scholarly journals New insights into the taxonomy and evolution of Jurassic planktonic foraminifera

2021 ◽  
Vol 140 (1) ◽  
Author(s):  
Felix Gradstein ◽  
Anna Waskowska
Keyword(s):  
Late Jurassic ◽  
Planktonic Foraminifera ◽  
Cost Effective ◽  
Evolutionary Transition ◽  
Communication Tools ◽  
Thin Sections ◽  
Led Lighting ◽  
Foraminiferal Species ◽  
Upper Bajocian ◽  
Ontogenic Development

AbstractGlobuligerina glinskikhae nov. sp. Gradstein & Waskowska and Globuligerina waskowskae nov. sp. Gradstein are new species of Jurassic planktonic foraminifera from the Middle Jurassic of Dagestan and Poland. G. glinskikhae nov. sp. with its remarkable ‘protoglobigerine’ test may be an early evolutionary offshoot of Globuligerina oxfordiana (Grigelis). It may be an index taxon for upper Bajocian through Bathonian strata in Eastern Europe and Southwest Asia, and might be recognizable also in thin sections. We consider G. waskowskae nov. sp. to be a possible forerunner of Conoglobigerina helvetojurassica (Haeusler), the first planktonic foraminiferal species with a reticulate wall texture. Currently, is only known from Poland. In some localities, specimens of G. oxfordiana and of G. glinskikhae nov. sp. posses an additional apertural opening, often lacking a rim; its function is enigmatic. The postulated lineage from Jurassic Globuligerina balakhmatovae (Morozova) to Cretaceous Clavihedbergella eocretacea Neagu is refined with the description of Petaloglobigerina simmonsi nov. gen., nov. sp. Gradstein from the Kimmeridgian of Portugal. The evolutionary transition from G. balakhmatovae to P. simmonsi occurs by means of the ontogenic development of a petaloid test, with a pronounced flattening of the whorl with ovate chambers, the last ones often offset and twisted. Jurassic planktonic foraminifera, now known to consist of three genera and 12+ species underwent long periods of stasis, interrupted by late Bajocian, mid-Oxfordian and early Kimmeridgian evolution. The three ‘stasis and root’ taxa G. oxfordiana, G. bathoniana and G. balakhmatovae are geographically widespread in lower to mid palaeo-latitudes, and stratigraphically long ranging within the Middle and Late Jurassic. Modern digital microscopes, with co-axial and side LED lighting and excellent image stacking software are important tools in the study of Jurassic planktonic foraminifera, and fast and cost-effective communication tools in modern micropalaeontology.

scholarly journals Lithostratigraphy and microfacies analysis of Avanah Formation (Middle Eocene) in Gomaspan section northeast Erbil City, Kurdistan region, Iraq

2021 ◽  
Author(s):  
Irfan Sh. Asaad ◽  
Keyword(s):  
Middle Eocene ◽  
Planktonic Foraminifera ◽  
Middle Part ◽  
Petrographic Analysis ◽  
Microfacies Analysis ◽  
Dolomitic Limestone ◽  
Kurdistan Region ◽  
Thin Sections ◽  
Lithostratigraphic Units ◽  
Lagoon Environment

Lithostratigraphy and microfacies analysis of the Avanah Formation (Middle Eocene) were studied in the Gomaspan section in the Bina Bawi anticline, northeast of Erbil city, Kurdistan Region, Iraq. The field observations refer that the formation attains 56 m of medium to thick bedded yellow limestone, grey dolomitic limestone and blue marly dolomitic limestone interbedded with thin beds of blue marl and dark grey shale with an interval of sandy limestone in the middle part and thin to medium bedded limestone interbedded with red mudstone. The petrographic study of 29 thin sections of Avanah carbonates revealed that the majority of the matrix is carbonate mud (micrite) with few microspar. The skeletal grains include benthic foraminifera, dasycladacean green algae, ostracods, calcispheres, pelecypods, rare planktonic foraminifera and bryozoa in addition to bioclasts. Non-skeletal grains encompass peloids, oncoids, intraclasts and extraclasts with common monocrystalline quartz. Based on the field observation and petrographic analysis, three different lithostratigraphic units were identified. They are in ascending order: A-Thick bedded dolomitic marly limestone interbedded with shale. B- Bedded dolomitic limestone interbedded with shale and marl. C- Thin to medium bedded limestone interbedded with red mudstone. Depending on detailed microfacies analysis of carbonate rocks, three main microfacies and 12 submicrofacies are recognized. From the sum of all petrographic, facies, textural analyses, it is concluded that Avanah Formation in Gomaspan section, was deposited in shallow marine environment, semi restricted lagoon, in lower and upper parts and open lagoon environment in the middle part interval.

Dimmable and Cost-Effective DC Driving Technique for Flicker Mitigation in LED Lighting

2014 ◽  
Vol 10 (9) ◽  
pp. 766-774 ◽  
Author(s):  
Qian Wang ◽  
Tao Li ◽  
Qian-Hua He
Keyword(s):  
Cost Effective ◽  
Led Lighting

scholarly journals The Interdependency of the Morphological Variations of the Planktonic Foraminiferal Species Globigerina bulloides in Surface Sediments on the Environmental Parameters of the Southwestern Indian Ocean

2014 ◽  
Vol 2014 ◽  
pp. 1-9
Author(s):  
Abhijit Mazumder ◽  
Neloy Khare ◽  
Pawan Govil
Keyword(s):  
Indian Ocean ◽  
Surface Temperature ◽  
Sea Surface Temperature ◽  
Census Data ◽  
Planktonic Foraminifera ◽  
Morphological Characteristics ◽  
Sea Surface ◽  
Globigerina Bulloides ◽  
Foraminiferal Species ◽  
Ecological Parameters

18 surface sediment samples collected from a north-south transect along the Indian Ocean have been analyzed for planktonic Foraminifera content. Among the other planktonic foraminiferal faunas, Globigerina bulloides was present substantially in all samples. Census data of G. bulloides were measured for different parameters (average size, mean proloculus size, coiling direction, and number of chambers) and a Q-mode cluster analysis was applied on these data. Samples were segregated into two homogeneous clusters, each reflecting particular environmental conditions. Two clusters are as follows: (1) Cluster A, comprised of 6 samples and characterized by the highest range of foraminiferal and ecological parameters, except sea surface temperature and salinity which shows the lowest range, and (2) Cluster B, comprised of 12 samples and characterized by the lowest range of foraminiferal parameters and ecological parameters, except sea surface temperature and salinity which shows the highest range. The study suggests that the ecological parameters are the governing factors for the morphological characteristics of planktonic foraminiferal species G. bulloides.

scholarly journals The new foraminiferal genus <i>Ammogloborotaloides</i> n. gen. and subfamily Ammogloborotaloidinae n. subfam. from the Neogene of Venezuela: an example of isomorphism between agglutinated and planktonic Foraminifera

2011 ◽  
Vol 30 (1) ◽  
pp. 11-16
Author(s):  
Michael A. Kaminski ◽  
Jime Contreras
Keyword(s):  
New Species ◽  
Type Species ◽  
Planktonic Foraminifera ◽  
Petroleum Industry ◽  
Foraminiferal Species ◽  
Two New Species ◽  
Globorotalia Truncatulinoides

Abstract. We report the occurrence of two new species of the new agglutinated foraminiferal genus Ammogloborotaloides in the Miocene of western Venezuela. These two taxa have been assigned informal names and have been known to the petroleum industry in Venezuela for many years, but have never been described. A. truncatulinoidiformis n. sp. is the type species and the second species, A. sp. 16, is left in open nomenclature. The two species of Ammogloborotaloides are strongly isomorphic with the planktonic foraminiferal species Globorotalia truncatulinoides and Globorotalia crassaformis, and illustrate the possible evolutionary connections between agglutinated benthics and the planktonic foraminifera.

scholarly journals Palaeogene triserial planktonic foraminifera

1998 ◽  
Vol 17 (1) ◽  
pp. 61-70 ◽  
Author(s):  
D. Graham Jenkins ◽  
John E. Whittaker ◽  
Dennis Curry
Keyword(s):  
Type Species ◽  
Planktonic Foraminifera ◽  
Junior Synonym ◽  
Test Surface ◽  
Early Eocene ◽  
Late Oligocene ◽  
Foraminiferal Species

Abstract. Triserial planktonic foraminiferal species from the Palaeogene are classified into the Early Danian Guembelitria, with pore mounds on the test surface, and the Early Eocene-Late Oligocene Jenkinsina, which are also microperforate but lack pore mounds. The stratigraphic and palaeogeographic ranges are discussed, the holotype of G. cretacea Cushman (the type species of Guembelitria) is re-illustrated, and neotypes designated for G. danica (Hofker) and Jenkinsina triseriata (Terquem). Chiloguembelitria is shown to be a junior synonym of Guembelitria.

Ontogeny of gastric inhibitory peptide in the human gastro-intestinal tract and endocrine pancreas

1982 ◽  
Vol 99 (1) ◽  
pp. 112-121 ◽  
Author(s):  
P. Leduque ◽  
C. Gespach ◽  
J. C. Brown ◽  
G. Rosselin ◽  
P. M. Dubois
Keyword(s):  
Endocrine Pancreas ◽  
Tissue Concentration ◽  
Endocrine Regulation ◽  
Inhibitory Peptide ◽  
Thin Sections ◽  
Gastric Inhibitory Peptide ◽  
Regulation Of Metabolism ◽  
Ontogenic Development ◽  
Wet Weight ◽  
Gastro Intestinal Tract

Abstract. The appearance and distribution of the gastro-intestinal hormone, gastric inhibitory peptide (GIP) were examined in the gastro-entero-pancreatic system of human foetuses, aged 5–24 weeks, by immunocytochemistry or radioimmunoassay. The first immunoreactive cells were observed in the gut from 16 weeks of gestation. The GIP-containing cells were localized preferentially in the villous epithelium of the small intestine. In the radioimmunoassay, the highest concentrations of immunoreactive GIP (IR-GIP) were detected from 13 to 21 weeks of gestation. The tissue concentration of IR-GIP was 68.10 ± 10.70 ng/g wet weight of duodenum, 30.29 ± 3.96 ng/g wet weight of jejuno-ileum and 3.05 ± 1.97 ng/g wet weight in the colon. Measurable amounts of IR-GIP (4.93 ± 1.57 ng/g wet weight of organ) were found from 9 to 12 weeks in the jejuno-ileal region. The ontogenic development of IR-GIP was studied in this region. From 13 to 21 weeks of gestation, the IR-GIP content per g of organ increased about 6-fold. In the endocrine pancreas, GIP antiserum No. R07 was potent in staining A cells from 14 weeks of gestation. In radioimmunological tests, no cross-reactions of the anti-GIP sera R 07 and GP 01 with heterologous peptides were observed. Labelling of paraffin and semi-thin sections was subjected not only to the usual specificity tests, but also to particularly extensive cross-reaction studies. GIP-like immunoreactivity was not inhibited by absorptions against heterologous peptides added at varying concentrations. The immunocytological and radioimmunological results are consistent with an eventual implication of GIP in the endocrine regulation of metabolism or in the development of the gastro-entero-pancreatic system during the intrauterine life in man.

scholarly journals Planktonic foraminifera from the Pliocene Coralline Crag of Suffolk, Eastern England

1988 ◽  
Vol 7 (1) ◽  
pp. 1-10 ◽  
Author(s):  
D. G. Jenkins ◽  
D. Curry ◽  
B. M. Funnell ◽  
J. E. Whittaker
Keyword(s):  
North Atlantic ◽  
Planktonic Foraminifera ◽  
Bivalve Molluscs ◽  
Important Species ◽  
The North ◽  
Foraminiferal Species ◽  
Published Evidence ◽  
The North Sea ◽  
The North Atlantic ◽  
Water Species

Abstract. Nine species of planktonic foraminifera have recently been identified from the Coralline Crag of Suffolk, Eastern England. Stratigraphically important species include Globorotalia puncticulata (Deshayes) and Neogloboquadrina atlantica (Berggren) whose joint ranges, based on evidence from the North Atlantic, indicate an age for the deposit of between c. 4.2 and 2.3 Ma; other published evidence suggests that it may not be younger than c. 3.4 Ma. The low planktonic foraminiferal species diversity is interpreted as being due to a combination of factors, including the shallow water nature of the Coralline Crag, which would preclude deeper water species of planktonic foraminifera, and the possibility that the source of the fauna was from relatively high latitudes of the North Atlantic via the northern entrance to the North Sea. The planktonic foraminifera recorded indicate that the water temperature of the sea was within the range 10–18°C.The Coralline Crag contains very rich Lusitanian faunas of gastropod and bivalve molluscs, bryozoans, ostracods and benthic foraminifera.

scholarly journals Assessing the Accuracy of Fossil Datum Levels: <i>Globorotalia margaritae</i> Foraminiferida, a Pliocene Test Case

1991 ◽  
Vol 9 (2) ◽  
pp. 225-231 ◽  
Author(s):  
P. P. E. Weaver ◽  
H. Bergsten
Keyword(s):  
Planktonic Foraminifera ◽  
Geographical Range ◽  
Test Case ◽  
Simple Explanation ◽  
Piston Core ◽  
Global Arrays ◽  
Foraminiferal Species ◽  
Stratigraphic Ranges

Abstract. The stratigraphic distribution of the planktonic foraminiferal species Globorotalia margaritae has been determined in 34 DSDP, ODP and piston core sites from throughout the world’s oceans and from one land section. All these sites have good palaeomagnetic records, and thus the age of the first and last appearance of G. margaritae can be determined in each case. The results show strong diachronism and indicate that this is not a good species to use for correlation. There appears to be no simple explanation for this diachronism, dissolution is probably a contributing factor in the deeper sites, and the edges of the geographical range of the species show shorter stratigraphic ranges but these factors do not explain all the data. We suggest that diachronism in planktonic foraminifera may be common, but without global arrays of palaeomagnetically dated cores it will be very difficult to distinguish reliable species from unreliable ones.

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