Send to

Choose Destination
J Eukaryot Microbiol. 2019 Jul;66(4):574-581. doi: 10.1111/jeu.12701. Epub 2018 Dec 11.

Phylogeny, Evidence for a Cryptic Plastid, and Distribution of Chytriodinium Parasites (Dinophyceae) Infecting Copepods.

Author information

Department of Botany, University of British Columbia, 3529-6270 University Boulevard, Vancouver, BC, V6T 1Z4, Canada.
Biosciences, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter, EX, 44QD, United Kingdom.
Monterey Bay Aquarium Research Institute, 7700 Sandholdt Road, Moss Landing, California, 95039.
Department of Ecology, Evolution and Marine Biology, University of California, Santa Barbara, California, 93106.


Spores of the dinoflagellate Chytriodinium are known to infest copepod eggs causing their lethality. Despite the potential to control the population of such an ecologically important host, knowledge about Chytriodinium parasites is limited: we know little about phylogeny, parasitism, abundance, or geographical distribution. We carried out genome sequence surveys on four manually isolated sporocytes from the same sporangium, which seemed to be attached to a copepod nauplius, to analyze the phylogenetic position of Chytriodinium based on SSU and concatenated SSU/LSU rRNA gene sequences, and also characterize two genes related to the plastidial heme pathway, hemL and hemY. The results suggest the presence of a cryptic plastid in Chytriodinium and a photosynthetic ancestral state of the parasitic Chytriodinium/Dissodinium clade. Finally, by mapping Tara Oceans V9 SSU amplicon data to the recovered SSU rRNA gene sequences from the sporocytes, we show that globally, Chytriodinium parasites are most abundant within the pico/nano- and mesoplankton of the surface ocean and almost absent within microplankton, a distribution indicating that they generally exist either as free-living spores or host-associated sporangia.


Gymnodinium ; Dinoflagellates; heme pathway; plankton; protists


Supplemental Content

Full text links

Icon for Wiley
Loading ...
Support Center