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1.
We studied assemblages of soft-walled, single-chambered foraminifera (monothalamids) at eight stations in the area of Zernov's Phyllophora Field (ZPF) on the NW continental shelf of the Black Sea. This work is based on samples collected during Cruise 70 of the RV Professor Vodyanitsky and provides the first analysis of the taxonomic composition of monothalamids from this region. These delicate, poorly known foraminifera were found at all stations in the studied area. They were represented by nine forms that are identified to species or genus level as well as 14 undescribed species, nine of which are found in the Black Sea for the first time. Four species, Psammophaga sp., Vellaria pellucida, Goodayia rostellata and Krymia fusiformis, were most abundant, with Psammophaga sp. being the dominant species overall. Previous studies have suggested a link between members of this genus and eutrophication. There are a number of taxonomic parallels between these ZPF assemblages and those from the Adriatic Sea, e.g. the occurrence of the genera Goodayia, Psammophaga and Vellaria, although it is possible that some other taxa are endemic to the Black Sea.  相似文献   

2.
    
We present new data on monothalamous (single-chambered) foraminifera from the Black Sea Crimean shelf zone between Karkinitsky Gulf in the west to the area near Kerch in the east. Within this region we recognized a total of 40 morphospecies; 8 are assigned, in some cases tentatively, to known species and another 9 to known genera, again sometimes tentatively. Twelve species (all undescribed) are reported here for the first time. The most abundant species are Psammophaga sp. (sensu Gooday et al. 2011), Goodayia rostellata Sergeeva & Anikeeva 2008 and Vellaria pellucida Gooday & Fernando 1992, each of which is evenly distributed in all studied areas. The highest species richness of monothalamous foraminifera was observed in the Yalta region. Based on a multivariate analysis of monothalamid assemblage structure and diversity indices [Shannon (H’), Margalef (D’), eveness Pielou (J’), Simpson (1-λ’) and rarefaction ES(n)], we recognized three groups of stations, corresponding to the Western, Southern and Eastern coasts of the Crimean peninsula. The monothalamid assemblages found in each of these coastal regions exhibit different structural features and are distinguished by certain characteristic species.  相似文献   

3.
    
A total of 228 bryozoan species are recorded within the EEZ of the Faroe Islands, 74 of which are new to the area. Analysis of the distribution of the species among six sectors, each characterized by different environmental conditions, showed three faunal assemblages. Variation of the total Faroese bryozoan fauna and of the bryozoan fauna of most sectors, demonstrated significant negative relationships with depth. In general, analysis of the biogeographic composition showed a strong predominance of boreal over arctic species. However, with respect to faunas of each sector, the Norwegian Basin is characterized by a predominance of arctic species and may be regarded as a part of the Arctic Eurasian sub-region of the Arctic biogeographic region. Comparison of the bryozoan species of each sector with the bryozoan faunas of the other 12 areas in the North Atlantic and the neighbouring Arctic regions showed that only the Faroese shelf fauna has significant similarity with part of them, and thus can be regarded as part of the Scandinavian province of the Norwegian high-boreal sub-region of the Atlantic boreal region. Three sectors, the Faroese–Iceland Ridge, the Faroese–Shetland Channel and Norwegian Basin, belong to a transitional zone between the Atlantic Boreal and the Arctic biogeographic regions. The deep south-western sector forms a separate faunal cluster when compared with both the other sectors within the Faroese area and with the faunas of other large geographic areas, and may be regarded as a separate biogeographic zone of the Boreal Atlantic region due to its high proportion of specific species.  相似文献   

4.
A new armoured marine tardigrade, Nodarctus hallucis gen. et sp. nov., is described from specimens collected from sandy beaches of Haterumajima, Ishigakijima and Okinawajima Islands, Ryukyu Archipelago, Japan. It is a member of the rare family Renaudarctidae, which is characterized by a stocky body with dorsal and ventral plates and stumpy legs with digits, claws and accessory filaments. However, the collected animals have prominent characters that differ from the two known species of the family: subdivided dorsal segmental plates I–III lacking lateral processes, an acute caudal spike, indented sensory plates, short spikes and peculiar papillae on legs I–III, basal spikes of legs IV and only two digits on legs IV. These differences justify the erection of a new genus and species for the animal. Morphological affinities with other marine taxa, the function of the leg papillae and the distribution pattern of the new species are discussed.http://zoobank.org/urn:lsid:zoobank.org:pub:041878AA-B437-45BF-80E3-32591D21D965  相似文献   

5.
Abstract

Roszak, Theodore, The Cult of Information. New York: Pantheon Books, 238 pages. $7.95 paperback.  相似文献   

6.
    
Pure cholinergic synaptosomes from the electric organ of Torpedo marmorata have a saturable adenosine uptake mechanism (calculated Km, 3 μM; Vmax, 24 pmol/min/mg prot.). In this preparation, high intracellular calcium elicited by increasing external calcium concentration, potassium depolarization, sodium-calcium exchange inhibition or divalent cation ionophore A23187 action, inhibits adenosine uptake into synaptosomes. The data presented in this paper are consistent with the interpretation that high intracellular calcium participates in the regulation of the high-affinity adenosine uptake system.  相似文献   

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