Marine Biodiversity


Porifera (sponges)


Cnidaria (jellyfish, sea anemones, sea fans, soft corals, hard corals)


Ctenophora (comb-jellies)






Crustacea (crabs, lobsters, barnacles, isopods, amphipods) 


Annelida (segmented worms) 




Marine worms living in tubes. Some giant species, 1.5 m long have been found around warm water vents in the Pacific Ocean.





Echiura (spoon worms and innkeepers)

Once placed with the phylum Annelida.


Mollusca (snails, mussels, squid, etc.)


Sipuncula (peanut worms)



Nemertea (ribbon worms)

Marine worms that in some species can reach 30 m in length! Synonyms: Nemertini or Nemertina.


Platyhelminthes (flatworms, tapeworms) 




Marine organisms such as acorn worms.


Brachiopoda (lamp shells)

Look superficially like clams in that they have a similar shaped shell but they are not molluscs.


Ectoprocta (bryozoans or moss animals)

Found on rocky shores.





Chaetognatha (arrowworms)

About 70 species known.


Tunicata or Urochordata (tunicates, sea squirts, doliolids, salps)

Echinodermata (starfish, sea urchins, sea cucumbers, etc.) 


See the articles by Bevan Pank, many of which concern marine life.


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