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Number of results: 5
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Abstract

Bryozoans were collected in Kongsfjorden (79°N and 12°E) in the summer seasons of 1997, 1998, and 1999. In the total of 44 grab, dredge, and SCUBA diving samples 143 taxa were determined: 123 species, 17 to the generic and 3 to the family level. In the investigated material were 24% Arctic species and 66% boreal-Arctic species. This suggests a rather Arctic nature of the fjord. A few boreal species indicate the influence of warm water masses (West Spitsbergen Current). The majority of species (76%) have an encrusting life form. There were 5 species with a frequency of occurrence higher than 20%. These are Electra crustulenta var. arctica (31.82%); Cylindroporella tubulosa (27.27%); Tegella arctica (22.73%); Tegella armifera (20.45%); and Hippothoa divaricata var. arctica (20.45%). Among all identified species 23 were recorded for the first time in the area of Svalbard archipelago. Most (79%) of newly noted species have Arctic distributions. The lower sampling effort of previous researchers most likely accounts for the present enrichment of the list of Bryozoa of Kongsfjorden.
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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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Abstract

An additional account on the Oligocene cyclostome Bryozoa has been made from the glaciomarine sediments of the Low Head Member (= Pecten conglomerate of Barton 1965) of the Polonez Cove Formation on King George Island (South Shetland Island, West Antarctica). The following genera have been recognized for the first time in Paleogene of Antarctica: Crista, Bicrisia, Exidmonea, Filisparsa and Mecynoecia. Paleoecological interpretation of the bryozoan assemblage implies that the fauna lived in shallow water at a depth of around 50 m.
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Abstract

A few specimens of a macroporid bryozoan were collected, from the Eocene La Meseta Formation from Seymour (Marambio) Island, Antarctic Peninsula. Based on the morphology of the studied specimens Macropora antarctica sp.n. has been erected. This is the stratigraphically oldest species of the genus which exhibits a number of similarities with the Tertiary fossils and some Recent macroporids reported from the Southern Hemisphere i.e., Australia, New Zealand and South America.
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Abstract

A sequence of glacial deposits up to 4 m thick unconformably overlies the Eocene La Meseta Formation on the Seymour Island plateau (meseta) and forms a lithostratigraphically distinct unit in the succession of the James Ross Basin, which is formally named here as the Weddell Sea Formation. The formation is thus far known only from Seymour Island. This is a terrestrial melt-out till which contains abundant erratics and also reworked Cretaceous–Tertiary micro- and macrofossils within a silty clay matrix. The terrestrial origin of this till is shown by glacial striations at the base of the unit. The largest erratics (up to 3 m in diameter) are composed of plutonic (granitoids) and metamorphic (gneiss and crystalline schist) rocks of the Antarctic Peninsula provenance. Smaller in size and much more numerous are erratics of volcanic rocks, represented by andesite, basalt and corresponding pyroclastics of the James Ross Island Volcanic Group. Less common are erratics of sedimentary rocks, sometimes bearing fossils derived from the underlying Tertiary and Cretaceous strata. A few erratics from the top of the studied sequence are conglomerates of the Cockburn Island Formation with a foraminifer fauna. These are the youngest clasts within the Weddell Sea Formation. The presence of the Pliocene index fossil Ammoelphidiella antarctica Conato et Segre, 1974 indicates a lower age limit of latest Pliocene or earliest Pleistocene age. The upper age limit of the formation has not been established. An encrusting, unilamellar, colony of the bryozoan Escharella Gray, 1848 has been found on the one of erratics from the Weddell Sea Formation. This is the first fossil record of this genus in Antarctica.
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