Five red tide species in genusProrocentrum including the description ofProrocentrum donghaiense Lu SP. nov. from the East China Sea

A new planktonic dinoflagellate,Prorocentrum donghaiense Lu sp. nov., is described in the present paper. The water sample was collected from the Changjiang Estuary, the East China Sea. The species identification is based on shape, size, surface micro-morphology, ornamentation of thecal plates and the architecture of the periflagellar area and the intercalary bands as seen by light and scanning electron microscope.Prorocentrum donghaiense Lu sp. nov. is compared with other prorocentrum species with respect to morphological characteristics and bloom behavior. It is not known whetherProrocentrum donghaiense Lu sp. nov produces phycotoxins like some other Prorocentrum species. Four other red tide species in the family Prorocentraceae (Dinophyceae), namelyP. balticum, P. minimum, P. micans, P. triestinum, were examined and identified by light and scanning electron microscope. They have been recorded as bloom-forming species. Some aggregates ofProrocentrum are observed at the end of blooms. An event of strong discoloration caused byP. donghaiense could be detected by satellite sensor in the East China Sea in the late spring of 1995.