Infestation of the hard clam, Mercenaria mercenaria by the boring polychaete worm, Polydora ciliata
Landers, W.S. (1967). Infestation of the hard clam, Mercenaria mercenaria by the boring polychaete worm, Polydora ciliata. Proceedings of the National Shellfisheries Association 57: 63-66
In: Proceedings of the National Shellfisheries Association. Economy Printing: Easton. ISSN 0077-5711, more
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| Abstract |
Accidental and experimental infestation of the hard clam, Mercenaria mercenaria, by the polychaete worm, Polydora ciliata, in the laboratory is described. Experimental infestation was obtained by putting free-swimming larvae of P. ciliata in pans with hard clams; here the larvae metamorphosed and built tubes on the clams' shells. Perforation of the shells of clams 5-8 mm long appeared within IS days but took twice as long in clams 30-35 mm long. Calcified mud blisters appeared on the inner surfaces of the shells of all clams within 30 days after the shells were perforated. Despite considerable damage to the shells of the victims, especially small individuals, chi-square analysis of several groups of data did not consistently show statistical! y significant differences between the mortality of infested clams and controls. Clams in a sand substrate were not attacked by the worms. Several clams that became infested before they burrowed into the sand showed no signs of the worms when examined weeks later. It seems that, by burying, clams escape attack by P. ciliata but exposed clams, especially small ones, can suffer considerable damage to their shells. |
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