Laurie M. Charrieau, L. Bryngemark, Ingemar Hansson, H. Filipsson
Abstract. Analyses of foraminiferal assemblages have often been implemented on dry samples, which are easy to split. In some cases, the wet-picking method is preferred as it allows the preservation of more foraminiferal forms and facilitates the picking of live foraminifera. However, the increased execution time needed for wet picking may cause micropalaeontologists to refrain from employing it in a routine way. Here we present an improved and cost-effective wet splitter (including a 3-D printing file) for micropalaeontological samples aimed to reduce picking time while keeping information loss to a minimum. We demonstrate small sample losses as well as statistical consistency across splits. We show that the time saved picking a subset will always be larger than the relative increase in statistical uncertainty.
{"title":"Improved wet splitter for micropalaeontological analysis, and assessment of uncertainty using data from splitters","authors":"Laurie M. Charrieau, L. Bryngemark, Ingemar Hansson, H. Filipsson","doi":"10.5194/JM-37-191-2018","DOIUrl":"https://doi.org/10.5194/JM-37-191-2018","url":null,"abstract":"Abstract. Analyses of foraminiferal assemblages have often been implemented on dry\u0000samples, which are easy to split. In some cases, the wet-picking method is\u0000preferred as it allows the preservation of more foraminiferal forms and\u0000facilitates the picking of live foraminifera. However, the increased\u0000execution time needed for wet picking may cause micropalaeontologists to\u0000refrain from employing it in a routine way. Here we present an improved and\u0000cost-effective wet splitter (including a 3-D printing file) for\u0000micropalaeontological samples aimed to reduce picking time while keeping\u0000information loss to a minimum. We demonstrate small sample losses as well as\u0000statistical consistency across splits. We show that the time saved picking a\u0000subset will always be larger than the relative increase in statistical\u0000uncertainty.","PeriodicalId":54786,"journal":{"name":"Journal of Micropalaeontology","volume":"37 1","pages":"191-194"},"PeriodicalIF":2.0,"publicationDate":"2018-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45872746","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Munef Mohammed, P. Frenzel, D. Keyser, F. Hussain, Abdulkareem Abood, Abdulmajed Sha'af, Sadham Alzara'e, Sakher Alammari
Abstract. Lake or marsh sediments in the Qa'a Jahran–Dhamār area indicate a period of higher moisture availability in the early Holocene of the highlands of Yemen. Forty-two marl–peat sediment samples from eight stratigraphic sections of that area have been collected and are examined for the first time for their ostracod associations. Eight species belonging to seven genera and four families are reported. Their ecological tolerances and preferences are used to investigate the climatic and environmental changes in the early to mid-Holocene. Our data are compared and correlated with previous archaeological results, particularly from the region of Qa'a Jahran (Dhamār) in the vicinity of the village of Beyt Nahmi. We conclude that the wettest period of the Holocene was from about 7900 to 7400 cal yr BP, when northwards incursion of the Indian Ocean Monsoon caused intensified monsoon precipitation over southern Arabia.
摘要Qa’a Jahran–Dhamār地区的湖泊或沼泽沉积物表明，在也门高地的全新世早期，有一段时期的水分利用率较高。从该地区的八个地层剖面中采集了四十二个泥灰岩-泥炭沉积物样本，并首次对其介形虫组合进行了检查。报道了四科七属八种。它们的生态耐受性和偏好被用来研究全新世早期的气候和环境变化。我们的数据与以前的考古结果进行了比较和关联，特别是来自Beyt Nahmi村附近的Qa’a Jahran（Dhamār）地区的考古结果。我们得出的结论是，全新世最潮湿的时期约为7900年至7400年 cal 年 当印度洋季风向北入侵导致阿拉伯南部季风降水加剧时，英国石油公司。
{"title":"A humid early Holocene in Yemen interpreted from palaeoecology and taxonomy of freshwater ostracods","authors":"Munef Mohammed, P. Frenzel, D. Keyser, F. Hussain, Abdulkareem Abood, Abdulmajed Sha'af, Sadham Alzara'e, Sakher Alammari","doi":"10.5194/JM-37-167-2018","DOIUrl":"https://doi.org/10.5194/JM-37-167-2018","url":null,"abstract":"Abstract. Lake or marsh sediments in the Qa'a Jahran–Dhamār area indicate a period of\u0000higher moisture availability in the early Holocene of the highlands of Yemen.\u0000Forty-two marl–peat sediment samples from eight stratigraphic sections of\u0000that area have been collected and are examined for the first time for their\u0000ostracod associations. Eight species belonging to seven genera and four\u0000families are reported. Their ecological tolerances and preferences are used\u0000to investigate the climatic and environmental changes in the early to\u0000mid-Holocene. Our data are compared and correlated with previous\u0000archaeological results, particularly from the region of Qa'a Jahran (Dhamār)\u0000in the vicinity of the village of Beyt Nahmi. We conclude that the wettest\u0000period of the Holocene was from about 7900 to 7400 cal yr BP, when\u0000northwards incursion of the Indian Ocean Monsoon caused intensified monsoon\u0000precipitation over southern Arabia.","PeriodicalId":54786,"journal":{"name":"Journal of Micropalaeontology","volume":"37 1","pages":"167-180"},"PeriodicalIF":2.0,"publicationDate":"2018-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47459215","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract. We report the occurrence of an Ammobaculoides-dominated assemblage in the lowermost member of the Middle Jurassic Dhruma Formation exposed west of Riyadh, Saudi Arabia. The new species Ammobaculoides dhrumaensis n.sp. is described from the green shale of the D1 unit (also known as the Balum Member) of the Dhruma Formation, which has been assigned an early Bajocian age based on ammonites. Our new finding constitutes the oldest reported worldwide occurrence of the agglutinated foraminiferal genus Ammobaculoides Plummer, 1932.
{"title":"The occurrence of a shallow-water Ammobaculoides assemblage in the Middle Jurassic (Bajocian) Dhruma Formation of Central Saudi Arabia","authors":"M. Kaminski, M. H. Malik, E. Setoyama","doi":"10.5194/JM-37-149-2018","DOIUrl":"https://doi.org/10.5194/JM-37-149-2018","url":null,"abstract":"Abstract. We report the occurrence of an Ammobaculoides-dominated assemblage in the lowermost member of the Middle Jurassic Dhruma Formation exposed west of Riyadh, Saudi Arabia. The new species Ammobaculoides dhrumaensis n.sp. is described from the green shale of the D1 unit (also known as the Balum Member) of the Dhruma Formation, which has been assigned an early Bajocian age based on ammonites. Our new finding constitutes the oldest reported worldwide occurrence of the agglutinated foraminiferal genus Ammobaculoides Plummer, 1932.","PeriodicalId":54786,"journal":{"name":"Journal of Micropalaeontology","volume":"37 1","pages":"149-152"},"PeriodicalIF":2.0,"publicationDate":"2018-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44103440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract. The paper presents Miocene (lower Sarmatian) benthic foraminifera from the FH 3 P 1 Rădăuţi Core section from the northwestern part of the Moldavian Platform, Romania. Based on foraminiferal assemblages we infer sediments were deposited in shallow-water, including marine-marginal environments, of varying salinities from brackish to normal marine with some short and rather small sea-level changes. Moreover, we describe for the first time in the Moldavian Platform a very rare species, Miliolina cristata Millett, which presents a characteristic spinose keel. Based on a detailed study of the test morphology and its variability, observed in picked material as well as in thin sections, we discuss some palaeoecological aspects of these foraminifera. M. cristata probably does not constitute a distinctive species, but it is more probable that some miliolid taxa developed such an exoskeletal feature in response to new environmental conditions, such as more turbulent water. Accordingly, our study would support the thesis that one of the functions of the benthic foraminiferal spines is to stabilize foraminiferal tests found in sandy substrates from high-energy environments.
{"title":"The functional significance of the spinose keel structure of benthic foraminifera: inferences from Miliolina cristata Millett, 1898 (Miliolida) from northeast Romania","authors":"S. Dumitriu, Zofia Dubicka, Viorel Ionesi","doi":"10.5194/JM-37-153-2018","DOIUrl":"https://doi.org/10.5194/JM-37-153-2018","url":null,"abstract":"Abstract. The paper presents Miocene (lower Sarmatian) benthic foraminifera from the\u0000FH 3 P 1 Rădăuţi Core section from the northwestern part\u0000of the Moldavian Platform, Romania. Based on foraminiferal assemblages we\u0000infer sediments were deposited in shallow-water, including marine-marginal\u0000environments, of varying salinities from brackish to normal marine with some\u0000short and rather small sea-level changes. Moreover, we describe for the first\u0000time in the Moldavian Platform a very rare species, Miliolina cristata Millett, which presents a characteristic spinose keel. Based on a\u0000detailed study of the test morphology and its variability, observed in picked\u0000material as well as in thin sections, we discuss some palaeoecological\u0000aspects of these foraminifera. M. cristata probably does not\u0000constitute a distinctive species, but it is more probable that some miliolid\u0000taxa developed such an exoskeletal feature in response to new environmental\u0000conditions, such as more turbulent water. Accordingly, our study would\u0000support the thesis that one of the functions of the benthic foraminiferal\u0000spines is to stabilize foraminiferal tests found in sandy substrates from\u0000high-energy environments.","PeriodicalId":54786,"journal":{"name":"Journal of Micropalaeontology","volume":"37 1","pages":"153-166"},"PeriodicalIF":2.0,"publicationDate":"2018-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47855618","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract. Beautifully preserved dinoflagellate cysts continue to be discovered in UK Cretaceous chalks and provide important new biostratigraphic information. Five new species – Conosphaeridium norfolkense sp. nov., Glaphyrocysta coniacia sp. nov., Impletosphaeridium banterwickense sp. nov., Sentusidinium devonense sp. nov., Sentusidinium spinosum sp. nov. and the new subspecies Spiniferites ramosus subsp. ginakrogiae subsp. nov. – are described from Upper Cretaceous strata of the British Geological Survey (BGS) Banterwick Barn and Trunch boreholes (onshore UK). An emended diagnosis for Odontochitina diducta Pearce is also provided to broaden the morphological variability in the type material.
{"title":"Additional new organic-walled dinoflagellate cysts from two onshore UK Chalk boreholes","authors":"M. Pearce","doi":"10.5194/JM-37-73-2018","DOIUrl":"https://doi.org/10.5194/JM-37-73-2018","url":null,"abstract":"Abstract. Beautifully preserved dinoflagellate cysts continue to be discovered in UK\u0000Cretaceous chalks and provide important new biostratigraphic information.\u0000Five new species – Conosphaeridium norfolkense sp. nov.,\u0000 Glaphyrocysta coniacia sp. nov.,\u0000 Impletosphaeridium banterwickense sp. nov.,\u0000 Sentusidinium devonense sp. nov., Sentusidinium spinosum sp. nov. and the new subspecies Spiniferites ramosus subsp. ginakrogiae subsp. nov. – are described from\u0000Upper Cretaceous strata of the British Geological Survey (BGS) Banterwick\u0000Barn and Trunch boreholes (onshore UK). An emended diagnosis for\u0000 Odontochitina diducta Pearce is also provided to broaden\u0000the morphological variability in the type material.","PeriodicalId":54786,"journal":{"name":"Journal of Micropalaeontology","volume":"37 1","pages":"73-86"},"PeriodicalIF":2.0,"publicationDate":"2018-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48515997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
P. Bijl, A. Houben, A.M.J. Bruls, J. Pross, F. Sangiorgi
Abstract. There is growing interest in the scientific community in reconstructing the paleoceanography of the Southern Ocean during the Oligocene–Miocene because these time intervals experienced atmospheric CO2 concentrations with relevance to our future. However, it has remained notoriously difficult to put the sedimentary archives used in these efforts into a temporal framework. This is at least partially due to the fact that the bio-events recorded in organic-walled dinoflagellate cysts (dinocysts), which often represent the only microfossil group preserved, have not yet been calibrated to the international timescale. Here we present dinocyst ranges from Oligocene–Miocene sediments drilled offshore the Wilkes Land continental margin, East Antarctica (Integrated Ocean Drilling Program (IODP) Hole U1356A). In addition, we apply statistical means to test a priori assumptions about whether the recorded taxa were deposited in situ or were reworked from older strata. Moreover, we describe two new dinocyst species, Selenopemphix brinkhuisii sp. nov. and Lejeunecysta adeliensis sp. nov., which are identified as important markers for regional stratigraphic analysis. Finally, we calibrate all identified dinocyst events to the international timescale using independent age control from calcareous nanoplankton and magnetostratigraphy from IODP Hole U1356A, and we propose a provisional dinoflagellate cyst zonation scheme for the Oligocene–Miocene of the Southern Ocean.
{"title":"Stratigraphic calibration of Oligocene–Miocene organic-walled dinoflagellate cysts from offshore Wilkes Land, East Antarctica, and a zonation proposal","authors":"P. Bijl, A. Houben, A.M.J. Bruls, J. Pross, F. Sangiorgi","doi":"10.5194/JM-37-105-2018","DOIUrl":"https://doi.org/10.5194/JM-37-105-2018","url":null,"abstract":"Abstract. There is growing interest in the scientific community in reconstructing the paleoceanography of the Southern Ocean during the Oligocene–Miocene because these time intervals experienced atmospheric CO2 concentrations with relevance to our future. However, it has remained notoriously difficult to put the sedimentary archives used in these efforts into a temporal framework. This is at least partially due to the fact that the bio-events recorded in organic-walled dinoflagellate cysts (dinocysts), which often represent the only microfossil group preserved, have not yet been calibrated to the international timescale. Here we present dinocyst ranges from Oligocene–Miocene sediments drilled offshore the Wilkes Land continental margin, East Antarctica (Integrated Ocean Drilling Program (IODP) Hole U1356A). In addition, we apply statistical means to test a priori assumptions about whether the recorded taxa were deposited in situ or were reworked from older strata. Moreover, we describe two new dinocyst species, Selenopemphix brinkhuisii sp. nov. and Lejeunecysta adeliensis sp. nov., which are identified as important markers for regional stratigraphic analysis. Finally, we calibrate all identified dinocyst events to the international timescale using independent age control from calcareous nanoplankton and magnetostratigraphy from IODP Hole U1356A, and we propose a provisional dinoflagellate cyst zonation scheme for the Oligocene–Miocene of the Southern Ocean.","PeriodicalId":54786,"journal":{"name":"Journal of Micropalaeontology","volume":"37 1","pages":"105-138"},"PeriodicalIF":2.0,"publicationDate":"2018-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43451963","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract. The multi-element apparatus of the Middle Triassic conodont Neogondolella ex gr. regalis has been reconstructed based on material collected from the upper Anisian in British Columbia, Canada. The apparatus of this species group is distinguished by the presence of a segminiplanate P1 element with a high, fused carina, and an alate S0 element with anterior processes that bifurcate at the cusp. This S0 element morphology is unlike those of other species from the upper Anisian of North America, but similar to those from the Lower Triassic. The new reconstruction demonstrates that Neogondolella ex gr. regalis does not belong to the genus Neogondolella, nor to any other Triassic gondolellid genus. It is therefore proposed that Neogondolella ex gr. regalis should be referred to a new genus.
摘要以加拿大不列颠哥伦比亚省上阿尼西统的资料为基础，重建了中三叠统牙状齿neogondolella ex r. regalis的多元素仪器。这个物种群的器官的特点是具有高的融合隆突的半平面P1元件和具有在尖端分叉的前突的形位50元件的存在。这种S0元素的形态与北美上三叠统的其他物种不同，但与下三叠统的物种相似。新的重建表明，Neogondolella ex gr. regalis不属于Neogondolella属，也不属于任何其他三叠纪gondolellid属。因此，我们认为新贡多拉菌是一种很好的细菌。帝王蝶属应归入一个新属。
{"title":"Reconstruction of the multielement apparatus of Neogondolella ex gr. regalis Mosher, 1970 (Conodonta) from the Anisian (Middle Triassic) in British Columbia, Canada","authors":"M. Golding","doi":"10.5194/JM-37-21-2018","DOIUrl":"https://doi.org/10.5194/JM-37-21-2018","url":null,"abstract":"Abstract. The multi-element apparatus of the Middle Triassic conodont\u0000Neogondolella ex gr. regalis has been reconstructed based\u0000on material collected from the upper Anisian in British Columbia, Canada. The\u0000apparatus of this species group is distinguished by the presence of a\u0000segminiplanate P1 element with a high, fused carina, and an alate S0 element\u0000with anterior processes that bifurcate at the cusp. This S0 element\u0000morphology is unlike those of other species from the upper Anisian of North\u0000America, but similar to those from the Lower Triassic. The new reconstruction\u0000demonstrates that Neogondolella ex gr. regalis does not\u0000belong to the genus Neogondolella, nor to any other Triassic\u0000gondolellid genus. It is therefore proposed that Neogondolella ex\u0000gr. regalis should be referred to a new genus.","PeriodicalId":54786,"journal":{"name":"Journal of Micropalaeontology","volume":"37 1","pages":"21-24"},"PeriodicalIF":2.0,"publicationDate":"2018-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47621012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract. Oligosphaeridium is a gonyaulacacean dinocyst lacking cingular processes and possessing a distinctive process centred on the antapical plate indicating a sexiform hyposomal tabulation. However, specimens referable to the description of Oligosphaeridium prolixispinosum Davey and Williams, 1966, although lacking cingular processes, are clearly not sexiform. As an additional complication, the holotype of Oligosphaeridium prolixispinosum possesses cingular processes. In this brief contribution, we describe the new genus Fetchamium to accommodate the new transfer Fetchamium prolixispinosum gen. et comb. nov. and provide a discussion and emended diagnosis of the species.
{"title":"Fetchamium prolixispinosum gen. et comb. nov. (division Dinoflagellata)","authors":"Martin A. Pearce, Graham L. Williams","doi":"10.5194/JM-37-17-2018","DOIUrl":"https://doi.org/10.5194/JM-37-17-2018","url":null,"abstract":"Abstract. Oligosphaeridium is a gonyaulacacean dinocyst lacking cingular processes and possessing a\u0000distinctive process centred on the antapical plate indicating a sexiform\u0000hyposomal tabulation. However, specimens referable to the description of\u0000Oligosphaeridium prolixispinosum Davey and Williams, 1966, although lacking cingular processes, are clearly\u0000not sexiform. As an additional complication, the holotype of\u0000Oligosphaeridium prolixispinosum possesses cingular processes. In this brief contribution, we describe the\u0000new genus Fetchamium to accommodate the new transfer Fetchamium prolixispinosum gen. et comb. nov. and provide a\u0000discussion and emended diagnosis of the species.","PeriodicalId":54786,"journal":{"name":"Journal of Micropalaeontology","volume":"37 1","pages":"17-20"},"PeriodicalIF":2.0,"publicationDate":"2018-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46694407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Yasuhara, Kamila Sztybor, T. L. Rasmussen, Hisayo Okahashi, Runa Sato, H. Tanaka
Abstract. Despite their high abundance and diversity, microfossil taxa adapted to a particular chemosynthetic environment have rarely been studied and are therefore poorly known. Here we report on an ostracod species, Rosaliella svalbardensis gen. et sp. nov., from a cold methane seep site at the western Svalbard margin, Fram Strait. The new species shows a distinct morphology, different from other eucytherurine ostracod genera. It has a marked similarity to Xylocythere, an ostracod genus known from chemosynthetic environments of wood falls and hydrothermal vents. Rosaliella svalbardensis is probably an endemic species or genus linked to methane seeps. We speculate that the surface ornamentation of pore clusters, secondary reticulation, and pit clusters may be related to ectosymbiosis with chemoautotrophic bacteria. This new discovery of specialized microfossil taxa is important because they can be used as an indicator species for past and present seep environments ( http://zoobank.org/urn:lsid:zoobank.org:pub:6075FF30-29D5-4DAB-9141-AE722CD3A69B ).
{"title":"Cold-seep ostracods from the western Svalbard margin: direct palaeo-indicator for methane seepage?","authors":"M. Yasuhara, Kamila Sztybor, T. L. Rasmussen, Hisayo Okahashi, Runa Sato, H. Tanaka","doi":"10.5194/JM-37-139-2018","DOIUrl":"https://doi.org/10.5194/JM-37-139-2018","url":null,"abstract":"Abstract. Despite their high abundance and diversity, microfossil taxa adapted to a particular chemosynthetic environment have rarely been studied and are therefore poorly known. Here we report on an ostracod species, Rosaliella svalbardensis gen. et sp. nov., from a cold methane seep site at the western Svalbard margin, Fram Strait. The new species shows a distinct morphology, different from other eucytherurine ostracod genera. It has a marked similarity to Xylocythere, an ostracod genus known from chemosynthetic environments of wood falls and hydrothermal vents. Rosaliella svalbardensis is probably an endemic species or genus linked to methane seeps. We speculate that the surface ornamentation of pore clusters, secondary reticulation, and pit clusters may be related to ectosymbiosis with chemoautotrophic bacteria. This new discovery of specialized microfossil taxa is important because they can be used as an indicator species for past and present seep environments ( http://zoobank.org/urn:lsid:zoobank.org:pub:6075FF30-29D5-4DAB-9141-AE722CD3A69B ).","PeriodicalId":54786,"journal":{"name":"Journal of Micropalaeontology","volume":"37 1","pages":"139-148"},"PeriodicalIF":2.0,"publicationDate":"2018-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42038616","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
P. Pearson, Iodp Expedition Shipboard ScientificParty
Abstract. Agglutinated foraminifera are marine protists that show apparently complex behaviour in constructing their shells, involving selecting suitable sedimentary grains from their environment, manipulating them in three dimensions, and cementing them precisely into position. Here we illustrate a striking and previously undescribed example of complex organisation in fragments of a tube-like foraminifer (questionably assigned to Rhabdammina) from 1466 m water depth on the northwest Australian margin. The tube is constructed from well-cemented siliciclastic grains which form a matrix into which hundreds of planktonic foraminifer shells are regularly spaced in apparently helical bands. These shells are of a single species, Turborotalita clarkei, which has been selected to the exclusion of all other bioclasts. The majority of shells are set horizontally in the matrix with the umbilical side upward. This mode of construction, as is the case with other agglutinated tests, seems to require either an extraordinarily selective trial-and-error process at the site of cementation or an active sensory and decision-making system within the cell.
{"title":"A deep-sea agglutinated foraminifer tube constructed with planktonic foraminifer shells of a single species","authors":"P. Pearson, Iodp Expedition Shipboard ScientificParty","doi":"10.5194/JM-37-97-2018","DOIUrl":"https://doi.org/10.5194/JM-37-97-2018","url":null,"abstract":"Abstract. Agglutinated foraminifera are marine protists that show apparently complex\u0000behaviour in constructing their shells, involving selecting suitable\u0000sedimentary grains from their environment, manipulating them in three\u0000dimensions, and cementing them precisely into position. Here we illustrate a\u0000striking and previously undescribed example of complex organisation in\u0000fragments of a tube-like foraminifer (questionably assigned to\u0000Rhabdammina) from 1466 m water depth on the northwest Australian\u0000margin. The tube is constructed from well-cemented siliciclastic grains which\u0000form a matrix into which hundreds of planktonic foraminifer shells are\u0000regularly spaced in apparently helical bands. These shells are of a single\u0000species, Turborotalita clarkei, which has been selected to the\u0000exclusion of all other bioclasts. The majority of shells are set horizontally\u0000in the matrix with the umbilical side upward. This mode of construction, as\u0000is the case with other agglutinated tests, seems to\u0000require either an extraordinarily\u0000selective trial-and-error process at the site of cementation or an active\u0000sensory and decision-making system within the cell.","PeriodicalId":54786,"journal":{"name":"Journal of Micropalaeontology","volume":"37 1","pages":"97-104"},"PeriodicalIF":2.0,"publicationDate":"2018-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48140363","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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