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New insights into the early diversification of the Ostracoda: Tremadocian ostracods from the Cordillera Oriental, Argentina

100%

Salas M. J., Vaccari N. E.

Acta Palaeontologica Polonica

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2012

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tom 57

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nr 1

New species of ostracods from the Tremadocian in the northwest region of Argentina are described. These are among the earliest well−documented records of ostracods, which shed new light onto the early diversification of the group. The described fauna consists of seven species, five of which are new: Saltite uchuy sp. nov., Saltite kuraq sp. nov., Conchoprimitia? iglesiasi sp. nov., Orechina violetae sp. nov., and Orechina catalinae sp. nov. The fauna consists primarily of soanellids, a non−dimorphic family of palaeocopids, and of binodicopids. One factor leading to diversification of the group in this region may have been the complex configuration of the northwest basin, which had a restricted pattern of circulation. The distribution of the first ostracods is largely restricted to Gondwana and peri−Gondwana regions. Accordingly, it is possible to envision that the origin or at least an important radiation of the group was centred in this region. Both the Soanellidae and the genus Orechina would have originated in Gondwana and would have become widespread later during the Middle Ordovician. The Tremadocian fauna located in Argentina show significant affinities with fauna located in the warm−water setting of the east Gondwana, mainly in Australia and China.

2

Ostracods from the Purbeckian of Central Poland

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Sztejn J.

Acta Palaeontologica Polonica

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1991

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tom 36

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nr 2

The recent stratigraphical and paleontological research in the Jurassic/Cretaceous boundary sequence in central Poland confirmed a validity of the hitherto accepted local ostracod zonation. Six ostracod zones have been compared with the zones distinguished in England, France and Germany. From 51 ostracod species and subspecies recorded in the sequence of superposing marine-brackish and brackish-fresh-water sediments the author describes the following new species and subspecies: Limnocythere biverrucosa, Timiriasevia polonica, Cypridea aleksandrowiensis, C. wandae, C. binodosa polonica, C. dunkeri spinosa, C. granulosa polonica, C. lata polonica, C. obliqua polonica, C. prealta iuvencula and C. tumescens granulosa.

3

Recent benthic Ostracoda from Hornsund, south Spitsbergen, Svalbard Archipelago

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Mackiewicz A.

Polish Polar Research

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2006

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tom 27

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nr 1

71-90

This paper includes a check-list of Recent Svalbard marine ostracods based on published sources and on diploma theses as well as some new studies. This is the first study of this group of crustaceans from Hornsund. A total of 41 species belonging to 12 families were collected at 55 sampling stations from dredged sediments. Seven species are reported for the first time from the Svalbard Archipelago. Polycope orbicularis Sars is the most abundant species in the present fauna. Species compositions of Hornsund and the Liefde- fjorden are seen to have the highest similarity (S = 50.6).

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Recent ostracods from Admiralty Bay, King George Island, West Antarctica

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Majewski W., Olempska E.

Polish Polar Research

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2005

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tom 26

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nr 1

13-36

Ostracods from Admiralty Bay on King George Island (South Shetland Islands) represent 29 podocopid species, belonging to 19 genera, one cladocopid and six myodocopid species. They were recovered from Recent marine and/or glacio-marine sediment samples from water depths of up to 520 m. These ostracods constitute a variable assemblage, which is overall typical for the Antarctic environment. Shallow-water assemblages tend to be more variable in terms of frequencies and species richness than deep-water assemblages. The later are low in numbers and remain relatively high diversities. Overall, no linear relation between ostracod assemblage-composition and environmental features analyzed was recognized.

5

An enigmatic early ? palaeocope ostracode from the Arenig of NW Russia

100%

Tinn O., Meidla T.

Acta Palaeontologica Polonica

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2002

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tom 47

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nr 4

The ostracode Lavachilina evae gen. et sp. nov. is described from the Arenig of Western Russia. Its carapace possesses a unique discontinuous velum, developed at both ends as a narrow spinose ridge. The systematic position of L. evae is uncertain. Its character set shows mostly palaeocope affinities but also some features of leiocopes. L. evae is tentatively assigned to the palaeocope family Oepikellidae, possibly representing an early member of that family. Although L. evae existed contemporaneously with palaeocopes such as Laccochilina, it does not appear to be closely related to these early eurychilinoids.

6

Materiały do znajomości małżoraczków (Ostracoda, Crustacea) wschodniej Polski

84%

Sywula T.

Zeszyty Naukowe Wydziału Biologii i Nauk o Ziemi. Uniwersytet Gdański. Biologia

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1983

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nr 04

7

Małżoraczki (Ostracoda) okolic Otomina na Pojezierzu Kaszubskim

84%

Sywula T., Sell J., Lorenc R.

Zeszyty Naukowe Wydziału Biologii i Nauk o Ziemi. Uniwersytet Gdański. Biologia

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1982

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nr 03

8

Benthic ostracods from the Early-Middle Frasnian transition in the north-western East European Platform, Russia

84%

Evdokimova I. O.

Acta Palaeontologica Polonica

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2006

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tom 51

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nr 4

773-778

Pronounced changes in benthic ostracod associations in the north−west part of the East European Platform, across the Early–Middle Frasnian (Devonian) transition, track a marine transgression event. More than 80 ostracod species belonging to the Eifelian Mega−Assemblage were recorded. Cavellinidae and Acratiidae generally dominate the Early Frasnian Sargaevo Horizon. Middle Frasnian ostracod associations of the Semiluki Horizon are more diverse and are characterised by different dominant both geographically and stratigraphically, resulting from significant palaeo−basin bottom relief and benthic biotope differentiation. The ostracod associations are indicative of very shallow, well oxygenated semi−restricted epeiric environment, with occasional marine influence, alternating with short periods of open shelf conditions. The relative abundance of ostracod species in the different associations, and faunal diversity indices, show considerable variations throughout the Early–Middle Frasnian, and suggest a less restricted position within an intra−platform setting in the Middle Frasnian, relative to a more restricted ostracod habitat in the Early Frasnian. The succession of Early–Middle Frasnian micro−benthic associations within the Main Devonian Field seems to be of a regional scale, and resulted from a marine regression−transgression couplet, corresponding to eustatic cycles IIb–IIc. This was paired with synsedimentary tectonic subsidence in adjacent areas of the north−east East European Platform, progressively improving marine water circulation in the extremely shallow−water shelf seas.

9

Middle Devonian conodont, ostracod and miospore stratigraphy of the Grzegorzowice-Skaly Section, Holy Cross Mountains, Poland

84%

Malec J., Turnau E.

Bulletin of the Polish Academy of Sciences. Earth Sciences

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1997

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tom 45

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nr 1

10

Early Frasnian ostracods from the Arche quarry (Dinant Synclinorium, Belgium) and the Palmatolepis punctata Isotopic Event

67%

Casier J.-G., Olempska E.

Acta Palaeontologica Polonica

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2008

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tom 53

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nr 4

Ostracods from the Arche quarry at Frasnes are analysed. Twenty−seven species are recognised in the Chalon Member and in the very base of the Arche Member of the Moulin Liénaux Formation. Three new species: Scrobicula gracilis, Microcheilinella archensis, and Bairdia (Rectobairdia) chalonensis, and one subspecies Plagionephrodes laqueus praelaqueus, are proposed. The fauna is in the Favulella lecomptei Zone based on metacopid ostracods and belongs to the Eifelian Mega−Assemblage. Ostracods are indicative of a regressive trend from a moderately deep poorly oxygenated marine environment below fair weather wave base to very shallow well oxygenated and agitated environments. Comparison of the ostracod fauna present in the Arche quarry with faunas described from the Frasnes railway section and from the Lion quarry shows that ostracods did not suffer a crisis during the Palmatolepis punctata Conodont Zone and close to the Early–Middle Frasnian boundary.

11

Sexual dimorphism and pore systems in Ordovician ostracodes

67%

Schallreuter R. E. L., Hinz-Schallreuter I. C. U.

Acta Palaeontologica Polonica

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2010

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tom 55

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nr 4

Open antra, a special form of external brood pouches in Ordovician ostracodes suitable for both egg and brood care, are enabled by the associated pore system. Special kinds of radial pores connected with the adventral sculptures are described for the first time. Relationships exist between antral development and lifestyle in that open antra occur in nektobenthic taxa, while closed antra (false brood pouches) are connected with a benthic lifestyle. Taxa, particularly those with open antra, which are morphologically very similar in being non−lobate or non−sulcate, can be distinguished by the construction of the respective antra and the associated pore systems, as exemplified by Levisulculus, Swantina, and Ampletochitina.

12

Ostracods from the Upper Eocene of East Poland

67%

Szczechura J.

Acta Palaeontologica Polonica

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1977

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tom 22

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nr 1

Ostracods of the Upper Éocène epicontinental deposits of east Poland are described. Of the 40 species, referred to 32 genera, Flexus erikae and Pterygocythereis siemienensis are the new ones. Age, palaeogeography and palaeoecology of the studied assemblage are discussed.

13

Ordovician ostracods from East Central Iran

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Ghobadi Pour M., Williams M., Vannier J., Meidla T., Popov L. E.

Acta Palaeontologica Polonica

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2006

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tom 51

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nr 3

Ordovician ostracods are described for the first time from Iran, enhancing the record of this group from the Lower Palaeozoic of the Middle East. The ostracods occur in the Shirgesht Formation, in the east central part of the country, and comprise Ogmoopsis achaemenid sp. nov., Cerninella aryana sp. nov., Ordovizona amyitisae sp. nov., cf. Aechmina? ventadorni, Vogdesella sp., and podocope taxa tentatively identified as species of Longiscula, Pullvillites, and Rectella. These taxa were hitherto unknown from this region. The ostracod−bearing interval is associated with trilobites (Neseuretinus) and brachiopods (Nicolella) that suggest a late Middle Ordovician age. Although the ostracod fauna is small, it demonstrates biogeographical links at genus−level, and possibly at species−level, with the fauna of the late Middle Ordovician Travesout Formation of western France, which also lay in a peri−Gondwanan palaeogeographical setting. It also suggests the potential use of some ostracods as stratigraphical tools for correlating Ordovician rock successions between Europe and the Middle East.

14

An atypical Silurian myodocope ostracod from the Armorican Massif, France

67%

Perrier V.

Acta Palaeontologica Polonica

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2012

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tom 57

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nr 2

A new myodocope ostracod Sineruga insolita gen. et sp. nov. is herein described from the Armorican Massif (France). Sineruga resembles Silurian myodocopes (i.e., bolbozoids and cypridinids) in having anterior features (thinner carapace) possibly related to vision. On the other hand, it resembles entomozoid ostracods in having a bean−shaped outline along with a deep adductorial sulcus and a simple muscle spot, but lacks their characteristic ribbed ornament. The data available suggest that Sineruga insolita was probably an atypical, non−ribbed member of the entomozoids thus indicating that early entomozoids may have had smooth representatives. Comparisons with other Recent and fossils ostracods show that the presence of a rostrum and/or symmetrical vision related carapace features (i.e., indicating lateral eyes) can be used as diagnostic characters for myodocope ostracods. The position and shape of the dorsal connection and to a lesser extent that of the sulcus and the adductorial muscle scar can be used to discriminate the higher groups of Silurian myodocopes (bolbozoids, cypridinids, and entomozoids).

15

Cytheracea (Ostracoda) from the Uppermost Cretaceous and Lowermost Tertiary of Poland

67%

Szczechura J.

Acta Palaeontologica Polonica

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1965

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tom 10

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nr 4

Ostracods of the superfamily Cytheracea from the Uppermost Cretaceous and Lowermost Tertiary of central and north Poland are studied. Of the 63 species and subspecies described, 23 species and 2 subspecies are new. One new genus, Pulaviella, is erected. The variability, ontogenetic development and sexual dimorphism of the described species are analysed. The geographical and stratigraphical distribution of studied Ostracoda and their comparison with those of Foraminifera are discussed.

16

Ostracods and facies of the Early and Middle Frasnian at Devils Gate in Nevada: Relationship to the Alamo Event

67%

Casier J. G., Berra I., Olempska E., Sandberg C., Preat A.

Acta Palaeontologica Polonica

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2006

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tom 51

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nr 4

813-828

In order to document the Alamo Event and to investigate its influence on shallow−marine environments, we undertook a study of ostracods, conodonts, and analysis of the sedimentology of the lower member of the type Devils Gate Limestone. Six major carbonate microfacies (MF1–MF6) ranging from open−marine environments below storm wave base to pre−evaporitic supratidal lagoons were recognized. The sedimentological study detected no important sedimentological changes during the Alamo Event; only an influx of detrital material and lithoclasts indicate that an unusual event had occurred. Ostracods are generally rare or absent in the lower member of the Devils Gate Limestone, and only 2,000 carapaces, valves and fragments were extracted; from these some 26 taxa were identified. Two new species, Voronina? eureka and Serenida dorsoplicata are proposed. The ostracods belong to the Eifelian Mega−Assemblage and their distribution was influenced by strong salinity variations. Because of the rarity and low diversity of ostracods and conodonts in samples collected from the lower part of the lower member of the Devils Gate Limestone it is not adequate to demonstrate conclusively an extinction event close to the Alamo Event Bed. Nevertheless the greater abundance and diversity of ostracods above this bed seems to indicate that the Alamo Event did not result in significant extinction of ostracod taxa in this shallow water setting. The ostracod fauna present in the lower member of the Devils Gate Limestone suggests faunal exchanges between Nevada and the Russian Platform via the Western Canadian platform.

17

Biodiversity evolution through the Permian-Triassic boundary event: Ostracods from the Bükk Mountains, Hungary

67%

Forel M.-B., Crasquin S., Hips K., Kershaw S., Collin P.-Y., Haas J.

Acta Palaeontologica Polonica

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2013

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tom 58

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nr 1

One of the most complete Permian–Triassic boundary sections located in the Bükk Mountains (Hungary) was sampled for ostracod study. Seventy−six species are recognized, belonging to twenty genera. Fifteen new species are described and figured: Acratia? jeanvannieri Forel sp. nov., Acratia nagyvisnyoensis Forel sp. nov., Bairdia anisongae Forel sp. nov., Bairdia davehornei Forel sp. nov., Callicythere? balvanyseptentrioensis Forel sp. nov., Cytherellina? magyarorsza− gensis Forel sp. nov., Eumiraculum desmaresae Forel sp. nov., Hollinella fengqinglaii Crasquin sp. nov., Hungarella gerennavarensis Crasquin sp. nov., Langdaia bullabalvanyensis Crasquin sp. nov., Liuzhinia venninae Forel sp. nov., Liuzhinia bankutensis Forel sp. nov., Microcheilinella egerensis Forel sp. nov., Reviya praecurukensis Forel sp. nov., Shemonaella? olempskaella Forel sp. nov. One species is renamed: Bairdia baudini Crasquin nom. nov. Comparison of the Bálvány North section with the Meishan section (Zhejiang Province, South China), Global Boundary Stratotype Sec− tion and Point (GSSP) of the Permian–Triassic Boundary (PTB), reveals discrepancies linked to the environmental set− ting and particularly to bathymetry. The stratigraphical distribution of all the species is given and diversity variations are discussed. The Bálvány North section exhibits the lowest extinction rate of all PTB sections studied for ostracods analysis associated with a high level of endemism.

18

Ostracods from Permian of Spitsbergen

67%

Olempska E., Blaszyk J.

Polish Polar Research

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1996

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tom 17

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nr 1-2

19

Ostracods and fore-reef sedimentology of the Frasnian-Famennian boundary beds in Kielce [Holy Cross Mountains, Poland]

67%

Casier J. G., Devleeschouwer X., Lethiers F., Preat A., Racki G.

Acta Palaeontologica Polonica

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2002

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tom 47

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nr 2

Four major microfacies have been recognized in the Psie Górki section and the bioclastic content indicates an open marine environment in the photic zone close to an algal shole. Sedimentological studies point to a regressive episode starting close to the Frasnian–Famennian boundary. The regressive microfacies pattern is revealed by the presence of semirestricted algal microbreccias that compose all of the lower part of the Famennian. The regression was accompanied by meteoric water invasion as the sea level fell. Seventy−six ostracod species are recorded. The ostracod assemblage, dominated by podocopids, belongs to the Eifelian ecotype and is indicative of a well−oxygenated marine environment below fair−weather wave base in the Frasnian part of the section, and of shallower environments in the base of the Famennian. No ostracod assemblage characteristic of hypoxic or semi−restricted water conditions has been recorded. The rate of extinction of ostracod species (>70%) close to the Frasnian–Famennian boundary is comparable with that known on the same level in several other sections investigated in the world. Five new ostracod species are proposed by J.−G. Casier and F. Lethiers: Selebratina vellicata, Samarella? minuta, Bairdiocypris ventrorecta, Acratia pentagona, and “Bairdia” psiegorkiensis.

20

Phylogeny, palaeoecology, and invasion of non-marine waters by the late Miocene hemicytherid ostracod Tyrrhenocythere from Lake Pannon

67%

Pipik R.

Acta Palaeontologica Polonica

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2007

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tom 52

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nr 2

Species of the ostracod genus Tyrrhenocythere were found in sediments at the western margin of the Danube Basin, dated as Pannonian zone MN9/MN10 of the late Miocene, together with the euryhaline ostracods Euxinocythere, Loxoconcha, Cyprideis, Hemicytheria, Amplocypris, and Paratethyan Candoninae. Sandy and clayey deposits intercalated with lignite seams, as well as the ostracod assemblages, reflect oscillations of Lake Pannon water level and salinity, from freshwater to pliohaline. Tyrrhenocythere most probably evolved by phyletic transformation from Hemicytheria. The hinge and the central muscle scars of Tyrrhenocythere are plesiomorphic characters and the two genera differ in the arrangement of the marginal pore canals (MPC). The transformation of simple, straight and thin MPC in Hemicytheria to polyfurcate MPC in Tyrrhenocythere can be observed in sympatric and contemporaneous populations in Lake Pannon. On the basis of orna− mentation, T. pezinokensis with heavily calcified valves bearing distinct ornamentation could be a descendent of ribbed and heavily calcified Hemicytheria and possibly represents an extinct lineage, while the lightly calcified T. transitivum sp. nov., T. rastislavi sp. nov., and T.sp. 1, and T. sp. 2 are possibly related to reticulated and punctate Hemicytheria. This model assumes that more than one Hemicytheria lineage transformed their arrangement of MPC, and suggests that Tyrrhenocythere is a polyphyletic genus. After the retreat of Lake Pannon, Tyrrhenocythere species immigrated, together with other ostracod and molluscan fauna, into the Dacian Basin and Eastern Paratethys. Later, in the uppermost Messinian, they colonised the western Mediterranean. Late Miocene and Pliocene Tyrrhenocythere are found in brackish or mixed brackish/freshwater taphocoenoses, but the Pleistocene examples also adapted to freshwater/oligohaline lacus− trine environment (Griffiths et al. 2002: 252). While salinity ranges of Tyrrhenocythere have shifted, toward freshwater since the late Miocene, temperature preference did not change. The mean annual air temperature of the Pannonian (15.6–21.7℃) is close to the temperature preference of living Tyrrhenocythere, with mean annual temperature 12 to 16℃. Two new species, T. rastislavi, and T. transitivum are described.

Ograniczanie wyników

New insights into the early diversification of the Ostracoda: Tremadocian ostracods from the Cordillera Oriental, Argentina

Ostracods from the Purbeckian of Central Poland

Recent benthic Ostracoda from Hornsund, south Spitsbergen, Svalbard Archipelago

Recent ostracods from Admiralty Bay, King George Island, West Antarctica

An enigmatic early ? palaeocope ostracode from the Arenig of NW Russia

Materiały do znajomości małżoraczków (Ostracoda, Crustacea) wschodniej Polski

Małżoraczki (Ostracoda) okolic Otomina na Pojezierzu Kaszubskim

Benthic ostracods from the Early-Middle Frasnian transition in the north-western East European Platform, Russia

Middle Devonian conodont, ostracod and miospore stratigraphy of the Grzegorzowice-Skaly Section, Holy Cross Mountains, Poland

Early Frasnian ostracods from the Arche quarry (Dinant Synclinorium, Belgium) and the Palmatolepis punctata Isotopic Event

Sexual dimorphism and pore systems in Ordovician ostracodes

Ostracods from the Upper Eocene of East Poland

Ordovician ostracods from East Central Iran

An atypical Silurian myodocope ostracod from the Armorican Massif, France

Cytheracea (Ostracoda) from the Uppermost Cretaceous and Lowermost Tertiary of Poland

Ostracods and facies of the Early and Middle Frasnian at Devils Gate in Nevada: Relationship to the Alamo Event

Biodiversity evolution through the Permian-Triassic boundary event: Ostracods from the Bükk Mountains, Hungary

Ostracods from Permian of Spitsbergen

Ostracods and fore-reef sedimentology of the Frasnian-Famennian boundary beds in Kielce [Holy Cross Mountains, Poland]

Phylogeny, palaeoecology, and invasion of non-marine waters by the late Miocene hemicytherid ostracod Tyrrhenocythere from Lake Pannon