Charophyte biostratigraphy of the non-marine Lower Cretaceous in the Central Tunisian Atlas (North Africa): Palaeobiogeographic implications

The chronostratigraphic framework of the non-marine deposits of the Central Tunisian Lower Cretaceous (Kebar Formation) is reviewed from a biostratigraphic viewpoint. The outcrops located in the Jebel Kebar, Jebel Ksaïra and Jebel Koumine localities provided charophyte assemblages belonging to two biochronozones: Ascidiella cruciata-Pseudoglobator paucibracteatus (upper Barremian–lower Aptian) and Clavator grovesii lusitanicus (upper Aptian–lower Albian). Clavatoraceans from the upper Barremian–lower Aptian in the Tunisian Atlas are reported here for the first time. The assemblage consists of Atopochara trivolvis var. triquetra, Ascidiella iberica var. inflata, Globator maillardii var. trochiliscoides, Globator maillardii var. biutricularis, Echinochara peckii var. lazarii, Clavator harrisii var. harrisii and Clavator harrisii var. reyi. In addition, a new characean species, Mesochara magna nov. sp. Trabelsi and Martín-Closas, is described herein. The results show that the Kebar Formation is diachronous in Central Tunisia, with a more complete record to the north (Jebel Koumine) than in the type locality (Jebel Kebar). Barremian–Aptian diapiric activity is proposed as the factor that controls the diachronous nature of this formation.The late Barremian–early Aptian charophyte assemblages from the Kebar Formation display strong affinities with the contemporaneous floras of the European basins, thus suggesting that intense supraregional floristic exchanges occurred between the Tethyan islands scattered throughout what is now Western Europe and North Africa. The biogeographic distribution of these charophytes leads to the hypothesis that the peri-Tethyan Archipelago acted as an effective bridge for the intercontinental exchanges of these plants between Laurasia and Gondwana.     

Geological and Palaeontological context of three new Barremian (Lower Cretaceous) vertebrate sites in the Iberian Peninsula (Cuenca Province,Central Spain)

Three new Lower Cretaceous vertebrate sites (Vadillos-1, Vadillos-2, El Tobar) have been recently discovered and studied in the Cuenca Province (Central Spain). They are located in deposits of “Wealden” facies belonging to the El Collado Sandstone and Clay Formation. In these outcrops, micro and macroremains corresponding to plants, invertebrates and vertebrates have been collected and subsequently assigned to macrophytes, charophytes (e.g., Atopochara trivolvis triquetra, Globator maillardii trochiliscoides, Clavator harrisii harrisii), ostracods (e.g., Cypridea gr. modesta, Cypridea cf. C. isasae, Cypridea sp. aff. C. moneta, Cypridea sp. 1, Cypridea sp. 2), molluscs (Unionoida, Viviparus sp.), fishes, amphibians, turtles (cf. Eucryptodira), crocodyliforms (Neosuchia) and dinosaurs (ankylosaurs, ornithopods, theropods). Among the vertebrate remains, scales, teeth, plates, osteoderms, phalanges, ribs, vertebrae and other incomplete bones, as well as eggshell fragments have been identified. This rich and diverse assemblage was deposited in an upper Barremian alluvial-palustrine muddy floodplain crossed by braided sandy channels.     

A review of the Late Jurassic–Early Cretaceous charophytes from the northern Aquitaine Basin in south-west France

Late Jurassic and Early Cretaceous charophyte assemblages from the northern part of the Aquitaine Basin in south-west France are reviewed here to understand their palaeoecological, palaeobiogeographical and biostratigraphic features. Three sites were studied: the Tithonian-lower Berriasian of Chassiron, and the Berriasian of Cherves-de-Cognac and Angeac-Charente. Abundant porocharaceans, less abundant clavatoraceans and scarce characeans recorded in Cherves-de-Cognac and Angeac-Charente indicate that brackish water environments were substituted by freshwater environments eastwards. The occurrence of Clavator grovesii var. grovesii and morphotypes intermediate with C. grovesii var. discordis in the same areas is significant from a biostratigraphic viewpoint, since these species belong to the Maillardii, Incrassatus and Nurrensis European charophyte biozones, representing the Berriasian. This observation refutes a previous dating of the Angeac-Charente site and highlights the absence of Hauterivian–Barremian records in northern Aquitaine, which is in contrast to the more complete Lower Cretaceous record in southern Aquitaine. These contrasting records could be due to differences in the available sedimentary space produced by the opening of the Bay of Biscay during the Barremian.     

Charophytes from the Upper Berriasian of the Western Interior Basin of the United States

A charophyte flora from the Upper Berriasian is described from the Lakota (Black Hills, South Dakota) and Cedar Mountain formations (San Rafael Swell, Utah) of the Western Interior Basin, United States of America. Whereas the latter is dominated by monotonous assemblages of the clavatoracean Nodosoclavator bradleyi (Harris, 1939), found in temporary lakes within palustrine facies, the flora of the Lakota Formation consists of more varied assemblages of the clavatoraceans N. bradleyi (Harris, 1939), Clavator grovesii grovesii Harris 1939, C. bilateralis Peck 1957 and early characeans (Mesochara sp. or Tolypella sp.). This flora was found in deposits related to permanent lakes in fluvial floodplains, i.e. lacustrine marls and limestones that do not show any evidence of subaerial exposure. To date, little is known about C. bilateralis, we provide a new definition on the basis of its particular structure, which shows lateral bract-cell units with a pinnate arrangement. This species appears to be endemic to North America and stratigraphically limited to the earliest Cretaceous. C. grovesii grovesii is part of a long-lasting charophyte lineage, which until now was considered to have originated in the Central Tethyan Archipelago (Europe) during the Early Berriasian, about 145 Ma, and limited to Eurasia until most of the Early Cretaceous. The new data presented here suggest that during the Berriasian this species was very broadly distributed, comprising North America, Europe and China.     

Ichnological evidence of marine incursions in the lacustrine–palustrine Bembridge Limestone Formation (Eocene), Isle of Wight,southern England

Trace fossils are described from the Eocene Bembridge Limestone Formation from the Isle of Wight and used to constrain the paleoenvironmental interpretation. The lacustrine–palustrine succession contains three limestone beds, which are separated by clay and marl. The middle and upper limestone beds reveal complex burrow systems developed at their top. Based on their characteristics, these burrow systems are assigned to the ichnotaxon Balanoglossites triadicus Mägdefrau, which is associated with the shallow superficial grooves Sulcolithos variabilis Knaust. B. triadicus is a common marine trace fossil mainly known from shallow-marine carbonate successions throughout the Phanerozoic. It is accompanied by other marine ichnotaxa such as Arachnostega gastrochaenae Bertling, Gastrochaenolites isp. aff. G. ornatus Kelly and Bromley, Spongeliomorpha iberica Saporta and Thalassinoides suevicus (Rieth). This ichnological evidence confirms the occurrence of short-term marginal-marine incursions in a predominantly lacustrine to palustrine environment.     

Charophytes du Crétacé moyen et données nouvelles sur l'Evolution des Clavatoracées

La découverte de nouveaux gisements dans le Sud de la France révèle la persistance, dans le Cénomanien, d'Embergerella cruciata, Atopochara restricta et A. brevicellis (Clavatoraceae). Une parenté entre les genres Embergerella (Barrémien-Cénomanien) et Septorella (Maastrichtien) est envisagée sur la base d'une nouvelle interprétation de la structure de l'utricule. Pour la première fois, des représentants de la famille des Characeae sont décrits dans le Cénomanien: Peckisphaera revesti n. sp. et le Turonien: Mesochara fusiformis n. sp. Indications biostratigraphiques: dans l'état actuel des connaissances sur les flores de Charophytes du Crétacé moyen, seul le Cénomanien est bien caractérisé, par A. multivolvis à laquelle s'ajoute maintenant une nouvelle association de quatre espèces; l'Albien et le Turonien, pour lesquels des précisions sont apportées, restent toutefois encore mal individualisés.The discovery of new localities in the South of France shows that Embergerella cruciata, Atopochara restricta and A. brevicellis (Clavatoraceae) continued into the Cenomanian. A relationship between the genera Embergerella (Barremian-Cenomanian) and Septorella (Maastrichtian) is suggested on the basis of a new interpretation of the structure of the utricle. Representatives of the family Characeae are described for the first time, Peckisphaera revesti n. sp. in the Cenomanian and Mesochara fusiformis n. sp. in the Turonian. Biostratigraphic information: in the present state of knowledge of Middle Cretaceous Charophyte floras, only the Cenomanian is well characterized, by A. multivolvis to which is now added a new association of four species. Although new information is presented on the Albian and Turonian, they are still inadequately understood.     

Iberanaia iberica: The first record of the Trigonioidoidea Bivalvia: Unionoida from the Lower Cretaceous of Teruel, Spain

The first record of the superfamily Trigonioidoidea (Order: Unionoida) from the Lower Cretaceous of Teruel, Spain is described and compared to known taxa from Europe and Asia. This is a new record of the Trigonioidoidea from Europe, following material described from the Barremian of the Isle of Wight (southern England) and Aptian-Barremian from Iberian Range (Spain). The new material, recorded from the Albian of the Escucha Formation (“Barriada” Member) in Utrillas (Teruel, northeastern of Spain), comprises four specimens. Analysis of the main morphological characters including anterior musculature, dentition, and ornamentation indicates that this material constitutes a new genus and species, Iberanaia iberica. The palaeoenvironment in which the bivalves lived corresponds to a fluvial-palustral setting connected to a deltaic system.     

New ornithopod footprints from the Lower Cretaceous Kitadani Formation,Fukui, Japan: Ichnotaxonomical implications

Two ichnogenus of “large-sized” ornithopods are found from the Lower Cretaceous (Aptian) Kitadani Formation in central Japan. Caririchnium isp. is characterized by the longer pes print than its width with strong mesaxony. Amblydactylus isp. is characterized by the wider pes print than its length with weak mesaxony. In the northern hemisphere, Caririchnium-type footprints are known from the Berriasian–Cenomanian strata, whereas Amblydactylus-type footprints are known from the Barremian–Maastrichtian strata. It is consistent with the temporal and geographic distribution of non-hadrosauroid iguanodontians and basal hadrosauroids. It suggests that footprint length-width ratio and mesaxony are important factors to indicate trackmakers (basal iguanodontian or hadrosauroid). Two “large-sized” ornithopod ichnogenus from the Kitadani Formation is also consistent with two iguanodontians from same site. It indicates a high diversity of the Kitadani ichnofauna and its importance to elucidate the ecosystem of the Kitadani Formation.     

An ichthyosaur (Reptilia: Ichthyosauria) specimen from the Lower Cretaceous (Berriasian) Spilsby Sandstone Formation of Nettleton,Lincolnshire, UK

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.     

Ammonoids (Desmoceratoidea and Silesitoidea) from the Late Barremian of Boljetin,eastern Serbia

The subject of the study was the taxonomy of the ammonite fauna from the Upper Barremian marls and marly limestones of the Donji Milanovac Formation outcropped at the Boljetin Hill (Danubicum Unit). These sediments yielded a rich ammonite fauna which included also representatives of two superfamilies, Desmoceratoidea and Silesitoidea. The Desmoceratoidea include the family Barremitidae to which belong Plesiospitidiscus boljetinensis n. sp., Barremites balkanicus, Montanesiceras breskovskii n. sp., Barremitites strettostoma strettostoma and B. panae, Torcapella serbiensis n. sp., Pseudohaploceras tachthaliae, P. portaeferreae, Melchiorites haugi and Patruliusiceras cf. crenelatum. The Silesitoidea are represented by the family Silesitidae with Silesites trajani and S. seranonis. With the exception of the new, possibly endemic species, Plesiospitidiscus boljetinensis n. sp., Montanesiceras breskovskii n. sp., and Torcapella serbiensis n. sp., these taxa are common in the Tethyan regions. The studied deposits with ammonites belong to the lower part of the Late Barremian, in particular to the upper part of the Toxancyloceras vandenheckii ammonite Zone up to the lower part of the Imerites giraudi Zone.     

黑龙江省东部中侏罗世至早白垩世沟鞭藻组合序列

对近二十年来黑龙江省东部海相侏罗纪—白垩纪沟鞭藻地层资料进行了综合研究 ,首次为该地区建立起侏罗纪—白垩纪沟鞭藻地层序列 ,主要包含 7个组合带 (含 3个高峰带 ) ,其中绥滨地区 Callovian— Valanginian期有 4个带 ;鸡西盆地早白垩世也有 4个带 (其中包括与绥滨地区早白垩世早期同时异相的一个 )。它们自下而上为 :1)绥滨组的 Pareodinia ceratophora- N annoceratopsispellucida组合带 ;　 2 )东荣组下部的 Gonyaulacysta jurassica组合带 (高峰带 ) ;　 3)东荣组上部的 Amphorula delicata组合带 ;　 4 )东荣组最上部的海相 Oligosphaeridium pul-cherrimum组合带 (高峰带 )或鸡西盆地滴道组的微咸水—半咸水的 Vesperopsis didaoensis- L agenorhytis granoru-gosa组合带 ,两者为同时异相关系 ;　 5 )城子河组下部海相层的 Odontochitina operculata- Muderongia tetracantha组合带 (该带可进一步划分出 2个亚组合带 ) ;　 6 )城子河组上部海相层的 Canningia reticulata组合带 ;　 7)穆棱组下段的 Cribroperidinium ?parorthoceras组合带 (高峰带 )。     

Geochronology and Landscape Development Along the Middle Río Quequén Grande at the Paso Otero Locality,Pampa Interserrana,Argentina

The Paso Otero Locality is a cluster of archaeological sites within the middle Río Quequén Grande basin located in the northern coastal plain of Argentina. The valley fill is Holocene alluvial, eolian, and palustrine sediment, including the top of the Guerrero Member (∼10,000 ¹⁴C yr B.P.), upper Río Salado Member (∼3000 ¹⁴C yr B.P.), and lower La Postrera Formation (∼2400 ¹⁴C yr B.P.). Regional soils include the Puesto Callejón Viejo (10,000 to 9400 ¹⁴C yr B.P.) and the Puesto Berrondo (∼4800 ¹⁴C yr B.P.). Radiocarbon sampling of buried A‐horizons on both sides of the river produced 17 dates considered reliable. The geoarchaeological information allows exploration of the implications for the formation of the archaeological record. Similar geological processes of differential intensity have resulted in contexts of different archaeological resolution and integrity. The Paso Otero Locality provides both a local and regional view of late Quaternary events and processes for the middle basin of the Río Quequén Grande.     

First record of a weevil (Coleoptera: Nemonychidae) from the Lower Cretaceous (Wealden) of southern England

A new weevil, Oxycorynoides bucklowae sp. nov. is described from the lower Barremian Upper Weald Clay Formation of south Surrey, UK. The new species differs from other species of the nominative subgenus in the large body size; large, elongate eyes; and distinctly curved rostrum. It approaches but is also distinguished from the Berriasian-Hauterivian Oxycorynoides mongolicus Zherikhin, 1986 and O. gurvanensis Legalov, 2010 from Mongolia by the long metaventrite from the former species, and by the short rostrum from the latter.     

Mongolocypris kohi sp. nov.: A new Early Cretaceous non-marine ostracod species from the Jinju Formation,South Korea

A new non-marine ostracod Mongolocypris kohi sp. nov. is described from the upper Lower Cretaceous Jinju Formation of the Gyeongsang Basin, South Korea. This new species was described as Cypridea (Pseudocypridina) spp. by previous authors, but the typical rostrum shape, inconspicuous alveolar notch, the lack of alveolar ridge and the elongate limen are features that this species has in common with the genus Mongolocypris Szczechura, 1978. M. kohi sp. nov. is characterized by a reduced rostrum, the presence of a faint alveolar furrow and a slightly curved limen. This new species is considered an ‘early form’ of the genus Mongolocypris by its reduced rostrum and the faint alveolar furrow.     

Early Barremian orbitolinid record from the Moghan area,NW Iran: Northern margin of the Neotethys

Orbitolinid foraminifers are reported for the first time from lower Barremian shallow marine carbonate deposits of the Moghan area, NW Iran. According to geologic map of the Razi, these rocks were previously assigned to general age of the Early Cretaceous. The early Barremian age is documented based on stratigraphic range of the marker Valserina turbinata (Foury). Other orbitolinids such as Eopalorbitolina charollaisi Schroeder, Eopalorbitolina pertenuis (Foury), Paleodictyoconus cf. cuvillieri (Foury), Montseciella cf. alguerensis Cherchi and Schroeder, Paracoskinolina cf. maynci (Chevalier), Orbitolinopsis cf. buccifer Arnaud-Vanneau and Thieuloy, and Dictyoconus? pachymarginalis Schroeder also coexist. Obtained biostratigraphic data suggest that the range of Dictyoconus? pachymarginalis, hitherto known from the Aptian, has to be extended into the early Barremian. Most of the orbitolinid taxa are well known in Europe as northern Tethyan margin endemic forms. Therefore, the study area can be considered as part of the northern Tethys margin during the Barremian. This study also extends the palaeobiogeographic distribution of northern Tethyan orbitolinids eastwards as far as northwest Iran.     

Ammonites (Phylloceratina,Lytoceratina and Ancyloceratina) and organic-walled dinoflagellate cysts from the Late Barremian in Boljetin,eastern Serbia

Late Barremian ammonite fauna from the epipelagic marlstone and marly limestone interbeds of Boljetin Hill (Boljetinsko Brdo) of Danubic Unit (eastern Serbia) is described. The ammonite fauna includes representatives of three suborders (Phylloceratina, Lytoceratina and Ancyloceratina), specifically Hypophylloceras danubiense n. sp., Lepeniceras lepense Rabrenović, Holcophylloceras avrami n. sp., Phyllopachyceras baborense (Coquand), Phyllopachyceras petkovici n. sp., Phyllopachyceras eichwaldi eichwaldi (Karakash), Phyllopachyceras ectocostatum Drushchits, Protetragonites crebrisulcatus (Uhlig), Macroscaphites perforatus Avram, Acantholytoceras cf. subcirculare (Avram), Dissimilites cf. trinodosus (d'Orbigny) and Argvethites? sp. The taxonomic composition and percent abundance of the identified ammonites indicate that their taxa are predominantly confined to the Tethyan realm. Ammonites with smooth and slightly sculptured shells predominate among the studied fauna. The ammonite-bearing succession from Boljetin represents the lower part of the Upper Barremian, ranging in ammonite zonation from the Toxancyloceras vandenheckei Zone to the lower part of the Imerites giraudi Zone. The associated organic-walled dinoflagellate cysts confirm the Late Barremian age of the ammonite-bearing levels.     

A new Late Cretaceous crocodyliform from the western margin of Gondwana (La Rioja Province,Argentina)

The Cretaceous witnessed the greatest diversity of Gondwanan notosuchian crocodyliforms, which displayed high levels of diversity and a notable array of specialized forms that developed in different ecological niches. Among this diversity, the advanced notosuchians are a clade of mid body sized forms which displays a remarkable abundance but is restricted to two lithological units from the Late Cretaceous of South America, the Adamantina Formation in southeastern Brazil and the Bajo de la Carpa Formation in Patagonia (Argentina). The only exceptions known so far were the Late Cretaceous Labidiosuchus from the Marilia Formation in Brazil and Yacarerani from the Cajones Formation in Bolivia. Herein we report a new Cretaceous crocodyliform, Llanosuchus tamaensis gen. nov. et sp. nov., found in the Los Llanos Formation (Campanian?) in northwestern Argentina (La Rioja Province). The small specimen includes well preserved fragments of the cranium and mandible with an estimated skull size of about 9 cm lengths. This crocodyliform shares several derived characters with Notosuchus terrestris from the Bajo de la Carpa Formation (Patagonia) and it was found in a weakly developed sandy paleosol profile formed in wet local conditions but in a region characterized by semi-arid climate and active eolian sedimentation. The presence of a new advanced notosuchian in the Cretaceous of western Gondwana, and its intermediate geographical region between the known South American species (Brazil, Argentina and Bolivia), has interesting implications, and adds another record of an advanced notosuchian in deposits with inferred warm climates and semi-arid paleoenvironments. Finally, Llanosuchus tamaensis supports a Late Cretaceous age for Los Llanos Formation with important geological implications for La Rioja Province.     

Torremiroella hispanica Brun and Canérot, 1979 (benthic foraminifera) from the Lower Cretaceous of Central Iran and its palaeo-biogeographic significance

The larger benthic foraminifer Torremiroella hispanica Brun and Canérot, 1979, so far only known from its type-locality in southern Spain, is described from the Late Barremian–Early Aptian of Central Iran (Ardakan and Yazd areas). It is reported from foraminiferan pack- to grainstones associated with Balkhania balkhanica Mamontova, 1966, dated as early Aptian (Bedoulian). A review of the literature data suggests that both are typical northern Tethyan faunal components as indicated also by the assemblages of orbitolinid foraminifers and dasycladalean algae.     

A remarkable new genus of basal snakeflies (Insecta: Raphidioptera: Priscaenigmatomorpha) from the Early Cretaceous of China

Chrysoraphidia relicta gen. et sp. nov. is described from the Early Cretaceous (Barremian) of the Yixian Formation, Liaoning Province, China. Its venation is characterized by a mixture of character states that occur mainly in the Neuroptera and Raphidioptera. The assignment of Chrysoraphidia gen. nov. to Raphidioptera is supported by the presence of its distinct pterostigma and the configuration of the wing vein ‘subcosta anterior’. It is interpreted as the first record of a group of basal snakeflies (Priscaenigmatomorpha) from the Cretaceous of Asia, hitherto known only from the Early Jurassic of Europe.