Portland State University. Department of Biology
Date of Award
Master of Science (M.S.) in Biology
1 online resource (65 p.)
Halosydna brevisetosa, Thelepus crispus
Chemical, physical and physiological interactions between the marine commensal scaleworm Halosydna brevisetosa Kinberg and its terebellid host, Thelepus crispus Johnson were investigated. In an experiment designed to test for chemical attraction between the host and commensal, Halosydna were unable to identify the arm in a U-tube choice apparatus leading to the host. In 50 trials, 54% of the commensals crawled into the flow of water from their hosts. Other observations showed that Halosydna made contact with the host by random encounter. After contact, commensals followed tentacles down into the host’s tube and took up a characteristic position along the dorsum of the host’s body wall. Halosydna’s specific orientation in the host’s tube may be the result of the current produced by the host rather than the presence of the host itself. Experiments with free-living forms of Halosydna revealed that these animals, not found in a commensal association, did not react to host tentacles, or to sea water containing several hosts.
The general purpose of this study was to investigate the commensal relationship between the polynoid Halosydna brevisetosa Kinberg and its terebellid host Thelepus crispus Johnson.
Morgan, John B., "Physiological and Behavior Studies of Thelepus Crispus and its Commensal Halosydna Brevisetosa" (1974). Dissertations and Theses. Paper 2010.