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Number of results: 10
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Abstract

The method of construction and division of dendrites proposed by Florek et al. (1951) was used for defining of the Antarctic biojjeographic areas. The affinity matrices of Knox and Lowry (1977) resulting from the analysis of the distribution of Antarctic Polychaeta and Amphipoda were taken as a basis for dendrite construction The results of the present analysis are compared with the conclusions of these authors and similarities and differences are discussed on the background of the hitherto published biogeographic divisions of Antarctica.

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Authors and Affiliations

Jacek Siciński
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Abstract

This paper presents a new strategy for optimal placement of multi-type FACTS devices with a view to minimize losses besides enhancing the voltage profile using biogeography based optimization. The strategy places three types of FACTS devices that include static VAR compensator, thyristor controlled series compensator and unified power flow controller; and offers optimal locations for placement, type and parameters of the FACTS devices. Test results on IEEE 14, 30 and 57 bus systems reveal the superiority of the algorithm.

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Authors and Affiliations

A. Subramanian
G. Ravi
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Abstract

What are the limits of species distribution in biogeography? How do we reconstruct them for organisms that lived in the past, and how do we study them today? How have the ranges of species changed, and why is this knowledge so important to us?
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Authors and Affiliations

Adam Boratyński
1

  1. Institute of Dendrology, Polish Academy of Sciences in Kórnik
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Abstract

The species diversity of the Bryozoa in Kongsfjorden was determined based on quantitative, depth-stratified (0-30 m) samples collected by SCUBA divers (1996, 1998). One hundred and one species and 16 varieties of the three orders Cyclostomata, Ctenostomata and Cheilostomata - are reported from Kongsfjorden. Ten species are presumably new. The bryozoan fauna of Svalbard is mainly represented by Arctic and boreal-Arctic species and varieties. The few amphiboreal and subtropical-boreal species found most likely reach their northern limit of distribution near Spitsbergen. The distribution of the Bryozoa within Kongsfjorden was determined by depth and location sampled. The number of taxa increased, generally, with depth and distance from tidal glaciers located in the inner fjord. Relative decreases in species number occurred at 15-20 m depth in the middle to outer fjord. This is most likely explained by a change of water mass properties, i.e. a transition from the surface water layer to deeper marine water.

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Authors and Affiliations

Valentina I. Gontar
Haakon Hop
Andrey Yu. Voronkov
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Abstract

The first records from samples from the IceAGE cruise ME85/3 in 2011 include seven species of Caudofoveata with a distribution range in Icelandic waters. From this first cruise of the project, two new records for Iceland have been registered. Psilodens balduri sp. n. is new to science and Falcidens halanychi , with a known distribution in the American North−Atlantic, is new to Iceland. The current study thus increases the number of known caudofoveate species around Iceland to nine.
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Authors and Affiliations

Nina T. Mikkelsen
Christiane Todt
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Abstract

The global zoogeographic distribution of the most widespread peracarid species occurring in three or more ocean basins below 2000 m is analysed. Basing on the published data we investigated 45 peracarid species, which have a most widespread distribution and most likely are cosmopolitan. Thirty−three species have a wide distribution in the Northern Hemisphere. Most species occur in the North Atlantic, however, 16 of these species occur also in the North Pacific, a more limited number of species occurs in the South Atlantic or South Pacific The Southern Ocean displays some special zoogeographic features and 22 widespread species occur there below 2000 m, including highly eurybathic ones. In total, 11 of the analysed species occur in all oceans. Eucopia australis (Lophogastrida), Munneurycope murrayi (Isopoda) and Eurythenes gryllus (Amphipoda) are the species with the widest distributions. Other peracarids occurring in all oceans are: the isopods Paramunnopsis oceanica and Eurycope sarsi , the mysid Caesaromysis hispida the lophogastrid Eucopia unguiculata, the amphipod Mesopleustes abyssorum and the tanaids Exspina typica, Paranarthura insignis and Pseudotanais nordenskioldi . No cumacean species has been reported with an ocean−wide distribution but Campylaspis glabra occurs in the Atlantic, Indian and Pacific oceans. Among plenty of rare species in each order there are only few species with wide distribution records. There is evidence from molecular genetic studies that some of the widespread peracarids represent several cryptic species, however, some, e.g. Eucopia australis , seem to be truly cosmopolitan species. Geography of sampling is biasing our view of biogeography. The history and quality of taxonomic work as well as the reliability of geographic records (quality control of large databases) limits our investigations of widespread or cosmopolitan species as much as the limited knowledge of variation within most species causes difficulties in defining morpho−species with certainty.
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Authors and Affiliations

Angelika Brandt
Magdalena Błażewicz-Paszkowycz
Roger N. Bamber
Ute Mühlenhardt-Siegel
Marina V. Malyutina
Stefanie Kaiser
Claude De Broyer
Charlotte Havermans
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Abstract

Alona protzi is a rare species of Cladocera, occurring in lake littoral throughout Europe. However, little is known about this animal, and so far it has not been included in provisional lists of species found in Finland. In this short report we present our findings of Alona protzi, both recent and subfossil material, as well as one previous, unpublished finding site of the species in Finland. We found three subfossil shells of this species in the bottom sediments of two lakes. In a third lake we found intact animals, an ephippial female and a male, while sampling stony bottom of lake littoral.
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Authors and Affiliations

Mirva Nykänen
Kaarina Sarmaja-Korjonen
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Abstract

Deep−sea benthic Ostracoda (Crustacea) in Icelandic waters are poorly known. Here we report deep−sea ostracode assemblages from the multiple core (MUC) and the epibenthic sledge (EBS) samples collected from Icelandic waters by the first cruise of the IceAGE (Icelandic Marine Animals: Genetics and Ecology) project. Samples from shelf − −edge and lower−bathyal working areas are examined. The results show (1) distinct MUC and EBS faunas due to the large difference in mesh size of MUC and EBS; and (2) distinct shelf−edge and lower−bathyal ostracode faunas. Such remarkable faunal turnover from shelf to bathyal depths is similar to the faunal turnovers reported from depth transects in the adjacent regions of the western North Atlantic Ocean, the Greenland Sea, and the North Sea, but, at the same time, there are certain differences in the faunal composition between the Icelandic waters and these adjacent regions. In addition, we illustrate many Icelandic deep−sea ostracode species with high−resolution scanning electron microscopy and composite all−in−focus stereomicroscopic images for the first time. These results provide important basic information on deep−sea ostracode research and biogeography of this important region connecting North Atlantic proper and Nordic Seas.
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Authors and Affiliations

Moriaki Yasuhara
Maria Grimm
Simone N. Brandão
Anna Jöst
Hisayo Okahashi
Hokuto Iwatani
Alexandra Ostmann
Pedro Martínez Arbizu
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Abstract

A right theropod pedal ungual phalanx II-3 from the Campanian Williams Fork Formation of northwestern Colorado is described, and a combination of features, including the large size, tapering distal tip, robust and stout overall form, triangular cross-section, and a relatively flat ventral surface allows a confident referral to Tyrannosauridae Osborn, 1906. Although this specimen was found in a relatively southern state, the proximal articular surface of this ungual is similar to that of Gorgosaurus libratus Lambe, 1914, a taxon found in the northern state, Alberta. Although based on limited evidence, this may suggest that the range of tyrannosaurids considered endemic to the north of Laramidia extended farther south than previously thought.
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Authors and Affiliations

Chan-Gyu Yun
1

  1. Biological Sciences, Inha University, Incheon 22212, Republic of Korea
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Abstract

Echinoids represent an important component of the Cenozoic marine benthic communities. Their diversity in the Mediterranean area is reviewed within the Late Miocene–Recent, a period of remarkable paleogeographic and paleo- climate changes. Of the 37 genera that lived during the Late Miocene, only Holaster, Pliolampas, and Trachyaster did not survive the Messinian Mediterranean salinity crisis (MSC), indicating that this event was not as drastic as for other marine groups. The presence of Brissopsis within the uppermost Messinian testifies to the existence of fully marine conditions at least towards the end of the MSC. Severe drops in the echinoid diversity, involving the loss of 40% of the Pliocene genera, occurred during the Piacenzian, likely because of the onset of the Northern Hemisphere glaciation. Most of the echinoid extinctions correlate with the crisis of the Mediterranean bivalve assemblage recorded at about 3 Ma. The Early Pleistocene progressive cooling caused the disappearance of further thermophilous shallow-water genera (Clypeaster, Schizechinus, Echinolampas) and allowed the entrance of temperate taxa ( Paracentrotus lividus, Placentinechinus davolii and Sphaerechinus granularis) from the Atlantic. Some deep-water taxa ( Histocidaris sicula, Stirechinus scillae, Cidaris margaritifera), whose Recent relatives are currently restricted to tropical areas, are not found in the area after the Calabrian possibly because of the disappearance of the psychrosphere. The extant Mediterranean echinoid fauna mainly derives from the Late Miocene fauna, reduced after several climatic changes by about 43% at the genus level. The recent increase of the sea surface temperatures allowed the entrance of the Lessepsian Diadema seto sum and confined the deep-water species of Holanthus to the coldest areas of the basin, making this genus endangered.
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Authors and Affiliations

Enrico Borghi
1
Vittorio Garilli
2

  1. Società Reggiana di Scienze Naturali, Via A. Gramsci 109, 42024,Castelnovo Sotto (RE), Italy
  2. PaleoSofia—Research and Educational Service,Via Gagini 19, 90133 Palermo, Italy

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