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Updated: Jun 24, 2026

Cultivation of the Marine Pelagic Tunicate Dolioletta gegenbauri (Uljanin 1884) for Experimental Studies

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Speciation and symbiotic dinoflagellates.

R J Blank, R K Trench

Science (New York, N.Y.)

|August 16, 1985

Summary

Chromosomes in symbiotic dinoflagellates Symbiodinium microadriaticum show significant variations in number and volume. These differences suggest distinct species rather than variations within a single species.

Area of Science:

Marine biology
Microbiology
Genetics

Background:

Symbiodinium microadriaticum is a symbiotic dinoflagellate crucial for coral reef health.
These algae form vital partnerships with marine invertebrates like corals and giant clams.
Understanding Symbiodinium diversity is key to marine ecosystem research.

Purpose of the Study:

To investigate the nuclear morphology of different Symbiodinium microadriaticum strains.
To determine if observed variations represent different species or ploidy levels.
To contribute to the taxonomic clarification of Symbiodinium.

Main Methods:

Three-dimensional reconstruction of algal nuclei.
Detailed morphometric analysis of chromosome number and volume.

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Comparative analysis across four distinct Symbiodinium strains.

Main Results:

Significant differences in chromosome number were observed among the strains.
Marked variations in chromosome volume were identified.
The observed nuclear differences were inconsistent with varying ploidy states.

Conclusions:

The morphometric data strongly suggest that the analyzed strains represent distinct species.
This finding has implications for the taxonomy and understanding of Symbiodinium diversity.
Further research is warranted to confirm species status and explore ecological roles.