Filamentous algae are often visible on the carapaces of freshwater turtles and these algae are dominated by a few species with varying geographic distributions. Compared to filamentous algae, little is known about the much more speciose microalgae on turtles. Our objectives were to compare the diatom flora on a single turtle species (the common snapping turtle, Chelydra serpentina) across part ...

Chitin is a globally abundant polymer widely distributed throughout eukaryotes that has been well characterized in only a few lineages. Diatoms are members of the eukaryotic lineage of stramenopiles. Of the hundreds of diatom genera, two produce long fibers of chitin that extrude through their cell walls of silica. We identify and describe here genes encoding putative chitin synthases in a vari...

Dinoflagellates are known to possess chloroplasts of multiple origins derived from a red alga, a green alga, haptophytes, or diatoms. The monophyletic "dinotoms" harbor a chloroplast of diatom origin, but their chloroplasts are polyphyletic belonging to one of four genera: Chaetoceros, Cyclotella, Discostella, or Nitzschia. It has been speculated that serial replacement of diatom-derived chloro...

We studied time-series fluxes of diatom particles from 4 October 2010 to 18 September 2012 using bottomtethered moorings with two sediment traps deployed at 180 and 1300 m depths at Station NAP (75 N, 162W; 1975 m water depth) in the western Arctic Ocean. This paper discusses on the relationship of time-series diatom fluxes to satellite-based sea-ice motion and simulated hydrographic variations...

A major flooding event that occurred during October–November 2012 caused major changes in the Kowie River hydromorphology and aquatic communities. The aim of our study was to identify the environmental variables that structure riverine benthic diatom communities at upstream and downstream locations 25 km apart on the Kowie River, South Africa. This was undertaken using tiles as artificial subst...

The intricate, genetically controlled biosilica nano- and micropatterns produced by diatoms are a testimony for biology's ability to control mineral formation (biomineralization) at the nanoscale and regarded as paradigm for nanotechnology. Previously, several protein families involved in diatom biosilica formation have been identified, and many of them remain tightly associated with the final ...

The hydrology of shallow lakes (and ponds) located in the western Hudson Bay Lowlands (HBL) is sensitive to climate warming and associated permafrost thaw. However, their biological characteristics are poorly known, which hampers effective aquatic ecosystem monitoring. Located in northern Manitoba along the southwestern coast of Hudson Bay, Wapusk National Park (WNP) encompasses numerous shallo...

Diatom assemblages were analysed to clarify the changes in sedimentary environments caused by the Holocene sea level changes, and the results were cross-checked with information from the field observations of sedimentary facies. Diatoms were grouped into three ecological categories; marine, brackish and freshwater. Based on the ecological spectrum of the diatoms, the sediments were divided into...

the purpose of this study was to investigate the distribution and biodiversity of diatoms during different seasons and their correlation with water quality parameters in helleh river estuary, bushehr, persian gulf. samples were taken in mid-season from summer 2011 to spring 2012 during a one-year period from different stations. results showed that diatoms mostly comprised of bacillariophyceae, ...

Diatom dissolution in surface sediment samples from two regional lake datasets in the Northern Great Plains (NGP; n 5 64) and West Greenland (n 5 40) is assessed using a morphological approach categorizing valves during routine diatom analysis. Two dissolution indices are derived to parameterize diatom dissolution, and, when compared between two analysts in a blind test, show good correspondenc...