late ypresian
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2021 ◽  
Author(s):  
Seraina Klopfstein

With an estimated 100,000 extant species, Darwin wasps (Ichneumonidae) are more specious than all vertebrates together. However, only 288 fossil species have been described to date, with hundreds more awaiting formal description in palaeontological collections. One of the largest gaps in our knowledge concerns the ~12 million years between the K-PG mass extinction and the late Ypresian, from which only two species have been formally described, including Pimpla stigmatica Henriksen from the Danish Fur Formation (~55 Ma). Ie here redescribe and reclassify this species in the genus Epitheronia Gupta, n. comb., and describe nine new species from this fossil locality that are consistent with a placement in Pimplinae: Crusopimpla collina n. sp., C. elongata n. sp., C. minuta n. sp., C. rettigi n. sp., C. violina n. sp., Theronia? furensis n. sp., T. nigriscutum n. sp., Xanthopimpla ciboisae n. sp., and X. crescendae n. sp. The diagnosis of the genus Crusopimpla Kopylov, Spasojevic & Klopfstein is amend in the light of the new species. By comparing the preserved colouration between and within specimens of different species, we draw conclusions about the taxonomic usefulness of colour patterns observed in Fur Formation ichneumonids. The number of described species of pimpline parasitoid wasps from Fur is very high when compared to any other fossil deposit, but low with respect to numbers of extant species. Further study and excavation of Fur ichneumonids will certainly reveal an even higher diversity.


2021 ◽  
Vol 19 ◽  
pp. 1-XX
Author(s):  
Roi Silva-Casal ◽  
Josep Serra-Kiel ◽  
Adriana Rodriguez-Pintó ◽  
Emilio L Pueyo ◽  
Marcos Aurell ◽  
...  

An extense systematic description of the Eocene larger foraminiferal faunas recorded in the South Pyrenean Basin (Sierras Exteriores) is presented herein. The large dataset provided in this work includes both Nummulites and Alveolina species, along with a variety of other porcellaneous and hyaline taxa with lesser biostratigraphic relevance, are represented. The larger foraminifera described in this work correspond mainly to the Lutetian (SBZ13 to SBZ16 biozones) interval, but late Ypresian (SBZ11, Cuisian) and Bartonian (SBZ17) shallow benthic zones have also been identified.As one of the most relevant results of this systematic analysis, a new species, Idalina osquetaensis, is described. The systematic revision of middle to late Lutetian alveolines led to a reassessment of A. fusiformis and the finding of two new precursor forms, described as affinis of their corresponding species, A. aff. fragilis and A. aff. elongata. The new forms A. aff. elongata and A. aff. fragilis fill the gap in the middle to late Lutetian alveolinid biostratigraphy. Despite not being exclusive to SBZ16, these new forms provide realiable biostratigraphic information where Nummulites are not present. This realibility lies on the correlation of Nummulites and Alveolina biomarkers in the same sections and their calibration to the global time scale through magnetostratigraphy. In fact, magnetostratigraphic calibration of all described taxa is also provided, along with an update of the SBZ calibration to the current Geologic Time Scale (Gradstein et al., 2012).


2021 ◽  
Author(s):  
Yavuz Özdemir ◽  
Çağrı Mercan ◽  
Vural Oyan ◽  
Ayşe Atakul-Özdemir ◽  
Nilgün Güleç ◽  
...  

<p>Maden Complex exposed in Eastern Turkey, is a succession of volcano-sedimentary rocks and tectonically overlain by Bitlis Metamorphics and Cretaceous ophiolitic rocks. The succession includes shallow-water deposits and deep marine pelagic sediments intercalated with pillow lavas ranging from a few centimeters to ten meters in diameter. The planktonic foraminiferal assemblages from micritic limestones and zircon U-Pb ages from selected sedimentary rocks indicate the age of Late Ypresian - Early Lutetian. Plagioclase and  clinopyroxenes are the main mineral phases, olivine rarely found as altered phenocrysts. Clinopyroxenes are augite and diopside, and their compositions are ranging between Wo<sub>44-51</sub>, En<sub>27-43</sub>, Fe<sub>10-21</sub>. The anorthite contents of plagioclases are between 32- 67 % in unaltered grains. The crystallization temperatures and pressures obtained from clinopyroxene chemistry are ranging from 1126 to 1250<sup>o</sup>C and 3 to 8 Kbar, respectively. The majority of the volcanic/subvolcanic rocks are subalkaline-tholeiitic basalts however; a few andesitic and rhyolitic derivatives are also present. The whole – rock and  Sr-Nd-Pb isotope compositions reveal that the  basaltic rocks are originated from E-MORB like asthenospheric mantle source without a subduction component.</p>


Geodiversitas ◽  
2020 ◽  
Vol 42 (13) ◽  
pp. 185 ◽  
Author(s):  
Floréal Solé ◽  
Bernard Marandat ◽  
Fabrice Lihoreau
Keyword(s):  

Author(s):  
Jun A. Ebersole ◽  
David J. Cicimurri ◽  
Gary L. Stringer

The Tallahatta Formation, Lisbon Formation, and Gosport Sand are the three lithostratigraphic units that make up the lower-to-middle Eocene Claiborne Group. In Alabama, these marine units are among the most fossiliferous in the state and a long history of scattered reports have attempted to document their fossil diversity. In this study, we examined 20931 elasmobranch and bony fish elements, including otoliths, derived from Claiborne Group units in Alabama and identified 115 unequivocal taxa. Among the taxa identified, one new species is described, Carcharhinus mancinae sp. nov., and Pseudabdounia gen. nov. is a new genus erected to include two species formerly placed within Abdounia Capatta, 1980. New taxonomic combinations proposed include Pseudabdounia claibornensis (White, 1956) gen. et comb. nov., Pseudabdounia recticona (Winkler, 1874) gen. et comb. nov., Physogaleus alabamensis (Leriche, 1942) comb. nov., and Eutrichiurides plicidens (Arambourg, 1952) comb. nov. We also report the first North American paleobiogeographic occurrences of Aturobatis aff. A. aquensis Adnet, 2006, Brachycarcharias atlasi (Arambourg, 1952), Eutrichiurides plicidens comb. nov., Galeorhinus louisi Adnet & Cappetta, 2008, Ginglymostoma maroccanum Noubhani & Cappetta, 1997, Gymnosarda sp., Mennerotodus sp., Rhizoprionodon ganntourensis (Arambourg, 1952), Stenoscyllium aff. S. priemi Noubhani & Cappetta, 1997, Trichiurus oshosunensis White, 1926, and the first North American occurrence for a fossil member of the Balistidae Risso, 1810. Our sample also included 26 taxa that represented first paleobiogeographic occurrences for Alabama, including Abdounia beaugei (Arambourg, 1935), Albula eppsi White, 1931, Ariosoma nonsector Nolf & Stringer, 2003, Anisotremus? sp., Anomotodon sp., Brachycarcharias twiggsensis (Case, 1981), Burnhamia daviesi (Woodward, 1889), Eoplinthicus yazooensis Capetta & Stringer, 2002, Galeorhinus ypresiensis (Casier, 1946), Gnathophis meridies (Frizzell & Lamber, 1962), Haemulon? obliquus (Müller, 1999), Hypolophodon sylvestris (White, 1931), Malacanthus? sulcatus (Koken, 1888), Meridiania cf. M. convexa Case, 1994, Palaeocybium proosti (Storms, 1897), Paraconger sector (Koken, 1888), Paralbula aff. P. marylandica Blake, 1940, Phyllodus toliapicus Agassiz, 1844, Propristis schweinfurthi Dames, 1883, Pycnodus sp., Pythonichthys colei (Müller, 1999), Scomberomorus stormsi (Leriche, 1905), Signata stenzeli Frizzell & Dante, 1965, and Signata nicoli Frizzell & Dante, 1965, and the first Paleogene occurrences in Alabama of a member of the Gobiidae Cuvier, 1816. A biostratigraphic analysis of our sample showed stratigraphic range extensions for several taxa, including the first Bartonian occurrences of Eoplinthicus yazooensis, Jacquhermania duponti (Winkler, 1876), Meridiania cf. M. convexa, Phyllodus toliapicus, and “Rhinobatos” bruxelliensis (Jaekel, 1894), range extensions into the late Ypresian and Bartonian for Tethylamna dunni Cappetta & Case, 2016 and Scoliodon conecuhensis Cappetta & Case, 2016, the first late Ypresian records of Galeorhinus louisi, the first Lutetian occurrence of Gymnosarda Gill, 1862, and a range extension for Fisherichthys aff. F. folmeri Weems, 1999 into the middle Bartonian. Larger biostratigraphic and evolutionary trends are also documented, such as the acquisition of serrations in Otodus spp., possible population increases for the Rhinopterinae Jordan & Evermann, 1896 and Carcharhiniformes Compagno, 1973 in the Bartonian, and the apparent diversification of the Tetraodontiformes Berg, 1940 during the same stage. This study helps better our understanding of early-to-middle Eocene elasmobranch and bony fish diversity, paleobiogeography, and biostratigraphy in the Gulf Coastal Plain of North America.


2019 ◽  
Vol 27 (3) ◽  
pp. 93-122
Author(s):  
G. N. Aleksandrova

As a result of studying the stratigraphic distribution of palynomorphs in the Cenozoic marine strata of the Kvachina Bay section, six different age associations of dinocysts, spores, and pollen have been identified. Their analysis made it possible to date the deposits of the Tigil Unit by the Bartonian–Pribonian, the Belesovataya Unit – by the Oligocene–Early Miocene, and the overlying lower part of the Kavranian Series – by the Early Miocene. The age of the dislocated rocks underlying the Tigil Unit is estimated as Late Ypresian–(?) Early Lutetian. On the basis of the revealed changes in the ratios of the ecological groups of palynomorphs, conclusions were made about the paleoenvironmental in which the formation of strata took place in various time intervals.


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