Quantitative PCR assay for detection and enumeration of ciguatera-causing dinoflagellate Gambierdiscus spp. (Gonyaulacales) in coastal areas of Japan.

In Japan, ciguatera fish poisoning (CFP) has been increasingly reported not only in subtropical areas but also in temperate areas in recent years, causing a serious threat to human health. Ciguatera fish poisoning is caused by the consumption of fish that have accumulated toxins produced by an epiphytic/benthic dinoflagellate, genus Gambierdiscus. Previous studies revealed the existence of five Gambierdiscus species/phylotypes in Japan: Gambierdiscus australes, Gambierdiscus scabrosus, Gambierdiscus sp.

Morphology of Gambierdiscus scabrosus sp. nov. (Gonyaulacales): a new epiphytic toxic dinoflagellate from coastal areas of Japan.

A new epiphytic dinoflagellate is described, G ambierdiscus scabrosus sp. nov., from tidal pools and rocky shores along the coastal areas of Japan.

Genetic diversity and distribution of the ciguatera-causing dinoflagellate Gambierdiscus spp. (Dinophyceae) in coastal areas of Japan.

Background: The marine epiphytic dinoflagellate genus Gambierdiscus produce toxins that cause ciguatera fish poisoning (CFP): one of the most significant seafood-borne illnesses associated with fish consumption worldwide. So far, occurrences of CFP incidents in Japan have been mainly reported in subtropical areas. A previous phylogeographic study of Japanese Gambierdiscus revealed the existence of two distinct phylotypes: Gambierdiscus sp.

Quantitative PCR method for enumeration of cells of cryptic species of the toxic marine dinoflagellate Ostreopsis spp. in coastal waters of Japan.

Monitoring of harmful algal bloom (HAB) species in coastal waters is important for assessment of environmental impacts associated with HABs. Co-occurrence of multiple cryptic species such as toxic dinoflagellate Ostreopsis species make reliable microscopic identification difficult, so the employment of molecular tools is often necessary. Here we developed new qPCR method by which cells of cryptic species can be enumerated based on actual gene number of target species.

Phylogeography of ostreopsis along west Pacific coast, with special reference to a novel clade from Japan.

Background: A dinoflagellate genus Ostreopsis is known as a potential producer of Palytoxin derivatives. Palytoxin is the most potent non-proteinaceous compound reported so far. There has been a growing number of reports on palytoxin-like poisonings in southern areas of Japan; however, the distribution of Ostreopsis has not been investigated so far.