D. Altıner, S. Özkan-Altıner, S. G. Atasoy, N. Şahin
The name Paynita is proposed for a new dagmaritin genus from the upper Changhsingian (Permian) carbonates of the Southern Biofacies Belt in Turkey. Paynita permotaurica differs from its ancestor Paradagmarita monodi by a hook-shaped fold in the apertural flap terminating systematically against the inner surface of the septal wall to protect the opening from one chamber to the other. It is associated with several species of dagmaritins, belonging to Paradagmarita, Paradagmacrusta, Louisettita, Dagmarita, Danielita, and Bidagmarita. The overall analysis of dagmaritins reveals that the stratigraphic range of the group is from Wordian to Changhsingian. The revised chronostratigraphy in the type area of the genus Sengoerina indicates that this oldest dagmaritin was derived from Globivalvulina cyprica in the Wordian. The first occurrences of genera Dagmarita and Danielita postdate the first occurrence of Sengoerina in the Wordian. Paynita is the last evolutionary step of the Sengoerina-Dagmarita-Crescentia-Paradagmarita lineage characterized by a planar apertural flap whose structure practically remained unchanged during the process of evolution. Paynita is the first genus in this lineage displaying fold in the apertural flap similar to the evolution of Louisettita from Dagmarita.
{"title":"Paynita Permotaurica N. Gen., N. SP., and the Other Dagmaritin Foraminifera from the Changhsingian (Permian) of Southern Turkey: Review of Dagmaritin Phylogeny","authors":"D. Altıner, S. Özkan-Altıner, S. G. Atasoy, N. Şahin","doi":"10.2113/GSJFR.51.1.14","DOIUrl":"https://doi.org/10.2113/GSJFR.51.1.14","url":null,"abstract":"\u0000 The name Paynita is proposed for a new dagmaritin genus from the upper Changhsingian (Permian) carbonates of the Southern Biofacies Belt in Turkey. Paynita permotaurica differs from its ancestor Paradagmarita monodi by a hook-shaped fold in the apertural flap terminating systematically against the inner surface of the septal wall to protect the opening from one chamber to the other. It is associated with several species of dagmaritins, belonging to Paradagmarita, Paradagmacrusta, Louisettita, Dagmarita, Danielita, and Bidagmarita. The overall analysis of dagmaritins reveals that the stratigraphic range of the group is from Wordian to Changhsingian. The revised chronostratigraphy in the type area of the genus Sengoerina indicates that this oldest dagmaritin was derived from Globivalvulina cyprica in the Wordian. The first occurrences of genera Dagmarita and Danielita postdate the first occurrence of Sengoerina in the Wordian. Paynita is the last evolutionary step of the Sengoerina-Dagmarita-Crescentia-Paradagmarita lineage characterized by a planar apertural flap whose structure practically remained unchanged during the process of evolution. Paynita is the first genus in this lineage displaying fold in the apertural flap similar to the evolution of Louisettita from Dagmarita.","PeriodicalId":54832,"journal":{"name":"Journal of Foraminiferal Research","volume":"51 1","pages":"14-31"},"PeriodicalIF":1.1,"publicationDate":"2021-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48377269","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Austral planktonic foraminiferal assemblages from immediately above the Cretaceous/Paleogene (K/Pg) boundary at Ocean Drilling Program Hole 690C (Maud Rise, Weddell Sea) and International Ocean Drilling Program Hole U1514C (southeast Indian Ocean) show a much different record of post-extinction recovery than anywhere outside the circum-Antarctic region. Species of Woodringina and Parvularugoglobigerina, genera with well-documented evolutionary successions within the early Danian P0 and Pα biozones at tropical/subtropical and mid-latitude localities, are absent from southern high latitude sequences. This study proposes new criteria for biostratigraphic correlation of the lowermost Danian Antarctic Paleocene AP0 and AP1 Zones using stratophenetic observations from Scanning Electron Microscope images of lower Danian planktonic foraminifera at deep-sea sites in the southern South Atlantic and southern Indian Ocean. The small but distinctive species Turborotalita nikolasi (Koutsoukos) is a highly reliable index species for the lowermost Danian as it consistently occurs immediately above the K/Pg boundary at multiple southern high latitude sites, which is consistent with its distribution at middle and low latitudes. Also useful for cross-latitude correlation is Parasubbotina neanika n. sp., which first appears within the lowermost Danian worldwide. The geographic distribution of the New Zealand species Antarcticella pauciloculata (Jenkins) and Zeauvigerina waiparaensis (Jenkins), as well as Eoglobigerina maudrisensis n. sp. from just above the K/Pg in the southern South Atlantic and southern Indian Ocean, helps define the extent of the Austral Biogeographic Province and provides evidence for marine communication via marine seaways across Antarctica. While An. pauciloculata was previously considered a benthic species, new stable isotope evidence demonstrates that it lived a planktonic mode of life. It is possible this species evolved from a benthic ancestor and that the benthic to planktonic transition occurred through an intermediate tychopelagic lifestyle at a time when calcareous plankton were less abundant as a result of the terminal Cretaceous mass extinction.
{"title":"Planktonic Foraminiferal Endemism at Southern High Latitudes Following the Terminal Cretaceous Extinction","authors":"B. Huber, M. Petrizzo, K. MacLeod","doi":"10.2113/GSJFR.50.4.382","DOIUrl":"https://doi.org/10.2113/GSJFR.50.4.382","url":null,"abstract":"\u0000 Austral planktonic foraminiferal assemblages from immediately above the Cretaceous/Paleogene (K/Pg) boundary at Ocean Drilling Program Hole 690C (Maud Rise, Weddell Sea) and International Ocean Drilling Program Hole U1514C (southeast Indian Ocean) show a much different record of post-extinction recovery than anywhere outside the circum-Antarctic region. Species of Woodringina and Parvularugoglobigerina, genera with well-documented evolutionary successions within the early Danian P0 and Pα biozones at tropical/subtropical and mid-latitude localities, are absent from southern high latitude sequences. This study proposes new criteria for biostratigraphic correlation of the lowermost Danian Antarctic Paleocene AP0 and AP1 Zones using stratophenetic observations from Scanning Electron Microscope images of lower Danian planktonic foraminifera at deep-sea sites in the southern South Atlantic and southern Indian Ocean. The small but distinctive species Turborotalita nikolasi (Koutsoukos) is a highly reliable index species for the lowermost Danian as it consistently occurs immediately above the K/Pg boundary at multiple southern high latitude sites, which is consistent with its distribution at middle and low latitudes. Also useful for cross-latitude correlation is Parasubbotina neanika n. sp., which first appears within the lowermost Danian worldwide. The geographic distribution of the New Zealand species Antarcticella pauciloculata (Jenkins) and Zeauvigerina waiparaensis (Jenkins), as well as Eoglobigerina maudrisensis n. sp. from just above the K/Pg in the southern South Atlantic and southern Indian Ocean, helps define the extent of the Austral Biogeographic Province and provides evidence for marine communication via marine seaways across Antarctica. While An. pauciloculata was previously considered a benthic species, new stable isotope evidence demonstrates that it lived a planktonic mode of life. It is possible this species evolved from a benthic ancestor and that the benthic to planktonic transition occurred through an intermediate tychopelagic lifestyle at a time when calcareous plankton were less abundant as a result of the terminal Cretaceous mass extinction.","PeriodicalId":54832,"journal":{"name":"Journal of Foraminiferal Research","volume":"50 1","pages":"382-402"},"PeriodicalIF":1.1,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45739085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Phenacophragma oezeri n. sp. (phylum Foraminifera, family Mayncinidae) is described from the Albian shallow-marine limestones of the Geyik Daği area, Central Taurides, S Turkey. It is characterized by a lenticular, completely involute test with eight to nine wedge-shaped chambers in the last whorl rapidly increased in height and by an areal and small slit-like aperture. It occurs in benthic foraminiferal wackestone/packstone and grainstone microfacies with gastropods, rudists and dasycladalean algae, in association with mainly Protochrysalidina elongata, Pseudonummoloculina aurigerica, Pseudonummoloculina heimi, Mayncina bulgarica, Mesorbitolina gr. texana, Cuneolina sliteri, Cuneolina parva, Akcaya minuta, and Akcaya auruncensis. This new species differs from the type species Phenacophragma assurgens in having a completely involute and lenticular test with less numerous chambers in the last whorl. It can be distinguished from the accompanied Mayncina bulgarica by its more axially compressed lenticular shape and its wedge-shaped (rather than falciform) chambers.
Phenacophragma oezeri n. sp.(有孔虫门，有孔虫科)来自土耳其南部中部Taurides的Geyik Daği地区的Albian浅海石灰岩。它的特点是透镜状的，完全渐开线试验，在最后一个螺旋上有8到9个楔形室，高度迅速增加，有一个面积小的狭缝状孔径。它发生在底栖有孔虫微相/包岩和颗粒岩微相中，与腹足类、粗生藻类和浅生藻类共生，主要与Protochrysalidina elongata、Pseudonummoloculina aurigerica、Pseudonummoloculina heimi、Mayncina bulgarica、Mesorbitolina gr. texana、Cuneolina sliteri、Cuneolina parva、Akcaya minuta和Akcaya auruncensis共生。这个新种与模式种的不同之处在于在最后一个轮上有一个完全渐开线和透镜状的试验，室数较少。它可以通过其轴向压缩的透镜状形状和楔形(而不是镰状)腔室与伴随的宝格丽斑区分开来。
{"title":"Phenacophragma Oezeri N. SP., a Benthic Foraminifera from Albian Shallow Marine Carbonates of the Geyİk Daği Area (Southern Turkey)","authors":"Cemile Solak, K. Tasli","doi":"10.2113/gsjfr.50.4.373","DOIUrl":"https://doi.org/10.2113/gsjfr.50.4.373","url":null,"abstract":"\u0000 Phenacophragma oezeri n. sp. (phylum Foraminifera, family Mayncinidae) is described from the Albian shallow-marine limestones of the Geyik Daği area, Central Taurides, S Turkey. It is characterized by a lenticular, completely involute test with eight to nine wedge-shaped chambers in the last whorl rapidly increased in height and by an areal and small slit-like aperture. It occurs in benthic foraminiferal wackestone/packstone and grainstone microfacies with gastropods, rudists and dasycladalean algae, in association with mainly Protochrysalidina elongata, Pseudonummoloculina aurigerica, Pseudonummoloculina heimi, Mayncina bulgarica, Mesorbitolina gr. texana, Cuneolina sliteri, Cuneolina parva, Akcaya minuta, and Akcaya auruncensis. This new species differs from the type species Phenacophragma assurgens in having a completely involute and lenticular test with less numerous chambers in the last whorl. It can be distinguished from the accompanied Mayncina bulgarica by its more axially compressed lenticular shape and its wedge-shaped (rather than falciform) chambers.","PeriodicalId":54832,"journal":{"name":"Journal of Foraminiferal Research","volume":"50 1","pages":"373-381"},"PeriodicalIF":1.1,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48875094","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study explored the response to salinity of intertidal foraminiferal assemblages from the Yellow Sea by culturing them for 100 days at six constant salinity levels (17, 22, 27, 32, 37, and 42 psu) in laboratory microcosms with four replicates each. A total of 7,471 live (stained) foraminiferal specimens were obtained and analyzed. The diversity parameters of foraminiferal assemblages (species richness, Margalef index, Shannon-Wiener index, and Fisher's alpha) declined significantly when the salinity was increased or decreased from the field value, but foraminiferal abundance was highly resistant to salinity. In addition, salinity exerted different effects on foraminifera from different orders. Specifically, the proportion of species from Order Miliolida significantly increased whereas that of species from Order Rotaliida decreased with increasing salinity. High salinity-tolerant species Ammonia aomoriensis, Cribrononion gnythosuturatum, Ammonia tepida, and Quinqueloculina seminula could fill unoccupied ecological niches when the proportion of salinity-sensitive species has declined. Furthermore, our morphometric results showed that foraminiferal test size was significantly negatively correlated with salinity, and numerous abnormal specimens appeared in foraminiferal assemblages when salinity deviated from the field value. Our study revealed that intertidal foraminiferal assemblages had high adaptability at different salinities because of the existence of high salinity-tolerant dominant species. In addition, salinity variation can significantly alter foraminiferal morphology in test size and abnormality.
{"title":"Response of Intertidal Foraminiferal Assemblages to Salinity Changes in a Laboratory Culture Experiment","authors":"Meng Li, Y. Lei, Tiegang Li, Shuaishuai Dong","doi":"10.2113/gsjfr.50.4.319","DOIUrl":"https://doi.org/10.2113/gsjfr.50.4.319","url":null,"abstract":"\u0000 This study explored the response to salinity of intertidal foraminiferal assemblages from the Yellow Sea by culturing them for 100 days at six constant salinity levels (17, 22, 27, 32, 37, and 42 psu) in laboratory microcosms with four replicates each. A total of 7,471 live (stained) foraminiferal specimens were obtained and analyzed. The diversity parameters of foraminiferal assemblages (species richness, Margalef index, Shannon-Wiener index, and Fisher's alpha) declined significantly when the salinity was increased or decreased from the field value, but foraminiferal abundance was highly resistant to salinity. In addition, salinity exerted different effects on foraminifera from different orders. Specifically, the proportion of species from Order Miliolida significantly increased whereas that of species from Order Rotaliida decreased with increasing salinity. High salinity-tolerant species Ammonia aomoriensis, Cribrononion gnythosuturatum, Ammonia tepida, and Quinqueloculina seminula could fill unoccupied ecological niches when the proportion of salinity-sensitive species has declined. Furthermore, our morphometric results showed that foraminiferal test size was significantly negatively correlated with salinity, and numerous abnormal specimens appeared in foraminiferal assemblages when salinity deviated from the field value. Our study revealed that intertidal foraminiferal assemblages had high adaptability at different salinities because of the existence of high salinity-tolerant dominant species. In addition, salinity variation can significantly alter foraminiferal morphology in test size and abnormality.","PeriodicalId":54832,"journal":{"name":"Journal of Foraminiferal Research","volume":"50 1","pages":"319-329"},"PeriodicalIF":1.1,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46516891","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Culver, Michael R Twarog, D. Mallinson, N. Shazili, J. Bidai
The distributions of modern foraminiferal species represent an important tool for petroleum geologists to characterize paleoenvironments. This paper documents the distribution of benthic foraminifera on the inner shelf (<40 m water depth) immediately offshore of the Terengganu River mouth, one of the three major drainages on the east coast of peninsular Malaysia. Sediment substrate type primarily controls the distribution of species; temperature, salinity, dissolved oxygen, and pH vary little in the study area and have little influence. Sandy substrates (mostly coarse and very coarse sand) from 20 to 40 m water depth are characterized by abundant specimens of the larger foraminifera Amphistegina spp. Muddy substrates immediately adjacent to the Terengganu River mouth from 12 to 20 m water depth are characterized by higher diversity assemblages dominated by several smaller calcareous taxa and the agglutinated species Ammobaculites exiguus. The latter species has been documented in muddy sediments at other river mouths on the east coast of peninsular Malaysia. Strong, seasonally reversing monsoon-driven currents affect sediment transport along the east coast of peninsular Malaysia and therefore indirectly influence the distributions of foraminiferal species. The results of this study add to the increasingly extensive database on modern foraminiferal distributions that provides a model for paleoenvironmental interpretations of hydrocarbon-bearing Neogene strata off the east coast of Thailand and peninsular Malaysia.
{"title":"Distribution of Foraminifera off the Terengganu River Mouth, East Coast Peninsular Malaysia","authors":"S. Culver, Michael R Twarog, D. Mallinson, N. Shazili, J. Bidai","doi":"10.2113/gsjfr.50.4.330","DOIUrl":"https://doi.org/10.2113/gsjfr.50.4.330","url":null,"abstract":"\u0000 The distributions of modern foraminiferal species represent an important tool for petroleum geologists to characterize paleoenvironments. This paper documents the distribution of benthic foraminifera on the inner shelf (<40 m water depth) immediately offshore of the Terengganu River mouth, one of the three major drainages on the east coast of peninsular Malaysia. Sediment substrate type primarily controls the distribution of species; temperature, salinity, dissolved oxygen, and pH vary little in the study area and have little influence. Sandy substrates (mostly coarse and very coarse sand) from 20 to 40 m water depth are characterized by abundant specimens of the larger foraminifera Amphistegina spp. Muddy substrates immediately adjacent to the Terengganu River mouth from 12 to 20 m water depth are characterized by higher diversity assemblages dominated by several smaller calcareous taxa and the agglutinated species Ammobaculites exiguus. The latter species has been documented in muddy sediments at other river mouths on the east coast of peninsular Malaysia. Strong, seasonally reversing monsoon-driven currents affect sediment transport along the east coast of peninsular Malaysia and therefore indirectly influence the distributions of foraminiferal species. The results of this study add to the increasingly extensive database on modern foraminiferal distributions that provides a model for paleoenvironmental interpretations of hydrocarbon-bearing Neogene strata off the east coast of Thailand and peninsular Malaysia.","PeriodicalId":54832,"journal":{"name":"Journal of Foraminiferal Research","volume":"50 1","pages":"330-341"},"PeriodicalIF":1.1,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42111253","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
From the upper Pliensbachian–Toarcian interval of the Neotethys, this is the first record of isolated foraminiferal assemblages obtained from the Ammonitico Rosso limestone successions. The studied sections of Bakonycsernye (Hungary) had been dated by ammonites. The foraminiferal fauna extracted by glacial acetic acid yielded 86 benthic foraminiferal taxa. Most specimens belonged to the suborders Spirillinina and Lagenina followed by the Ammodiscina. The representatives of suborders Astrorhizina, Komokioidea, Verneuilinina, Robertinina, and Rotaliina were subordinated; miliolids were absent. Paralingulina csernyensis n. sp. was described from the upper Pliensbachian. The majority of species have wide stratigraphic ranges, however the previously known distributions of seven species changed based on their appearances in these sections. Nevertheless, the stratigraphic distributions of the foraminiferal species enabled accurate dating to stage-level. Based on the comparison of the taxonomic composition with other coeval foraminiferal faunas of the Neotethys, foraminiferal biozones and bioevents are discussed in this paper.
从新特提斯的上pliensbachia - toarcian区间，这是第一次从菊石Rosso石灰岩序列中获得孤立的有孔虫组合记录。用菊石测定了Bakonycsernye(匈牙利)的年代。冰醋酸提取的有孔虫区系共得到86个底栖有孔虫类群。大多数标本属于螺旋藻亚目和Lagenina亚目，其次是ammodiscia。隶属于astrohizina亚目、Komokioidea亚目、Verneuilinina亚目、Robertinina亚目和Rotaliina亚目;毫液滴没有出现。副舌藻(paringulina csernyensis n. sp.)是由上pliensbach目发现的。大多数种具有较宽的地层范围，但已有7种的分布根据其在这些剖面中的出现而发生了变化。然而，有孔虫物种的地层分布使其能够精确地定年至阶段水平。本文在比较新特提斯虫与其他同时期有孔虫动物群的分类组成的基础上，讨论了有孔虫生物带和生物事件。
{"title":"Foraminiferal Faunal Changes in the Upper Pliensbachian–Toarcian Ammonitico Rosso Sections (Bakonycsernye, Hungary)","authors":"Á. Görög, Gábor Zsiborás","doi":"10.2113/gsjfr.50.4.342","DOIUrl":"https://doi.org/10.2113/gsjfr.50.4.342","url":null,"abstract":"\u0000 From the upper Pliensbachian–Toarcian interval of the Neotethys, this is the first record of isolated foraminiferal assemblages obtained from the Ammonitico Rosso limestone successions. The studied sections of Bakonycsernye (Hungary) had been dated by ammonites. The foraminiferal fauna extracted by glacial acetic acid yielded 86 benthic foraminiferal taxa. Most specimens belonged to the suborders Spirillinina and Lagenina followed by the Ammodiscina. The representatives of suborders Astrorhizina, Komokioidea, Verneuilinina, Robertinina, and Rotaliina were subordinated; miliolids were absent. Paralingulina csernyensis n. sp. was described from the upper Pliensbachian. The majority of species have wide stratigraphic ranges, however the previously known distributions of seven species changed based on their appearances in these sections. Nevertheless, the stratigraphic distributions of the foraminiferal species enabled accurate dating to stage-level. Based on the comparison of the taxonomic composition with other coeval foraminiferal faunas of the Neotethys, foraminiferal biozones and bioevents are discussed in this paper.","PeriodicalId":54832,"journal":{"name":"Journal of Foraminiferal Research","volume":"50 1","pages":"342-372"},"PeriodicalIF":1.1,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43764898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The content and scope of the Cushman Laboratory and Cushman Foundation Special Publications are briefly described and summarized in four tables. Seventy-seven Special Publications have been produced over the past 90+ years. Most are taxonomic works, of variable length (up to 661 pages) with copious illustrations (up to 389 plates) in the form of images of foraminiferal taxa (six Special Publications are on radiolaria and one on thecamoebians). The Special Publications underpin all other aspects of micropaleontological (particularly foraminiferal) research ranging from biostratigraphy to paleoceanography to evolutionary studies.
{"title":"Cushman Special Publications: History and Scope","authors":"S. Culver, Pamela Buzas-Stephens","doi":"10.2113/gsjfr.50.4.403","DOIUrl":"https://doi.org/10.2113/gsjfr.50.4.403","url":null,"abstract":"The content and scope of the Cushman Laboratory and Cushman Foundation Special Publications are briefly described and summarized in four tables. Seventy-seven Special Publications have been produced over the past 90+ years. Most are taxonomic works, of variable length (up to 661 pages) with copious illustrations (up to 389 plates) in the form of images of foraminiferal taxa (six Special Publications are on radiolaria and one on thecamoebians). The Special Publications underpin all other aspects of micropaleontological (particularly foraminiferal) research ranging from biostratigraphy to paleoceanography to evolutionary studies.","PeriodicalId":54832,"journal":{"name":"Journal of Foraminiferal Research","volume":"50 1","pages":"403-411"},"PeriodicalIF":1.1,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48988897","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Index To Volume 50, 2020","authors":"","doi":"10.2113/gsjfr.50.4.413","DOIUrl":"https://doi.org/10.2113/gsjfr.50.4.413","url":null,"abstract":"","PeriodicalId":54832,"journal":{"name":"Journal of Foraminiferal Research","volume":"1 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42957318","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Salt-marsh foraminifera are sea-level proxies used to quantitatively reconstruct Holocene paleo-marsh elevations (PME) and subsequently relative sea level (RSL). The reliability of these reconstructions is partly dependent upon counting enough foraminifera to accurately characterize assemblages, while counting fewer tests allows more samples to be processed. We test the influence of count size on PME reconstructions by repeatedly subsampling foraminiferal assemblages preserved in a core of salt-marsh peat (from Newfoundland, Canada) with unusually large counts (up to 1595). Application of a single, weighted-averaging transfer function developed from a regional-scale modern training set to these ecologically-plausible simulated assemblages generated PME reconstructions at count sizes of 10–700. Reconstructed PMEs stabilize at counts sizes greater than ∼50 and counts exceeding ∼250 tests show little return for the additional time invested. The absence of some rare taxa in low counts is unlikely to markedly influence results from weighted-averaging transfer functions. Subsampling of modern foraminifera indicates that cross-validated transfer function performance shows only modest improvement when more than ∼40 foraminifera are counted. Studies seeking to understand multi-meter and millennial scale RSL trends should count more than ∼50 tests. The precision sought by studies aiming to resolve decimeter- and decadal-scale RSL variability is best achieved with counts greater than ∼75. In most studies seeking to reconstruct PME, effort is more productively allocated by counting relatively fewer foraminifera in more core samples than in counting large numbers of individuals. Target count sizes of 100–300 in existing studies are likely conservative and robust. Given the low diversity of salt-marsh foraminiferal assemblages, our results are likely applicable throughout and beyond northeastern North America.
{"title":"Enough is Enough, or More is More? Testing the Influence of Foraminiferal Count Size on Reconstructions of Paleo-Marsh Elevation","authors":"A. Kemp, A. Wright, N. Cahill","doi":"10.2113/gsjfr.50.3.266","DOIUrl":"https://doi.org/10.2113/gsjfr.50.3.266","url":null,"abstract":"\u0000 Salt-marsh foraminifera are sea-level proxies used to quantitatively reconstruct Holocene paleo-marsh elevations (PME) and subsequently relative sea level (RSL). The reliability of these reconstructions is partly dependent upon counting enough foraminifera to accurately characterize assemblages, while counting fewer tests allows more samples to be processed. We test the influence of count size on PME reconstructions by repeatedly subsampling foraminiferal assemblages preserved in a core of salt-marsh peat (from Newfoundland, Canada) with unusually large counts (up to 1595). Application of a single, weighted-averaging transfer function developed from a regional-scale modern training set to these ecologically-plausible simulated assemblages generated PME reconstructions at count sizes of 10–700. Reconstructed PMEs stabilize at counts sizes greater than ∼50 and counts exceeding ∼250 tests show little return for the additional time invested. The absence of some rare taxa in low counts is unlikely to markedly influence results from weighted-averaging transfer functions. Subsampling of modern foraminifera indicates that cross-validated transfer function performance shows only modest improvement when more than ∼40 foraminifera are counted. Studies seeking to understand multi-meter and millennial scale RSL trends should count more than ∼50 tests. The precision sought by studies aiming to resolve decimeter- and decadal-scale RSL variability is best achieved with counts greater than ∼75. In most studies seeking to reconstruct PME, effort is more productively allocated by counting relatively fewer foraminifera in more core samples than in counting large numbers of individuals. Target count sizes of 100–300 in existing studies are likely conservative and robust. Given the low diversity of salt-marsh foraminiferal assemblages, our results are likely applicable throughout and beyond northeastern North America.","PeriodicalId":54832,"journal":{"name":"Journal of Foraminiferal Research","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2113/gsjfr.50.3.266","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46909737","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The ecological balance of nature is defined as an equilibrium between species richness (S) and species evenness (E) such that diversity (H) remains constant with time. Based on this definition, our approach identifies growth or decline in communities as perturbations from stasis and has successfully done so for benthic foraminiferal communities. Here, we examine whether this approach is appropriate for planktonic foraminifera. To do so, we utilized planktonic foraminiferal counts (39 samples, 66% recovery) from Maastrichtian sediments in the Weddell Sea from ODP Hole 690C. A total of 24 species were observed and both >63-µm and >150-µm fractions were counted. In the >63-µm fraction, nine communities were recognized while in the >150-µm fraction, there were 12. In both fractions at 70.45 Ma, a boundary was recognized and immediately after this boundary, a community in growth was identified. A trend of increasing diversity upcore was substantiated by regression on individual samples. For our purposes, the >150-µm fraction in this data set is sufficient to recognize community trends. The >150-µm fraction in Hole 690C has 82% of the sampling time in stasis and an average time per community is 0.85 Ma. The >63-µm fraction has 73% of the sampling time in stasis and an average time per community of 1.02 Ma.
{"title":"The Ecological Balance of Nature: Identifying Stasis and Growth in Late Cretaceous Planktonic Foraminifera from ODP Hole 690C (Weddell Sea)","authors":"M. Buzas, L. Hayek, B. Huber","doi":"10.2113/gsjfr.50.3.313","DOIUrl":"https://doi.org/10.2113/gsjfr.50.3.313","url":null,"abstract":"\u0000 The ecological balance of nature is defined as an equilibrium between species richness (S) and species evenness (E) such that diversity (H) remains constant with time. Based on this definition, our approach identifies growth or decline in communities as perturbations from stasis and has successfully done so for benthic foraminiferal communities. Here, we examine whether this approach is appropriate for planktonic foraminifera. To do so, we utilized planktonic foraminiferal counts (39 samples, 66% recovery) from Maastrichtian sediments in the Weddell Sea from ODP Hole 690C. A total of 24 species were observed and both >63-µm and >150-µm fractions were counted. In the >63-µm fraction, nine communities were recognized while in the >150-µm fraction, there were 12. In both fractions at 70.45 Ma, a boundary was recognized and immediately after this boundary, a community in growth was identified. A trend of increasing diversity upcore was substantiated by regression on individual samples. For our purposes, the >150-µm fraction in this data set is sufficient to recognize community trends. The >150-µm fraction in Hole 690C has 82% of the sampling time in stasis and an average time per community is 0.85 Ma. The >63-µm fraction has 73% of the sampling time in stasis and an average time per community of 1.02 Ma.","PeriodicalId":54832,"journal":{"name":"Journal of Foraminiferal Research","volume":"50 1","pages":"313-317"},"PeriodicalIF":1.1,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2113/gsjfr.50.3.313","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42046995","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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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