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1
CHATTERJEE, TAPAS, IGOR DOVGAL, ROSAURA MAYÉN-ESTRADA e GREGORIO FERNANDEZ-LEBORANS. "A checklist of ciliates (Ciliophora) inhabiting on ostracods (Crustacea, Ostracoda)". Zootaxa 4763, n. 1 (8 aprile 2020): 17–30. http://dx.doi.org/10.11646/zootaxa.4763.1.2.
Testo completoAbstract (sommario):
A compilation of the ciliated species found on freshwater and marine ostracods as epibiont or parasite (endobiont) has been carried out based on published records. The checklist includes the taxonomic position of each species of epibiontic and endobiontic ciliate, the species of basibiont ostracodes, the geographic zones and the bibliographic references where they were recorded. Altogether 7 suctorian, 29 peritrich, one apostome and one scuticociliatid species were listed. Two of recorded suctorian species are possible specific to marine ostracodes, whereas only one, Tokophrya sibirica to freshwater hosts. Fourteen species of peritrichs are likely specific to freshwater ostracodes, while three possible specific to marine ostracode hosts. Other suctorian and peritrich ciliate species were found on a variety of host taxa. One species of scuticociliatid was recorded as endobiont in ostracod.
2
Altinsaçli, Selçuk, Ferda Perçin Paçal e Songül Altinsaçli. "ASSESSMENTS OF ENVIRONMENTAL VARIABLES AFFECTING THE SPATIOTEMPORAL DISTRIBUTION AND HABITAT PREFERENCES OF LIVING OSTRACODA (CRUSTACEA) SPECIES IN THE ENEZ LAGOON COMPLEX (ENEZ-EVROS DELTA, TURKEY)". Ecologica Montenegrina 19 (14 dicembre 2018): 130–51. http://dx.doi.org/10.37828/em.2018.19.14.
Testo completoAbstract (sommario):
The present study analyzed the spatiotemporal changes of Ostracoda fauna in eight coastal lagoons in the Enez-Evros delta (Tuzla Lake 1, Tuzla Lake 2, Tuzla Lake 3, Taz, Işık, Dalyan, Kuvalak, and Taşaltı), located along the northern Aegean Sea coastline of Turkey. Recent ostracod samples collected from the eight lagoons were analyzed, and 16 living ostracod species (belonging to 14 genera) were identified during the sampling periods. The most abundant species were found to be Cyprideis torosa and Loxoconcha elliptica. C. torosa, a cosmopolitan and opportunistic species of Ostracoda, was found in all the studied coastal lagoons. All ostracod species determined in the lagoons were grouped into three assemblages: Group 1: halophilic continental freshwater species (F. fabaeformis, C. vidua, D. stevensoni, E. virens, H. salina, I. biplicata, I. bradyi, L. inopinata, and S. aculeata); Group 2: euryhaline and typical brackish water species (C. torosa and L. elliptica); Group 3: marine (coastal: A. convexa, L. rhomboidea, C. elongata, and X. communis) and brackish (lagoonal: L. lacertosa) water species. These species of Ostracoda were shown to be affected by environmental conditions. Analyses with the physicochemical variables and species (Spearman’s rank correlation coefficient and Canonical Correspondence Analysis) confirmed that ostracod distribution in the Enez lagoons are controlled by seawater–freshwater inputs and by salinity. The purpose of this work is about to present data about of the Enez lagoons, and analyze the diversity of ostracods of them.
3
Hajek-Tadesse, Valentina, e Božo Prtoljan. "Badenian Ostracoda from the Pokupsko area (Banovina, Croatia)". Geologica Carpathica 62, n. 5 (1 ottobre 2011): 447–61. http://dx.doi.org/10.2478/v10096-011-0032-9.
Testo completoAbstract (sommario):
Badenian Ostracoda from the Pokupsko area (Banovina, Croatia)In this paper we present the results of the investigations on the Badenian (Middle Miocene) ostracods from the Pokupsko area. For the first time the presence of Badenian aged sediments in Croatia can be supported by the occurrence of ostracod biozonal markers. Four Badenian ostracod zones are established: Lower Badenian Biozone NO7Acanthocythereis hystrix-Bythocypris lucida, Middle Badenian Biozone NO8Eocytheropteron inflatum-Olimfalunia spinulosa, and the two Upper Badenian Biozones NO9Neomonoceratina laskarevi-Miocyprideis sarmatica elongataand NO10Carinocythereis carinata-Phlyctenophora farkasi.On the basis of the generally accepted paleoecology of selected genera, we identified the following ostracod faunas: shallow-water marine, shallow-water brackish-marine, shallow-water reef, and deep-water marine. The paleontological and trace element analyses suggest that the Pokupsko ostracod fauna lived in shallow (50 m deep), warm, and limpid waters, connected to a deeper sea and occasionally exposed to freshwater inflows.
4
Nazeer, Mohammed Noohu, S. S. Salaj, S. M. Hussain, S. G. Dhanil Dev, D. S. Suresh Babu e N. Mohammed Nishath. "Paleothermometric Inferences Using Elemental Mapping: An Appraisal of Ostracoda Species from Shallow Core Sediment of Bay of Bengal, India". Journal of Geosciences Research 8, n. 1 (1 gennaio 2023): 25–28. http://dx.doi.org/10.56153/g19088-021-0080-17.
Testo completoAbstract (sommario):
Elemental mapping of Ostracoda valves to infer the paleothermometric fluctuations from off-Visakhapatnam, Bay of Bengal is the focus of the present paper. Two Ostracoda species such as Bairdoppilata (Bairdoppilata) alcyonicola and Actinocythereis scutigera were dominant throughout the core. The weight percentages of Mg, Sr, Ba, Fe and Mn in ostracod carapaces were estimated and the ratio with respect to Ca was analyzed to decipher the paleoclimate and oxy-redox conditions. It is observed that trace element accumulation varies with respect to different ostracod species and shell position. Thus, the elemental mapping of the ostracod carapaces by the EDS techniques proved as a primary proxy to decipher the paleotemperature fluctuations in the study area. Keywords: Paleothermometry, Elemental Mapping, Ostracoda, Visakhapatnam, Bay of Bengal
5
PINTO, RICARDO L., CARLOS E. F. ROCHA e KOEN MARTENS. "On the first terrestrial ostracod of the Superfamily Cytheroidea (Crustacea, Ostracoda): description of Intrepidocythere ibipora n. gen. n. sp. from forest leaf litter in São Paulo State, Brazil". Zootaxa 1828, n. 1 (23 luglio 2008): 29. http://dx.doi.org/10.11646/zootaxa.1828.1.3.
Testo completoAbstract (sommario):
Of the three superfamilies of Ostracoda present in fresh water, only the Cytheroidea had thus far no records in terrestrial environments. Here, we report on a new genus and species, Intrepidocythere ibipora n. gen. n. sp., of the ostracod superfamily Cytheroidea, from forest leaf litter in São Paulo State, Brazil. Judging from morphological similarities, this new genus is believed to be closely related to the genus Elpidium. Possible pathways that led to the colonisation of terrestrial habitats are discussed, and an overview is given on the distribution of the known terrestrial ostracod lineages. The present findings strengthen the idea that terrestrial ostracods are more common than previously thought, at least in tropical areas.
6
Kaesler, Roger L., e Michael S. Cormack. "Ostracoda on the Internet". Paleontological Society Papers 9 (novembre 2003): 265–74. http://dx.doi.org/10.1017/s1089332600002242.
Testo completoAbstract (sommario):
Information abounds on the Internet. Information about the Ostracoda is no exception. Here we assess 40 web sites that deal fully or in part with a wide variety of aspects of ostracode biology, paleontology, and ecology.
7
Bergue, Cristianini Trescastro, Renato Pereira Lopes, Felipe Caron, Matias do Nascimento Ritter e Fabio Lameiro Rodrigues. "Paleoecological characterization of ostracods in beachrocks from the Northern sector of the Rio Grande do Sul Coastal Plain, Brazil". Revista Brasileira de Paleontologia 25, n. 4 (31 dicembre 2022): 292–302. http://dx.doi.org/10.4072/rbp.2022.4.04.
Testo completoAbstract (sommario):
A micropaleontological analysis on 15 beachrock samples from the Northern sector of Rio Grande do Sul Coastal Plain (RSCP ), southern Brazil , revealed a relatively diverse and well-preserved ostracod assemblage composed of 16 species , including Cyprideis multidentata Hartmann, Callistocythere nucleoperiscum Whatley et al., Cytheretta punctata Sanguinetti, Caudites ohmerti Coimbra & Ornellas , and Argenticytheretta levipunctata Sanguinetti et al. Eleven ostracod species are left in open nomenclature or tentatively identified . Besides ostracods , some foraminifers , echinoderm spines, and fish remains (teeth) were also recovered ; however , the scarcity of specimens or poor preservation precluded identification at species level. Based on the Ostracoda taxonomic composition it is proposed that the beachrocks characterize environmentally condensed assemblages . This preliminary study reveals the importance and potentiality of micropaleontology for understanding the processes involved in the formation of beachrocks. Keywords: Pelotas Basin, Quaternary, coastal environments, micropaleontology, taphonomy.
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DE ALMEIDA-LIMA, DÉBORA SOARES, ENELISE KATIA PIOVESAN, JULIANA MANSO SAYÃO e FLAVIANA JORGE DE LIMA. "Description and ontogeny of Pattersoncypris minima sp. nov. (Crustacea: Ostracoda), Araripe Basin, Northeast Brazil". Zootaxa 4851, n. 1 (9 settembre 2020): 171–79. http://dx.doi.org/10.11646/zootaxa.4851.1.8.
Testo completoAbstract (sommario):
Representatives of the Class Ostracoda are widely used as tools in applied paleoecological and biostratigraphical studies in all continents. In the Araripe Basin, located in the northeastern of Brazil, the Romualdo Formation is one of the most studied, not only for the preservation but also for the abundance of its fossils. The ostracod genus Pattersoncypris Bate, 1972 is well-represented in this formation and it is the most abundant, which reinforces the importance of its taxonomic study. In this work, Pattersoncypris minima sp. nov. is described for the Romualdo Formation as a contribution to the knowledge on Brazilian Cretaceous non-marine ostracods. Taphonomic aspects are also presented, considering the complete ontogenetic stages of the material.
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Higuti, J., FA Lansac-Tôha, LFM Velho e K. Martens. "Biodiversity of non-marine ostracods (Crustacea, Ostracoda) in the alluvial valley of the upper Paraná River, Brazil". Brazilian Journal of Biology 69, n. 2 suppl (giugno 2009): 661–68. http://dx.doi.org/10.1590/s1519-69842009000300020.
Testo completoAbstract (sommario):
In the present study, we test the relevance of a number of environmental factors on alpha and beta ostracod diversities, at species and family level. Ostracods were sampled from several substrates, including sediment and root systems of various floating aquatic macrophytes, from 48 environments (both lentic and lotic habitats, ranging from the river itself, over connecting channels linking with open lakes, and, finally closed lakes), belonging to four different systems (Paraná, Ivinheima, Baía and Taquaruçu), in the alluvial valley of the Upper Paraná River. The faunistic survey recorded the presence of 54 species of Ostracoda, belonging to the families Cyprididae, Candonidae, Limnocytheridae and Darwinulidae. Various diversity estimators indicated that these recorded levels of specific diversity should be close to true values. Higher values of ostracods species richness (alpha diversity) were observed in the Baía and Ivinheima systems, while lotic habitats were richer than lentic ones. In addition, open lakes appeared to be more affected by the variable 'system' than closed ones, which can to some extend be explained by the putative effects of flood pulse on benthic communities. The two investigated factors have different effects on the four ostracod families. The present study also indicated that there is a large homogeneity within and between systems, as exemplified by the low beta-diversity levels.
10
Ayress, Michael A. "Crescenticythere, a new enigmatic ostracode from the Tertiary of New Zealand". Journal of Paleontology 67, n. 5 (settembre 1993): 905–6. http://dx.doi.org/10.1017/s0022336000037197.
Testo completoAbstract (sommario):
During examination of the large ostracode assemblage collections at the Department of Scientific and Industrial Research, Geology & Geophysics, Lower Hutt, New Zealand, a single specimen of unusual shape was encountered. So unusual is the crescentic outline and infolding of the entire shell periphery that assignment even to a phylum was difficult, and it was only upon scanning electron microscopic study that subcentral muscle scars were clearly observed and these enabled confident identification of the specimen as an ostracode. One specimen is not usually considered sufficient to propose a new taxon; however, in this case there is no doubt that this unique specimen clearly represents a new species, genus, and probably family of Ostracoda. A search for additional specimens from the type unit is underway, but has, as yet, been unsuccessful to find this rare intriguing ostracode. Unlike other unusual ostracodes described from the Southern Hemisphere such as the punciids, this specimen appears to have no similarity with Paleozoic taxa.
11
Salas, María José, Jean Vannier e Mark Williams. "Early Ordovician ostracods from Argentina: their bearing on the origin of binodicope and palaeocope clades". Journal of Paleontology 81, n. 6 (novembre 2007): 1384–95. http://dx.doi.org/10.1666/05-134.1.
Testo completoAbstract (sommario):
New species of ostracods are described from the Tremadoc of the Cordillera Oriental (Argentina). These are among the earliest well-documented records of Ostracoda sensu stricto. The ostracod assemblages are sourced from shallow marine clastics and are dominated by palaeocopes (Eopilla waisfeldaen. sp.,Nanopsis coquenan. sp.), and the binodicopeKimsella luciaen. gen. and sp.EopillaandKimsellashow affinities with species from paleocontinental Gondwana (e.g., Ibero-Armorica, Turkey, Australia, Carnic Alps), butNanopsisis previously known only from paleocontinental Baltica. This study confirms that two of the major clades of Ordovician ostracods, namely the Binodicopa and the Palaeocopa, were already geographically widespread during the late Tremadoc, suggesting a still earlier origin for these groups, possibly from within the Cambrian to Early Ordovician Bradoriida. Evidence from soft-part anatomy indicates that phosphatocopids, the other group hypothesized to be ancestral ostracods, have apomorphies that preclude them as direct ancestors. The origin of ostracods is more likely to be found within the Bradoriida, a probable polyphyletic group that resembles Early Ordovician ostracods in the external sculpture of their bivalved carapace. Evidence from carapace morphology suggests that the ancestors of true ostracods might lie within the bradoriid groups Beyrichonidae and Hipponicharionidae, a hypothesis that can only truly be tested when more evidence from fossilized soft tissues becomes available.
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Szwarc, Agata, e Tadeusz Namiotko. "Biodiversity of Non-Marine Ostracoda (Crustacea) of Botswana: An Annotated Checklist with Notes on Distribution". Water 14, n. 9 (30 aprile 2022): 1441. http://dx.doi.org/10.3390/w14091441.
Testo completoAbstract (sommario):
Botswana constitutes a major gap in our knowledge of the distribution of Ostracoda in the region of Southern Africa, restraining thorough biogeographic interpretations. We combine records from previously published surveys along with our own field collections to provide a collation of living and fossil (Late Pleistocene to Holocene) Ostracoda recorded in Botswana. Our survey yielded 17 species, of which nine species have not been recorded before in the country. Including the present update, 54 species (45 living and nine fossil or subfossil) belonging to 22 genera of five families (with 76% species belonging to the family Cyprididae) are currently reported from Botswana. Yet, 23 taxa are left in open nomenclature, indicating the urgent need for sound systematic studies on harmonizing taxonomy of Southern African ostracods, especially of those inhabiting small temporary waterbodies, considered as threatened with extinction before being properly described or discovered. This updated checklist provides detailed information about the distribution and habitat of each recorded species. Species richness, distribution patterns, and diversity of ostracod species regionally and in different freshwater ecoregions are also discussed. We found low alpha (site) diversity (mean 3.3 species per site) and a significant difference in species composition and beta diversity of the Okavango ecoregion versus the Kalahari and Zambezian Lowveld ecoregions.
13
Radhakrishnan, K., S. M. Hussain, P. Prakasheswar e S. Gomathi. "Distribution of recent benthic Ostracoda around, Appa Island, Gulf of Mannar, India". Journal of the Palaeontological Society of India 68, n. 2 (dicembre 2023): 293–301. http://dx.doi.org/10.1177/05529360231219625.
Testo completoAbstract (sommario):
The present work reports the distribution of Ostracoda from the surface sediments around Appa Island in the Gulf of Mannar, Tamil Nadu, southeast coast of India. In total, 33 surface sediment and bottom-water samples were collected for this study. In the study area, 34 Ostracoda species belonging to 30 genera, 17 families, 4 superfamilies, 3 suborders, 2 orders and 2 subclasses have been identified. Distribution of species as abundant, common and rare, for every station is being recorded. Among the identified 33 ostracod species, 5 are abundant, 4 are common and the remaining 24 are rare. The total population is higher in the southern part of the island, whereas the northern part of the island has a lower population comparatively. The Ostracoda are indicative of high energy, oxygenated environments in the study area, not conducive for juvenile forms. The ratio of carapaces to open valves of Ostracoda indicates a relatively moderate rate of sedimentation.
14
Park, Lisa E., e R. Douglas Ricketts. "Evolutionary History of the Ostracoda and the Origin of Nonmarine Faunas". Paleontological Society Papers 9 (novembre 2003): 11–36. http://dx.doi.org/10.1017/s1089332600002138.
Testo completoAbstract (sommario):
The Ostracoda are one of the most diverse arthropod groups alive today; they also have a tremendous fossil record. Because of their widespread environmental distributions, small size and carbonate shell, they have become extremely useful biostratigraphic and paleoenvironmental proxy indicators, particularly in nonmarine environments. Despite this utility, little is known about the phylogenetic history of this important group. We reconstructed a phylogenetic history of the major orders and suborders of Ostracoda in order to test the legitimacy of current classification schemes, determine if it is possible for ostracodes to have a Precambrian origin, and test the fidelity of some of the major morphological characters that have documented trends of either increased complexity, such as the hinge and marginal pore canals, or reduction in segments, such as the adductor muscle scar.In our phylogenetic analysis to test taxonomic fidelity, we coded seven morphological hard part characters for nine taxa from the orders Archaeocopida, Leperditicopida, Palaeocopida, Podocopida, and Myodocopida. A parsimony analysis was performed using PAUP (v. 4.0) yielding 4 trees of 17 steps with low levels of homoplasy and a strong phylogenetic signal. A majority rule consensus tree indicates there is not complete agreement between the standard classification scheme and the phylogeny produced by the characters used to establish the classification. In our complete analysis of Ostracoda, we coded 28 morphological characters that included 14 hard part and 14 soft part characters for twelve taxa that include the Archaeocopida, Leperditicopida, Podocopida, and Myodocopida. A parsimony analysis was completed using PAUP (v. 4.0) yielding 1 tree of 125 steps with low levels of homoplasy and a strong phylogenetic signal. An unrooted analysis of this character set has the Cambrian Archaeopodocopida and the Ordovician-Devonian Leperditicopida in an unresolved polytomy with much younger groups such as the Myodocopina, suggesting a much deeper split in the lineage and a possible Precambrian origin for the Ostracoda. Testing the various character state acquisitions over the tree indicates that the hinge does not show an increase in complexity within a phylogenetic context, while the adductor muscle scars do show a significant trend of decrease in complexity across the tree topology. The marginal pore canals, which are functionally tied to osmoregulation as well as carapace secretion, are extremely homoplastic, indicating that this character, which is related to nonmarine invasions and tolerances, was acquired many times throughout the evolutionary history of Ostracoda.By creating an evolutionary framework for the Ostracoda such as is presented here, we can further assess character state acquisition, and how it functionally and evolutionarily relates to ostracode paleoenvironmental tolerances. The framework will not only allow us to understand the overall evolution ofthis group but will also allow us to compare the history of the ostracode clade with other groups that also have a history ofmarine and nonmarine transitions.
15
K, Elumalai, Ramachandran A, Hussain S M e Stephen Pitchaimani V. "Textural characteristics and distribution of ostracoda in core sediments from the Gadilam river estuary, Cuddalore, Tamil Nadu, southeast coast of India". Indian Association of Sedimentologists 40, n. II (30 dicembre 2023): 27–39. http://dx.doi.org/10.51710/jias.v40iii.324.
Testo completoAbstract (sommario):
To know the distribution of brackish water Ostracoda and to investigate the sediment characteristics, a core (105 cm) has been collected from the Gadilam river estuary and it was sub-sampled into 21 samples at 5 cm width regular interval. All the sediment samples were analyzed as per standard micropaleontological techniques in order to investigate the distribution and occurrence of ostracod fauna. A total of 27 ostracod taxa belonging to 16 genera, 12 families, 3 superfamilies and 2 sub-order of the order Podocopida, have been identified based on published articles Throughout the core (from top to bottom) the calcareous forms were noticed. The ostracod species Kalingella mckenziei and Jankeijcythere mckenziei are widely distributed in the core and they outnumbered the rest of the species. The faunal assemblages recorded are tropical, brackish to neritic (shallow marine) and benthic in nature (Hemicytheridea paiki, Hemicytheridea bhatiai, Jankeijcythere mckenziei, Kalingella mckenziei, Neosinocythere dekrooni, Paijenborchellina sp., Stigmatocythere indica and Tanella gracilis). In the analyzed core, there is no faunal assemblage at the depth between 80-85 and 95-105 cm. The sediment characteristics such as calcium carbonate, organic matter and sand-silt-clay ratio also determined and correlated with the observed ostracod populations. Based on the detailed study, it is noticed that high calcium carbonate and low organic matter of the sediment are congenial for population abundance. From the overall distribution of Ostracoda in all the subsamples, siltysand is found to an accommodative substrate for the prosperity of Ostracoda. The statistical aspect of ostracod carapace-valve ratio has been studied to identify the rate of sedimentation which infers a faster rate of deposition of sediments in the Gadilam River estuary.
16
Schön, Isa, e Koen Martens. "Ostracod (Ostracoda, Crustacea) genomics — Promises and challenges". Marine Genomics 29 (ottobre 2016): 19–25. http://dx.doi.org/10.1016/j.margen.2016.03.008.
Testo completo
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Smith, Robin James. "Possible fossil ostracod (Crustacea) eggs from the Cretaceous of Brazil". Journal of Micropalaeontology 18, n. 1 (1 giugno 1999): 81–87. http://dx.doi.org/10.1144/jm.18.1.81.
Testo completoAbstract (sommario):
Abstract. Spherical objects recovered from the acetic acid preparation residues of vertebrate fossils from the Santana Formation (Lower Cretaceous) of northeast Brazil are postulated as the eggs of the ostracod Pattersoncypris micropapillosa Bate, 1972 (Ostracoda). These spheres are phosphatized and range from 85 to 110 μm in diameter, and are comparable in many respects to the eggs of several Recent ostracod species.
18
Kuchankar, Sonal W., Ramdas R. Kamdi, Paresh R. Patel e Dnyaneshwar B. Khamankar. "Seasonal variations in ostracod species in two freshwater lakes in Yavatmal District (Maharashtra) India". Environment Conservation Journal 24, n. 4 (18 ottobre 2023): 259–63. http://dx.doi.org/10.36953/ecj.25792687.
Testo completoAbstract (sommario):
The diversity and density of ostracods (zooplankton) in two freshwater lakes in the Yavatmal district of Maharashtra, India, were studied from June 2020 to May 2021 to determine seasonal variations. Plankton net (64m pore size) was used to collect the samples and analysis was performed using standard keys. In all, 11 species from 8 genera belonging to 3 families of Ostracoda were identified from Mama Lake and Singhada Lake of the Yavatmal district of Maharashtra, India. The overall population of Ostracoda is greater in Mama Lake than in Singhada Lake. Additionally, the species diversity was higher in the summer season and lowest in winter.
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Whatley, Robin C., e Graham P. Coles. "Global Change and the Biostratigraphy of North Atlantic Cainozoic deep water Ostracoda". Journal of Micropalaeontology 9, n. 2 (1 marzo 1991): 119–32. http://dx.doi.org/10.1144/jm.9.2.119.
Testo completoAbstract (sommario):
Abstract. The biostratigraphical distribution of deep-sea (>1000m) Palaeocene to Recent benthonic Ostracoda, based on nannofossil NP and NN zones is presented. By excluding very rare species and those represented by juveniles, 184 species are used in constructing range tables from a total fauna for the interval of 230 species. The vertical distribution of these specimens clearly allows of the recognition of all the major stratigraphical units within the Cainozoic and is also sufficiently precise to distinguish most of the nannofossil zones. The principal criteria employed are the first and last appearances of taxa. While eminently possible to create a series of ostracod zones, it is argued that they are best employed in the recognition of particular levels within the existing nannofossil scheme. The interpretation of the range tables is complicated in places by large numbers of Lazarus taxa and also by the fact that many of the ‘originations’ actually record the arrival of immigrants from the Indo-Pacific.Graphs of both simple and cumulative species diversity, and of origination and extinction rates, are used to demonstrate major faunal events such as the first arrival in the area, during the Middle Eocene, of cosmopolitan deep-sea species, or the very marked, but stepped, Palaeogene-Neogene faunal turnover. The distribution patterns of the Ostracoda record such global changes as the formation of the psychrosphere and the inception of a marked thermocline but they do not, as other authors have suggested, indicate a dramatic faunal turnover at the Eocene-Oligocene boundary. The more vigorous circulation patterns of the Oligocene, related to the opening of the Drake Passage, are reflected in enhanced ostracod diversity at that time. Elevated late Oligocene extinction rates may be correlated with cooling consequent upon the growth of polar ice. Similarly, Lower Miocene low levels of diversity may be associated with the closure of the Iberian Portal and the effective isolation of the Tethys. The deep-sea ostracods do not, for the most part, record such events as the mid-Pliocene warming nor Quaternary climatic fluctuations.
20
Yassini, I., e BG Jones. "Ostracoda in Lake Illawarra: Environmental factors, assemblages and systematics." Marine and Freshwater Research 38, n. 6 (1987): 795. http://dx.doi.org/10.1071/mf9870795.
Testo completoAbstract (sommario):
Major controls of the distribution pattern and abundance of living ostracod populations in Lake Illawarra, a coastal lagoon south of Wollongong, New South Wales, are salinity and the benthic flora. The biocenotic ostracod assemblage from the intertidal zone around Windang Island is a typical, diverse, upper sublittoral, open ocean fauna. The lake entrance channel, which is a transport corridor for marine sediments into the lagoon, has a restricted ostracod biocenose (14 species) but contains an additional 72 species in the diverse thanatocenose resulting from the mixing of estuarine and marine species. Within the lagoon, the benthic flora influences the ostracod distribution pattern with the most diverse assemblage (13 species) occurring in areas covered by seagrasses. Seagrass distribution is, in turn, controlled by water depth, circulation, turbidity and substrate. Estuarine ostracods associated with the seagrass beds can tolerate florally induced fluctuations in pH from 7 to 10 and in dissolved oxygen from 1 mg l-1 to 14 mg l-1. In the deeper parts of the lagoon with a predominantly mud substrate, the ostracod assemblage is dominated by Osticythere reticulata. Most samples retrieved from the most polluted part of the lagoon contained no ostracods. A total of 90 ostracod species and subspecies belonging to 50 genera has been identified; nine species: Cytheralison cosmetics, Callistocythere janiceburrowsae, Callistocythere windangensis, Neocytherideis anneclarkeae, Actinocythereis robustus, Bradleya rectangulata, Procythereis jonesi, Hemicytherura windangensis and Cytheropteron wrighti; and one subspecies, Callistocythere dorsotuberculata paucicostata, are described as new to science.
21
Wan, Junyu, William J. Foster, Li Tian, Thomas L. Stubbs, Michael J. Benton, Xincheng Qiu e Aihua Yuan. "Decoupling of morphological disparity and taxonomic diversity during the end-Permian mass extinction". Paleobiology 47, n. 3 (1 febbraio 2021): 402–17. http://dx.doi.org/10.1017/pab.2020.57.
Testo completoAbstract (sommario):
AbstractAn increasing number of unexpectedly diverse benthic communities are being reported from microbially precipitated carbonate facies in shallow-marine platform settings after the end-Permian mass extinction. Ostracoda, which was one of the most diverse and abundant metazoan groups during this interval, recorded its greatest diversity and abundance associated with these facies. Previous studies, however, focused mainly on taxonomic diversity and, therefore, left room for discussion of paleoecological significance. Here, we apply a morphometric method (semilandmarks) to investigate morphological variance through time to better understand the ecological consequences of the end-Permian mass extinction and to examine the hypothesis that microbial mats played a key role in ostracod survival. Our results show that taxonomic diversity and morphological disparity were decoupled during the end-Permian extinction and that morphological disparity declined rapidly at the onset of the end-Permian extinction, even though the high diversity of ostracods initially survived in some places. The decoupled changes in taxonomic diversity and morphological disparity suggest that the latter is a more robust proxy for understanding the ecological impact of the extinction event, and the low morphological disparity of ostracod faunas is a consequence of sustained environmental stress or a delayed post-Permian radiation. Furthermore, the similar morphological disparity of ostracods between microbialite and non-microbialite facies indicates that microbial mats most likely represent a taphonomic window rather than a biological refuge during the end-Permian extinction interval.
22
Martens, Koen, Isa Schön, Claude Meisch e David J. Horne. "Global diversity of ostracods (Ostracoda, Crustacea) in freshwater". Hydrobiologia 595, n. 1 (18 dicembre 2007): 185–93. http://dx.doi.org/10.1007/s10750-007-9245-4.
Testo completo
23
Lawrence, James R., Kiseong Hyeong, Rosalie F. Maddocks e Kwang-Sik Lee. "Passage of Tropical Storm Allison (2001) over southeast Texas recorded in δ18O values of Ostracoda". Quaternary Research 70, n. 2 (settembre 2008): 339–42. http://dx.doi.org/10.1016/j.yqres.2008.04.004.
Testo completoAbstract (sommario):
AbstractFreshwater Ostracoda collected in ephemeral pond-waters derived from Tropical Storm Allison (2001, Texas) recorded the unusually low oxygen-isotope values of that storm. Therefore, the potential clearly exists, in locations where tropical cyclones make landfall, to obtain a long-term record of tropical cyclone activity from fossil ostracode calcite.
24
Arias, Carmen. "Diversity dynamics of Early Jurassic ostracods of the Cordillera Ibérica (Spain) and the re-evaluation of the Pliensbachian–Toarcian mass extinction". Canadian Journal of Earth Sciences 44, n. 10 (1 ottobre 2007): 1397–411. http://dx.doi.org/10.1139/e07-018.
Testo completoAbstract (sommario):
The extinction and recovery of Ostracoda at the Pliensbachian–Toarcian (P–T) boundary are analyzed based on a database of taxonomically revised Pliensbachian to Toarcian transition ostracod assemblages. In contrast to earlier assertions, the results of this study indicate that ostracod extinction rates were significant in comparison with other marine invertebrates. An extinction rate of 54% has been calculated for upper Pliensbachian ostracod species occurring in more than one section. Diversification took place in the latest Pliensbachian (Spinatum Zone) and early Toarcian (Tenuicostatum Zone), whereas diversity decrease occurred in the middle early Toarcian (Strangewaysi Subzone, Serpentinus Zone). This notable diversity decline in the early Toarcian corresponds to a global mass extinction time, whose peak has been documented in the Tenuicostatum Zone. Meanwhile, the ostracod mass extinction occurred within the Serpentinus Zone and was followed by radiation and recovery in the succeeding Bifrons Zone. Similar diversity changes of ostracods are observed in other European areas, although in the Cordillera Ibérica, the demise began later. Many aspects of this event are still debated, and there is no common cause or single set of climatic or environmental changes common to this event. The supposed extinction-causing environmental changes resulting from anoxia episodes are unclear and are unlikely to have been of sufficient intensity or geographic extent to cause this global extinction. In this paper, the decrease in marine species diversity is explained by a new palaeoceanographic scenario, in which a rapid global cooling episode is regarded as the ultimate cause.
25
Nahnah, Raouia, e Sana Benmansour. "Mixed marine, brackish water, non-marine, and subaerial microfaunal association in the Red Marls Formation of the Western Aurès Basin (Upper Paleocene)". Revista Brasileira de Paleontologia 26, n. 3 (23 ottobre 2023): 197–211. http://dx.doi.org/10.4072/rbp.2023.3.05.
Testo completoAbstract (sommario):
In the western part of the Aurès Basin (northeastern Algeria), the Red Marls of El Kantara Formation records a mixed microfaunal association of non-marine-brackish ostracoda, marine foraminifera, lacustrine charophytes, and subaerial Microcodiums. Based on the recovered biotic component, it is considered that the Red Marls of El-Kantara Formation date from the upper Paleocene (Thanetian). Seven species of brackish water (Neocyprideis raoi) and non-marine ostracoda (Frambocythere tumiensis anjarensis, Paracypretta jonesi, Paracypretta verruculosa, Limnocythere deccanensis, Darwinula torpedo and Zonocypris spirula), have been discovered for the first time in Algeria and on the south Tethyan margin. Paleoenvironmentally, the overall biotic assemblage recovered indicates the presence of a freshwater palustrine/lacustrine depositional system connected to a low energy stream/river. This indicates that marginal marine conditions were prevalent in northeastern Algeria’s far inland regions. Paleobiogeographically, the seven known ostracod species have limited distributions that are until now common only with India. However, this disproved the theory that these species are endemic to the Indian Subcontinent, which is confirmed by their association with cosmopolitan charophytes. Keywords: limnic ostracoda, charophytes, paleobiogeography, Thanetian, western Aurès, Algeria.
26
Salvi, Gianguido, John B. Anderson, Marco Bertoli, Pasquale Castagno, Pierpaolo Falco, Michele Fernetti, Paolo Montagna e Marco Taviani. "Recent Ostracod Fauna of the Western Ross Sea (Antarctica): A Poorly Known Ingredient of Polar Carbonate Factories". Minerals 12, n. 8 (25 luglio 2022): 937. http://dx.doi.org/10.3390/min12080937.
Testo completoAbstract (sommario):
Ostracoda are a minor but recurrent component of Southern Ocean marine carbonate factories, and their low-Mg calcitic skeletal mineralogy helps in ensuring a noteworthy post-mortem resilience. Our study, based upon surface sediment occurrences, contributes to the better definition of their distribution vs. potential controlling factors in Antarctic waters. The ostracod fauna from the Western Ross Sea Shelf appears dominated by Australicythere polylyca, Australicythere devexa, Xestoleberis rigusa, Loxoreticulatum fallax, Cativella bensoni, Austrotrachyleberis antarctica and Patagonacythere longiducta, colonizing a variety of shelf environments along a wide bathymetric range. The abundance and richness values correlate well to nutrient distribution and sediment supply, primarily related to the circulation of different oceanographic regimes affecting the floor of the Ross Sea Shelf. Circumpolar Deep Water could represent the main factor controlling the distribution of ostracods. Similar results (high abundance and richness in ostracod values) were also recorded in the Terra Nova Bay and in a nearby area characterized by warm water rich in nutrients and composed of water of circumpolar origin flowing from the open ocean southwards onto the continental shelf. Particulate Fe (pFe), in suspended particulate matter (SPM), and other particulate trace metals in TNB could support the hypothesis that biogenic iron may significantly contribute to the bioavailable iron pool, sustaining both primary production and ostracod fauna richness in this area.
27
Van den Broecke, Lynn, Jacques Vanfleteren, Koen Martens e Isa Schön. "Hurdles in investigating UVB damage in the putative ancient asexual Darwinula stevensoni (Ostracoda, Crustacea)". Belgian Journal of Zoology 143, n. 2 (13 marzo 2024): 106–18. http://dx.doi.org/10.26496/bjz.2013.131.
Testo completoAbstract (sommario):
Ostracoda or mussel-shrimps are small, bivalved Crustacea. Because of their excellent fossil record and their broad variety of reproductive modes, ostracods are of great interest as a model group in ecological and evolutionary research. Here, we investigated damage and repair from one of the most important biological mutagens, namely UVB radiation, in the putative ancient asexual ostracod Darwinula stevensoni from Belgium. We applied three different methods: the Polymerase Inhibition (PI) assay, Enzyme-Linked Immuno Sorbent Assay (ELISA) and dot blot. All three techniques were unsuccessful in quantifying UVB damage in D. stevensoni. Previous experiments have revealed that the valves of D. stevensoni provide an average UVB protection of approximate 60%. Thus, UVB damage could be too little to make quantitative experiments work. Additionally, variation between individual ostracods due to season and age most likely contributed further to the failure of the three used experimental approaches to quantify damage. In a second experiment, we investigated the influence of temperature on survival of D. stevensoni during UVB exposure. The estimated relative lethal UVB dose at 4°C was with 50 kJ/m2, significantly lower than at room temperature, with 130 kJ/m2. This could either indicate lack of adaptation to low temperatures and/or the presence of metabolic processes active at room temperature protecting against UVB damage in D. stevensoni. The latter possibility could also explain why the estimated relative lethal UVB dose of D. stevensoni is similar to that of other non-marine ostracods where valves provide around 80% protection, despite the valves of D. stevensoni providing less protection. If such metabolic processes can repair UVB damage quickly, this may provide an alternative explanation why we could not quantify UVB damage in D. stevensoni.
28
Boomer, Ian, Nigel R. Ainsworth e John Exton. "A re-examination of the Pliensbachian and Toarcian Ostracoda of Zambujal, west-central Portugal". Journal of Micropalaeontology 17, n. 1 (1 aprile 1998): 1–14. http://dx.doi.org/10.1144/jm.17.1.1.
Testo completoAbstract (sommario):
Abstract. Pliensbachian and Toarcian Ostracoda first described by Exton (Geological Paper, Carleton University, Ottawa, 79: 1–104 1979) from the Lusitanian Basin, west-central Portugal have been re-examined. As a result, a greater diversity in the Ostracoda (80 species) is now recognized. Two species are newly described (Eucytherura zambujalensis sp. nov., Ektyphocythere mediodepressa sp. nov.) from the marls and calcareous shales of the Maria Pares Hill section near the village of Zambujal. Poor preservation precludes a complete taxonomic review of the present material. Five ostracod zones are proposed; Gammacythere ubiquita–Ogmoconchella gruendeli Zone, Poly cope cerasia–Polycope cincinnata Zone, Liasina lanceolata–Ogmoconcha convexa Zone, Bairdiacypris rectangularis–Kinkelinella sermoisensis Zone, and Cytherella toarcensis-Kinkelinella costata Zone. Although the ostracod assemblages possess strong similarities to those described from Northwest Europe, some of the Zambujal assemblages are dominated by the genus Polycope. A marked faunal turnover, in association with the extinction of the Metacopina occurs in the lower Subzone of the tenuicostatum Zone of Lower Toarcian age. These faunal events are discussed in relation to changing environmental conditions.
29
Kramer, Michael, e Jonathan Holmes. "Taxonomy and palaeoecology of Ostracoda from the Middle to Late Pleistocene upper Karewa formation of Kashmir Valley, Northern India". Journal of Micropalaeontology 28, n. 1 (1 maggio 2009): 25–36. http://dx.doi.org/10.1144/jm.28.1.25.
Testo completoAbstract (sommario):
Abstract. Ostracoda from a 25 m thick exposure in sediments of the upper Karewa formation indicate lacustrine conditions in the Kashmir intermontane basin during the Middle to Late Pleistocene. The Middle to Late Pleistocene age is established on the basis of lithostratigraphy and confirmed by two thermoluminescence age determinations at the top of the section. The ostracod assemblages show that the lake water remained fresh or, at most, was very slightly saline, throughout the period represented by the section. Nearly all ostracod taxa identified from the sediments are cold stenothermal forms and they include inhabitants of the littoral and profundal domain as well as running waters and springs. The Ostracoda present within the section indicate that during deposition of the upper Karewa sediments a large, but fairly shallow, well-oxygenated open-basin freshwater lake existed in that central part of the Kashmir Basin. Although the sequences suggest changes in water depth may have occurred, lacustrine conditions were otherwise largely unchanged over the period represented by the section, up until the demise of the lake during the early part of the Late Pleistocene.
30
Dewi, Kresna Tri, Noor C. D. Aryanto e Yogi Noviadi. "LAND-SEA INTERACTIONS IN COASTAL WATERS OFF NE KALIMANTAN: EVIDENCE FROM MICROFAUNAL COMMUNITIES". BULLETIN OF THE MARINE GEOLOGY 22, n. 1 (15 febbraio 2016): 1. http://dx.doi.org/10.32693/bomg.22.1.2007.1.
Testo completoAbstract (sommario):
Microfauna (ostracoda and foraminifera) as component of sediments has been used to detect the dynamics of sea floor condition in NE Kalimantan, particularly off Nunukan and Sebatik Islands. In general, the microfaunal components tend to increase (both number of species and specimens) from near shore to the open sea. The microfauna occur rarely at locations surrounding the islands due to high content of plant remains from the land. The marine origin of microfaunas occurs very abundantly in the inner part of the study area between Tinabasan and Nunukan Islands. This finding is interested due to their occurrence as unusual forms: brownish shells, broken and articulated ostracod carapaces. Additional interested findings are: the incidence of abraded test of Elphidium, the occurrence of dominant species of both ostracoda and foraminifera at some stations; various morphological forms of foraminiferal genus, Asterorotalia that reaches about 1% and distributed in the open sea. The various unusual forms may relate to the dynamics of local environmental changes such as postdepositional accumulation in the sediment, biological activities, and drift currents from open sea to landward.
Keywords: Ostracoda, Foraminifera, North East Kalimantan, land-sea interaction
Mikrofauna (ostracoda dan foraminifera), sebagai komponen sedimen dapat digunakan untuk mendeteksi dinamika kondisi dasar laut di Kalimantan Timur, tepatnya di sekitar Pulau Nunukan dan Sebatik. Secara umum, komponen mikrofauna cenderung bertambah (baik dalam jumlah spesies maupun spesimen) dari perairan sekitar pantai ke arah laut lepas. Mikrofauna yang ditemukan sangat jarang di lokasi sekitar pulau-pulau disebabkan oleh keterdapatan sisa-sisa tanaman dari daratan. Mikrofauna asal lautan ditemukan sangat melimpah di bagian dalam daerah penelitian antara Pulau Tinabasan dan Nunukan. Temuan ini sangat menarik karena adanya bentukan abnormal: cangkang berwarna kecoklatan, rusak dan cangkang ostracoda berbentuk tangkupan. Temuan tambahan yang juga menarik adalah: keterdapatan cangkang Elphidum yang rusak, keterdapatan beberapa spesies ostracoda dan foraminifera secara dominan di titik lokasi tertentu, dan kenampakan morfologi yang bervariasi dari genus foraminifera, Asterorotalia, yang mencapai 1% dan tersebar di laut lepas. Berbagai bentukan abnormal tersebut kemungkinan berkaitan dengan dinamika kondisi lingkungan setempat seperti akumulasi setelah pengendapan dalam sedimen, aktivitas biologis dan alur arus dari laut terbuka kearah daratan.
Kata kunci: ostracoda, foraminifera, Kalimantan Timur, interaksi daratan-lautan
31
Al-Ibady, Qater Al-Nada Ali Kanaem. "Effect of Magnetotron on the Rates of Growth and Fecundity in Ostracoda Cyprislaevis O.F Müller,1776 under the Laboratory Conditions". Journal of Biotechnology Research Center 8, n. 4 (1 dicembre 2014): 42–45. http://dx.doi.org/10.24126/jobrc.2014.8.4.381.
Testo completoAbstract (sommario):
The Magneototron technique considers as recent and advanced techniques in magnetic water treatment, which application in different; ecological, agricultures, industrial, medical and scientific fields. Therefore this study making to determine the effects of Magnetotron system with different intensities 0.05,0.10 and 0.15 Tesla on some biological aspects for one species of freshwater Ostracoda cyprislaevis O.F. Müller, 1776 for economical important, because both juveniles and adults of fishes feeding on it and as a tool for water cleaning, which consideration feeding on dead and decay animals and vegetables The samples of Ostracoda were collected from Al-Jaesh canal- Baghdad province for period from 1/9/2012 to 1/11/2012.The obtained results compared with this species of Ostracoda which lived in raw water (unexposed to magnetotron system).The present study demonstrated increased significance the rates of growth by increased the bivalve carapace dimensions (length and width) for both ostracodean males and females with increased intensity of magnetotron system comparative with untreated water. Although increase significant observed in fecundity in ostracodean females by increase the number and diameter of eggs with increased intensity comported with untreated females. Also this study detected to predominant females upon males in both treated and untreated water with magnetotron system. Then the magnetotron system does not effect on heterogonous in sexual formation for this species in same ecosystem.
32
Holmes, Jonathan A. "Recent non-marine Ostracoda from Jamaica, West Indies". Journal of Micropalaeontology 16, n. 2 (1 ottobre 1997): 137–43. http://dx.doi.org/10.1144/jm.16.2.137.
Testo completoAbstract (sommario):
Abstract. Ostracods were sampled qualitatively at 22 sites from 15 waterbodies in the western part of Jamaica and determinations of the water chemistry and habitat characteristics were made at each locality. Most of the ostracods found belong to the Cypridinae, Cypridopsinae, Cyclocypridinae and Darwinulidae. There is a clear distinction between the faunas found in the larger, permanent lakes and the smaller ponds. The latter are subject to large fluctuations in volume and may desiccate either seasonally or interannually. Within the largest lake, Wallywash Great Pond, there is some degree of spatial zonation in the ostracod faunas that appears to be related to water depth and aquatic macrophyte occurrence. The distribution of modern ostracods within Wallywash Great Pond suggests that the late Quaternary faunal sequence from this lake is primarily a function of lake-level changes.
33
SABATER, LARA MILENA, MATEO DANIEL MONFERRAN, JANET HIGUTI e ALEJANDRA PATRICIA PÉREZ. "An annotated checklist of recent non-marine Ostracoda (Crustacea) from Argentina, South America". Zootaxa 5336, n. 2 (22 agosto 2023): 151–78. http://dx.doi.org/10.11646/zootaxa.5336.2.1.
Testo completoAbstract (sommario):
According to an updated list of extant non-marine ostracods, there are 2,330 subjective species in 270 genera in the world, of which 333 species are known from the Neotropical region. However, the knowledge about the ostracod fauna in Argentina is scarce, fragmented and incomplete. Thus, the aim of this study was to present the first checklist of the recent non-marine ostracods from Argentina, including geographical distributions and ecological characteristics of the species. Thus far, 66 ostracod species in 33 genera and 7 families have been recorded in non-marine Argentinian environments. Of the total number of species, 29% can be considered endemic to the country. Most of the species were recorded in alkaline, freshwater to oligohaline cold waters and mainly in low to moderate altitude environments. Our results showed that most studies were mainly carried out in the Pampean and Patagonia region and, therefore, the diversity record of ostracods in Argentina is biased towards these regions.
34
Mestre, Alexandre, Juan S. Monrós e Francesc Mesquita-Joanes. "A review of the Entocytheridae (Ostracoda) of the world: updated bibliographic and species checklists and global georeferenced database, with insights into host specificity and latitudinal patterns of species richness". Crustaceana 87, n. 8-9 (2014): 923–51. http://dx.doi.org/10.1163/15685403-00003337.
Testo completoAbstract (sommario):
The creation of biodiversity datasets freely available for the scientific community is a valuable task to stimulate global research on biodiversity. Among others, the Global Biodiversity Information Facility (GBIF) is a remarkable resource providing free online access to biodiversity data on many diverse taxonomic groups (including Ostracoda) from both terrestrial and marine ecosystems. More specific databases for Ostracoda georeferenced data have been built (e.g., NACODe and OMEGA), some with freely available data. However, the Entocytheridae, a family of ostracods living commensal on other crustaceans, with 220 living species, representing the third non-marine ostracod family in number of species, has been remarkably under-represented in the currently available biodiversity databases. To cover this gap, we present here a free-access world database of Entocytheridae published in GBIF and review the current knowledge of the group by updating a bibliographic and species checklists of the Entocytheridae. We also analyse the host specificity of the group and the latitudinal species richness pattern in North and Central America (including 186 spp.). The current database includes 3509 georeferenced records from 220 species, in contrast to just 44 entocytherid georeferenced records previously published in GBIF. In addition, the updated species list accounts for 43 species and 2 genera that were not included in the previous compendium on Entocytheridae published by Hart & Hart in 1974, so as 40 species not included in the 2013 Checklist provided by the Catalogue of Life. We show that the specialisation in one unique host species is not the rule in Entocytheridae, and evidence an unusual latitudinal pattern of species richness in North and Central American entocytherids, most probably related to the biogeographic history of their hosts.
35
Zhai, Dayou, Robin J. Smith, Ping Peng, Na Yu, Shunxin Ma e Xiangzhong Li. "Cluster analyses of Ostracoda based on dimensions of body structures: implications for taxonomic classification". Crustaceana 90, n. 4 (2017): 471–502. http://dx.doi.org/10.1163/15685403-00003667.
Testo completoAbstract (sommario):
We measured selected podomeres, setae and claws in different ostracods and calculated the between-specimen morphological difference, which is expressed as a Canberra dissimilarity index. Our data indicate that morphological differences between ostracods increase with their taxonomic distance. Cluster analyses of ostracod specimens based on Canberra dissimilarity are able to discriminate different species and concur with existing classifications. We suggest that the dimensions of body structures are taxonomically valuable, and that ostracod species identification can be assisted based on the dimensional data of body structures. Species discrimination with such a method does not rely on explicit morphological hiatuses, such as the presence/absence of particular setae, but instead utilizes measurable morphological differences. Our numerical methods also show good potential for studying phenotypic diversity. Analyses on ostracod populations from isolated temporary pools and those from permanent but geographically distant habitats indicate that dispersal improbability is responsible for the observed morphological differentiation.
36
Scharf, Burkhard, e Finn A. Viehberg. "Living Ostracoda (Crustacea) from the town moat of Bremen, Germany". Crustaceana 87, n. 8-9 (2014): 1124–35. http://dx.doi.org/10.1163/15685403-00003345.
Testo completoAbstract (sommario):
Between 2009 and 2014 we collected 23 ostracod species in the historical town moat of Bremen, Germany. Today, the moat is part of an urban park, separated into six basins by various bridges. Brackish water, pumped from the Weser River into the moat, regulates the water level and is the main factor controlling the various physical and chemical parameters of the basins. Brackish water ostracod species originate from this artificial inflow, but only a minority of these species establishes stable populations. The Bremen moat ostracod assemblages are compared with the moat of Greifswald. The different environmental setting (e.g., water current) and the number of studied localities can explain the differences in the occurrence of ostracods in these two localities.
37
Shareef, Najed, Maher Mahdi e Abbas Mohamed. "Combined Ostracoda and Foraminiferal Biozonation with Environment of Fatha Formation (Middle Miocene) In Different Oilfields, Southern Iraq". Iraqi Geological Journal 56, n. 1D (30 aprile 2023): 188–211. http://dx.doi.org/10.46717/igj.56.1d.15ms-2023-4-24.
Testo completoAbstract (sommario):
The Fatha Formation is a significant stratigraphic unit that was deposited during the Miocene; its sediments covered the basin from the north to the south of Iraq. Six oil wells within four oilfields were chosen for the current study. Both types of samples (core and cutting) were prepared to extract the existing fossils. Forty-two foraminifera species belonging to twenty-one genera and forty ostracods species belonging to thirty genera were identified. On the basis of the biostratigraphic distribution of the foraminifera and ostracoda species, one biozone for foraminifera was plotted which is Elphidium craticulatum taxon range zone, also one biozone of ostracoda was determined which is Schneiderella unispinata Assemblage zone. The age of Fatha Formation is Middle Miocene depending on the index fossils of the ostracods. All genera recorded in the study area belong to benthic foraminifera except one genus (Globigerina quinquelob) belongs to the planktonic foraminifera. The environment of the Fatha Formation in the southern basin is slightly different from the northern basin, but the main environment is still a lagoon but it is accompanied by several other environments such as shallow water, tidal and subtidal. The lagoon was partially closed, and it was affected by marine water, especially in the lower part of the studied formation.
38
Barbieri, Giulia, e Stefano Claudio Vaiani. "Benthic foraminifera or Ostracoda? Comparing the accuracy of palaeoenvironmental indicators from a Pleistocene lagoon of the Romagna coastal plain (Italy)". Journal of Micropalaeontology 37, n. 1 (29 gennaio 2018): 203–30. http://dx.doi.org/10.5194/jm-37-203-2018.
Testo completoAbstract (sommario):
Abstract. Integrated analyses of multiple groups of microfossils are frequently performed to unravel the palaeoenvironmental evolution of subsurface coastal successions, where the complex interaction among several palaeoecological factors can be detected with benthic assemblages. This work investigates the palaeoenvironmental resolution potential provided by benthic foraminifera and ostracoda within a Pleistocene lagoonal succession of the Romagna coastal plain (northern Italy). Quantitative approaches and statistical techniques have been applied to both groups in order to understand the main factors that controlled the composition of assemblages and compare the palaeoecological record provided by single fossil groups. The two faunal groups are characterized by the high dominance of opportunistic species (Ammonia tepida–Ammonia parkinsoniana and Cyprideis torosa); however, detailed palaeoecological information is inferred from less common taxa. Benthic foraminiferal assemblages are mainly determined by the frequencies of abnormal individuals and species related to high concentrations of organic matter, showing two assemblages: a stressed assemblage, consistent with a brackish-water environment subject to salinity and oxygen fluctuations, and an unstressed assemblage, which indicates more stable conditions. Despite the lower number of species, ostracoda show more significant differences in terms of species composition and ecological structure between their three assemblages, formed in response to a salinity gradient and indicative of inner, central, and outer lagoon conditions. The stratigraphic distribution of ostracod assemblages shows a general transgressive–regressive trend with minor fluctuations, whereas benthic foraminifera highlight the presence of a significant palaeoenvironmental stress. In this case, the higher abundance along the stratigraphic succession, the higher differentiation of the assemblages, and the well-defined relationship between taxa and ecological parameters determine Ostracoda as the most reliable fossil group for precise palaeoenvironmental reconstructions. Nevertheless, benthic foraminifera indicate palaeoenvironmental stress and can be used to refine the environmental interpretation in the presence of monospecific ostracod assemblages.
39
Friedman, Gerald M., e Robert F. Lundin. "Freshwater ostracodes from upper Middle Devonian fluvial facies, Catskill Mountains, New York". Journal of Paleontology 72, n. 3 (maggio 1998): 485–90. http://dx.doi.org/10.1017/s0022336000024240.
Testo completoAbstract (sommario):
Leperditiocope ostracodes identified asSollenella? sp. were discovered in the Gilboa Formation (upper Givetian, uppermost Middle Devonian) within the continental Catskill Magnafacies of New York State. The deposits in which the ostracodes were found are meandering-fluvial facies that were part of a vast alluvial plain that sloped westward from the eroding Acadian Mountains. Hence, ostracodes colonized freshwater habitats earlier than heretofore thought. It has been widely accepted that, until now, the oldest known unequivocal occurrences of freshwater ostracodes are of Late Carboniferous age. This new discovery means that the first colonization of freshwater habitats by Ostracoda occurred approximately 60 million years earlier than previously known.
40
Eagar, Stephen H. "Freshwater Ostracoda from Tarawa, Kiribati: their implications for dispersal mechanisms". Journal of Micropalaeontology 19, n. 1 (1 maggio 2000): 68. http://dx.doi.org/10.1144/jm.19.1.68.
Testo completoAbstract (sommario):
Abstract. Tarawa Atoll, Gilbert Islands (1° 30′N, 173° 00′E) is an isolated place, comparatively recently emergent – 2500 years bp and 2 – 3 m above present sea-level (Marshall & Jacobson, 1985). During the course of a study of the marine ostracods (Eagar, in press) it was noted that there are relatively few places where freshwater is visible on the surface of the atoll. This is not unusual, given the low precipitation (154 mm a−1) and the daytime temperatures of Tarawa (27–30°C). Five freshwater ponds on South Tarawa (Fig. 1) were examined and two species of Ostracoda were found: Cyprinotus cingalensis Brady, 1886 and Limnocythere notodonta Vávra, 1906. At Bairiki (locality A), a pond adjacent to the causeway linking Bairiki with Betio was sampled and yielded abundant Cyprinotus cingalensis. Other ponds were found at Ambo (Locality B) and Temaiku Bight (Localities C and D with two ponds). Only the pond (Locality B), an established babai pit (taro; Cyrtosperma chamissonis), adjacent to the roadside at Ambo yielded further specimens of the ostracod Limnocythere notodonta, although in low numbers.The question of how these species were introduced onto Tarawa Atoll is intriguing. C. cingalensis is known from Ceylon (Brady, 1886), Hawaii and the Sandwich Islands. The record by Vávra (1906) from Australia may be incorrect. Limnocythere notodonta was previously recorded only from Java (Vávra, 1906). Both species may have been distributed in the same way that Sars (e.g., Sars, 1896) transported species from different parts of the world to Norway to describe . . .
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Fylypchuk, Tatiana, e Iryna Sytnikova. "The estimation of pesticides toxicity with the help of zootest method". Biolohichni systemy 11, n. 1 (20 giugno 2019): 71–80. http://dx.doi.org/10.31861/biosystems2019.01.071.
Testo completoAbstract (sommario):
The following article is the result of biotesting of ecotoxicological danger of pesticides, which are used in gardening. Ten pesticide preparations were selected for the research, six of them are fungicides: flint-star, chorus, score, stroby, topsin-M and median-extra and four of them are insecticides: bi-58, calypso, mospilan and actara. Toxicity of pesticides was identified through analyzing ten times dilution (1:10) of the recommended solution specified by the manufacturer. Not less than three days old tap water served as control. Daphnia, Ostracoda and Danio were selected as test objects. After 1, 2, 3, 4, 5, 24 and 72 hours of exposure the number of dead animals was visually determined and the percentage of survival of testers was calculated. The toxicity of the pesticide preparations was considered as proven if the percentage of test organisms mortality rate was ≥50%. The scale of pesticide toxicity degree was developed, including the percentage of test organisms mortality during certain exposure time (up to 24 or 48 hours). It can be used to define its acute and toxic effect. According to the biotesting results, flint-star and score are the most toxic among the examined pesticide preparations fungicides for aquatic ecosystems, as they showed ultrahigh and high levels of toxicity for zootests. Carp fishes of the genus Danio showed greater sensitivity to the influence of fungicides and lower to insecticides, while for aquatic crustaceous Daphnia and Ostracoda these features were not detected. The sensitivity of the tested test objects to insecticides decreased in an order: Ostracoda sp.→Daphnia sp.→Danio sp. Comparing the sensitivity of aquatic crustaceous in the process of the pesticides biotesting, it was found out that Ostracoda sp. is more sensitive test object than Daphnia sp. Under the same conditions of biotesting, an absolute immobilization of ostracods is two times higher than the immobilization of Branchiopoda.
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BERGUE, CRISTIANINI T., MARIA DA SAUDADE A. S. MARANHÃO e GERSON FAUTH. "Paleolimnological inferences based on Oligocene ostracods (Crustacea: Ostracoda) from Tremembé Formation, Southeast Brazil". Anais da Academia Brasileira de Ciências 87, n. 3 (28 luglio 2015): 1531–44. http://dx.doi.org/10.1590/0001-3765201520140366.
Testo completoAbstract (sommario):
Non-marine Oligocene ostracods from Tremembé Formation (Taubaté Basin, Southeast Brazil) are studied for the first time. The study reveals rich assemblages which are probably composed of many new taxa, two of which are described here. The sixteen ostracod species registered are classified in the generaCypretta Vávra, Strandesia Stuhlmann,Potamocypris Brady, Heterocypris Claus,Eucypris Vávra, Herpetocypris Brady and Norman, Cytheridella Daday and LimnocythereBrady. Two new species of the latter are herein proposed: L. mandubi sp. nov. and L. katu sp. nov. The succession of ostracod assemblages along the studied core changes conspicuously in composition, abundance and preservation, and are characterized by the following associations: Herpetocypris-Cytheridella (lower),Limnocythere-Cypretta (middle) andPotamocypris-Heterocypris (upper). It is assumed that these associations represent different ecological phases of the paleolake Taubaté which is in accordance to previous stratigraphic and paleontological studies in the basin. The results from this pioneering taxonomic and paleoecological study on ostracods from Tremembé Formation reinforce the potential of these fossils for paleolimnological researches in Brazilian Cenozoic deposits.
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Külköylüoğlu, Okan, Alper Ataman, Randy Gibson e Peter Diaz. "A new genus, Tuberocandona gen. nov. (Crustacea, Ostracoda, Candonidae) and past to present ostracod species diversity in Texas (USA)". Subterranean Biology 45 (21 marzo 2023): 119–40. http://dx.doi.org/10.3897/subtbiol.45.98075.
Testo completoAbstract (sommario):
A new ostracod genus, Tuberocandonagen. nov., was collected from Honeycut Hollow Springs, Texas, USA Morphological comparisons and cladistic analyses showed that the new genus displays several different features (e.g. presence of two tubercules on each of the valves, numbers of A1 segments, shape of A2 claws, shape and presence of two claw-like setae on the clasping organs, absence of d2 and dp setae on T2 and T3, absence of alpha and beta setae on Md, shape of hemipenis) from other genera of the tribe. Including the new species, the number of non-marine ostracods known from inland waters of Texas is now 118 species in 45 genera. With the aim of documenting ostracod biodiversity in Texas (USA) by including fossils, we sought documents published from 1927 to 2022 and were able to list 673 ostracod taxa belonging to 142 genera. Among the fossils, 73 ostracods were the oldest records during the Pennsylvanian period (ca. 310 mya), while there were only 42 taxa reported from the Holocene. The Eocene had the highest number of ostracods (126 taxa). In comparison, the living species had only 18 of 673 taxa that were considered nonmarine forms. There are only six species in common with the fossils and recent records. These results suggest the potential for relatively high ostracod species richness and diversity in Texas. This is indeed strongly supported by the present study and the described new genus and its type species (Tuberocandona leonidasisp. nov.).
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LUZ, NATHÁLIA CARVALHO DA, e JOÃO CARLOS COIMBRA. "Ostracods (Crustacea: Ostracoda) of the Vitoria-Trindade Chain, Southwestern Atlantic". Zootaxa 5188, n. 4 (20 settembre 2022): 301–29. http://dx.doi.org/10.11646/zootaxa.5188.4.1.
Testo completoAbstract (sommario):
The current work is part of a taxonomic study on ostracods from Trindade Island and four seamount summits of the Vitoria-Trindade Chain. Twenty-six species belonging to nine families and 17 genera were identified. Five species are described as new, as follows: two Cytheruridae (Hemicytherura trindadensis sp. nov., Semicytherura parva sp. nov.) and three Loxoconchidae (Loxocorniculum micropapillosum sp. nov., Phlyctocythere christophei sp. nov., Phlyctocythere apua sp. nov.). The other taxa are being studied in an ongoing survey.
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Patil, S. G. v., e S. S. Talmale. "A checklist of freshwater ostracods (Ostracoda: Crustacea) of Maharashtra, India". Zoos' Print Journal 20, n. 5 (21 aprile 2005): 1872–73. http://dx.doi.org/10.11609/jott.zpj.1007.1872-3.
Testo completo
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YAMADA, SHINNOSUKE, AKIRA TSUKAGOSHI e NORIYUKI IKEYA. "Carapace formation of the podocopid ostracode Semicytherura species (Crustacea: Ostracoda)". Lethaia 38, n. 4 (dicembre 2005): 323–32. http://dx.doi.org/10.1080/00241160500355160.
Testo completo
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Van der Meeren, T., J. E. Almendinger, E. Ito e K. Martens. "The ecology of ostracodes (Ostracoda, Crustacea) in western Mongolia". Hydrobiologia 641, n. 1 (21 gennaio 2010): 253–73. http://dx.doi.org/10.1007/s10750-010-0089-y.
Testo completo
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Mori, Nataša, e Claude Meisch. "Contribution to the knowledge on the distribution of recent free-living freshwater ostracods (Podocopida, Ostracoda, Crustacea) in Slovenia". Natura Sloveniae 14, n. 2 (4 dicembre 2023): 5–22. http://dx.doi.org/10.14720/ns.14.2.5-22.
Testo completoAbstract (sommario):
An updated checklist of Recent free-living freshwater ostracods (Podocopida, Ostracoda, Crustacea) from Slovenia together with new records is presented. The new checklist is based on both the records extracted from the literature and the sampling in the field carried out during the last decade. The present checklist comprises 61 species. However, the eastern part of Slovenia and the surface waters are underrepresented. It is expected that the number of species will increase in the future.
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Pereira, Letícia C., Fábio A. Lansac-Tôha, Koen Martens e Janet Higuti. "Biodiversity of ostracod communities (Crustacea, Ostracoda) in a tropical floodplain". Inland Waters 7, n. 3 (3 luglio 2017): 323–32. http://dx.doi.org/10.1080/20442041.2017.1329913.
Testo completo
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Karanovic, I., e G. L. Pesce. "Martenscypridopsisa new ostracod genus (Crustacea : Ostracoda) from African inland waters". Annales de Limnologie - International Journal of Limnology 36, n. 3 (settembre 2000): 149–55. http://dx.doi.org/10.1051/limn/2000012.
Testo completo