The  major  group  which  contains  all  the  organisms   that  are  commonly  termed  Dinoflagellates  is  called  the  division  Pyrrophyta  or  Dinophyta  in  botanical  systems  and  the  order  Dinoflagellida  or  Dinoflagellata  in  zoological  systems.   Most dinoflagellates  are  biflagellated  solitary  planktonic cells. Identification of species in water samples was usually done by using differential interference contrast (DIC), which revealed especially well lighted thecal structures. The microscope was equipped out on a Zeiss Axioskop microscope with a Mc 80 microphotosystem. For the apparent three-dimensional image, scanning electron microscope (JEOL JSM-840A SEM) was used.

Results/Conclusions A taxonomic survey of the dinoflagellate family, Triadiniaceae Dodge was conducted in the coastal waters of Korea. Three species were identified and described, which were Triadinium orientale (Lindemann)Dodge, Triadinium polyedricum (Pouchet) Dodge and Triadinium sphaericum (Murray and Whitting) Dodge.