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1.
An incomplete skull of the leptonectid ichthyosaur Eurhinosaurus longirostris found in the Rietheim Member (previously “Posidonienschiefer”; Toarcian, Early Jurassic) of Staffelegg, Canton Aargau, is
the first record from Switzerland of this taxon and supports the status of Eurhinosaurus longirostris as a palaeobiogeographic very widespread ichthyosaur species in the Early Toarcian of Western Europe. Being from either the
Bifrons or Variabilis zone, it is one of the youngest records of Eurhinosaurus and one of the few diagnostic ichthyosaur finds from this time interval. The partial skull is well articulated and preserved
three-dimensionally in a carbonate concretion. Both the mode of preservation of the ichthyosaur and an associated ammonoid
(Catacoeloceras raquinianum) provided the age of the concretion, which had been collected from scree. Taphocoenosis and taphonomy show the C. raquinianum to be one of few non re-worked fossils recorded from the Early to Late Toarcian boundary (Bifrons/Variabilis zone) of northern
Switzerland in general and of this ammonite species in particular. The Toarcian section at Staffelegg differs from other localities
where strata of the same age are exposed with respect to facies variations of the Rietheim Member (previously “Posidonienschiefer”,
Early Toarcian) and the extraordinarily high thickness of the Gross Wolf Member (previously “Jurensis-Mergel”, Late Toarcian). 相似文献
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John P. Green Dean R. Lomax 《Proceedings of the Geologists' Association. Geologists' Association》2014
A fragmentary ichthyosaur specimen collected in situ at Castle Top Quarry in Nettleton, Lincolnshire, UK from exposures of the Lower Cretaceous (Berriasian) Spilsby Sandstone Formation (Subcraspedites ?preplicomphalus Zone) is reported. In general, Early Cretaceous ichthyosaurs from the Berriasian to Barremian are poorly understood. Despite the fragmentary nature of the described specimen, it is the first ichthyosaur reported from this specific zone and adds to the literature another rare ichthyosaur from the Berriasian. 相似文献
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A new species of wasp from the Laiyang Formation in Shandong, China is described and named Cretaproscolia asiatica sp. nov. It is the second record of the genus Cretaproscolia Rasnitsyn and Martínez-Delclòs, 1999, and extends the distribution of the genus from the Lower Cretaceous of South America into the upper Mesozoic of East Asia. The diagnosis of Cretaproscolia is emended based on the new material. 相似文献
7.
Alan D. WanamakerJr. Karl J. Kreutz Bernd R. Schöne Kirk A. Maasch Andrew J. Pershing Harold W. Borns Douglas S. Introne Scott Feindel 《International Journal of Earth Sciences》2009,98(1):19-29
To investigate environmental variability during the late Holocene in the western Gulf of Maine, USA, we collected a 142-year-old
living bivalve (Arctica islandica) in 2004, and three fossil A. islandica shells of the Medieval Warm Period (MWP) and late MWP / Little Ice Age (LIA) period (corrected 14CAMS = 1030 ± 78 ad; 1320 ± 45 ad; 1357 ± 40 ad) in 1996. We compared the growth record of the modern shell with continuous plankton recorder (CPR) time-series (1961–2003)
from the Gulf of Maine. A significant correlation (r
2 = 0.55; p < 0.0001) exists between the standardized annual growth index (SGI) of the modern shell and the relative abundance of zooplankton
species Calanus finmarchicus. We therefore propose that SGI data from A. islandica is a valid proxy for paleo-productivity of at least one major zooplankton taxa. SGIs from these shells reveal significant
periods of 2–6 years (NAO-like) based on wavelet analysis, multitaper method (MTM) analysis and singular spectrum analysis
(SSA) during the late Holocene. Based on established physical oceanographic observation in the Gulf of Maine, we suggest that
slope water variability coupled with North Atlantic Oscillation (NAO) dynamics is primarily responsible for the observed SGI
variability.
Special Issue: AGU OS06 special issue “Ocean’s role in climate change—a paleo perspective”. 相似文献
8.
Novelaria, a new genus of rhagionid of late Albian age with three new species, is the first record of this family from Charentes amber (southwestern France). The new genus is probably closely related to the recent genus Chrysopilus. However its relationship with the other fossils in amber is discussed. A key for separation of the new species is provided and the diversity of the family during the Cretaceous is also briefly discussed. 相似文献
9.
Mirovia 《Cretaceous Research》2002,23(6):761
The Lower–Middle Albian coaly clay bed of the Escucha Formation, which is exposed at Rubielos de Mora (eastern Iberian Ranges, Spain), contains a diverse fossil plant assemblage. Among the taxa present in this layer, Mirovia gothanii Gomez sp. nov. differs from other species of the genus by its greater leaf length, margins typically overhanging the depressed stomatal groove, a single short, blunt, papilla borne by each subsidiary cell, non-stomatal cells inside the groove and margins, and a higher number of resin ducts in the mesophyll. Morphological study of the well-preserved cuticles demonstrates that the species also occurs in Lower Cretaceous coals of Santa Maria de Meià (Pyrenees, Spain) where Gothan (1954) described it as Sciadopitytes sp. Both localities constitute the southernmost extent of the genus in Laurasia when the family was likely to have reached its climax in terms of abundance and diversity. 相似文献
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WANG Xuri Jingmai K. O’Connor ZHAO Bo Luis M. Chiappe Gao Chunling Cheng Xiaodong 《《地质学报》英文版》2010,84(2):247-256
<正>We report on a new species of enantiornithine bird from the Lower Cretaceous Qiaotou Formation of northern Hebei,China.The new taxon,Shenqiornis mengi gen.et sp.nov.,possesses several enantiornithine synapomorphies but is unique from other known species.The specimen has a well-preserved skull that reveals new information about enantiornithine cranial morphology.The new taxon possesses a large postorbital with a long tapering jugal process indicating that some enantiornithines may have had a fully diapsid skull,as in Confuciusornis.The tooth morphology of the specimen is unique and likely represents a previously unknown trophic specialization within Enantiornithes. 相似文献
11.
Damien Becker 《Swiss Journal of Geoscience》2009,102(3):489-504
Earliest rhinocerotoids from Switzerland are reviewed on the basis of dental remains from the earliest Oligocene north-central
Jura Molasse localities of Bressaucourt (MP21/22) and Kleinblauen (top MP22). The record in Bressaucourt is restricted to
Ronzotherium and Cadurcotherium, representing Switzerland’s oldest, well-dated post-“Grande Coupure” large mammal association, the only occurrence of Cadurcotherium, and the earliest occurrence of rhinocerotoids in Switzerland. The correlation with high-resolution stratigraphy of this
locality permitted a dating of the fauna to ca. 32.6 Ma, less than a million years after the “Grande Coupure” event. The rhinocerotoids
of Kleinblauen are represented by Epiaceratherium, Ronzotherium and Eggysodon. With the presence of Plagiolophus ministri, they are the only well-dated Swiss post-“Grande Coupure” large mammal assemblage with the persistence of an endemic pre-“Grande
Coupure” taxon. Moreover, the coexistence of Epiaceratherium magnum and E. aff. magnum could indicate a new speciation within the Epiaceratherium lineage around the top of MP22. The rhinocerotoid associations of Bressaucourt with Ronzotherium – Cadurcotherium on the western side of the southernmost Rhine Graben area, and Kleinblauen with Epiaceratherium – Ronzotherium – Eggysodon on the eastern side, respectively, reveal a possible environmental barrier constituted by the Early Oligocene Rhenish sea
and its eventual connection with the Perialpine sea. This one could have separated an arid area in central-eastern France
from a humid area in Switzerland and Germany. These results, combined with the repartition of similar rhinocerotoid associations
in Western Europe, also give new insights into an alternative earliest Oligocene dispersal route of rhinocerotoids from Asia
towards Western Europe via North Italy. 相似文献
12.
Lionel Hautier Hassane Taisso Mackaye Fabrice Lihoreau Pascal Tassy Patrick Vignaud Michel Brunet 《Journal of African Earth Sciences》2009,53(4-5):171-176
New fossil remains of the proboscidean genus Anancus are described. Among them, a complete skull allows us to revisit for the first time the entire Chadian Anancus fossil record. This genus occurred in the Old World from the late Miocene up to the early Pleistocene. The analysis of dental and cranial characters was allowed individual variations from specific characters to be distinguished. In this study we show that Anancus kenyensis and Anancus osiris are very likely synonym taxa which leads us to emend the diagnosis of A. kenyensis. In addition, this study shows that dental characters in anancines lineage are of little significance for biostratigraphical inference, by contrast to previous works. This study brings new data about the phylogenetical and palaeobiogeographical history of the African anancines. 相似文献
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Leptotarsus (sensu lato) lukashevichae sp. nov. is described and illustrated, based on a single but very well preserved female specimen from the Crato Formation of Brazil (Aptian, ca. 112 Ma). Along with other Leptotarsus species recently described from Lower Cretaceous beds of Brazil, Spain, Russia and China, this new species is among the oldest known records of the genus Leptotarsus and the family Tipulidae. 相似文献
14.
Recent excavations in the Middle Triassic Prosanto Formation (Ladinian, Ct. Grisons, Switzerland) have produced new material
of the genus Besania Brough 1939. These specimens show many previously unrecorded details. Some features differ from those of the type species
Besania micrognathus, and we therefore erect a new species, Besania schaufelbergeri sp. nov. This new material has prompted a re-evaluation of the phylogenetic interrelationships of the genus. The taxon seems
to be closely related to basal Halecostomi.
An erratum to this article is available at . 相似文献
15.
Walter Etter 《Swiss Journal of Geoscience》2010,103(2):317-323
Secondary soft-bottom dwellers evolved several times in the Arcoida. These include semi-infaunal endobyssate taxa and free-burrowing
species. The Jurassic arcoid bivalve Grammatodon inaequivalvis (Goldfuss, 1837) is remarkable for showing different sculptures on its left and right valve. A functional analysis of the shell points to
a reclining mode of life on soft bottoms. This interpretation is corroborated by the occurrence of this species in very fine-grained
sediments, and by taphonomic patterns such as “butterflied” preservation. It is proposed here that this species was resting
on its left valve on the sediment, probably without byssal attachment. This reclining mode of life of G. inaequivalvis was hitherto undescribed from soft-bottom dweller arcoid bivalves. 相似文献
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《Proceedings of the Geologists' Association. Geologists' Association》2017,128(4):659-674
The impact of mass extinctions on insect evolution is debated, so investigating taxa that span a crisis is important for understanding such large-scale environmental perturbations. The beetle genus Holcoptera has been found in deposits from the Late Triassic: Norian to the Early Jurassic: Sinemurian of England and the United States, and possibly Italy. Historical collections of Rev. P.B. Brodie and J.F. Jackson were re-examined and the ages of British localities reviewed, US collections were re-interpreted, and new material from the Dorset Coast was considered. Holcoptera schlotheimi and Holcoptera confluens are synonymised based on morphological similarities; Holcoptera giebeli remains distinct and a new complete specimen confirms the placement of this genus in the family Coptoclavidae. Three new species are described: Holcoptera pigmentatus sp. nov. from the Penarth Group of Warwickshire, Holcoptera alisonae sp. nov. (based on the rejected neotype of H. schlotheimi) from the Lower Lias of Dorset and Holcoptera solitensis sp. nov. from the Newark Supergroup of Virginia. H. schlotheimi and H. giebeli are known from the Late Triassic Penarth Group and Early Jurassic Lias Group and so survived the end-Triassic extinction, whereas H. alisonae and H. pigmentatus are only known from the Lias Group. H. solentensis is the oldest described species in this genus and is not known from any other locality. 相似文献
18.
《Proceedings of the Geologists' Association. Geologists' Association》2022,133(2):148-153
A newly discovered ammonite of the genus Hyperlioceras from the Lincolnshire Limestone Formation of Eastern England enables the biostratigraphical position of the principal building stone of Lincoln Cathedral: the ‘Silver Bed’ variant of Lincoln Stone (Lower Lincolnshire Limestone) to be precisely dated as subsectum biohorizon of the Lower Bajocian, Discites Zone. Ammonites are extremely rare in this formation thus the impetus to record it here and provide a firm date for strata in which it occurred following its discovery. The lithostratigraphical provenance of the specimen is briefly discussed and evidence provided to support the conclusion. 相似文献
19.
E. Yu. Golubkova E. G. Raevskaya A. B. Kuznetsov 《Stratigraphy and Geological Correlation》2010,18(4):353-375
Both published and original data are used for the analysis of the stratigraphic position and taxonomic characteristics for
acanthomorphic microfossils of the Pertatataka type in Lower Vendian sediments of the central and southeastern Siberian Platform
and its surrounding structures. Four taxonomically different microbiotas are distinguished in sections of the Nepa-Botuoba,
Fore-Patom; Syugdzher, Anabar, Zhuya-Lena, and Berezovo lithotectonic zones: two diverse (Nepa and Ura) and two impoverished
(Otradnino and Torga) each including diagnostic Early Vendian taxa. Beyond the Siberian Platform, genera and species characterizing
these microbiotas occur in single assemblages and represent diagnostic taxa of the second (Tc-Sr-Vl) and third (Ti-Cg-Mp)
zones of the acritarch scale proposed by Australian geologists as a biostratigraphic basis for subdividing the Ediacarian
of the Standard stratigraphic scale (SSS). In the Russian General stratigraphic scale, the distribution of Pertatataka acritarchs
corresponds to the Lower Vendian. The appearance and mass development of acanthomorphic microorganisms represents a global
biological event, which should be taken into consideration as a biostratigraphic criterion for defining the Vendian System.
For substantiating age, the following species among diagnostic Lower Vendian forms of East Siberia should be used: Appendisphaera grandis, “Appendisphaera” tabifica, A. tenuis, Ceratosphaeridium glaberosum, Dicrospinosphaera virgata, Multifronsphaeridium
pelorium, “Polygonium” cratum, Tanarium conoideum, Variomargosphaeridium litoschum, and Talakania obscura. These taxa are readily recognizable, morphologically stable, and characterized by their wide lateral distribution and relatively
narrow stratigraphic range. Their occurrence in the upper part of the Dal’nyaya Taiga Group of the Baikal-Patom region indicates
that host sediments should be attributed to the Lower Vendian, not the Upper Riphean as is currently accepted. 相似文献
20.
An incomplete rostrum of a platypterygiine ichthyosaur (IGVR 94574) has recently been found near Tregnago (Verona, Italy), in the Lessini Mts. This is the first Cretaceous ichthyosaurian fossil found in Italy outside the northern Apennines, where fragmentary remains have been recovered since the 19th century.IGVR 94574 is a mid-distal rostral fragment infilled by a white, fine-grained limestone matrix. It consists of the premaxilla, nasal, vomer, dentary, and splenial, together with 20 teeth.Even if the exact horizon of provenance is unknown, analysis of the microfossil content of the matrix (planktonic foraminifera and calcareous nannofossils) allowed us to assign it to the lower part of the upper Albian. This is also the first Cretaceous ichthyosaur in Italy with a precise age: all previously reported fossils from the Apennines could not be dated due to the complete absence of microfossils in the surrounding matrix.We assign IGVR 94572 to Platypterygiinae; generic specification is not possible pending the taxonomic revision of the genus Platypterygius.Finally, the Tregnago rostrum is strikingly similar to the specimen IPUM 30139 from Gombola (Modena, Italy), stored in the collections of the Paleontological Museum of Modena and Reggio Emilia University and also attributable to a platypterygiine ichthyosaur. The comparison between these two fossils reveals the teeth are very similar both in shape and size. 相似文献