Fine Morphology of Some Cyclotella Species from the Freshwater Zone of the Naktong River

Algae > Volume 11(1); 1996 > Article

Algae 1996;11(1): 9-21.

Kyung-Je Cho

Department of Biology, Inje University

ABSTRACT

Cyclotella species are the most common and important in the freshwater zone of the Naktong River. Cyclotella specimens are examined under the light and electron microscope to clarify the taxonomic identity in describing the local species. The following 9 species are included : C. meneghiniana, C. atomus, C. stelligera, C. pseudostelligera, C. woltereckii, C. orientalis, C. glomerata, C. radiosa and one unidentified species. It is necessary to clearly differentiate the small Cyclotella species in the mixed algae assemblages. C. stelligera-group species have a wide range of morphological variations and continuum. Especially, C. stelligera, C. pseudostelligera and C. woltereckii are obscure in their boundary for differentiating the specific identity. Many variations are observed in the morphology such as central zone with stellate areolar fascicles, fultoportular tubular protrusion in the valve margin and the branch pattern of interfascicular costal rib. C. meneghiniana, C. atomus and C. pseudostelligera are abundant as sub-dominant population in the naktong River. Spatial and seasonal abundance of important Cyclotella taxa are monitored from June 1992 to October 1995 throughout the Naktong River.

Key words: Cyclotella, fine morphology, Naktong River