Pfiesteria shumwayae
Pfiesteria shumwayae
Pfiesteria shumwayae or Pseudopfiesteria shumwayae is a heterotrophic dinoflagellate of the genus Pfiesteria and was described in 2000 for the first time. The species can gain the ability to photosynthesize by eating autotrophic algae, with their chloroplasts are obtained as Kleptoplastide and used further. P. shumwayae but can also feed predatory, and toxic strains of P. shumwayae be associated with fish kills along the east coast of the United States. In contrast to the closely related species Pfiesteria piscicida has P. shumwayae a less complex life cycle. The species was named after Sandra E. Shumway, founder of the journal Harmful Algae.
Toxicity
Although toxic strains of Pfiesteria shumwayae be held responsible for fish kills, the ability to deliver toxins has been controversial. A 2002 published study found that P. shumwayae fish kills not by poison but by direct contact through Mikropredation. The protozoa feed on individual skin cells by Myzozytose, the fish dies on the sum of the smallest wounds. The detectability of poison seems to depend on the trunks and analytical methods used. Produced by a toxic strain venom can cause neural damage in rats.
Dissemination
Pfiesteria has a worldwide distribution and is typically found in estuaries and coastal waters. The organisms are harmless, as long as they do not occur en masse as algal blooms, because only in high concentrations, the protozoa are harmful by their Mikropredation and poison production. Mass occurrence of P. shumwayae for example, were observed in Taskinas Creek, a tributary of the York River in Virginia in March 2005.