Distribution of marine, benthic, shell bearing gastropods along the Norwegian coast

Based on literature data and my extensive material from along the coast, the distribution of shell bearing marine, benthic gastropods known from Norwegian waters, is outlined. The geographic area covered goes down to c. 1200 m on the continental slope, and extends from the Swedish border in the south to the Russian border in the north-east. On the slope the distribution is restricted to an area east of 0°, and south of 72° N. Neither the North Sea nor the western ‘slope’ of the Norwegian Trench are included. Systematics and nomenclature follow Clemam (Check List of European Marine Mollusca) closely. The emphasis is on the distribution of each species within the designated area, but taxonomic and nomenclaturial problems are discussed wherever considered relevant. Altogether 365 species level taxa are included, of which 326 are considered as definitely belonging to the Norwegian fauna. The rest are recorded as doubtful, either because only empty shells have been found, or their confirmed distribution falls outside the limits here defined. Of the ‘species’ included, I consider at least 18 to be undescribed, while another 16 were described from Norwegian material after Høisæter (1986) was published. The northern distributional limit is extended for 47 species, while 11 species have received a new southern limit. Sixty six species have a generic name diferent from the one used in Høisæter (1986), while 35 species have another specific name. All changes are listed in the main part of the article, and references are given to the sources for the changes. Four faunal components are recognized: a slope component, species mainly found in negative temperatures on the continental slope, between 500 and 1200 m; an Arctic component, species in Norway almost exclusively found in East Finnmark; a group of species in Norway found only or mainly on the Skagerrak coast or in Oslofjorden; and finally the main group found along most of the coast.publishedVersio

Eumetula brattegardi new name for Eumetula vitrea Høisæter, 2011 not (Dall, 1927) Gastropoda, Caenogastropoda, Triphoroidea, Newtoniellidae)

Eumetula brattegardi nomen novum, is proposed as replacement name for Eumetula vitrea Høisæter, 2011

Relative merits of using numbers and biomass in fish community studies

In descriptions of fish communities, the question of which measure of abundance should be used, whether numbers or biomass, has never been addressed. While both measures are often available, the common practice is to use numerical abundance for such descriptions, without any explicit justification for this choice. In order to contribute to the clarification of this issue, we have compared correspondence analyses/TWIA-classifications performed on both the numerical density and the biomass of the same trawl catches from a region off the western coast of Africa. The situation in which the quantitative aspect of the samples is disregarded, represented by presence/absence analyses, is illustrated for comparison. As it appeared likely that the length of the ecological or biogeographical 'gradient' would be of importance in how different the results of the 2 abundance measures would emerge, a series of subsamples of the total material, representing shorter ecological gradients, was also analysed. The analyses show that in most situations the choice between numbers and biomass matters little. However, in the case of short ecological 'gradients', when all or the large majority of species are common to all samples studied, and the individual fish sizes are different, there may be a marked difference in the patterns shown by the alternative measures of abundance

An annotated check-list of marine molluscs of the Norwegian coast and adjacent waters

This check-list is a compilation of the marine molluscs recorded from Norway and the abyssal depths of the Norwegian Sea. Molluscs not recorded from the Norwegian fauna but found on the North Sea plateau, the British North Sea coast, the Swedish west coast, and in Danish waters are also included. Distributional data are provided for each species. Most commonly used synonyms are listed, together with type species for each accepted generic name. Systematical code numbers are included for easy retrieval of information. An alphabetical index of all generic names mentioned concludes the check-list. Recent taxonomic alterations and all distributional records are documented by literature references

Distribution of marine, benthic, shell bearing gastropods along the Norwegian coast

Based on literature data and my extensive material from along the coast, the distribution of shell bearing marine, benthic gastropods known from Norwegian waters, is outlined. The geographic area covered goes down to c. 1200 m on the continental slope, and extends from the Swedish border in the south to the Russian border in the north-east. On the slope the distribution is restricted to an area east of 0°, and south of 72° N. Neither the North Sea nor the western ‘slope’ of the Norwegian Trench are included. Systematics and nomenclature follow Clemam (Check List of European Marine Mollusca) closely. The emphasis is on the distribution of each species within the designated area, but taxonomic and nomenclaturial problems are discussed wherever considered relevant. Altogether 365 species level taxa are included, of which 326 are considered as definitely belonging to the Norwegian fauna. The rest are recorded as doubtful, either because only empty shells have been found, or their confirmed distribution falls outside the limits here defined. Of the ‘species’ included, I consider at least 18 to be undescribed, while another 16 were described from Norwegian material after Høisæter (1986) was published. The northern distributional limit is extended for 47 species, while 11 species have received a new southern limit. Sixty six species have a generic name diferent from the one used in Høisæter (1986), while 35 species have another specific name. All changes are listed in the main part of the article, and references are given to the sources for the changes. Four faunal components are recognized: a slope component, species mainly found in negative temperatures on the continental slope, between 500 and 1200 m; an Arctic component, species in Norway almost exclusively found in East Finnmark; a group of species in Norway found only or mainly on the Skagerrak coast or in Oslofjorden; and finally the main group found along most of the coast

The pyramidellidae (gastropoda, heterobranchia) of Norway and adjacent waters. A taxonomic review

This monograph gives a taxonomic treatment of all 54 ‘species’ of Pyramidellidae reported from Norwegian and adjacent waters. Two species, Parthenina wikanderi n.sp.and Eulimella frielei n.sp., are described as new and three are ‘resurrected’ from synonymy. Nine previously described species are reported as new records for Norway, while three species are removed from the Norwegian fauna list. All species are illustrated with LM photographs (and, in a few cases, SEM photographs), and drawings of soft parts and operculae when available. An attempt is made to upgrade the generic taxonomy of the species included

A taxonomic review of the Norwegian species of Raphitoma (Gastropoda: Conoidea: Raphitomidae)

The problematic conoidean genus Raphitoma s.l. in inshore Norwegian waters is revised based on fresh material from all along the coast of Norway. This largely shallow water group is represented by at least six species in Norwegian waters of which two, Raphitoma obesa n.sp. and R. maculosa n.sp. are described as new, and another Raphitoma aequalis (Jeffreys, 1867) is reported from Norway for the first time. The taxonomic and nomenclatural status of R. reticulata (sensu Jeffreys 1867) and R. asperrima (sensu Forbes & Hanley 1853) are discussed. Empty shells of several additional species indicate that the number of Raphitoma-species living in the North East Atlantic will be further increased in the future. The morphological variability of each species is described if possible. Shell morphology, including microsculpture and protoconch details as deduced from LM photographs, are used for distinguishing the species. Some easily observable behaviour and soft part morphology features were found to be promising areas for further studies

Xandarovula patula (Gastropoda: Ovulidae) new to Scandinavia

In August 2009 six specimens of the ovulid gastropod Xandarovula patula (Pennant, 1777) (formerly known as Simnia patula Pennant, 1777), were found in dredge samples from a locality west of Smögen in western Sweden (58°22′N 11°05′E). In June and November 2010 a total of three specimens of the same species were found in dredge samples from near Svelgen Bridge, Øygarden, Hordaland, western Norway (60°27 ′N 04°57 ′E). Several small colonies of the presumed prey species, Alcyonium digitatum Linnaeus, 1758 and Tubularia indivisa Linnaeus, 1758, were found in the same dredge hauls. Xandarovula patula has been recorded from the Atlantic coast of southern Spain to the western end of the English Channel, with scattered records from the west coasts of Ireland and Britain, as far north as the Orkneys. More recently it has been reported from most Irish coasts, several parts of the Scottish coast and also from some places in the North Sea. Until now there have been no confirmed records from Scandinavian waters. The specimens recorded here may indicate recent immigration of a southern species due to warmer water temperatures