scholarly journals Revealing the Characteristics of the Antarctic Snow Alga Chlorominima collina gen. et sp. nov. Through Taxonomy, Physiology, and Transcriptomics

2021 ◽  
Vol 12 ◽  
Author(s):  
Francisca E. Gálvez ◽  
Mónica Saldarriaga-Córdoba ◽  
Pirjo Huovinen ◽  
Andrea X. Silva ◽  
Iván Gómez
Keyword(s):  
New Taxon ◽  
King George Island ◽  
Maritime Antarctic ◽  
Antarctic Region ◽  
Snow Algae ◽  
Antarctic Snow ◽  
Snow Alga ◽  
Species Type ◽  
The Antarctic ◽  
Distinct Taxon

Snow algae play crucial roles in cold ecosystems, however, many aspects related to their biology, adaptations and especially their diversity are not well known. To improve the identification of snow algae from colored snow, in the present study we used a polyphasic approach to describe a new Antarctic genus, Chlorominima with the species type Chlorominima collina. This new taxon was isolated of colored snow collected from the Collins Glacier (King George Island) in the Maritime Antarctic region. Microscopy revealed biflagellated ellipsoidal cells with a rounded posterior end, a C-shaped parietal chloroplast without a pyrenoid, eyespot, and discrete papillae. Several of these characteristics are typical of the genus Chloromonas, but the new isolate differs from the described species of this genus by the unusual small size of the cells, the presence of several vacuoles, the position of the nucleus and the shape of the chloroplast. Molecular analyzes confirm that the isolated alga does not belong to Chloromonas and therefore forms an independent lineage, which is closely related to other unidentified Antarctic and Arctic strains, forming a polar subclade in the Stephanosphaerinia phylogroup within the Chlamydomonadales. Secondary structure comparisons of the ITS2 rDNA marker support the idea that new strain is a distinct taxon within of Caudivolvoxa. Physiological experiments revealed psychrophilic characteristics, which are typical of true snow algae. This status was confirmed by the partial transcriptome obtained at 2°C, in which various cold-responsive and cryoprotective genes were identified. This study explores the systematics, cold acclimatization strategies and their implications for the Antarctic snow flora.

Two new Gomphonema species (Bacillariophyta) from the Maritime Antarctic Region

Phytotaxa ◽  
2016 ◽  
Vol 269 (3) ◽  
pp. 209 ◽  
Author(s):  
BART VAN DE VIJVER ◽  
KATEŘINA KOPALOVÁ ◽  
RALITSA ZIDAROVA ◽  
J. PATRICK KOCIOLEK
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Maritime Antarctic ◽  
Antarctic Region ◽  
Diatom Flora ◽  
Ecological Preferences ◽  
The Antarctic ◽  
Scanning Electron

Two new diatom taxa belonging to the genus Gomphonema were recorded during a survey of the Maritime Antarctic freshwater and limno-terrestrial diatom flora: Gomphonema jamesrossense sp. nov. and G.maritimo-antarcticum sp. nov. Detailed light (LM) and scanning electron microscope (SEM) observations are used to characterize the morphology and ultrastructure of the two new Gomphonema taxa. Comparisons with similar taxa and the ecological preferences of each species are added. The revision of these species confirmed the endemic nature of the Antarctic diatom flora.

Newcastle disease virus in penguins from King George Island on the Antarctic region

2010 ◽  
Vol 146 (1-2) ◽  
pp. 155-160 ◽  
Author(s):  
Luciano M. Thomazelli ◽  
Jansen Araujo ◽  
Danielle B. Oliveira ◽  
Luiz Sanfilippo ◽  
Carolina S. Ferreira ◽  
...  
Keyword(s):  
Newcastle Disease Virus ◽  
Disease Virus ◽  
Newcastle Disease ◽  
King George Island ◽  
Antarctic Region ◽  
The Antarctic

Luticola puchalskiana, a new small terrestrial Luticola species (Bacillariophyceae) from the Maritime Antarctic Region

Phytotaxa ◽  
2020 ◽  
Vol 450 (1) ◽  
pp. 85-94
Author(s):  
NATALIA KOCHMAN-KĘDZIORA ◽  
RALITSA ZIDAROVA ◽  
TERESA NOGA ◽  
MARIA OLECH ◽  
BART VAN DE VIJVER
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Morphological Analysis ◽  
New Taxon ◽  
Maritime Antarctic ◽  
Antarctic Region ◽  
Diatom Flora ◽  
Terrestrial Habitats ◽  
Two Populations ◽  
Scanning Electron

During a survey of the terrestrial diatom flora of the Maritime Antarctic Region, an unknown Luticola taxon that could not be identified using the currently available literature was observed on two islands of the South Shetland Archipelago. After a detailed morphological analysis and comparison, the unknown taxon is described as Luticola puchalskiana sp. nov. The new species can be separated from other Luticola species based on its valve dimensions, stria density and the shape of both central and terminal raphe endings. Two populations of the new taxon were observed in samples collected from terrestrial habitats. The morphology of Luticola puchalskiana is elaborately described and illustrated using both light and scanning electron microscopy observations. A comparison is made with a large number of other morphologically similar Luticola species from the entire (sub)Antarctic Region.

Ten new Bacillariophyta species from James Ross Island and the South Shetland Islands (Maritime Antarctic Region)

Phytotaxa ◽  
2016 ◽  
Vol 272 (1) ◽  
pp. 37 ◽  
Author(s):  
RALITSA ZIDAROVA ◽  
KATEŘINA KOPALOVÁ ◽  
BART VAN DE VIJVER
Keyword(s):  
New Species ◽  
South Shetland Islands ◽  
Similar Species ◽  
Maritime Antarctic ◽  
The South ◽  
Antarctic Region ◽  
Shetland Islands ◽  
James Ross Island ◽  
The Antarctic

The present paper describes 10 new diatom (Bacillariophyta) species from the Maritime Antarctic Region. Five of the newly described taxa: Caloneis australis sp. nov., Mayamaea sweetloveana sp. nov., Navicula romanedwardii sp. nov., Sellaphora antarctica sp. nov. and Sellaphora gracillima sp. nov. have been previously reported from the Antarctic Region but were force-fitted into incorrect names. Five other taxa: Chamaepinnularia elliptica sp. nov., Cosmioneis regigeorgiensis sp. nov., Mayamaea tytgatiana sp. nov., Muelleria pimpireviana sp. nov. and Pinnularia pinseeliana sp. nov. are newly discovered taxa. The morphology of all new species is studied using both light and scanning electon microscope observations and compared with similar species from the Antarctic Region and worldwide. Data about the ecology and confirmed Antarctic distribution of the new species are added.

scholarly journals Two additions to the moss flora of the South Shetland Islands in the maritime Antarctic

2018 ◽  
Vol 87 (4) ◽  
Author(s):  
Mariusz Wierzgoń ◽  
Tomasz Suchan ◽  
Michał Ronikier
Keyword(s):  
South Shetland Islands ◽  
King George Island ◽  
Maritime Antarctic ◽  
The South ◽  
Shetland Islands ◽  
Bay Area ◽  
Leading Position ◽  
Glacial Cover ◽  
The Antarctic ◽  
First Time

<em>Tortella fragilis</em> (Drumm.) Limpr. (Pottiaceae) and <em>Bryum nivale</em> Müll. Hal. (Bryaceae) are recorded for the first time from the South Shetland Islands in the northern maritime Antarctic. They were discovered in the Admiralty Bay area on King George Island, the largest island of this archipelago. The two species are briefly characterized morphologically, their habitats are described, and their distribution in the Antarctic is mapped. Discovery of these species has increased the documented moss flora of King George Island to 67 species, strengthening it in the leading position among individual areas with the richest diversity of moss flora in Antarctica. Likewise, <em>T. fragilis</em> and <em>B. nivale</em> represent remarkable additions to the moss flora of the South Shetland Islands, which currently consists of 92 species and one variety, making this archipelago by far the richest bryofloristically amongst large geographic regions of the Antarctic. Comparison of recent (2018) and old (1985) photographs revealed a significant retreat of glacial cover and suggests that the collection site was likely opened for colonization only within the last several decades. The record of <em>T. fragilis</em> is biogeographically relevant, and constitutes an intermediate site between the species’ occurrences in the Antarctic Peninsula and southern South America. The present record of <em>B. nivale</em> is the fourth discovery of the species worldwide, which may be helpful for the future designation of the distribution of this extremely rare species.

Hg distribution and speciation in Antarctic soils of the Fildes and Ardley peninsulas, King George Island

2012 ◽  
Vol 24 (4) ◽  
pp. 395-407 ◽  
Author(s):  
Renato Pereira De Andrade ◽  
Roberto Ferreira Machado Michel ◽  
Carlos Ernerto Gonçalves Reynaud Schaefer ◽  
Felipe Nogueira Bello Simas ◽  
Cláudia Carvalhinho Windmöller
Keyword(s):  
Organic Matter ◽  
Solid Phase ◽  
Soil Depth ◽  
Close Correlation ◽  
Chemical Fractionation ◽  
King George Island ◽  
Maritime Antarctic ◽  
Antarctic Soils ◽  
Ornithogenic Soils ◽  
The Antarctic

AbstractData on the content and speciation of mercury (Hg) in the soils of Antarctica are scarce and vary greatly between the regions studied, but overall Hg concentrations found were generally very low. We investigated the Hg quantity and speciation by solid-phase Hg pyrolysis and chemical fractionation in selected maritime Antarctic soils, comparing ornithogenic and non-ornithogenic areas of the Fildes and Ardley peninsulas of King George Island. The total Hg contents ranged from 4.3–256 ng g-1, and values for ornithogenic soils were the highest recorded for Antarctic soils. A close correlation between Hg and organic matter was observed in the ornithogenic soils, with levels decreasing with depth. In the non-ornithogenic soils, a correlation between Hg content and soil depth was also observed, but the values were found to increase with depth. Thermograms showed that all Hg was in the 2+ oxidation state and was predominantly linked to organic matter, corroborating the chemical fractionation results for the ornithogenic soils. These results show the need for further refined studies about the interactions of Hg with organic matter in order to better understand the biogeochemistry of this metal in the Antarctic environment.

Aulacoseira glubokoyensis sp. nov. (Bacillariophyceae), a new centric diatom from the Maritime Antarctic region

Phytotaxa ◽  
2017 ◽  
Vol 328 (2) ◽  
pp. 149
Author(s):  
ANNA BEATRIZ JONES OAQUIM ◽  
GLEYCI A.O. MOSER ◽  
HEITOR EVANGELISTA ◽  
MARCUS VINÍCIUS LICÍNIO ◽  
BART VAN DE VIJVER
Keyword(s):  
Dendritic Spines ◽  
South Shetland Islands ◽  
Similar Species ◽  
Centric Diatom ◽  
King George Island ◽  
Maritime Antarctic ◽  
Antarctic Region ◽  
Fildes Peninsula ◽  
Shetland Islands ◽  
Scanning Electron

A new centric diatom, Aulacoseira glubokoyensis sp. nov., is described from the Maritime Antarctic region. The morphology of the species is illustrated using detailed light and scanning electron microscopy observations. Its main discriminating features include the presence of typical irregularly shaped dendritic spines, at least two rimoportulae, marginal striae on the discus and a very large Ringleiste. The new species is compared to similar species worldwide. Aulacoseira glubokoyensis has only been observed in a sediment core taken from Profound Lake on the Fildes Peninsula (King George Island, South Shetland Islands).

Freshwater diatoms from some islands in the maritime Antarctic region

1997 ◽  
Vol 9 (4) ◽  
pp. 418-425 ◽  
Author(s):  
Bart Van De Vijver ◽  
Louis Beyens
Keyword(s):  
Cluster Analysis ◽  
Antarctic Peninsula ◽  
Maritime Antarctic ◽  
Antarctic Region ◽  
Freshwater Diatoms ◽  
The Antarctic

A total of 69 diatom taxa, belonging to 24 genera were recorded from thirteen freshwater and moss samples collected in the Antarctic Peninsula region. Marine taxa comprised 26%. Cluster analysis revealed three assemblages. The Nitzschia acidoclinata assemblage occurs on wet mosses; the Luticola muticopsis assemblage is found near penguin rookeries whereas the Pinnularia krookii–Pinnularia microstauron var. elongata assemblage occurs on drier places such as dry mosses and drying mud.

Trans-nonachlor, octachlorostyrene, mirex and photomirex in Antarctic seabirds

1997 ◽  
Vol 9 (4) ◽  
pp. 414-417 ◽  
Author(s):  
Nico W. Van Den Brink ◽  
Elze M. De Ruiter-Dijkman
Keyword(s):  
Early Warning ◽  
Subcutaneous Fat ◽  
Falkland Islands ◽  
King George Island ◽  
Pygoscelis Adeliae ◽  
Antarctic Region ◽  
Antarctic Species ◽  
Organochlorine Pollutants ◽  
The Antarctic ◽  
Adélie Penguins

Octachlorostyrene (OCS) and trans-nonachlor (TNC) were detected in cape petrels (Daption capense) of King George Island, which tallies with their presence in samples of gentoo penguins (Pygoscelis papua) of the Falkland Islands. The detection of TNC in a sample of the Antarctic southern fulmar (Fulmarus glacialoides) implies that the Antarctic region has been contaminated by this compound. Mirex and photomirex were also detected in samples of the cape petrels and southern fulmar, as well as in Adélie penguins (Pygoscelis adeliae) from Hop Island. The ratios of the mirex and photomirex concentrations in the truly Antarctic species from different locations are similar, which suggests that these compounds are diffusely distributed over the continent. The detection of organochlorine pollutants in Antarctic seabirds is an indication that these compounds have a global distribution. Screening of subcutaneous fat of Antarctic seabirds for organochlorines provides an excellent indication of the occurrence of organochlorine pollutants in Antarctica, and as such an ‘early warning’ for the global dispersion of these compounds.

Sulphur and oxygen isotope signatures of dissolved sulphate in freshwater from King George Island, Antarctic Peninsula

2021 ◽  
pp. 1-3
Author(s):  
Yeongmin Kim ◽  
Insung Lee ◽  
Bernhard Mayer ◽  
Guebuem Kim ◽  
Jong Ik Lee ◽  
...  
Keyword(s):  
Oxygen Isotope ◽  
Antarctic Peninsula ◽  
Ice Cores ◽  
Ion Concentration ◽  
King George Island ◽  
Antarctic Region ◽  
Isotopic Signatures ◽  
Natural Processes ◽  
Sulphur Cycling ◽  
The Antarctic

The sulphate ion (SO42-) is one of major species in freshwater as well as seawater, originating from various natural and anthropogenic processes (Krouse & Mayer 2000). Compared to the Northern Hemisphere, where human activities affect the sulphate concentration and isotopic signatures, the contribution of anthropogenic sulphate is likely to be negligible in freshwater and ice cores in the Antarctic region (Patris et al. 2002). This means that the sulphur and oxygen isotope compositions of the dissolved sulphate could hint at information on the sources, formation and deposition due to various natural processes and sulphur cycling in the Antarctic region, especially for the dissolved sulphate in surface waters such as ponds and creeks (Patris et al. 2000, Kim et al. 2017). Here we report the ion concentration and sulphur and oxygen isotope compositions of the dissolved sulphate in freshwater from King George Island in the Antarctic Peninsula, which provide implications regarding the sources of the dissolved sulphate and the sulphur cycling in the Antarctic region.

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