Infection with the dinoflagellate parasite Blastodinium spp. in two Mediterranean copepods

Abstract

Infection with the intestinal parasite Blastodinium mangini resulted in reduced survival of starved adults of the Mediterranean copepod Oncaea sp. No such effect was measurable for Corycaeus sp. infected by Blastodinium navicula. Both sexes of Oncaea sp. adults were infected by B. mangini and infected copepods were able to mate successfully. However, Oncaea sp. females infected by B. mangini did not produce eggs and, thus, appeared to be sterile. By inducing sterility, the harmful effect of B. mangini infection on Oncaea sp. populations is bound to be more profound than the effect on the individual level. The mechanism of infection by Blastodinium spp. remains unknown, but uptake of parasite zoospores by Oncaea sp. copepodites concurs with the hypothesis that infection occurs through the ingestion of zoospores by juvenile hosts