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Yokosuka, Japan

Fukushima H.,Institute of Phycology | Kimura T.,Institute of Phycology | Ko-Bayashi T.,Institute of Phycology | Yoshitake S.,Shonan Junior College | Lepskaya E.V.,Institute for Fisheries Research and Oceanogaphy
Antarctic Record | Year: 2012

Navicula streckerae was recorded in two locations of northern Germany and the Arctic Ocean. According to the findings of this taxon from Lake Khovsgol (Mongolia) and Kamchatka (Russia) by our investigations, this taxon distributed northward from latitude 50°N. on the Eurassian Continent and is considered to be a circumboreal diatom. This taxon is divided into three types, namely the Arctic Ocean type, the Weser River type and the Kinzig River type according to the valve morphology. In this study we compare these three types in the samples from Europe and Kamchatka focusing on the valve form and sizes. Though the density of lineolae composing striae is one of the important characteristics to classify the species, there are few records of this point. We investigate this point in detail in the specimens from Europe and Kamchatka. Consequentry the two extreme values, short striae forming the cental area and the area including Voigt discontinuities, should be excluded when measuring the density of lineolae to obtain a stable value. © 2012 National Institute of Polar Research. Source


Fukushima H.,Institute of Phycology | Kimura T.,Institute of Phycology | Ko-Bayashi T.,Institute of Phycology | Fukushima S.,Nagasaki 1 14 5 | Yoshitake S.,Inukura 2 39
Antarctic Record | Year: 2012

We identified 35 taxa of Navicula sensu lato in materials from inland waters at Herschel Island, Smoking Hills, Holman, Byron Bay and Cambridge Bay while sailing across the reverse course of the Northwest Passage in July and August 1997. We found 20 taxa of Navicula, 4 of Chamaepinnularia, 2 each of Craticula and Placoneis, and 1 each taxon of Aneumatus, Caloneis, Fallacia, Naviculadicta, Parlibellus, Pinnuavis, and Sellaphora. The materials contain cosmopolitan species intermingled with subalpine or mountain species and endemic species (Table 1). Although samples were collected from inland waters, brackish or marine species (see Table 1) were mixed with fresh-water species similar to those reported from Antarctica. The occurrence of brackish-water and marine species is though to be made possible by the eolian transport of salt to inland water bodies. We propose the following seven new combinations: Chamaepinnularia soeherensis var. hassiaca, Chamaepinnularia soeherensis var. inflata, Chamaepinnularia soeherensis var. linearis, Chamaepinnularia soeherensis var. muscicola, Placoneis amphibola var. amphibola f. alaskaensis, Placoneis amphibola var. amphibola f. rectangularis, and Placoneis amphibola var. arctica. © 2012 National Institute of Polar Research. Source


Fukushima H.,Institute of Phycology | Kimura T.,Institute of Phycology | Ko-Bayashi T.,Institute of Phycology
Antarctic Record | Year: 2013

Very few comparative taxonomic studies on Arctic and circumboreal diatoms have been conducted in recent years. During the period of Aug. 1996 to 1999 (table 1), we visited a number of island within the Arctic Circle (Baffin Island, Coburg Island, Beechey Island, Devon Island, Cornwallis Island, Spitsbergen, Greenland) and collected specimens of 20 algal taxa (identified by micrograph observations) of Navicula sensu lato (Chamaepinnularia: 6 taxa, Geissleria: 1 taxon, Luticola: 1 taxon, Navicula: 11 taxa, Placoneis: 1 taxon). © 2013 National Institute of Polar Research. Source

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