REVUE DE MICROPALEONTOLOGIE最新文献

{"title":"Time-spatial boundaries of bioecozonations (planktonic foraminifera) in the latest Quaternary: a case study from the western South Atlantic","authors":"Jaime Yesid Suárez-Ibarra , Sandro Monticelli Petró , Cristiane Fraga Frozza , Tiago Menezes Freire , Rodrigo Da Costa Portilho-Ramos , María Alejandra Gómez Pivel","doi":"10.1016/j.revmic.2021.100554","DOIUrl":"10.1016/j.revmic.2021.100554","url":null,"abstract":"<div><p>Planktonic foraminifera assemblages accurately record climate fluctuations that occurred during the Quaternary. These assemblage variations (frequently abundance changes) are widely used to establish bioecozones. Since climate variations are neither synchronous nor spatially homogenous, this paper assesses the application of the bioecozonations from the south Brazilian continental margin to its understudied southern extreme. To accomplish this purpose, census counts were made on core SAT-048A, retrieved from the continental slope of the southern extreme, and were compared to published records from the south Brazilian continental margin. According to the age model, the sediment core SAT-048A spans the last 42 kyr. The last reappearance of the <em>Globorotalia menardii</em> complex is dated for the first time in the Pelotas Basin at 8.5 ka, marking the biochronologic limit of bioecozones Y/Z. The last disappearance of <em>Pulleniatina</em> spp., marker of the sub-bioecozones Y2/Y1, is dated at 25.7 ka<em>,</em> showing an asynchronous characteristic already reported for the Caribbean and Equatorial Atlantic, meanwhile, its last reappearance, that marks the Y1B/Y1A limit, is dated at 15.5 ka, agreeing with previous studies. The Pleistocene/Holocene boundary can be recognized based on the Last Abundance Peak of the <em>Globorotalia truncatulinoides</em> dextral morphotype (<em>Gt</em>dLAP), also recognized in other cores of the south Brazilian continental margin.</p><p><strong>Resumé</strong></p><p>Les assemblages de foraminifères planctoniques ont enregistré avec précision les fluctuations climatiques qui se sont produites au cours du Quaternaire. Ces variations d'assemblages (souvent des changements d'abondance) sont largement utilisées pour établir des bioécozones. Puisque les variations climatiques ne sont ni synchrones ni spatialement homogènes, cet article évalue l'application des bioécozonations sur la marge continentale sud du Brésil jusqu’à son extrême sud, sous-étudié. Pour atteindre cet objectif, des comptages ont été effectués sur le carotte SAT-048A, prélevée sur le talus continental de l'extrême sud, et ont été comparés aux enregistrements publiés de la marge continentale sud du Brésil. Selon le modèle d'âge, la carotte de sédiments SAT-048A a enregistré les 42 derniers kyr. La dernière réapparition du complexe <em>Globorotalia menardii</em> est datée pour la première fois dans le Bassin de Pelotas à 8,5 ka, marquant la limite biochronologique des bioécozones Y/Z. La dernière disparition de <em>Pulleniatina</em> spp., marqueur des sous-bioécozones Y2/Y1, est datée à 25,7 ka, montrant une caractéristique asynchrone déjà signalée pour les Caraïbes et l'Atlantique équatorial, en attendant, sa dernière réapparition, qui marque la limite Y1B/Y1A, est datée de 15,5 ka, en accord avec les études précédentes. La limite Pléistocène/Holocène peut être reconnue sur la base du dernier pic d'abondance du morphotype dextral <em>Globorotalia t","PeriodicalId":45442,"journal":{"name":"REVUE DE MICROPALEONTOLOGIE","volume":"73 ","pages":"Article 100554"},"PeriodicalIF":0.9,"publicationDate":"2021-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120867788","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Additional taxonomic data on late Messinian ostracods from Eastern Tunisia","authors":"Francesco Sciuto ,&nbsp;Rim Temani ,&nbsp;Hayet Khayati Ammar","doi":"10.1016/j.revmic.2021.100604","DOIUrl":"10.1016/j.revmic.2021.100604","url":null,"abstract":"<div><p><span>The ostracod<span> fauna of two late Messinian stratigraphic sections in eastern Tunisia have been analysed. The first section (Salakta-SAL section), is located south of Cape Bon, the second (Wadi el Kebir–OK section) in the Sahel region. In both sections the shallow marine ostracod fauna is dominant but have also been found taxa referable to the Lago Mare facies. From the shallow water marine levels, several ostracods taxa were recognized; some of which, due to their morphological particularities, have been described as new species. In a first contribution (Sciuto </span></span><em>et al</em>., 2021) have been described twenty-four taxa. Now, a second series of sixty shallow water marine ostracod taxa coming from the sedimentary levels of the Oued El Bir Formation, considered unknown or little known until now are systematically listed below, described and illustrated. They belong to the genera <em>Cytherella, Bairdia, Cushmanidea, Cytheridea, Cyamocytheridea, Miocyprideis, Aurila, Cimbaurila, Peteraurila, Urocythere, Callistocythere</em>, <em>Leptocythere, Mediocytherideis</em>, <em>Loxoconcha, Loxoconchissa, Sagmatocythere, Neomonoceratina, Carinocythereis, Chrysocythere, Cistacythereis, Keijella, Mutilus, Neocytheretta, Okadaleberis, Verrucocythereis, Cytheretta, Xestoleberis.</em></p></div>","PeriodicalId":45442,"journal":{"name":"REVUE DE MICROPALEONTOLOGIE","volume":"73 ","pages":"Article 100604"},"PeriodicalIF":0.9,"publicationDate":"2021-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114241220","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Radiolarian evidence for Middle Bathonian radiolarites in the Episkopi Formation (Ayios Photios Group, Mamonia Complex, SW Cyprus).","authors":"Antriani Varnava ,&nbsp;Taniel Danelian ,&nbsp;Sylvie Regnier ,&nbsp;Léa Devaere","doi":"10.1016/j.revmic.2021.100549","DOIUrl":"10.1016/j.revmic.2021.100549","url":null,"abstract":"<div><p><span><span>The Ayios Photios Group in SW Cyprus represents a deep-water slope or base of slope sequence that was accumulated on a Mesozoic margin of the Mediterranean Tethys. The Episkopi Formation is an essentially radiolaritic sequence, the age of which was previously considered to range between the </span>Callovian<span><span> and the Valanginian<span>. A moderately well preserved (PI 4-5) radiolarian assemblage was extracted after laboratory leaching with diluted </span></span>hydrofluoric acid<span> of a radiolarian chert bed south of the village of Episkopi. Based on the co-occurrence of </span></span></span><em>Bernoullius rectispinus leporinus</em> Conti &amp; Marcucci, <em>Hexasaturnalis tetraspinus</em> (Yao) and <em>Theocapsommella cucurbiformis</em><span> (Baumgartner), the assemblage is correlated with the Middle Bathonian<span> (Unitary Association Zone 6). Our results extend downwards the known age range of radiolarites of the Episkopi formation and reduce the previously known range of depositional hiatus with the underlying Upper Triassic formations of the Ayios Photios Group.</span></span></p></div>","PeriodicalId":45442,"journal":{"name":"REVUE DE MICROPALEONTOLOGIE","volume":"73 ","pages":"Article 100549"},"PeriodicalIF":0.9,"publicationDate":"2021-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126598708","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Benthic foraminiferal morphogroups of Middle to Late Jurassic succession of Jhurio Dome, Kutch, Gujarat, India: Palaeoenvironmental implications","authors":"Ainul H. Ansari ,&nbsp;Abu Talib ,&nbsp;Avneet Kumar","doi":"10.1016/j.revmic.2021.100555","DOIUrl":"10.1016/j.revmic.2021.100555","url":null,"abstract":"&lt;div&gt;&lt;p&gt;The analysis of the benthic foraminiferal assemblages recovered from the Jurassic sequence exposed at Jhurio Dome, Kutch, reveals the presence of six types of major morphogroups, some of them subdivided into subgroups. Changes in benthic foraminiferal morphogroups, including life habitat (from epifaunal to deep infaunal) and nutritional behaviour (from herbivores to omnivores, suspension-feeders to bacterial scavengers and detritivores to primary weed fauna) are mainly influenced by fluctuations in nutrient flux, oxygen availability, salinity&lt;span&gt; and bathymetry and are reliable indicators to interpret palaeoenvironmental fluctuations during the deposition of the sediments.&lt;/span&gt;&lt;/p&gt;&lt;p&gt;The Middle to Upper Jurassic sequence of Jhurio Dome is subdivided into four palaeoecological intervals on the basis of benthic foraminiferal morphogroup associations. Deposition in Palaeoecological interval I commenced with a transgressive phase in the outer shelf region with normal salinity as well as high oxygen and nutrient availability. Palaeoecological interval II witnessed fluctuating hyposaline conditions, depleted oxygen and low nutrient availability in a regressive episode in the middle shelf environment. Palaeoecological interval III is considered to have been deposited in a transgressive phase in the deepest part of the outer shelf with high salinity, increased levels of oxygen and nutrient flux. Palaeoecological interval IV, representing the upper part of the studied sequence is characterised by normal salinity, decreased oxygen levels, and high nutrient influx in a regressive middle shelf environment. The morphogroup analysis shows that, during the deposition of the analysed stratigraphic intervals, the environmental conditions at the sediment depositional site did not remain stable as indicated by the fluctuating shoreline on a tectonically rather unstable oceanic shelf.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Resumé&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;L'analyse des assemblages de foraminifères benthiques récupérés sur la séquence jurassique affleurant à Jhurio Dome, Kutch révèle la présence de six types de morphogroupes majeurs, certains d'entre eux subdivisés en sous-groupes. Les changements dans les morphogroupes des foraminifères benthiques, y compris l'habitat de vie (de l'épifaune à l'endofaune profonde) et le comportement nutritionnel (des herbivores aux omnivores, des suspensivores aux charognards bactériens et des détritivores à la faune primaire herbivore) sont principalement influencés par les fluctuations du flux de nutriments, la disponibilité en oxygène, la salinité et bathymétrie et sont des indicateurs fiables pour interpréter les fluctuations paléoenvironnementales lors du dépôt des sédiments.&lt;/p&gt;&lt;p&gt;La séquence du Jurassique moyen à supérieur de Jhurio Dome est subdivisée en quatre intervalles paléoécologiques sur la base d'associations de morphogroupes de foraminifères benthiques. Le dépôt dans l'intervalle paléoécologique I a commencé par une phase transgressive dans ","PeriodicalId":45442,"journal":{"name":"REVUE DE MICROPALEONTOLOGIE","volume":"73 ","pages":"Article 100555"},"PeriodicalIF":0.9,"publicationDate":"2021-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133717605","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sedimentology and Calcareous Nannofossil Biostratigraphy of Alaka Well, Niger Delta, Nigeria","authors":"Ndubuisi Ukpabi ,&nbsp;Kachikwulu Kingsley Okeke ,&nbsp;Mohamed Abioui","doi":"10.1016/j.revmic.2021.100529","DOIUrl":"10.1016/j.revmic.2021.100529","url":null,"abstract":"<div><p><span><span>Calcareous nannofossil<span> biostratigraphy of Alaka well was carried out to identify the biohorizons that exist, ultimately for </span></span>biozonation<span><span><span>, chronostratigraphy and geologic age calibration of the studied interval. The study involved </span>sedimentology<span> analysis, gamma ray description and preparation of two hundred and twelve (212) ditch cuttings, sampled at 9.144m intervals for the study of calcareous nannofossils on smear slides. Sedimentology and gamma ray analyse showed deposition within shallow </span></span>marine paleoenvironments with alternating minor transgressions in a generally progradational delta setting, accounting for the low calcareous nannofossil occurrences. The calcareous nannofossil assemblages recovered from the slide preparations consist of fourteen (14) species, comprising nine (9) long ranged, non-stratigraphic significant forms and five (5) short ranged stratigraphic significant forms. The biohorizons identified included Base (B) occurrence of </span></span><em>Catinaster coalitus</em> at 3578m; <em>Discoaster hamatus</em> at 2874m; Top (T) occurrence of <em>Discoaster hamatus</em> at 2518m and Base absence (Ba) of <em>Reticulofenestra pseudoumbilicus</em> at 2280m. Other biohorizons included Top occurrence (T) of <em>Discoaster bollii</em> at 2435m and <em>Discoaster deflandrei</em> at 3578m respectively. The biohorizons defined boundaries between biozones and showed that the studied interval penetrated four biozones from CNM11 to CNM14 of Backman <em>et al</em><span><span>. (2012), NN7 to NN10 of Martini (1971) and CN5b to CN8a of Okada and Bukry (1980). The geologic age of the studied interval ranged between about 11.60 Ma within CNM11/NN7/CN5b zone to about 8.80 Ma within CNM14/NN10/CN8a zone, the standard chronostratigraphy lies within Tortonian stage. Two chronostratigraphic surfaces were mapped in the studied section and comprised one global maximum transgression at 3514m corresponding to 10.5 Ma maximum </span>flooding event, and one localized maximum transgression at 2847m corresponding to 9.5 Ma maximum flooding surface, separated by sea-level lowstand mapped at 3331m and corresponding to 10.35 Ma.</span></p></div>","PeriodicalId":45442,"journal":{"name":"REVUE DE MICROPALEONTOLOGIE","volume":"72 ","pages":"Article 100529"},"PeriodicalIF":0.9,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.revmic.2021.100529","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123885978","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recent ostracods (Crustacea) from the southwestern coast of Peninsular Thailand (Satun Province), Andaman Sea Ostracodes (Crustacea) récents de la côte sud-ouest de la péninsule de Thaïlande (Province de Satun), Mer d'Andaman","authors":"Marie-Béatrice Forel","doi":"10.1016/j.revmic.2021.100526","DOIUrl":"10.1016/j.revmic.2021.100526","url":null,"abstract":"<div><p>An inventory of 35 species of ostracods (Crustacea) recovered from sediment samples from a shallow embayment nearby the Mu Koh Phetra National Park in the southwestern coast of Peninsular Thailand, Andaman Sea is given. Most of the species are well-known from the Indo-Pacific area and some others are kept in open nomenclature or compared to already know species because because only few specimens were found. Several species may be new to science but have also to be kept in open nomenclature until new material is obtained. The very abundant specimens of this assemblage are mainly disarticulated valves. This contribution adds to our knowledge of the distribution of ostracods in the Andaman Sea and the degree of ostracod relationship between the Indonesian, Indian and West Pacific areas.</p></div><div><h3>Resumé</h3><p>Un inventaire de 35 espèces d'ostracodes (Crustacea) provenant de sédiments d'une baie peu profonde près du Parc National Mu Koh Phetra sur la côte sud-ouest de la péninsule de Thïlande, Mer d'Andaman, est donné. La plupart des espèces sont bien connues de la zone Indo-Pacifique et certaines sont conservées en nomenclature ouverte ou comparées à des espèces déjà connues en raison du faible nombre de spécimens collectés. Plusieurs espèces semblent nouvelles mais sont aussi conservées en nomenclature ouverte jusqu’à l'observation de nouveau matériel. Les très abondants spécimens qui composent cet assemblage sont principalement des valves désarticulées. Cette contribution accroit notre connaissance de la distribution des ostracodes dans la Mer d'Andaman et de la relation entre les ostracodes des zones indonésiennes, indiennes et ouest-pacifiques.</p></div>","PeriodicalId":45442,"journal":{"name":"REVUE DE MICROPALEONTOLOGIE","volume":"72 ","pages":"Article 100526"},"PeriodicalIF":0.9,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.revmic.2021.100526","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132581362","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The palynology of the Lower-Middle Jurassic transition of the North Caucasus (southwest Russian Federation), calibrated with index ammonites","authors":"Аnna A. Goryacheva ,&nbsp;Vasily V. Mitta ,&nbsp;James B. Riding","doi":"10.1016/j.revmic.2021.100517","DOIUrl":"10.1016/j.revmic.2021.100517","url":null,"abstract":"<div><p><span><span><span><span>Palynomorphs from the Toarcian and </span>Aalenian<span> Djigiat Formation of Karachay-Cherkessia in the Kuban River Basin (North Caucasus, southwest Russian Federation) are reported for the first time. Five samples carefully selected for their biostratigraphical content were studied to document the palynological assemblages. Four samples (1, 2, 3, 4) were collected from pieces of rock with key index ammonite specimens, and sample 5 comprises fragments of ammonite shells from a sideritic concretion. Three of these samples (4, 2 and 1) yielded relatively abundant and diverse aquatic </span></span>microplankton (acritarchs, </span>dinoflagellate cysts<span>, prasinophytes and zygnematalean algae) and terrestrial palynomorphs (pollen and spores); the remaining two samples (3 and 5) were less productive and contained fewer than 50 palynomorph specimens. The study of the dinoflagellate assemblages provided characteristic and key information. These are the uppermost Toarcian </span></span><em>Nannoceratopsis</em> Assemblage and the uppermost Toarcian to lowermost Aalenian <em>Parvocysta</em> Suite Assemblage. The former is overwhelmingly dominated by <em>Nannoceratopsis</em> with sparse numbers of the <em>Parvocysta</em> suite, and the latter yielded more diverse and common specimens of <em>Parvocysta</em> and its relatives. This is consistent with the hypothesis that the <em>Parvocysta</em> suite migrated from the Boreal Realm further south into Laurasia during the Toarcian. Certain dinoflagellate cysts such as <em>Mancodinium semitabulatum</em> and <em>Scriniocassis</em> spp., which are typical of Europe and much of Greater Laurasia are absent. Composition of the pollen and spores proved relatively out to be monotonous, and cannot be subdivided. However, in general, the composition of the assemblages of spores and pollen is consistent with the Toarcian–Aalenian transition.</p></div>","PeriodicalId":45442,"journal":{"name":"REVUE DE MICROPALEONTOLOGIE","volume":"72 ","pages":"Article 100517"},"PeriodicalIF":0.9,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.revmic.2021.100517","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122922384","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"VSI “Progress on radiolarian research: a selection of studies from InterRad XV, Niigata 2017”","authors":"Noritoshi Suzuki ,&nbsp;Atsushi Matsuoka ,&nbsp;Taniel Danelian","doi":"10.1016/j.revmic.2021.100527","DOIUrl":"https://doi.org/10.1016/j.revmic.2021.100527","url":null,"abstract":"","PeriodicalId":45442,"journal":{"name":"REVUE DE MICROPALEONTOLOGIE","volume":"72 ","pages":"Article 100527"},"PeriodicalIF":0.9,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.revmic.2021.100527","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"92106139","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dinoflagellate cyst assemblages of the Cunga - Quifangondo cenozoic formations in the Cabo São Brás section, Kwanza Basin (Angola): towards a first stratigraphic and paleoenvironmental interpretation","authors":"Z. Pereira ,&nbsp;M. Mendes ,&nbsp;C. Rodrigues ,&nbsp;N. Mulanda ,&nbsp;M. Cacama ,&nbsp;P.C. Nsungani","doi":"10.1016/j.revmic.2021.100516","DOIUrl":"https://doi.org/10.1016/j.revmic.2021.100516","url":null,"abstract":"<div><p><span>This work introduces one of the first palynostatigraphic study conducted on formations from the Eocene and overlying lowermost </span>Miocene successions (Cunga and Quifangondo formations) exposed in the Onshore Kwanza Basin, Angola.</p><p>To improve the Cunga and Quifangondo formations age, new biostratigraphic correlations and palaeoenvironmental interpretations based on qualitative and quantitative analyses of organic walled dinoflagellate cysts from sedimentary rocks sampled in the Cabo de São Brás section were obtained.</p><p>Those works have revealed that the Cunga Formation could be assigned to a middle Eocene - early Oligocene<span><span> age, with a palynomorph signature typical of outer neritic to oceanic environments (dominance of dinocysts with microforaminiferal linings and </span>radiolarian pyritized fragments).</span></p><p>The lower Quifangondo Formation could be assigned to late Oligocene (latest Chattian) - early Miocene (Aquitanian) ages. This assumption is based on the first occurrence of <em>Ectosphaeropsis burdigalensis,</em> and the last occurrence of <em>Deflandrea</em> spp. and <em>Chiropteridium galea.</em> Additionally, the <em>Chiropteridium, Distatodinium, Homotryblium, Hystrichokolpoma</em> and <em>Lingulodinium</em><span> acme endorses a latest Chattian-early Aquitanian age to these samples. The palynomorph signature of this unit reflects an outer neritic environment.</span></p><p>The latest Oligocene/early Miocene Quifangondo Formation overlaps unconformably on strata of the middle Eocene to early Oligocene Cunga Formation, pointing out a hiatus between the two units.</p></div>","PeriodicalId":45442,"journal":{"name":"REVUE DE MICROPALEONTOLOGIE","volume":"72 ","pages":"Article 100516"},"PeriodicalIF":0.9,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.revmic.2021.100516","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"92106138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ostracods like ghosts in their shells: input of X-ray computed tomography for taxonomy and taphonomy of Early Triassic Hollinella","authors":"Marie-Béatrice Forel ,&nbsp;Nathalie Poulet-Crovisier ,&nbsp;Lidija Korat","doi":"10.1016/j.revmic.2021.100528","DOIUrl":"10.1016/j.revmic.2021.100528","url":null,"abstract":"<div><p><span>Abundant ostracods of the genus </span><em>Hollinella</em><span><span> (Palaeocopida) have recently been described from the Early Triassic </span>siliciclastic deposits of the paralic Mide B section, Yunnan Province, South China. These weathered and delicate specimens are preserved on the surface of cracked sediments, often still partly buried and impossible to extract. A small piece of siliciclastic sediments with </span><em>Hollinella</em><span> specimens visible on the surface has been investigated by X-ray computed tomography (CT) to search for better preserved and possibly complete specimens still enclosed in the matrix. While surface observations led to the attribution of these specimens to </span><em>Hollinella panxiensis</em> Wang already known from other Permian-Triassic sections in South China, this non-destructive technique reveals distinctive characters that drive us to introduce the new species <em>Hollinella locula</em> Forel nov. sp. Certain previous identifications of <em>Hollinella panxiensis</em> are re-attributed to <em>Hollinella locula</em><span>. The taphonomic analysis of this material is refined and confirms the previous interpretation of a low energy thanatocoenosis. This investigation further highlights the strong implications of new imaging techniques in diverse fields of ostracodology, even in the absence of soft parts preservation.</span></p></div>","PeriodicalId":45442,"journal":{"name":"REVUE DE MICROPALEONTOLOGIE","volume":"72 ","pages":"Article 100528"},"PeriodicalIF":0.9,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.revmic.2021.100528","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122420340","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}