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Recent Submissions

  • Vema's Brachiopoda (Recent)

    Cooper, G. (1973)
    G. Arthur Cooper. Vema's Brachiopods (Recent). Smithsonian Contributions to Paleobiology, number 17, 51 pages, 5 figures, 9„plates, 1973.—Brachiopods dredged on the worldwide exploratory cruises of R/V Vema, of the Lamont-Doherty Geological Observatory of Columbia University, are important in expanding knowledge of brachiopod distribution and taxonomy. Thirty-two species are identified, of which six are new. Twenty-one genera are represented, one of which is new. The species of five genera and the genera of two lots could not be determined. The majority of the brachiopods were taken from waters deeper than 100 fathoms. One specimen of Abyssothyris was dredged from the greatest depth (6179 meters=20,267 feet) from which a brachiopod has been taken.
  • Unveiling the submarine landscape of the Namuncurá Marine Protected Area, Burdwood Bank, SW Atlantic Ocean

    Schejter, L.; Martin, J.; Lovrich, G. (2017)
    In this contribution we provide the first images of the submarine landscape of the Namuncurá Marine Protected Area, Burdwood Bank, at the SW Atlantic Ocean. This noninvasive approach revealed and offered a complementary view of the seafloor and its fauna, only previously reported from trawl catches.
  • Transport and variability of the Antarctic Circumpolar Current in Drake Passage

    Cunningham, S.; Alderson, S.; King, B.; Brandon, M. (2003)
    1] The baroclinic transport of the Antarctic Circumpolar Current (ACC) above 3000 m through Drake Passage is 107.3 ± 10.4 Sv and has been steady between 1975 and 2000. For six hydrographic sections (1993–2000) along the World Ocean Circulation Experiment (WOCE) line SR1b, the baroclinic transport relative to the deepest common level is 136.7 ± 7.8 Sv. The ACC transport is carried in two jets, the Subantarctic Front 53 ± 10 Sv and the Polar Front (PF) 57.5 ± 5.7 Sv. Southward of the ACC the Southern Antarctic Circumpolar Current transports 9.3 ± 2.4 Sv. We observe the PF at two latitudes separated by 90 km. This bimodal distribution is related to changes in the circulation and properties of Antarctic Bottom Water. Three realizations of the instantaneous velocity field were obtained with lowered ADCPs. From these observations we obtain near‐bottom reference velocities for transport calculations. Net transport due to these reference velocities ranges from −28 to 43 Sv, consistent with previous estimates of variability. The transport in density layers shows systematic variations due to seasonal heating in near‐surface layers. Volume transport‐weighted mean temperatures vary by 0.40°C from spring to summer; a seasonal variation in heat flux of about 0.22 PW. Finally, we review a series of papers from the International Southern Ocean Studies Program. The average yearlong absolute transport is 134 Sv, and the standard deviation of the average is 11.2 Sv; the error of the average transport is 15 to 27 Sv. We emphasize that baroclinic variability is an important contribution to net variability in the ACC.
  • Tintinnids (Cilophora) and other net microzooplankton (>30um) in South-western Atlantic Shelf Break Waters

    Thompson, G.; Alder, V.; Boltovskoy, D. (2001)
    Proportions of foraminifers, tintinnids, polycystine radiolarians, pteropods and crustacean larval stages were estimated in a collection of 76 vertically stratified (0 – 100 m) 30 µm net microplankton samples from 16 stations along the Argentine shelf-slope (around 200 m isobath – between 40 and 56° S), covered on 13 – 18 November 1996. Tintinnids were identified to species. Relative abundances of the microzooplankton assessed and chlorophyll a values allow to define two contrasting groups of stations: ‘deep’ and ‘shallow’. The former, located in pelagic, purely subantarctic Malvinas Current waters, hosted higher proportions of foraminifers and lower proportions of tintinnids, as well as less chlorophyll a (all differences were significant at the 0.1 % level). ‘Shallow’ stations were located in the area of the thermohaline front where the Patagonian Current comes in contact with the Malvinas Current, and were generally characterized by higher chlorophyll a levels (up to 3.7 µg Chl a · l–1). The distribution of tintinnid species, on the other hand, allowed no discrimination between these two areas, although some of the dominant forms showed much higher relative abundances in one of the two groups of stations. Twenty-six tintinnid taxa were recorded, yet only 6 accounted for 95 % of the specimens identified. Tintinnid taxocoenoses were characterized by a few abundant species and many rare ones. Numbers of tintinnid species and specific diversity did not differ noticeably with depth and latitude. Cape Horn Current waters were detected in the area by the presence of expatriated organisms presumably originating at mid-latitudes in the South Pacific Ocean.
  • Tintininos (Ciliophora - 5ubordem Tintinnina) de águas subantárticas e antárticas entre a Argentina e a Península Antártica (35°5-62°5) (Novembro de 1992)

    Fernandes, L. (1999)
    A taxonomic survey on the tintinnids (Suborder Tintinnina) sampled from surface waters along a latitudinal transect between Argentine and Antarctic Peninsula (35 degree S - 62 degree S) was made in November 1992. Twenty two taxa were determined, belonging to the genera Acanthostomella, Amphorides, Codonellopsis, Coxliella, Cymatocylis, Favella Helicostomella, Laackmaniella, Protorhabdonella, Stylicauda and Tintinnopsis. The species Acanthostomella norvegica, Amphorides quadrilineata, Codonellopsis gaussii, Cymatocylis antarctica, C. convalaria and Tintinnopsis bacillaria were abundant in the samples. The species C. antarctica dominated in most of the stations sampled in subantarctic waters, while C. convalaria and Codonellopsis gaussi were abundant in antarctic waters. The genera Favella, Helicostomella, Stylicauda and the species Tintinnopsis gracilis were only recorded in waters under the influence of the La Plata river. For all species, were provided descriptions, measurements and drawings, as well as comments on the taxonomy.
  • The subantarctic and polar fronts in relation to deep water masses through the southwestern Atlantic

    Peterson, R.; Whitworth, T. (1989)
    The two principal fronts within the Antarctic Circumpolar Current (ACC), the Subantarctic Front (SAF) and the Polar Front (PF), are investigated with respect to their spatial patterns and relations to deep water masses from the northern Drake Passage to the western and southern Argentine Basin. Observations from four recent cruises in adjoining and overlapping regions are supplemented with satellite infrared imagery and trajectories from surface drifters. East of Drake Passage, the width of the Polar Frontal Zone (PFZ) increases rapidly when the SAF turns sharply northward as a part of the Falkland (Malvinas) Current, while the PF remains oriented mainly toward the northeast. Found within this region of the PFZ are mesoscale eddies, the upper layers of which consist of Subantarctic Mode Water from the Pacific. The contrasts in upper layer water properties that identify the SAF can be traced the entire length of the Falkland Current to the Brazil‐Falkland confluence zone and then southward to the southern Argentine Basin. There the SAF turns eastward and later, but perhaps not always, merges with the PF north of Ewing Bank to form a single, intense current core strongly influenced by bottom topography. At times this eastward current loops southward through a gap in the Falkland Ridge into the Georgia Basin, thereby supplying relatively warm and salty Subantarctic water to the Antarctic Zone. East of the gap, the two fronts become separated and are once again distinct features in the vicinity of the Islas Orcadas Rise. At depth, within Drake Passage and the western Scotia Sea, the SAF and PF are not lateral boundaries between distinct water masses, but are instead identified by enhanced vertical displacements of property isopleths. With the northward turn of the SAF east of Drake Passage, a thick layer of Circumpolar Deep Water (CDW) is advected over the Falkland Plateau into the Argentine Basin. There it is joined by waters entering the Argentine Basin via a deep spreading route through the Georgia Basin: denser CDW, deep water from the Weddell Sea, and episodically, deep water from the southeastern Pacific Ocean. Together, these waters form a northward flow off the Patagonian shelf that extends from the sea surface to the bottom, most of which turns back toward the south with the Falkland Current return. Also flowing south, along the seaward side of the Falkland Current return well away from the western boundary, is the main core of North Atlantic Deep Water (NADW). Detatched masses of NADW are observed within the CDW at the western boundary as well as within the ACC south of the SAF in the south central Argentine Basin.
  • The Magellan-Antarctic connection: links and frontiers at southern high latitudes. Summary review

    Arntz, W. (2005)
    Eight years of research in the Magellan regionand Antarctic marine ecosystems have passed sincethe first IBMANT Symposium held in Punta Arenasin 1997 (Arntz and Ríos, 1999). Considerable bio-geographic and biodiversity work, supported byphysiological and molecular genetic approaches, hasbeen published during this time, especially in theAntarctic, much of it in the framework of SCAR’sEASIZ and EVOLANTA programmes (Di Prisco etal., 1998; Davison et al., 2000; Arntz and Clarke,2002; Huiskes et al., 2003; Clarke et al., subm.), andrecently by research extending into the deep sea(Brandt and Hilbig, 2004). Marine science in theMagellan region, which had received importantstimuli from the “Victor Hensen” and “Vidal Gor-maz” campaigns in the previous period (Arntz andGorny, 1996; CONA, 1999 a, b), was advancedrather by individual approaches such as the decapodand fish work carried out by the CADIC and col-leagues from Ushuaia (e.g. Lovrich et al., 2003; Fer-nández et al., 2000)but also received further inputfrom CIMAR Fiordo cruises nos. 3, 4, and 7between 1997 and 2001, and the “LAMPOS” cruiseof RV “Polarstern” along the Scotia Arc (CONA,1999 a, b; Arntz and Brey, 2003).
  • The families carditidae and condylocardiidae in the magellan and perú-chile provinces (bivalvia: Carditoidea)

    Güller, M.; Zelaya, D. (2013)
    Based on the study of available types and extant collections, this paper provides a systematic revision of the living species of Carditoidea occurring in the Magellan and Perú-Chile Provinces. Out of the 19 nominal species reported for the area, eight species are recognized as valid: Cyclocardia compressa, C. spurca, C. thouarsii, C. velutina, Carditella naviformis,C. semen, C. tegulata and Carditopsis flabellum. Other eight nominal species are regarded as synonyms: Cardita magel­lanica of Cyclocardia velutina; Carditella pallida of C. tegulata; Cardita australis and Actinobolus philippi of Carditella naviformis; Cardium pygmaeum of Carditella semen; Cardita paeteliana of Cyclocardia spurca; Carditella pallida duo­decimcostata of Carditopsis flabellum; and Cardita congelascens of Cyclocardia thouarsii. Furthermore, Cardita malvi­nae and Cardium parvulum are nomina dubia, and the occurrence of Carditella exulata in Magellanic waters is doubtful.
  • The boundary currents in the western Argentine Basin

    Peterson, R. (1992)
    A quasi-synoptic hydrographic data set enclosing the Brazil-Falkland (Malvinas) Confluence Zone is used to investigate the absolute geostrophic volume transports of the western boundary currents in the region. Water mass characteristics provide a basis for adjusting geostrophic shears near the continental margin at 38°S, and the depth-integrated southward transport there, comprised of the Brazil Current and deep boundary flow, is estimated to be 68 Sv (1 Sv = 106 m3 s−1). Of this, 26 Sv are thermocline water, 18 Sv are Antarctic Intermediate Water, and 24 Sv are deep waters of circumpolar and North Atlantic origin. Assuming the bottom flow is parallel to the steep bathymetry at the western boundary of the Argentine Basin, a geostrophic transport of 143 Sv is found to move seaward across the 4600-m isobath between the latitudes of 38° and 46°S. Top-to-bottom northward transports in the region of the Falkland Current are then solved as residual quantities from mass balances for enclosed areas. The likelihood of significant northward bottom velocities in deep western boundary currents there, combined with there being no apparent reversals within the water column in the direction of flow, makes such a procedure necessary. The resulting estimates for the depth-integrated northward transports in the Falkland Current region are 75 Sv at 42°S and 88 Sv at 46°S. Approximately 60 and 70 Sv, respectively are contained in the upper 2000 m as a direct extension of the northern Antarctic Circumpolar Current, while 34 and 40 Sv are contained in the density range of surface and intermediate waters. The northward transports in layers beneath the 2000-m level belong to the deep western boundary currents of the southern Argentine Basin. These numbers for the Falkland Current region are much larger than the 10–20 Sv values typically found in the literature, but they are consistent with other information such as the volume transport in the upper 2000 m of the northern Antarctic Circumpolar Current in Drake Passage, velocities of surface drifters in the Falkland Current, and the full-depth circulation in the interior of the Argentine Basin.
  • The benthic deep-water siphonophore Rhodalia miranda and other coelenterates in the south-west Atlantic: ecological and oceanographical implications

    Riemann-ztirneck, K. (1991)
    The benthic deep-water siphonophore Rhodalia miranda was collected for the first time in 1876 by H.M.S. ‘Challenger’ off the Rio de la Plata estuary beneath the Subtropical Convergence at about 1000 m depth. Rhodalia was reported again about 100 years later from certain distant localities in the subantarctic region of the south-west Atlantic. Hydrographic and topographic features that may be involved in creating this peculiar distribution pattern are discussed together with a likely mode of dispersal of benthic coelenterates. The disjunct distribution of Rhodalia and other benthos of the upper Argentine Slope suggests the subsurface oceanographic régime to be quite different from what we know of the surface layers.

    Wysokinski, A. (1974)
    The combined biological and fisheries investigations carried out from the Polish research vessel ,,Profesor Siedlecki" on the Argentine shelf resulted, among other things, in esta­ blishing the large-size hake occurrence that had not been observed before. The fish meristic characters, presented herein, correspond with those of Merluccius polylepis Gins­ burg, 1954 known from the southern coast of Chile. The distribution limit for both the Argentine hakes, M.hubbsi and M.polylepis described is set in the Atlantic Ocean between 47 and 48°S. Taxonomically, Mpolylepis to the greatest extent resembles M.australis and M.paradoxus.
  • Species richness of marine Bryozoa in the continental shelf and slope off Argentina (south‐west Atlantic)

    Lopez Gappa, J. (2000)
    A total of 246 marine bryozoan species was recorded within an area of the south-west Atlantic between 35° and 56°S, and between the coast of Argentina and 50°W. The distribution pattern of benthic stations surveyed during the most important cruises in the area shows that the sampling effort has been biased towards southern shelf areas off Santa Cruz and Tierra del Fuego, as well as around the Malvinas (Falkland) islands. The littoral zone, Patagonian gulfs and the continental shelf off Chubut, Río Negro and Buenos Aires state received less attention, and should be surveyed more intensively in the future. Only 2% of the species can be regarded as non-indigenous, all of them inhabiting biofouling communities in harbour environments. With the exception of some thoroughly surveyed localities, the number of species recorded for different areas of the coast, shelf and slope is estimated to be just a small fraction of the actual number of species present. A distinct diversity gradient was found, with species-rich stations located only in the southern shelf. Highest diversity occurred in shelf areas dominated by coarse sediments, and along a high-productivity shelf-break front. A remarkable decrease in species richness was found in inner and middle shelf areas off Chubut, Río Negro and Buenos Aires state. This pattern may be related to the Pacific origin of the Magellanic fauna, since the diversity of bryozoans is higher in the Pacific than in the Atlantic Ocean. The trend of species richness is, however, overemphasized by the fact that the least diverse faunistic assemblage occurs in areas where surveys have been relatively less frequent. An up-to-date checklist of species recorded for the study area is included.
  • Sedimentación marina profunda en el margen continental argentino: Revisión y estado del conocimiento

    Violante, R.; Cavallotto, J.; Bozzano, G.; Spoltore, D. (2017)
    El Margen Continental Argentino (MCA) ocupa un lugar privilegiado en el océa no mundial por su contexto oceanográfico altamente dinámico asociado a la circu- lación global, que favorece el desarrollo de extensas capas nefeloides con gran cantidad de sedimentos en suspensión, así como una alta energía de los agentes de erosión y transporte que son capaces de movilizar sedimentos en el fondo marino. Estas condiciones coadyuvan a la ocurrencia de procesos sedimentarios profundos de gran magnitud y complejidad. El margen comenzó a ser estudiado a partir de mediados del siglo XX. El conocimiento que se tenía por ese entonces, que acompañaba a las hipótesis de la época a nivel internacional, señalaba que los procesos sedimentarios dominantes en las regiones profundas del talud y emersión eran los gravitacionales y pelágicos. Se desconocía la influencia de las corrientes de fondo asociadas a la estructura oceanográfica de carácter termohalina, al menos en magnitud importante como para ejercer un efecto modelador significativo sobre el suelo marino. Estudios realizados en las últimas dos décadas alertaron sobre la ocurrencia de procesos sedimentarios asociados a corrientes profundas paralelas al margen capaces de construir cuerpos contorníticos (drifts) elongados en el sentido de circulación de las corrientes. El redescubrimiento de estos procesos llevó a cambiar substancialmente los mapas del lecho marino. Estos nuevos conceptos no solamente marcaron un significativo avance en el campo de la Geología Marina, sino que permitieron comprender que ésta no podía ser considerada e interpretada sin el apoyo de la Oceanografía Física. EnEn base a la interrelación entre los tres procesos sedimentarios básicos que ocurren en los fondos marinos (longitudinales, gravitacionales y pelágicos), el MCA es subdividido regionalmente, de norte a sur, en seis regiones, cada una con sus rasgos morfosedimentarios propios, de acuerdo fundamentalmente a las características que presentan las formas resultantes de los procesos dominantes, que son los contorníticos y gravitacionales. Regionalmente, en el sector de margen pasivo los cuerpos contorníticos son continuos a lo largo de 1600 km, denotando la gran extensión sobre la cual actúan las corrientes de fondo; su magnitud (extensión y espesores) disminuyen progresivamente de sur a norte, debido a factores múltiples como la decreciente dinámica de aquellas corrientes y la interacción con procesos gravitacionales. No obstante, vuelven a adquirir grandes dimensiones hacia el margen de Brasil en un contexto oceanográfico diferente al del margen argentino. En cambio, en los sectores de márgenes transcurrente y mixto adyacentes al sector sur patagónico y Arco de Scotia, los cuerpos contorníticos son más reducidos en tamaño (pocas centenas de km de extensión) y en general de menores espesores, dado que se vinculan a sectores localizados en fosas, canales, taludes de extensión limitada, y pasajes entre altos estructurales y elevaciones del fondo.
  • Sediment transport and distribution in the Argentine Basin. 5. Sedimentary structure of the Argentine margin, basin, and related provinces

    Ewing, M.; Lonardi, A. (1971)
    SEDIMENT TRANSPORT AND DISTRIBUTION IN THE ARGENTINE BASIN. 4. BATHYMETRY OF THE CONTINENTAL MARGIN, ARGENTINE BASIN AND OTHER RELATED PROVINCES. CANYONS AND SOURCES OF SEDIMENTS1" By ALBERTO G. LONARDI* and MAURICE EWING ABSTRACT More than 152,500 km of precision sounding lines collected mostly by Lamont Geological Observatory up to February 1967 have been complemented with spaced soundings to construct a chart of the detailed submarine topography of the western South Atlantic, for the area located between 27°S and 57°S, and 28°W and 76°W. Seismic reflection data have been used to correlate the sediment distribution pattern and associated basement rock with the resulting configuration of the sea floor. On the basis of this comparative study the main physiographic provinces have been represented, defined and briefly described. Particular attention is given to the morphology of the Argentine continental margin and to its relation with other provinces. This study reveals that the Argentine Continental Slope and Rise are dissected by 70 submarine canyons, two of which, Ameghino Transverse Canyon and Almirante Brown Transverse Can- yon, trend parallel to the regional isohaths. The greatest regional erosion is found on the Continental Slope between 42°S and 46°S (Ameghino canyon system). Many of the 30 canyons identified in this region are tributaries of the Ameghino and Almirante Brown Transverse Canyons. Several submarine canyons are grouped off the Rio de la Plata, the major Argentine river, but are not as deeply incised as those of the Ameghino system. Topography of the group suggests that the axis of discharge of the Rio de la Plata during glacial stages was more to the south than at present and that the position of the river probably shifted with time. The genesis of all canyons studied along the continental margin can be reasonably related to Pleistocene glacial outwash drainages. The Polonio Fault, located off Uruguay, is the only evidence of major recent tectonism along the margin. Newly identified physiographic provinces include: the Lower Plateau off Brazil, the Malvinas Outer Basin, the Rio Grande Abyssal Plain, the North Georgia Abyssal Plain, the Eastern Enclosed Abyssal Plain, sedimentary ridges of regional extent and area covered by the giant ripples in the Argentine Oceanic Rise, and three major trenches with associated ridges in the Scotia Basin.

    Coelho, P. (1999)
    The genera Eurypodius, Anomalothir and Eucinetops are transferred from subfamily Inachinae, the first one to subfamily Eurypodiinae MacLeay, 1838 and the others to subfamily Anomalopodinae Stimpson, 1871. These genera are represented by the species E. latreillei Guérin, 1828, A. furcilatus (Stimpson, 1871) and E. blakciana Rathbun, respectively.
  • Results of the research cruises of FRV ‘Walther Herwig'to South America. XLVIII. Revision of the South American Zoarcidae (Osteichthyes, Blennioidei) with the description of three new genera and five new species

    Gosztonyi, A. (1977)
    Ergebnisse der Forschungsreisen des FFS ,,Walther Herwig" nach Siidamerika . XLVIII. Revision der südamerikanischen Zoarcidae (Pisces, Blennioidei), mit Be -schreibungen von drei neuen Gattungen und fünf neuen Arten . Die siidamerikanischen Vertreter der Aalmutter-Familie Zoarcidae werden revidiert. Fiin f neue Taxa, drei Gattungen mit ihren Typusarten — Aiakas kreffti, Notolycodes schmidti un d Piedrabuenia ringueleti — sowie zwei weitere neue Arten — Lycenchelys bachmanni und Ophthal-molycus stehmanni — erganzen das bisher bekannte Artenspektrum. Biologische Daten, sowei t vorhanden, und Verbreitungsgebiete werden angegeben . Eine Wertung morphologischer Merkmale, deren taxonomischer Wert in einigen Falle n bisher nicht erkannt worden war, macht eine Parallelentwicklung deutlich zwischen ,,Litorali -sation" der Arten, Verminderung der Kopfporenzahl, Vorwartsverlagerung der Riicken -flossenbasis und starker Asymmetrie der Wirbel . Ein deutlicher Geschlechtsdimorphismus in der Bezahnung wird fur mehrere Arten de r Kiistenzone hier erstmals beschrieben und abgebildet . Ein Bestimmungsschlüssel für alle behandelten Taxa erganzt die Arbeit .
  • Results of the research cruise of FRV Walther Herwing to South America. LXXII. Patagonotothen kreffti sp. n., a new Patagonian notothen from Burdwood Bank, Western South Atlantic (Pisces, Perciformes, Nototheniidae)

    Balushkin, A.; Stehmann, M. (1993)
    Kurzfassung Ergebnisse der Eorschungsreisen des CTS 'Wakber Herwig' nach Sudamerika. LXXII. Patagonotothen kreffti sp. п., eine neue patagonische Nototheniidenart von der Burdwood Bank im Siidwestadantik (Pisces, Perciformes, Nototheniidae). Mit 13 Exemplaren aus Sammlungsbestanden des ZIN und ISH wird Patagonotothen kreffti sip. n. beschrieben, eine neue patagonische Nototheniidenart von der Burdwood Bank im Siidwe-statlantik. Die neue Art steht innerhalb der longipes-Axiengmppe ihrer Gattung P. ramsayi verwandtschaftlich am nachsten, von der sie sich in Farbung, Zahl interorbitaler Schuppen-feihen und einigen morphometrischen Proportionen unterscheidet. Beide Arten besitzen hohere Zahl von Kiemenreusenfortsatzen als die Schwesterarten P. longipes and P. wiltoni. Ein revi-dierter Bestimmungsschlussel fur alle vier Arten der P. longipes-Gmppe wird angeboten. Abstract Patagonotothen kreffti sp. n. is described, based on 13 specimens at ZIN and ISH collected on Burdwood Bank in the Western South Atlantic. Within the longipes-species group of its genus, the new species is most closely related to P. ramsayi, from which it is distinguished by colouration, number of interorbital scale rows, and several proportional morphometries. Both species have higher gill raker counts than the other group members P. longipes and P. wiltoni. A revised key to the four species of the P. longipes-gxowp is provided.
  • Remarks on the taxonomy of the genus Ekleptostylis Stebbing, 1912 (Crustacea: Cumacea: Diastylidae)

    Roccatagliata, D.; Mühlenhaedt-Siegel, U. (2000)
    The adult male and female of Leptostylis vemae Bacescu-Mester, 1967 are described and illustrated. This species is transferred to the genus Ekleptostylis Stebbing, 1912 and the description of Ekleptostylis heardi McLelland and Meyer, 1998 is emended. Both species were found in the Magellan Strait, Beagle Channel, Drake Passage and off Argentina. In addition, E. vemae was found off Uruguay. Diastylis pseudinornata Ledoyer, 1977 from the Kerguelen Islands also is transferred to the genus Ekleptostylis, resulting in a total of four species now in this genus.
  • Redescription of two Antarctic species of Cuspidaria: C. concentrica Thiele, 1912 and C. minima (Egorova, 1993) (Bivalvia, Cuspidariidae).

    Zelaya, D.; Ituarte, C. (2006)
    Cuspidaria concentrica Thiele, 1912 , frequently reported as a synonym of Cuspidaria kerguelensis Smith, 1885, is re-described and revalidated upon the study of new materials from South Georgia Islands; this constitute the first record of its presence in the Scotia Sea. The more elongated shell outline of C. concentrica and the smaller number of elevated lamellar concentric ridges clearly separate it from C. kerguelensis. Cuspidaria minima (Egorova, 1993), a species known from East Antarctica and South Orkneys Islands, is re-described upon material from Elephant Islands. C. minima is characterized by a small shell with a globose disc strikingly separated from the short rostrum, and shell surface with high, lamellated, bent upwards commarginal ridges. Moreover, anatomical data mainly from septal musculature of both species, are given. Furthermore type specimens of Cuspidaria tenella Smith, 1907, Cuspidaria plicata Thiele, 1912 and Cuspidaria infelix Thiele, 1912 are refigured and the reports on the presence of C. kerguelensis in the Scotia Arc Islands are discussed.

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