Marine Biology

, Volume 81, Issue 1, pp 9–17

The role of chemosensory behavior of Symbiodinium microadriaticum, intermediate hosts, and host behavior in the infection of coelenterates and molluscs with zooxanthellae

  • W. K. Fitt

DOI: 10.1007/BF00397620

Cite this article as:
Fitt, W.K. Mar. Biol. (1984) 81: 9. doi:10.1007/BF00397620


Symbiotic dinoflagellates, Symbiodinium microadriaticum (=zooxanthellae), may gain access to aposymbiotic hosts (i.e., those lacking zooxanthellae) by chemosensory attraction of the motile algae by the potential host or via an “intermediate” host. Laboratory experiments showed that motile zooxanthellae were attracted to intact aposymbiotic host animals, but not to starved symbiotic hosts. Fed symbiotic hosts and brine shrimp (Artemia sp.) nauplii also attracted motile zooxanthellae. The attraction of these zooxanthellae was directly correlated with nitrogen levels in the seawater surrounding the hosts; thus ammonia and possibly nitrate could be atractants. Brine shrimp nauplii, acting as “intermediate” hosts actively ingested both motile and non-motile zooxanthellae. the ingested zooxanthellae tended to remain morphologically unaltered during and after passage through the gut of the brine shrimp. Capture and ingestion of brine shrimp containing zooxanthellae by aposymbiotic scyphistomae of the jellyfish Cassiopeia xamachana led to infection of the scyphistomae with zooxanthellae. Zooxanthellae isolated from 17 different species of coelenterates and molluscs could be transferred via brine shrimp to the endodermal cells of the scyphistomae. However only 10 of these isolates persisted to establish a permanent association with C. xamachana. Scyphistomae in suspensions of motile zooxanthellae responded by a classical coelenterate feeding response, which may facilitate ingestion of the potential symbionts and establishment of a symbiosis.

Copyright information

© Springer-verlag 1984

Authors and Affiliations

  • W. K. Fitt
    • 1
    • 2
  1. 1.Department of Biological SciencesUniversity of California at Santa BarbaraSanta BarbaraUSA
  2. 2.Marine Science InstituteUniversity of California at Santa BarbaraSanta BarbaraUSA
  3. 3.Lehrstuhl für Spezielle ZoologieRuhr-Universität BochumBochum 1Germany (FRG)