Marine Biology

, Volume 55, Issue 4, pp 317–326 | Cite as

Stylochus mediterraneus (Turbellaria: Polycladida), predator on the mussel Mytilus galloprovincialis

  • L. Galleni
  • P. Tongiorgi
  • E. Ferrero
  • U. Salghetti


The polyclad Stylochus mediterraneus Galleni has been found associated with the mussel Mytilus galloprovincialis Lmk., on which it feeds. Polyclads allowed to feed freely on groups of mussels of different sizes preyed mainly on small mussels <25 mm in length. The predation rate (number of mussels eaten per no. of polyclads per no. of days) ranged between 0.07 and 0.33. The average amount of food ingested by 1 polyclad feeding on mussels 16 to 25 mm or 26 to 35 mm in length was 7.1 and 11.2 (dry weight) mg per day, respectively. Before penetrating the mussels, the worm first straddles the valves at the posterior edge of the shell and then, after having digested the posterior adductor muscle, removes and swallows the soft parts of the prey.


Adductor Muscle Average Amount Predation Rate Soft Part Posterior Edge 
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Copyright information

© Springer-Verlag 1980

Authors and Affiliations

  • L. Galleni
    • 1
  • P. Tongiorgi
    • 2
  • E. Ferrero
    • 3
  • U. Salghetti
    • 2
  1. 1.Istituto di Zoologia e Anatomia Comparata dell'Università di PisaPisaItaly
  2. 2.Istituto di Zoologia dell'Università di ModenaModenaItaly
  3. 3.Istituto di Zoologia e Anatomia Comparata dell'Università di TriesteTriesteItaly

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