Some hydrozoans (Cnidaria) from King George Island, Antarctica

Zootaxa ◽  
2012 ◽  
Vol 3321 (1) ◽  
pp. 1 ◽  
Author(s):  
HORIA R. GALEA ◽  
DIRK SCHORIES

Twenty one species of shallow-water, benthic hydrozoans, belonging to nine families and fourteen genera, were found ina collection gathered from King George Island, South Shetland islands, during 2010 and 2011. Hydractinia angusta Hart-laub, 1904, Staurocladia charcoti (Bedot, 1908), Candelabrum penola (Manton, 1940), Orthopyxis norvegiae (Broch,1948), and Silicularia pedunculata (Jäderholm, 1904) are redescribed. Additional notes are provided on Schizotricha tur-queti Billard, 1906. Sertularella gaudichaudi (Lamouroux, 1824) is recognized as one of the most widely-distributed member of its genus in Antarctic waters. Taxonomic notes and updated synonymy are provided for some species.

2010 ◽  
Vol 22 (3) ◽  
pp. 271-281 ◽  
Author(s):  
Wojciech Majewski ◽  
Jan Pawlowski

AbstractFour distinctive morphological types can be found among living Globocassidulina in surface sediments of Admiralty Bay (King George Island, South Shetland Islands). The molecular analysis of the SSU and ITS rDNA indicates that they are monospecific and belong to Globocassidulina biora, except for minute forms from deeper than 200 m water depth which probably represent G. subglobosa. The morphological types of G. biora that show doubled or branched apertures, varied test size and shape as well as colour of cytoplasm, represent populations at different stages of ontogenetic development. However, the variability among large G. biora from the same locations is difficult to comprehend. It seems probable that G. biora is the only recent, large, shallow water Globocassidulina represented throughout the Antarctica, while G. crassa is typical for the Magellan region.


Polar Record ◽  
2000 ◽  
Vol 36 (196) ◽  
pp. 3-18 ◽  
Author(s):  
P. Prosek ◽  
M. Janouch ◽  
K. Láska

AbstractThis article presents the results of measurements of the components of ground-surface energy balance (radiation balance, sensible heat flux, latent heat flux, and ground heat flux) taken during the 1994/95 summer season at Poland's Henryk Arctowski Station, King George Island, South Shetland Islands (62°09'42”S, 58°28'10”W). This was the first time that these complex measurements had been taken in the central part of the South Shetlands archipelago. The results are evaluated at the level of daily and seasonal fluctuations. The consequences of energy balance on the temperature conditions of the soil substrata are highlighted. The verification of the degree of influence of a subset of energy-balance components on soil temperature allowed analysis of the relationships among soil temperature, radiation balance, and sensible heat flux. This analysis leads to the conclusion that there is a rapid reaction of the soil temperature to the radiation balance and sensible heat flux to a depth of 5 cm. The boundary atmosphere and soil substrate represent the basic components of the ecotops of the Antarctic vegetation oasis, so these results are interpreted in pedological or botanical studies in the search for environmental influences on the vegetation.


2009 ◽  
Vol 21 (5) ◽  
pp. 439-448 ◽  
Author(s):  
Wojciech Majewski ◽  
Andrzej Tatur

AbstractCribroelphidium webbi sp. nov. is the only adequately described sub-Recent elphidiid foraminifer from Antarctica. In Admiralty Bay (King George Island, South Shetland Islands), it is found at several locations within inner fiord setting at water depths between 33 and 165 m, but most commonly shallower than 100 m. In outer basins this foraminifer is absent. In the cores analysed, C. webbi sp. nov. is present in well-constrained sub-Recent horizons that are clearly related to climate warming and deglaciation. These horizons represent a diachronous facies marker rather than a single stratigraphic layer. Cribroelphidium webbi sp. nov. shows clear association with retreating tidewater glaciers, therefore it is an important sensitive glacier-proximal indicator. It appears that it shares similar ecologic affinities with Cribroelphidium excavatum clavatum, which is widely distributed throughout the Arctic.


2021 ◽  
pp. 1-9
Author(s):  
Paulo E.A.S. Câmara ◽  
Láuren M.D. De Souza ◽  
Otávio Henrique Bezerra Pinto ◽  
Peter Convey ◽  
Eduardo T. Amorim ◽  
...  

Abstract Antarctic lakes have generally simple periphyton communities when compared with those of lower latitudes. To date, assessment of microbial diversity in Antarctica has relied heavily on traditional direct observation and cultivation methods. In this study, sterilized cotton baits were left submerged for two years in two lakes on King George Island and Deception Island, South Shetland Islands (Maritime Antarctic), followed by assessment of diversity by metabarcoding using high-throughput sequencing. DNA sequences of 44 taxa belonging to four kingdoms and seven phyla were found. Thirty-six taxa were detected in Hennequin Lake on King George Island and 20 taxa were detected in Soto Lake on Deception Island. However, no significant difference in species composition was detected between the two assemblages (Shannon index). Our data suggest that metabarcoding provides a suitable method for the assessment of periphyton biodiversity in oligotrophic Antarctic lakes.


2021 ◽  
Vol 10 (48) ◽  
Author(s):  
Sarah Mederos da Silveira ◽  
Sheila da Silva ◽  
Andrew Macrae ◽  
Rommel T. J. Ramos ◽  
Fabrício A. Araújo ◽  
...  

Pseudomonas sp. strain LAP_36 was isolated from rhizosphere soil from Deschampsia antarctica on King George Island, South Shetland Islands, Antarctica. Here, we report on its draft genome sequence, which consists of 8,794,771 bp with 60.0% GC content and 8,011 protein-coding genes.


2014 ◽  
Vol 63 (2) ◽  
pp. 205-210 ◽  
Author(s):  
A. Massalski ◽  
T. Mrozińska ◽  
M. Olech

<i>Lobosphaera reniformis</i> (Wat.) Kom. et Fott (=<i>Chlorella reniformis</i> Wat.) so far known only from Japan, and Papua Island, was for the first time found in Antarctica (King George Island, South Shetland Islands). In laboratory cultures a complete life cycle was obtained, and most of its stages were followed by the electron microscopy. Reproduction is by morphologically different autospores. In some large vegetative cells two Golgi apparatuses lying side by side were observed.


1982 ◽  
Vol 3 ◽  
pp. 233-238 ◽  
Author(s):  
Olav Orheim ◽  
L.S. Govorukha

This paper presents mass-balance results from Deception Island for 1968–69 to 1973–74, from King George Island for the balance years 1969–70 and 1970–71, and from Livingston Island from 1971–72 to 1973–74. The accumulation areas of all localities are in the soaked fades, with a firn/ice transition at King George Island at 12 to 20 m depth. Of the glaciers studied, only “Gl” on Deception Island terminates wholly on land and has a relatively large ablation area. The mass-balance curves are similar for King George Island and Livingston Island, with equilibrium lines at around 150 m elevation. “Gl“ on Deception Island has more negative summer balances, and the equilibrium line ranged from 275 to 370 m during the six balance years. Here, there were no years of positive net mass balance, and large negative net values during the 1970–71 to 1972–73 balance years. This resulted from a lowered albedo caused by ash from the August 1970 eruption. Ash layers from the Deception Island eruptions are also observed on Livingston Island and King George Island, where they form stratigraphic markers in the accumulation areas of the glaciers. Annual balance variations from 1957–58 to 1970–71, based on stratigraphic studies at Deception Island and King George Island, show good correlations, indicating that the variations reflect changes in regional climate.


2012 ◽  
Vol 25 (3) ◽  
pp. 385-386 ◽  
Author(s):  
Marely Cuba-Díaz ◽  
J. Max Troncoso ◽  
Cristian Cordero ◽  
Victor L. Finot ◽  
Mauricio Rondanelli-Reyes

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