Lusitanisuchus, a new generic name for Lisboasaurus mitracostatus (Crocodylomorpha: Mesoeucrocodylia), with a description of new remains from the Upper Jurassic (Kimmeridgian) and Lower Cretaceous (Berriasian) of Portugal

2004 ◽  
Vol 41 (10) ◽  
pp. 1259-1271 ◽  
Author(s):  
Daniela Schwarz ◽  
Regina Fechner

Lusitanisuchus mitracostatus is a small mesoeucrocodilian crocodylomorph from the Upper Jurassic (Kimmeridgian) of Guimarota–Leiria in Portugal, which was originally described as an anguimorph lizard (Lisboasaurus mitracostatus Seiffert, 1970) based on jaw fragments and isolated teeth. A recent reexamination of the crocodylomorph material of Guimarota yielded new skull and dentary remains assignable to Lusitanisuchus mitracostatus. The new skull material not only enables for the first time a skull reconstruction of this taxon, but also leads to renaming and reclassifying Lisboasaurus mitracostatus. Teeth of Lusitanisuchus are also reported from the locality Porto Dinheiro–Lourinhã, Early Cretaceous (Berriasian) of Portugal. The presence of this crocodylomorph taxon in two Portuguese localities suggests its occurence in the Lusitanian Basin during the Kimmeridgian to the Berriasian.

2013 ◽  
Vol 64 (4) ◽  
pp. 291-304 ◽  
Author(s):  
Dandan Wei ◽  
Dong Ren

Abstract Although cockroaches were the dominant insects in various Paleozoic and Mesozoic insect assemblages, their general morphology was extremely conservative. One of the most common of them, the Jurassic-Cretaceous family Mesoblattinidae, is described here for the first time on the basis of completely preserved specimens. Ninety-two specimens of Perlucipecta aurea gen. et sp. n. reveal details of head, mandible, male tergal glands and terminal hook; cercal, leg and antennal sensilla. Its congener, P. vrsanskyi is described from the same sediments of the Yixian Formation (Upper Jurassic-Lower Cretaceous). The forewing venation variability of P. aurea, analysed for the first time in this family is nearly identical (CV = 6.23 %) with variability of two species of family Blattulidae that occur at the same locality (CV = 6.22 %; 5.72 %). The transitional nature of morphological characters represented by asymmetry between left and right wings (simple/branched forewing SC and hind wing M) in P. aurea documents the phylogenetic relation between the families Mesoblattinidae and Ectobiidae


2020 ◽  
Author(s):  
Kseniya Mikhailova ◽  
Victoria Ershova ◽  
Mikhail Rogov ◽  
Boris Pokrovsky ◽  
Oleg Vereshchagin

<p>Glendonites often used as paleoclimate indicator of cold near-bottom temperature, as these are calcite pseudomorphs of ikaite, a metastable calcium carbonate hexahydrate, precipitates mostly under low temperature (mainly from 0-4<sup>o</sup>C) and may be stabilized by high phosphate concentrations that occurs due to anaerobic oxidation of methane and/or organic matter; dissolved organic carbon, sulfates and amino acid may contribute ikaite formation as well.  Therefore, glendonites-bearing host rocks frequently include glacial deposits that make them useful as a paleoclimate indicator of near-freezing temperature.</p><p>Our study is based on material collected from five wells drilled in eastern Barents Sea: Severo-Murmanskaya, Ledovaya – 1,2; Ludlovskaya – 1,2. The studied glendonites, mainly represented by relatively small rhombohedral pseudomorphs (0,5-2 cm) and rarely by stellate aggregates, collected from Middle Jurassic to Lower Cretaceous shallow marine clastic deposits. They scattered distributed throughout succession. Totally 18 samples of glendonites were studied. The age of host-bearing rocks were defined by fossils: bivalves or ammonites, microfossils or dinoflagellate. Bajocian-Bathonian glendonites were collected from Ledovaya – 1 and Ludlovskaya – 1 and 2 wells; in addition to these occurrences Middle Jurassic glendonites are known also in boreholes drilled at Shtockmanovskoe field. Numerous ‘jarrowite-like’ glendonites of the Middle Volgian (~ latest early Tithonian) age were sampled from Severo-Murmanskaya well. Unique Late Barremian glendonites were found in Ledovaya – 2 well.</p><p>δ<sup>18</sup>O values of Middle Jurassic glendonite concretions range from – 5.4 to –1.7 ‰ Vienna Pee Dee Belemnite (VPDB); for Upper Jurassic – Lower Cretaceous δ<sup>18</sup>O values range from – 4.3 to –1.6 ‰ VPDB; for Lower Cretaceous - δ<sup>18</sup>O values range from – 4.5 to –3.4 ‰ VPDB. Carbon isotope composition for Middle Jurassic glendonite concretions δ<sup>13</sup>C values range from – 33.3 to –22.6 ‰ VPDB; for Upper Jurassic – Lower Cretaceous δ<sup>13</sup>C values range from – 25.1 to –18.4 ‰ VPDB; for Lower Cretaceous - δ<sup>13</sup>C values range from – 30.1 to –25.6 ‰ VPDB.</p><p>Based on δ<sup>18</sup>O data we supposed that seawater had a strong influence on ikaite-derived calcite precipitation. Received data coincide with δ<sup>18</sup>O values reported from other Mesozoic glendonites and Quaternary glendonites formed in cold environments. Values of δ<sup>13</sup>C of glendonites are close to bacterial sulfate reduction and/or anaerobic oxidation of methane or organic matter. Glendonites consist of carbonates forming a number of phases which different in phosphorus and magnesium content. Mg-bearing calcium carbonate and dolomite both include framboidal pyrite, which can indicate (1) lack of strong rock transformations activity and (2) presence of sulfate-reduction bacteria in sediments.</p><p>To conclude, Mesozoic climate was generally warm and studied concretions indicate cold climate excursion in Middle Jurassic, Upper Jurassic-Early Cretaceous and Early Cretaceous.</p><p> </p><p>The study was supported by RFBR, project number 20-35-70012.</p>


2018 ◽  
Vol 40 (1) ◽  
pp. 182 ◽  
Author(s):  
A. Photiades ◽  
N. Carras ◽  
V. Bortolotti ◽  
M. Fazzuoli ◽  
G. Principi

Three stratigraphical sections from eastern Vourinos (Rhodiani area) to eastern Vermion massifs revealed the same age of the latérite events affecting the serpentinized ophiolite complex after its emplacement on the Pelagonian domain. All of them consist from their base upwards of serpentinized harzburgite slivers with lateritic unconformities on the top, followed by transgressive upper Lower Cretaceous neritic limestones. At Kteni locality (Rhodiani area), a laterite horizon, lying on top of serpentinites, is covered by transgressive neritic limestones with Salpingoporella urladanasi, assigning a Barremian - Albian age, followed by Orbitolinidae limestones. At Tsimodia locality (NNW to the previous), the latente horizon, lying on karstified Upper Jurassic reef limestones (which are the top member of a carbonate platform body tectonically lying on the ophiolites), is trans gres s ively overlain by iron-rich pisolith levels and Aptian limestones of the wackes tone-muds tone type, also containing Salpingoporella urladanasi, followed by Cenomanian Orbitolina limestones. Finally, the third examined locality, further north-eastward to the previous, is situated at the eastern slopes of Vermion massif and more precisely at the NWpart of Koumaria village. There, it can again be observed that the lateritized serpentinite slivers are overlain transgress ively by neritic limestones with Salpingoporella urladanasi, passing upwards into Upper Cretaceous recrystallized limestones with Orbitolinidae and rudist fragments and, finally, toflysch deposition. These features allow to recognize that the emersion and the consecutive lateritization of the thrust-emplaced ophiolites in Vourinos and Vermion massifs in the northern Pelagonian domain, starting from the Latest Jurassic, was followed by a marine transgression beginning from the Barremian - Albian, firstly under restricted and brackish carbonate platform conditions, marked by the presence of the dasycladalean alga Salpingoporella urladanasi, followed by normal salinity carbonate platform conditions. The neritic sedimentation was stable until the Early Cenomanian. Subsequently, a deepening, earlier at Vourinos and later at Vermion, resulted in deposition of pelagic and turbiditic carbonates and then offlysch.


2014 ◽  
Vol 65 (4) ◽  
pp. 285-292 ◽  
Author(s):  
Shih-Wei Lee

Abstract Mantodea are very rare in the fossil record. 28 fossil species are reported since the earliest occurrence of mantodeans in the Upper Jurassic (Tithonian). Here, I describe Cretophotina santanensis n. sp. from the Aptian (Lower Cretaceous) Crato Formation of Chapada do Araripe (northeastern Brazil). This species is characterized by long antenna and primitive raptorial forelegs. Morphological characters shared with the living genus Chaeteessa would support its assignment to the family Chaeteessidae. The tropical occurrence of the Early Cretaceous genus Cretophotina in Gondwana, together with occurrences of the genus Chaetessa from subtropical and temperate zones of Laurasia, implies that members of the family Chaeteessidae achieved nearly cosmopolitan distribution during the Early Cretaceous.


2021 ◽  
pp. pygs2021-005
Author(s):  
Roderick D. Black ◽  
Paul Dodsworth

At Middlegate Quarry, the Carstone Formation is an approximately 0.8 m thick unit of oolitic ferruginous sandstone. It rests unconformably on the lower Kimmeridge Clay Formation (KCF) and is overlain by the Hunstanton Formation (Red Chalk) with an apparently gradational junction. Marine dinoflagellate cysts (dinocysts) are present at a concentration of 9,520 to 13,600 specimens per gramme in the 0.15 m of KCF below the unconformity, and include taxa that confirm ammonite evidence for the intra-Lower Kimmeridgian Substage (Upper Jurassic, Cymodoce Ammonite Zone). A rich recovery of well-preserved Lower Cretaceous palynomorphs is reported for the first time from the overlying Carstone. Reworking of mudstone from the KCF into the formation appears to have provided a local argillaceous preservation matrix at Middlegate. The basal 0.15 m is dominated by palynomorphs derived from the KCF but the interval from 0.15 m to 0.55 m above the unconformity mainly contains indigenous Lower Cretaceous palynomorphs. Dinoflagellate cysts are present in the Carstone at an average concentration of 454 specimens per gramme, and include taxa that probably have stratigraphical range bases above the Aptian – Albian stage boundary; Cyclonephelium compactum, Cyclonephelium intonsum, Endoscrinium heikeae, Leptodinium cancellatum (consistent), Stephodinium coronatum and Stephodinium spinulosum. The additional presence of taxa with range tops / event tops in the Lower Albian Tardefurcata Ammonite Zone (common Cauca parva, frequent Canninginopsis monile and Kleithriasphaeridium eoinodes, and rare Dingodinium albertii, Discorsia nannus and Kiokansium prolatum) indicate probable assignment to this zone. The new palynological data support previous macrofossil (brachiopod) study of the Carstone at Middlegate and nearby Melton Bottom Quarry which tentatively assigns its highest part to the Tardefurcata Zone. The palynological and palynofacies assemblages are interpreted to confirm a relatively proximal to shoreline site of deposition, possibly inner to middle neritic.Supplementary material: One pdf file, with quarry photographs and a palynological distribution chart, is available at https://doi.org/10.6084/m9.figshare.c.5538977


Fossil Record ◽  
2000 ◽  
Vol 3 (1) ◽  
pp. 77-86
Author(s):  
H. Jähnichen ◽  
E. Kahlert

Nymph-fragments (and detached cerci) of the may-fly <i>Ephemeropsis trisetalis</i> Eichwald and the water-beetle <i>Coptoclava longipoda</i> Ping, a coleopteran and a shell-fragment of the conchostracan <i>Turfanograpta</i> sp. are described for the first time from Lower Cretaceous paper-shales of Bajan-Khongor, Mongolia. The assemblage <i>Lycoptera</i> (fishes included in the Order Osteoglossiformes, Fam. Lycopteridae)-<i>Ephemeropsis-Coptoclava</i> correlates with Lower Cretaceous deposits in Transbaikalia, Mongolia and North-Eastern China. The fern-species <i>Adiantopteris sewardi</i> (Yabe) Vassiljevskaja and <i>Adiantopteris toyoraënsis</i> (Oishi) Vassiljevskaja occur in fine-sandstones of Bajan-Khongor (Jähnichen & Kahlert 1972). Their importance as Early Cretaceous flora-elements is discussed. <br><br> Larvenfragmente und isolierte Cerci der Eintagsfliege <i>Ephemeropsis trisetalis</i> Eichwald und vom Wasserkäfer <i>Coptoclava longipoda</i> Ping, und ein Schalenfragment der Conchostrake <i>Turfanograpta</i> sp. werden erstmalig aus unterkretazischen Dysodilen von Bajan-Khongor in der Mongolei beschrieben. Die Faunengemeinschaft <i>Lycoptera</i> (Fische der Ordnung Osteoglossiformes, Fam. Lycopteridae)-<i>Ephemeropsis-Coptoclava</i> tritt gleichzeitig in unterkretazischen Ablagerungen von Transbaikalien, Mongolei, und im nordöstlichen China auf. Das Vorkommen der Farnspezies <i>Adiantopteris sewardi</i> (Yabe) Vassil-jevskaja und <i>Adiantopteris toyoraënsis</i> (Oishi) Vassiljevskaja in Feinsandsteinen von Bajan-Khongor (Jähnichen & Kahlert 1972) und deren Wichtigkeit als unterkretazische Florenelemente werden diskutiert. <br><br> doi:<a href="http://dx.doi.org/10.1002/mmng.20000030104" target="_blank">10.1002/mmng.20000030104</a>


2020 ◽  
Vol 50 ◽  
pp. 2-10
Author(s):  
Chan-gyu Yun

A large tooth of theropod dinosaur that was recovered from the Hasandong Formation (Lower Cretaceous; Aptian-Albian) in Daedo island, Hadong Couty, South Gyeongsang Province of South Korea is redescribed. Although the tooth was misidentified as a "Prodeinodon"-like megalosaurid theropod at the first time, detailed comparisons with known theropod dentition anatomy strongly indicate that this tooth belongs to an Acrocanthosaurus-like basal carcharodontosaurid theropod. This referral is supported by its combination of large size, ovoid-shaped cervix outline, mesial carina that does not reach the cervix, labially displaced distal carina and large number of denticles. This tooth is different from other carcharodontosaurid teeth from the same formation in several anatomical aspects (e.g., smaller overall size, presence of transverse lines adjacent to the distal carina, presence of interdenticular sulci in distal carina, denticle densities, crown basal ratio), indicating that carcharodontosaurid diversity in the Early Cretaceous of Korea could have been higher, although these differences may represent positional or individual variations. The presence of Acrocanthosaurus-like theropod teeth (e.g., "Prodeinodon", "Wakinosaurus") from early Cretaceous deposits (Valanginian-Cenomanian) of South Korea, Japan, Mongolia and China indicates that North American Acrocanthosaurus atokensis possibly represents a form that immigrated from the Asia.


Zootaxa ◽  
2009 ◽  
Vol 2072 (1) ◽  
pp. 31-55 ◽  
Author(s):  
PAUL M. BARRETT ◽  
FENG-LU HAN

A detailed description of the skull and mandible of the Chinese cerapodan ornithischian dinosaur Jeholosaurus shangyuanensis (Lower Cretaceous, Yixian Formation) is presented for the first time and this information is used to reassess its phylogenetic position. Jeholosaurus can be distinguished from all other cerapodans on the basis of one autapomorphy (a row of small foramina on the nasal) and a character combination that is unique among ornithischians. Previously undescribed specimens add considerably to our knowledge of Jeholosaurus, providing new insights into its anatomy and ontogeny. Revised character scores increase the resolution of phylogenetic hypotheses and provide additional support for placement of Jeholosaurus within Ornithopoda.


2003 ◽  
Vol 1 ◽  
pp. 231-246 ◽  
Author(s):  
Peter Japsen ◽  
Peter Britze ◽  
Claus Andersen

The Danish Central Graben is part of the mainly Late Jurassic complex of grabens in the central and southern North Sea which form the Central Graben. The tectonic elements of the Danish Central Graben in the Late Jurassic are outlined and compared to those in the Early Cretaceous based on reduced versions of published maps (1:200 000), compiled on the basis of all 1994 public domain seismic and well data. The Tail End Graben, a half-graben which stretches for about 90 km along the East North Sea High, is the dominant Late Jurassic structural feature. The Rosa Basin (new name) is a narrow, north–south-trending basin extending from the south-western part of the Tail End Graben. The Tail End Graben ceased to exist as a coherent structural element during the Early Cretaceous and developed into three separate depocentres: the Iris and Gulnare Basins to the north and the Roar Basin to the south (new names). The Early Cretaceous saw a shift from subsidence focused along the East North Sea High during the Late Jurassic to a more even distribution of minor basins within the Danish Central Graben. The depth to the top of the Upper Jurassic – lowermost Cretaceous Farsund Formation reaches a maximum of 4800 m in the northern part of the study area, while the depth to the base of the Upper Jurassic reaches 7500 m in the Tail End Graben, where the Upper Jurassic attains a maximum thickness of 3600 m. The Lower Cretaceous Cromer Knoll Group attains a maximum thickness of 1100 m in the Outer Rough Basin.


1993 ◽  
Vol 130 (4) ◽  
pp. 533-542 ◽  
Author(s):  
Jingeng Sha ◽  
Franz Theodor Fürsich

AbstractThe biostratigraphic significance of the bivalves Buchia and Aucellina in northeast China is assessed. Buchia is abundant in four assemblages of the Dong'anzhen Formation, spanning the Jurassic-Cretaceous boundary: B. russiensis-B. fischeriana (Middle Volgian), B. fischeriana-B. unschensis (Upper Volgian), B. volgensis-B. cf. subokensis-B. cf. okensis-B. unschensis (Berriasian), and B. pacifica (Lower Valanginian). Aucellina is common in two Middle Barremian-Aptian assemblages: A. caucasica-A. aptiensis-A. jeletzkii in the lower part of the Upper Yunshan Formation, Longzhaogou Group, and in the lower part of the Chengzihe Formation, Jixi Group; A. cf. caucasica-A. cf. aptiensis in the upper part of the Upper Yunshan Formation. These assemblages can be correlated on a global scale and are particularly significant in dating the Early Cretaceous coalbearing measures of eastern Heilongjiang.


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