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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.
Abstract: A rich coral‐associated decapod assemblage is recorded from the ‘Depiru Beds’ of the upper part of the Upper Coralline Limestone (Messinian, Upper Miocene), from the island of Malta. Nineteen species within 17 genera have been discovered, where 14 genera are new for Malta. Four new species are described, namely Micippa annamariae sp. nov., Pilumnus scaber sp. nov., Panopeus muelleri sp. nov. and Herbstia melitense sp. nov. Herbstia melitense sp. nov. constitutes the first record of the genus from the fossil record in the Mediterranean region. This discovery more than doubles the number of known fossil decapod species from Malta. The fossil bivalve Jouannetia (J.) semicaudata Des Moulins, 1830 and the extant decapod Maja goltziana D’Oliveira, 1888, are also recorded for the first time from Malta. Other Neogene coral‐associated decapod assemblages are investigated and correlated with the new assemblage from Malta. The migration of taxa between the Mediterranean region and the Paratethys, particularly during the Lower Badenian (Langhian), is evidenced by the strong affinity of the Maltese decapod assemblage with that of the Middle Miocene Badenian assemblages from Hungary, Poland and Ukraine. Upper Miocene, Messinian assemblages from Spain, Algeria and Morocco are also similar to that from Malta.  相似文献   

3.
Radiolarian data provide important age constraints on the development of terranes within the New England orogen and have implications for existing tectonic models. Most radiolarian assemblages recovered from the orogen are of Late Devonian to Early Carboniferous ages. Albaillellaria comprise a minor proportion of the faunas present but have major biostratigraphic significance.Holoeciscus Foreman,Helenifore Nazarov and Ormiston,Circulaforma Cheng,Ceratoikiscum Deflandre,Protoalbaillella Cheng, andAlbaillella Deflandre, two new genera and three new species are found at various stratigraphic levels. Eleven radiolarian assemblages are recognised. In stratigraphic order these are theHelenifore laticlavium-Ceratoikiscum planistellare, Protoholoeciscus hindea, Holoeciscus formanae, Paraholoeciscus bingaraensis,Ceratoikiscum umbraculum, Protoalbaillella anaiwanensis, Albaillella paradoxa, Albaillella undulata-Albaillella indensis,Albaillella indensis-Albaillella furcata, Albaillella cartalla-Albaillella thomasi andCirculaforma omicron assemblages. There is an apparent biostratigraphic succession amongst the Albaillellaria in the New England orogen in whichProtoholoeciscus hindea n. gen. n. sp. is transitional betweenCeratoikiscum Deflandre andHoloeciscus Foreman andParaholoeciscus bingaraensis n. gen. n. sp. is transitional betweenHoloeciscus Foreman and theAlbaillella paradoxa Deflandre group.  相似文献   

4.
在黔西水城地区的K576井长兴组共鉴定钙藻3属3种,包括Gymnocodium bellerophontis、Permocalculus sp.和Tauridiumkurdistanensis;有孔虫8属10种,其中(虫筳)类2属2种,有孔虫动物群主要由Reichelinasp.indet.、Nankinella sp.、Pachyphloia schwageri、Pachyphloia sp.、Geinitzina sp.、Nestellorella sp. indet.、Howchinella sp.、Hemigordius aff. saranensis、Hemigordius sp.和Midiella sp. indet.组成。将本井按照生物特征分为有孔虫-钙藻-介形虫组合、有孔虫-腕足类-介形虫组合、介形虫-双壳类-腹足类组合、有孔虫-钙藻-双壳类组合、有孔虫-腕足类-介形虫组合、有孔虫-钙藻-双壳类组合和介形虫组合等7个组合。按照层序地层划分、垂向沉积序列特征和测井资料的分析,有孔虫-钙藻-介形虫组合(SQ3-3)和有孔虫-腕足类-介形虫组合(SQ3-4)时期地层为三角洲前...  相似文献   

5.
Synopsis Fish traps were used to quantify the distribution and abundance of the Lutjanidae and Lethrinidae on reefs across the central Great Barrier Reef. The assemblages of fishes on inshore reefs were distinctive from those on midshelf and outershelf reefs. There were significantly fewer individuals of the Lutjanidae and Lethrinidae inshore and all species examined displayed significant cross-shelf changes in abundance. These significant cross shelf changes in abundance were due to an absence or low abundance of individuals of a species at one or more cross shelf locations, with many species present in only one location on the continental shelf. The genera Aprion, Lutjanus, Macolor, Symphorichthys, Symphorus, Gnathodentex, Gymnocranius, Lethrinus and Monotaxis were all characteristic of the shallow shelf waters less than 100 m. In contrast, species of the genera Paracaesio, Pristipomoides and Wattsia were characteristic of the intermediate depths (100–200 m) and the deeper outer reef slope waters in excess of 200 m were characterised by species of the genus Etelis.  相似文献   

6.
Silurian trilobites of Ludlow and P?ídolí age are described from sections in southern Uzbekistan and from adjacent parts of Tajikistan. They belong to 22 species (10 named and 12 under open nomenclature) distributed among 13 genera belonging to the families Proetidae, Tropidocoryphidae, Aulacopleuridae, Scharyiidae, Cheiruridae, Encrinuridae and Odontopleuridae. The following new species are described: Interproetus pentaxus, Paleodechenella turkestanica, P. zaaminicus, Cromus tamchii and Leonaspis nuratensis. The generic associations from the mid Ludlow bear a striking resemblance to coeval ones from Bohemia, and include genera otherwise known only from that region or from adjacent parts of central Europe. The trilobite faunas from the late Ludlow and P?ídolí series are much less diverse and are dominated by genera of the Warburgellinae (Tropidocoryphidae), which include one species common to Vaigatch Island in the Russian Arctic, and Podolia, Ukraine. The closest links of the diverse central Asian mid Ludlow faunas are therefore to central Europe, whilst the sparser younger Ludlow and P?ídolí faunas, such as they are, suggest closer links to Baltica.  相似文献   

7.
Composition and distribution of asteroid and ophiuroid assemblages were investigated by means of Agassiz trawl catches at 34 stations in 220- to 1,200-m depth in the Weddell Sea and at 17 stations in 90- and 830-m depth off Northeast Greenland. A total of 86 species (48 sea stars, 38 brittle stars) were identified in the Weddell Sea whereas off Northeast Greenland a total of 26 species (16 sea stars, 10 brittle stars) were recorded. In both study areas, brittle stars were numerically more important than sea stars, and abundances generally decreased with water depths. Multivariate analyses revealed a conspicuous depth zonation of sea and brittle stars off Greenland. Very high abundances of Ophiocten sericeum and Ophiura robusta characterized the assemblages on shallow shelf banks whereas in greater depths Ophiopleura borealis, Ophioscolex glacialis and Ophiacantha bidentata became dominant, albeit at significantly lower densities. Mass occurrences of brittle stars, such as those recorded on Greenlandic shelf banks, have not been discovered in the Weddell Sea, where distinct assemblages were discriminated in deep shelf trenches as well as on the eastern and southern shelf. Ophioplocus incipiens, Ophiurolepis martensi and Ophiurolepis brevirima were the most prominent species on the eastern shelf. Ophiacantha antarctica, Ophiurolepis gelida and Ophionotus victoriae on the southern shelf, and Ophiosparte gigas as well as the asteriod Hymenaster sp., in the shelf trenches. Overall, the Weddell Sea housed conspicuously more asterozoan species than the waters off Greenland. Higher species diversity was also evident at both a regional and local scale, especially for the eastern Weddell Sea shelf. However, because many species from the Weddell Sea are closely related, the Weddell Sea assemblages were not significantly different from the Greenland ones in terms of taxonomic diversity and distinctness. Received: 29 April 1996/Accepted: 10 June 1996  相似文献   

8.
Ammonites from the Riasanites rjasanensis Zone (Ryazanian Stage of the Russian Platform) of the family Neocomitidae are considered. The new species Mazenoticeras robustum sp. nov. and M. ceccai sp. nov. are described. Other members of this genus and of the genera Malbosiceras and Pomeliceras are identified in open nomenclature.  相似文献   

9.
It is commonly accepted that dasyurids (Marsupialia: Dasyuridae) radiated in the late Miocene or early Pliocene in response to a drying trend in Australia's climate as evidenced from the high diversity of dasyurids from modern arid environments compared with Miocene rainforest assemblages. However, mid‐Pleistocene dasyurid assemblages from cave deposits at Mt Etna, Queensland are more diverse than any previously known from rainforest habitats. New taxa will be described elsewhere, but include three new genera as well as new species of Dasyurus, Antechinus and Phascogale. Comparison of dasyurids from Mt Etna sites that are interpreted as rainforest palaeoenvironments with fossil and extant assemblages indicate that they are at least as diverse as those from modern arid environments. Thus Neogene diversification of dasyurids occurred in both arid and rainforest habitats, but only the former survived continuing aridification. Hence, aridification cannot be invoked for the diversification of all dasyurid lineages.  相似文献   

10.
Abstract. Sponges can serve as hosts to invertebrate assemblages that live and reproduce within them. Sponges also constitute a major part of the benthic epifaunal community on the continental shelf of the southeastern United States; however, little is known about these sponges and the assemblages they harbor. In this study, the associated fauna from a variety of sponges and one species of tunicate collected by submersible from the continental shelf and slope of the southeastern United States at depths in the range 18–875 m were examined. Seventeen sponges, comprising eight species (Ircinia campana, Topsentia sp., Geodia sp., Characella sp., Erylus sp., Apylsina archeri, Cliona sp., and Pheronema carpenteri), and three tunicate colonies (Didemnidae) were fully dissected and all associated organisms were identified and counted. Additionally, the sponges Pheronema annae (951 m) and P. carpenteri (770 m) represent new records for the region. The diversity (H′) and density of associates varied considerably among hosts; the densities of associates ranged 0.4–11,684 per 1 L of host volume. Polychaete worms were the most common organisms found, with one species, Haplosyllis spongicola, being especially abundant in I. campana, Topsentia sp., and Cliona sp. The amphipods Ericthonius punctatus and Leucothoe cf. spinicarpa, as well as decapods such as snapping shrimp (Synalpheus sp.) and crabs (e.g., Pilumnus floridana, Micropanope urinator), were also common. The number of symbiont taxa did not significantly increase as the sponge size increased. However, weak positive trends were found between the diversity of associates and increasing canal diameter. Sponges and tunicates were judged to represent legitimate ecological communities harboring a complete food web as well as gravid and juvenile individuals.  相似文献   

11.
Two gastropod assemblages from the Carnian (Upper Triassic) Raibl Beds of the Mežica region (Karavanke Mountains, Slovenia) are described. The almost monospecific, older assemblage from Mežica Mine was found as a thin shell pavement in the clastic sequence. This association apparently originated during a period of reduced sedimentation. The younger assemblage from Helena Creek was found at the upper surface of an oolitic and oncoidal limestone and represents a more diversified fauna of a crinoid/coelenterate/polychaete meadow. Together, both assemblages contain 11 gastropod species. Five of them are left in open nomenclature, two are known from other localities in the Alps, and the remaining four are new. The new species are Sloeudaronia karavankensis (Skeneidae), Helenostylina mezicaensis (Coelostylinidae), Ampezzopleura slovenica and Striazyga crnaensis (Zygopleuridae). Two new genera, Sloeudaronia (Skeneidae) and Helenostylina (Coelostylinidae), are described.An erratum to this article can be found at  相似文献   

12.
13.
In the Early Carboniferous-Bashkirian the most diverse ammonoid assemblages were associated with deep-water settings of the outer shelf and the carbonate platform slope. At the end of the Early Bashkirian, ammonoid assemblages of basins of the eastern slope of the South Urals were associated with shallow-water settings and bioherm buildups, which probably contributed to their endemism. New species of the genera Neogoniatites, Schartymites, and Stenoglaphyrites are described from localities of the eastern slope of the South Urals.  相似文献   

14.
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   

15.
Abstract: The mid‐Cretaceous bivalve Goshoraia Tamura, 1977, endemic to Japan, is an early example of shallow‐marine siphonate bivalves of the family Veneridae Rafinesque, 1815. Three species, including one new, are here described: Goshoraia minor Tashiro and Kozai, 1989 (Aptian), G. crenulata (Matsumoto, 1938; Albian–lower Cenomanian) and G. maedai sp. nov. (middle to ?upper Cenomanian). The habitats of Goshoraia have been extensively compared with those of common Cretaceous, nonsiphonate burrowers, such as trigoniids, which range from tidal flat and shoreface to shelf environments. Depth of burial, which can be estimated from the extent of the pallial sinus, increases from the ancestral G. minor to its descendants G. crenulata and G. maedai sp. nov., documenting that the ability to burrow within this genus improved in time. These morphological and palaeoecological changes may be related to the Mesozoic marine revolution during the mid‐Cretaceous.  相似文献   

16.
E. I. Schornikov 《Hydrobiologia》2005,538(1-3):193-215
Deep-sea Pedicythere species which had been earlier considered as pan-abyssal in distribution are shown to be composite species including similar, but separate species in the Pacific, Indian and Atlantic oceans. Morphology and distribution of Pedicythere are analysed. A key to well-described Cenozoic species and forms in open nomenclature which are referred to Pedicythere is presented, together with an annotated checklist of species. Five new species of Pedicythere are described from the South China Sea: P. hirundo sp. nov., P. gibbera sp. nov., P. dentata sp. nov., P. arator sp. nov. and P. nivea sp. nov.  相似文献   

17.
Extensive sampling of several Barremian and Albian–Cenomanian levels across the Aguilón, Oliete and Aliaga subbasins of the Iberian Basin, north‐east Spain, yielded abundant material of new or so far poorly known neoselachians. The faunas consist of 16 different species, five of which represent new species and two new genera: Cantioscyllium brachyplicatum sp. nov. , Platypterix venustulus gen. et sp. nov. , Ptychotrygon pustulata sp. nov. , Ptychotrygon striata sp. nov. and Iberotrygon plagiolophus gen. et sp. nov. In addition, teeth of Heterodontus cf. H. carerens, Lamniformes indet., Pteroscyllium sp., Scyliorhinidae indet., Rhinobatos sp., Spathobatis sp., Belemnobatis sp., Ptychotrygon geyeri, Ptychotrygon sp. and Celtipristis herreroi are described. The new family Ptychotrygonidae is defined. The localities comprise palaeoenvironments ranging from lacustrine and shallow lake to open marine settings. Neoselachians are almost completely absent from continental settings in the Barremian, as a result of prevailing freshwater conditions, but became more abundant in marine strata. The Albian–Cenomanian selachian assemblage is the most profuse and diverse of the three assemblages studied. It is dominated by small, benthic and near‐coastal taxa, for instance Cantioscyllium and Ptychotrygon, and contains several new species, including an endemic batoid, Iberotrygon plagiolophus gen. et sp. nov. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 155 , 316–347.  相似文献   

18.
Olga L. Kossovaya   《Palaeoworld》2009,18(2-3):136-151
Recent investigations in the Urals and East-European Platform as well as study of corals collections from South Primorye (Russian Far East) and South-Eastern Pamirs have been undertaken. Antitropical rugose associations include taxa that are bounded in their distribution by the temperate zones of the Boreal and Perigondwanan realms. They occur sporadically in tropical latitudes but never form abundant and diverse communities. Antitropical associations are represented by the so-called ‘Cyathaxonia fauna’ (sensu lato), predominating in two selected stratigraphic intervals. The abrupt change of taxonomic composition from colonial to ‘Cyathaxonia fauna’ allows the separation of two assemblages: (i) mid Artinskian–Kungurian and (ii) Roadian–Wordian. The key regions for comparison are the Urals (mid Artinskian–Kungurian), Spitsbergen (Kungurian–Wordian), East-European Platform (Roadian), Texas (mid Artinskian–Kungurian), South Primorye (Wordian–Capitanian), South-Eastern Pamirs (Upper Artinskian), and the Sverdrup Basin (Wordian). The Late Artinskian fauna of the South-Eastern Pamirs and Wordian faunas of South Primorye bear features of mixed assemblages. A few models of the origination of antitropical assemblages are acceptable: (i) the convergent parallel evolution of Lophophyllidium in the Northern Hemisphere and Southern Hemisphere, (ii) a similar evolution trend developed in parallel in three geographically distant regions: Verbeekiella, Pseudowannerophyllum, and “Pseudoverbeekiella”, and (iii) immigration of some species within temperate zones caused by current circulation changes both in the Northern and Southern Hemispheres, as well as northward spreading of terranes in the Perigondwanan Realm.  相似文献   

19.
Bivalves have been found in unique benthic assemblages associated with active methane seeps and mounds along the western and southern margins of the Svalbard shelf (75–79°N) at 350–380?m depth. Among the samples collected were a number of shells of Thyasiridae that are distinct from any species previously described. Here we describe one new genus Rhacothyas gen. nov. and two new species Thyasira capitanea sp. nov. and Rhacothyas kolgae sp. nov., including their distinguishing characteristics and the environmental setting where they were found. Thyasira capitanea sp. nov. is large compared with many other thyasirids, has an equilateral shell and demarcated zones on the median and anterior areas along with a distinct posterior sulcus. Rhacothyas kolgae sp. nov. is unique among other thyasirid genera and species regarding its characteristic outline, sunken lunule, lack of submarginal sulcus and wrinkled surface. Furthermore, we discuss their present occurrence in the context of the glaciomarine history of the Svalbard margin. We posit that these new species, after the deglaciation of the Barents Sea Ice Sheet, may have originated from other chemosynthetic or reducing environments along the Atlantic shelf margin or the southern Barents Sea shelf by following the net transport of the North Atlantic Current rather than having evolved in situ.

http://zoobank.org/urn:lsid:zoobank.org:pub:0F3DCFD6-05C9-4E76-803E-655ACD3AF335  相似文献   


20.
Two new genera, Fulvoscirtes n.gen. and Acanthoscirtes n.gen. , are established within the subtribe Karniellina of Conocephalini. Fulvoscirtes is based on Xiphidion kilimandjaricum Sjöstedt, 1909 and Acanthoscirtes on Phlesirtes kevani Chopard from northern Kenya. The majority of Fulvoscirtes spp. are confined to open grasslands in the submontane zone of mountains. Fulvoscirtes contains eight species, seven of which are newly described in this paper. Three species and one subspecies occur on Mt Kilimanjaro. These are F. kilimandjaricum (Sjöstedt) constricted to the southern slopes, F. legumishera n.sp. confined to the northern side and F. sylvaticus n.sp. occurring on the western side of Kilimanjaro and on the eastern slopes of Mt Meru. Fulvoscirtes fulvus n.sp. is divided into two subspecies, F. fulvus fulvus n.ssp. found in the submontane zone of east Kilimanjaro and F. fulvus parensis n.ssp. in submontane to montane localities of the North and South Pare mountains. Fulvoscirtes fulvotaitensis n.sp. occurs in the Taita Hills of southern Kenya. Fulvoscirtes viridis n.sp. is described from savannah habitats between Mts Longido and Meru. Fulvoscirtes laticercus n.sp. is found in the Kenyan highlands, while the most southerly occurring species, Fulvoscirtes manyara n.sp. , is found on Mt Hanang and the Mbulu highlands of northwestern Tanzania. Acanthoscirtes contains three species, of which A. albostriatus n.sp. is described newly from savannah habitas of eastern Kilimanjaro. Information is given on the ecology and the acoustic behaviour of some of the species together with keys to the genera of the Karniellina and the species of Fulvoscirtes and Acanthoscirtes. The genera of Karniellina probably evolved at a time when grasslands spread in East Africa due to an increasing aridification of the climate. The earliest lineage, the genus Karniella, is adapted to more forested habitats while the majority of the genera of Karniellina prefer open grasslands. Major splits within Karniellina probably occurred with the emergence of savannah grasslands due to the ongoing fragmentation of forest habitats several millions years ago, but most species within the genera are geologically young, their radiation being boosted by climatic fluctuations of the past 1–2 Ma.  相似文献   

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