Seasonal occurrence of silica-scaled chrysophytes in a small eutrophic swamp, South Korea

Silica-scaled chrysophytes from a small eutrophic swamp (Jinchon swamp) in South Korea were studied using scanning electron microscopy. Samples were collected during the periods August 2004 to August 2005 and February to November 2007. The water temperature and the electrical conductivity varied from 1.75 to 33.2°C and 209 to 916 mS cm-1, respectively. The pH ranged from slightly acidic to alkaline. The cell density of silica-scaled chrysophytes was high in spring and autumn. In total, 35 species of silica-scaled chrysophytes and five unidentified scales (2 Paraphysomonas, 2 Mallomonas and 1 Synura) were observed in the present study. These included 11 species of Paraphysomonadaceae (2 Chrysosphaerella, 7 Paraphysomonas, and 2 Spiniferomonas) and 29 species of Mallomonadaceae (23 Mallomonas), and 6 species of Synuraceae (6 Synura). The total species number was found to be highest in summer samples, followed by spring samples. This is the first report of Paraphysomonas caelifrica, P. eiffelii, and P. subrotacea from Korea, and Mallomonas corymbosa from South Korea.