Marine Biology

, Volume 151, Issue 4, pp 1215–1223 | Cite as

Three party symbiosis: acoelomorph worms, corals and unicellular algal symbionts in Eilat (Red Sea)

  • O. Barneah
  • I. Brickner
  • M. Hooge
  • V. M. Weis
  • T. C. LaJeunesse
  • Y. BenayahuEmail author
Research Article


Epizoic worms were found to occur on certain coral colonies from reefs off the coast of Eilat (Red Sea). We identified 14 coral species infested by acoelomorph worms at a depth range of 2–50 m. The host corals were all zooxanthellate and included both massive and branching stony corals and a soft coral. Worms from all hosts were identified as belonging to the genus Waminoa and contained two distinct algal symbionts differing in size. The smaller one was identified as Symbiodinium sp. and the larger one is presumed to belong to the genus Amphidinium. Worm-infested colonies of the soft coral, Stereonephthya cundabiluensis, lacked a mucus layer and exhibited distinct cell microvilli, a phenotype not present in colonies lacking Waminoa sp. In most cases, both cnidarian and Acoelomorph hosts displayed high specificity for genetically distinctive Symbiodinium spp. These observations show that the epizoic worms do not acquire their symbionts from the “host” coral.


Trench Dinoflagellate Coral Species Soft Coral Coral Host 
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We are grateful to M. Ironi for valuable assistance in the laboratory and in the field, Y. Delaria for the electron microscopy, A. Shoob for photography, V. Wexsler for graphic assistance and N. Paz for editorial assistance. This research was in part supported by Grant 1998458 from the United State–Israel Binational Science Foundation (BSF), Jerusalem, Israel and by a grant from the Basic Research Fund of Tel Aviv University. Work on Symbiodinium genetics was supported by the NSF (Grant OCE-0137007) and conducted partly in the laboratory of Gregory W. Schmidt. O.B. was supported by a fellowship granted by Tobias Landau Foundation and Rieger JNF Fellow in Environmental Studies. We thank the staff of the Interuniversity Institute of Eilat for their kind hospitality and facilities.


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Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  • O. Barneah
    • 1
  • I. Brickner
    • 1
  • M. Hooge
    • 2
  • V. M. Weis
    • 3
  • T. C. LaJeunesse
    • 4
  • Y. Benayahu
    • 1
    Email author
  1. 1.Department of Zoology, George S. Wise Faculty of Life SciencesTel Aviv UniversityTel AvivIsrael
  2. 2.Department of Biological SciencesThe University of MaineOronoUSA
  3. 3.Department of ZoologyOregon State UniversityCorvallisUSA
  4. 4.Department of Biology, Marine Biology ProgramFlorida International UniversityMiamiUSA

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