A Study on the Fine Structure of the Marine Diatoms of Korean Coastal Waters - Genus Thalassiosira 4

Abstract

The marine phytoplankton diatom Thalassiosira species are described from the Korean coastal waters, based on observations of fine structure of its frustules. As a fourth series, this study deals with 5 Thalassiosira species (T. decipiens, T. eccentrica, T. mala, T. nodulolineata, and T. proschkinae). The most striking features of these species are also the form and position of two processes on frustules. There is a central strutted process on valve face except T. nodulolineata, which has a modified one on its center. The external tubes of marginal strutted processes are divided two forms: “pile” form in T. decipiens and T. proschkinae, “short straw” form in T. eccentrica and T. nodulolineata. T. mala does not present the external tubes in valve margin. The labiate processes are located in valve margin except T. proschkinae, which has it on valve face. Of these, three species (T. mala, T. nodulolineata at a final contentration of 5% and T. proschkinae) were newly recorded in the coastal waters of Korea.