ability to move on its own. It migrates vertically while various juvenile fishes are associated with it.

This species feeds on Microplankton and has separate sexes. The eggs are fertilized internally, the larvae kept in pockets and then are released in the open water where they developed into sessile polyps.
 

 

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