Three new diatom species are described under the new genus Tropidosiphonus, separable from those hitherto assigned to Mediaria Sheshukova-Poretskaj a, which should now recur to the araphid category based on the lack of raphe system. They are Tropidosiphonus lanceolatus, T. secundus and T. tenuiconstrictus, all of which share a common appearance, bearing otherwise tubular endings. These internal tubes, termed helictosiphon characteristic of the new genus, is introduced from the evidence of SEM details as a new componental organelle of raphe system.
A taxonomic study on the diatoms from the Kwang River (Kwangchun), less polluted, in S. Korea is reported. In this paper 83 taxa with exception for Naviculaceae are described, which are classified into 65 species and 18 varieties belonging to 26 genera,9 families,3 suborders and 2orders. Eighteen of these taxa are new for Korea.
A taxonomic study on the diatoms from the Kwang River (Kwangchun), less polluted, in S. Korea is reported. In this paper 99 taxa of Naviculaceae classified into 87 species and 12 varieties of 16 genera are described. Eighteen of these taxa are new for Korea. For ‘Navicula yuraensis’the condition for valid publication is fulfilled. Pleurosigma negoroi sp. nov. is formally described.
The diatoms of brackish water in the Kase River (Kasegawa) Estuary, Saga Prefecture, Japan were investigated. A total of 238 taxa, distributed among 50 genera, were recorded in an epilithic diatom sample. In the diatom assemblage, Hydrosera triquetra was a predominant taxon and the best represented genera were Bacillaria, Gyrosigma, Nitzschia and Synedra. In nineteen plates, all taxa are depicted by microphotographs.
Diatom pop-illations from the River Kanching, Templer Park, Malaysia were investigated from ugust 13 to November 5,1991. The 97 taxa from 27 genera were recorded. Gomphon ema 7arolinense, G. clevei, G. acuminatum and G. longiceps were major diatoms in this river. The following four taxa are new record for Malaysia: Aulacoseira ambigua, A. subarctica, Anomoeoneis; erians var. apiculata and Navicula monmouthiana-stodderi var. monmouthiana-stodderi.
The diatom Fragilaria striatula was not known in Japan before the summer of 1983. In October of the year, this diatom was found in seawater collected from the coast of Kushiro in Hokkaido. After the discovery of this diatom in northern Japanese waters, this pelagic species has been known as common in neritic waters from the Straits of Tsugaru to the east coast of Hokkaido, especially in autumn and winter.