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Six strains of three different Gonyaulax species were established by isolating cells from the Korean coastal area and the East China Sea, and their morphologies and molecular phylogenies based on SSU and LSU rRNA gene sequences were examined. In addition, the growth responses of the Gonyaulax species to changes in temperature and salinity were investigated. Based on morphological features and phylogenetic positions, Gonyaulax whaseongensis and G. polygramma were identified, and G. geomunensis sp. nov. is proposed in this study. These species displayed the plate formula typical for Gonyaulax, but G. polygramma and G. geomunensis sometimes showed a small intercalary plate (1a) surrounded by plates 2', *3' and 3". G. geomunensis was morphologically characterized by an S-type ventral organization, descending with a displacement of one cingulum width and bearing one, two or three prominent antapical spines of similar size. The cell surface, which was distinct from other Gonyaulax species, was thick and heavily reticulated into numerous polygonal areas. The reticulation was deeply excavated. The phylogenetics revealed that G. geomunensis and G. whaseongensis belong to different clades, and that there are two ribotypes of G. polygramma, which were morphologically indistinguishable. These species had a close phylogenetic relationship to G. hyalina, and all of them were characterized by dextral torsion. G. whaseongensis, G. polygramma and G. geomunensis had different growth responses to changes of temperature and salinity, respectively, indicating that morphological and phylogenetic identification of Gonyaulax species can be supported by ecological niches. [ABSTRACT FROM AUTHOR]

A hybrid material of diazoresin (DR) and ethylenediaminetetraacetic acid d isodium salt (EDTA-2Na) coated on to silica particles were synthesized and applied as adsorbents. The study of UV-vis spectrum revealed th at DR and EDTA could be successfully m odified on to silica. The effect of initial pH value of aqueous solution and dosage of th e adsorbents on the adsorption capability for heavy metal Cu(ll) ion were investigated and discussed. [ABSTRACT FROM AUTHOR]

A new species, Pentapharsodinium jinhaense sp. nov., was established by incubating resting cysts, which were collected from trap samples from Jinhae-Masan Bay, Korea. The resting cysts of P. jinhaense were spherical or ovoidal, with a large reddish pigment body and a thick wall covered by numerous needle-shaped calcareous crystals. The size, shape and plate tabulation of motile cells that germinated from the resting cysts were similar to those of Pentapharsodinium tyrrhenicum and Ensiculifera carinata; however, the motile cells had a spine located in the anterior sulcal plate and many pores and spines on the thecal surface. Molecular phylogenetic analysis using internal transcribed spacer and 5.8s rDNA showed that P. jinhaense was closely related to P. tyrrhenicum. Large subunit ribosomal DNA sequences also revealed that P. jinhaense was nested within Pentapharsodinium and formed a strongly supported clade with Pentapharsodinium dalei and P. tyrrhenicum. [ABSTRACT FROM AUTHOR]

Two morphologically distinct species, Brigantedinium majusculum and Trinovantedinium applanatum, have been suggested as a cyst stage of Protoperidinium pentagonum; however, the cyst-theca relationships are still virtually undefined. In this study, we re-examined the motile stage of B. majusculum via thecal plate analysis together with a molecular phylogenetic analysis based on partial large-subunit ribosomal DNA gene sequences. The morphological features of motile cells germinated from B. majusculum were identical to those of Pr. sinuosum, and the molecular phylogenetic analysis showed that the germinated cells and B. majusculum are closely related to Pr. pentagonum and Pr. latissimum as a sister group. Additionally, high sequence divergences were observed between the germinated cells and B. majusculum as well as Pr. pentagonum and Pr. latissimum (18.0-19.5% according to P-values and 20.7-22.9% according to Kimura two-parameter values). On the basis of these results, our study indicates that B. majusculum should be accepted as the cyst of Pr. sinuosum. [ABSTRACT FROM AUTHOR]

The genus Tovellia contains approximately eight described species. A new species, Tovellia paldangensis sp. nov. was observed by incubation of a cyst from sediment collected in the Paldang Dam Lake in Korea. The vegetative cells of this new species were 20.0-27.0 μm long, 18.0-23.0 μm wide, and 17.0-20.5 μm thick. The cingulum was displaced by one cingulum width, the nucleus was located in the posterior part of the cell, and the chloroplasts were numerous and in yellow-green in color. A prominent red body was present on each side of the cingulum. The amphiesma had numerous thin polygonal plates that were arranged in three to four latitudinal series on the epicone and in two to three series on the hypocone. A narrow apical line of plates (ALP) extended over the anterior part of the cell, approximately in a 3/4 of the ventral side and 1/4 of the dorsal side of the epicone. The antapical plate was usually hexagonal. T. paldangensis was clearly differentiated from the other species of Tovellia by the morphology of its vegetative cell (two red bodies, and the ALP lines on each side separated by a row of four to five elongate plates) and the resting cyst (typically covered with numerous short solid spines). Phylogenetic analysis based on partial large subunit ribosomal RNA gene sequences indicated that T. paldangensis was most closely related to T. coronata, T. sanguinea, and T. aveirensis. [ABSTRACT FROM AUTHOR]