The presence of toxic dinoflagellate Amphidinium sp. (Myzozoa) in the coastal waters of Sea of Oman

In this study, the morphological identification of Amphidinium (dinoflagellate) and its presence as a species with the potential to cause harmful algal blooms on the coast of Chabahar has been investigated. the Amphidinium was observed simultaneously with the blooming of Noctiluca scintillans in the coastal waters of Chabahar Bay 2020 located in the northern part of Sea of Oma in the february. Sampling of seawater was carried out by a sterile one-liter bottles, and salinity, temperature, and pH parameters were measured. In the laboratory, the species were identified, purified and counted. Upon initial examination based on morphology, the species was most similar to Amphidinium sp. A total of 13 phytoplankton were identified, to associated with this bloom, the most abundant after N. scintillans dinoflagellate belonging to A. carterae species (600 cells per liter). The single cells of the species was isolated from the water and transferred to Petri dish containing F2 medium, and the unialgae isolate was kept in Phycolab's room at 12D:12L at 25℃±1℃. The finding of this study revealed that A. sp., one of the most harmful algae species (HABs), is presence in the Chabahar Bay region and can cause Bloom in suitable environmental conditions and it may resulted to HABs. According to studies, the high density of this species is associated with the production of toxins and reduced oxygen and it can cause losses in aquatic animals, especially fish. First step in each HAB study is accurete investigation and identification of causative bloom former species in an area and keep alive species in vitro in order to more study. This can be lead to a more precise understanding the life cycle of these bloom former species. and their presence time in the water column, and thus lead to better monitoring and control decisions to prevent or minimize environmental damage and ecosystem and human health.

Amphidinium, bloom, HAB, red tide, toxin.