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                        Introduction                                                                                                                                                    Bryozoa


Invertebrate Zoology

Kingdom:  Animalia, Phylum: Gastritricha



Phylum:  Gastrotricha -- Hairy backs

    Class:  Macrodasyida
    Class:  Chaetonotida

Bibliography     Citations     Plates

Sample Examinations 

Invertebrate Classification


          The Phylum:  Gastrotricha are minute worm-like animals that are known as "Hairy Backs."  They are ciliated on the ventrum, which causes a gliding movement.  Their cuticle bears scales and bristles.  There is a forked tail with cement glands and a simple alimentary canal.  Flame cells are present.  There is a simple ganglion with a few branching nerves.  Reproduction has not been extensively studied, but most species are known to be hermaphroditic and some are parthenogenetic.  They are freshwater forms.


          Their shape is usually elongated and their movement is by means of their cilia or their musculature.



          Gastrotricha have features in common with Rotifera in their external ciliation, bifid foot and an excretory system with flame cells.  On the other hand, the character of their gut resembles the Nematoda.




Please see following plate for Example Structures of the Gastrotricha:


Plate 60 = Example Structure of Gastrotricha.






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