Sporo-Pollen Assemblages from Late Phase of Early Cretaceous in Minhe Basin

Plenty of sporo-pollen fossils were found from the Upper Subformation of Hekou Formation at Chaijiatai, Lanzhou of Gansu, Minhe Basin. The sporo-pollen assemblage of the upper stratum of the Upper Suhformation was named as Schizaeoisporites-Cicatricosisporites. It could be further divided into two subassemblages. The upper one was Classopollis-Schiza- eoisporites, and the lower one was Piceapollenites-Cicatricosisporites. By analysing the periods of the important species and genera in the assemblage and comparing with the known assemblages in various districts, the author cosidered that the geologic age of the assemblage was the late phase of Early Cretaceous (Aptian-Alhian). The age of the second subassemblage was later which was Albian. So far, the stratum where the sporo-pollen fossils assemblage were found was the uppermost one of the Lower Cretaceous that have been found in Minhe Basin.     

Early Cretaceous Angiosperms of the Yanji Basin,Jilin Province

An assemblage of fossil plants was discovered in the Yanji Basin, Jitin Province, consisting mainly of pterid0Phytes, gymnosperms and a few angiosperms. The present paper deals with the angiosperms only; They are: Rogersia angunifolia, Saliciphyllum longifoliurn, Sapindopsis magnifolia, Sterculophyllurn eleganurn, ,Ficophyllum, "Sassafras", Ranunculophyllum pinnatisectum sp. nov., Clernatites lanceolatus sp. nov., and the fruits Carpolithus brookensis, Carpolithus sp. gymnosperm Sequoia as well, all angiosperms having the morphological features of early angiosperms. Most of them are similar to the elements of the Potomac Group in North America and to some extent approach the fossil plants of Neocomian in Mongolia. This assemblage is manifestly different from the Albian flora of Kolyma River (URSS) and Portugal of Europe because of belonging to different stages. Thus, the age of the Dalazi Formation of Yanji Basin is tentatively ascribed to Aptian. The characteristics of this assemblage indicate that the floras of Eurasia and North America had been closely related during the early Mid-Cretaceous and that the early angiosperms were widely distributed in the North Hemisphere. Judging from the characteristics of this assemblage and the deposition, the authors speculate that in Northeast China the climate was warm and humid during the early Mid-Cretaceous.     

New hybodont shark assemblage from the Early Cretaceous of the Basque-Cantabrian Basin

Hybodont remains from the Early Cretaceous of the Basque-Cantabrian Basin (Cantabric Range) in the North of Spain are described for the first time. This assemblage represents a highly diversified shark fauna adapted to different feeding habits. Isolated remains of six hybodont genera, namely Hybodus, Egertonodus, Planohybodus, Lonchidion, Parvodus, and Lissodus, have been recovered and described from the freshwater Vega de Pas Formation in the locality of Vega de Pas (Cantabria, Northern Spain). Most of these taxa are known from the English Wealden, making the shark fauna of the Vega de Pas 1 site the most similar assemblage to English Wealden shark fauna among any other site known in Europe.     

Falkland Islands biogeography: converging trajectories in the South Atlantic Ocean

Aim This paper describes the biogeographical setting of the Falkland Islands, in the context of the relationships of the islands’ biota to other sub‐Antarctic/cold temperate lands. Location The analysis focuses primarily on the Falklands biota, and explores its relationships to those of Patagonian South America and South Africa, other southern lands and the islands of the sub‐Antarctic Pacific, Indian and Atlantic Oceans. Methods The study derives largely from literature sources on the biota and geological history of the Falkland Islands. Results The animals and plants known from the Falkland Islands exhibit strong affinities with those of Patagonian South America, and especially Tierra del Fuego; additional affinities are with various remote islands of the sub‐Antarctic, as well as New Zealand and to a lesser extent Australia; often these are shared with Patagonia. While the biotic affinities might be interpreted, by some, as indicating a former Gondwanan/South American geological connection of the Falklands, geological evidence points to the Falklands formerly having a land connection to south‐eastern South Africa. Only faint hints of a South African biotic connection remain. The historical biotic and geological connections of the Falklands thus conflict. Moreover, the Falklands biota is so strongly Patagonian that derivation of that biota is best seen as resulting from dispersal, much of it probably recent. This dispersal biota appears to have replaced, and perhaps displaced, the South African biota present on the islands as they detached from South Africa and drifted across the south Atlantic Ocean, as it opened up as South America and Africa drifted apart.     

Palaeoecological preferences and geographical distribution of Late Maastrichtian deep-sea ostracods in the South Atlantic

The distributional patterns of deep-sea ostracods in the terminal Cretaceous South Atlantic were examined from seven DSDP/ODP holes (356, 525A, 527, 528, 529, 698A and 689B). Many of the genera recorded in this study are previously known from Campanian-Maastrichtian deep-sea sediments. However, the recovery of Aversovalva, Hemiparacytheridea, Profundobythere, Mayburya and Legitimocythere reveals considerable similarities with the Tertiary deep-sea ostracod fauna of the Pacific and the North Atlantic. The underlying causes controlling the variation in faunal density among the various sites are likely to be related to variation in food supply and, to a lesser extent, to variation in oxygen levels, since all sites quantitatively assessed are regarded to represent oligotrophic, well-oxygenated conditions. A Q -mode principal component analysis with varimax rotation yielded a first component largely dominated by Bythocypris and significantly correlated with palaeotemperature; there is an increasing abundance of Bythocypris towards higher latitudes with a maximum abundance at Site 689 where the palaeotemperature was around 9°C. A species of the thermophilic genus Cytherelloidea occurs also at this site, probably as a result of a slow adjustment to colder conditions in the absence of a thermocline at that time. The second component is largely dominated by Krithe and significantly correlated with palaeotemperature and palaeodepth. Among the sites studied, Krithe is most common at Site 356, where the palaeotemperature was around 15°C; today, most representatives of this genus are psychrospheric and adapted to temperatures below 10°C.     

Ostracoda and palaeo-oxygen levels, with particular reference to the Upper Cretaceous of East Anglia

It has been shown that the percentage of Platycopina (the sole remaining group of filter-feeding Ostracoda since the global extinction of the Metacopina in the Lower Toarcian) making up a fossil ostracod fauna can be used as a measure of dissolved oxygen in past oceans. High levels of platycopids indicate low oxygen and vice versa. A new scale is introduced here, based mainly on the environmental oxygen levels of modern oceans and their equivalent percentages of living platycopids, in order to evaluate the palaeo-oxygen levels of the Upper Chalk in East Anglia. The effects of varying oxygen concentrations on the overall simple species diversity of the Ostracoda is also shown to have important palaeoenvironmental implications. The study is based on 79 samples from the Santonian to Lower Maastrichtian of the Trunch Borehole and 126 samples from outcrops in Suffolk and Norfolk, ranging from the Coniacian to Lower Maastrichtian. The Coniacian is shown to have been a time of low to very low oxygen, except for its upper part that was much better ventilated. The Santonian and Lower Campanian were low to very low in their dissolved oxygen, while the Upper Campanian and particularly the Lower Maastrichtian had much higher oxygen levels. Notwithstanding these general trends, oxygen levels appear to have fluctuated rapidly throughout the interval, during times of both generally low and high oxygenation. These variations in oxygenation are thought to have been associated with the Oxygen Minimum Zone and its migrations onto the continental shelf and subsequent retreat to the continental slope. This in turn is related to sea-level fluctuations and this, together with the potential for the application of this technique to sequence stratigraphy are discussed.     

Serpulids and other calcareous tube-dwelling encrusting polychaetes from the Early Cretaceous Agrio Formation (Neuquén Basin,Argentina)

Serpulids and other related tube-dwelling polychaetes are often ignored when found as fossil remains. They are, however, a widespread and important group today, and abundant literature has been published on them. Knowledge of fossil serpulids is centered on European material, and little has already been done on South American fossil calcareous tubes. In this paper, seven serpulid and sabellid morphotypes are described from the Early Cretaceous marine Agrio Formation of Argentina, revealing a diversity of worms recorded as encrusters on bivalves, ammonites and corals. Sabellids are represented by Glomerula cf. serpentina. Serpulids are represented by two subfamilies: “Serpulinae” includes Mucroserpula mucroserpula, Parsimonia antiquata, Placostegus cf. conchophilus, Propomatoceros semicostatus and P. sulcicarinatus; Spirorbinae is represented by heavily worn tiny coiled tubes assigned to ?Neomicrorbis. Serpulids and sabellids are one of the main components of the mollusk-encrusting fauna recorded in the Agrio Formation, along with small oysters but much more diverse. They are most commonly found as post-mortem encrusters, but some cases of unquestionable living interaction are also found, such as serpulid tubes embedded on coral branches. They are often overgrown by bryozoans, and sometimes by oysters; they frequently occur aggregated.     

Age and implications of the Forest Bed, Falkland Islands, southwest Atlantic Ocean: Evidence from fossil pollen and spores

Diverse pollen and spore assemblages (microfloras) are preserved in organic clays and lignites associated with fossil tree remains in the Forest Bed. At present, these microfloras provide the only reliable basis for determining the age, composition, structure and affinity of the Forest Bed community. The Bed is suggested to be Middle? Miocene to Early Pliocene (age range Oligocene–Early Pliocene) based on the time distribution of a number of rare pollen types and the present-day ecology of their nearest living relatives in central–southern America and the southwest Pacific. The wet forest community whose remains form the Forest Bed was a form of broadleaf-gymnosperm temperate rainforest in which Dacrydium, Lagarostrobos and Podocarpus are likely to have formed an overstorey above a closed canopy dominated by Nothofagus (Nothofagus) spp. The latter subgenus is now endemic to ±uniformly wet regions in southern South America whilst two of the tall gymnosperms (Dacrydium, Lagarostrobos) are now endemic to the southwest Pacific region. An extinct, probable shrub-sized, conifer (Podosporites microsaccatus) appears to have formed the ground cover. Ferns and fern allies were very rare, in contrast to most living Nothofagus-gymnosperm communities. Fossil pollen and spore types produced by uncommon subcanopy tree, shrub and fern species potentially provide a means for more accurately dating the deposit once their time of first occurrence and extinction at subantarctic latitudes in the southwest Atlantic region is established (nearest living equivalents given in parentheses) — Clavatipollenites cf glarius (Hedyosmum), Thymelaepollis sp. (Ovidia-type) and Cyatheacidites annulatus (Lophosoria). This will require palynostratigraphic analysis of Late Palaeogene–Neogene sediments recovered from basins surrounding the Falkland Islands, for example from DSDP Site 329 drilled on the Maurice Ewing Bank at the eastern margin of the Falkland Plateau.     

甘肃早白垩世恐龙蛋化石新类型（英文）

甘肃省早白垩世地层中,出土了大量恐龙骨骼以及恐龙足迹化石,但是至今未有蛋化石的报道。根据发现于兰州-民和盆地下白垩统河口组的蛋壳化石,建立一恐龙蛋新蛋属、蛋种,并将其归于一新蛋科:Polyclonoolithidae(多小枝蛋科)。新发现的蛋化石标本不同于所有已知的恐龙蛋类型,具有独特的显微特征组合:分叉的蛋壳单元向外延伸至蛋壳外表面,并未在靠近蛋壳外表面处融合成层;弦切面上具相互链接或独立的多角形的蛋壳单元;以及不规则的气孔道。中国的恐龙蛋化石大多出自晚白垩世地层,仅在辽宁有早白垩世恐龙蛋的报道。新发现扩展了中国恐龙蛋化石的地质和地理分布,也有可能为圆形蛋科蛋壳结构的起源提供新的认识。     

Origin of peloids in Early Cretaceous deposits, Dorset, South England

Peloids are ubiquitous components in modern and fossil carbonates. The term peloid is non-genetic because the origin of these grains and the pathways of their formation are not fully understood. Based on Berriasian material originating from Dorset, southern England, we report here on peloids that result from the more or less in-place breakdown of previously micritized bivalve shells. The continuum from shell breakdown to peloids is documented by petrography and observation by scanning electron microscopy. The identical elemental composition of peloids and micritized shells confirms the petrographic observation and interpretation. Bivalve shells that were previously entirely micritized appear to be the preferential source for the formation of peloids. Obviously, the micritization weakened the shells, facilitating their breakdown and abrasion. This result identifies the fragmentation of micritized shells as a process leading to the formation of distinct peloids, adding to the categories of peloids recognized to date. Mold, mud, and microbial peloids observed in the studied sections and documented herein are distinct from peloids derived from bivalve shells.     

A new scincomorph lizard from the Early Cretaceous of Puebla, Mexico

A complete skeleton of a new scincomorph lizard from the Early Cretaceous deposits of Tepexi de Rodriguez is described. Tepexisaurus tepexii gen. et sp. nov. is the best preserved early scincomorph and the first known taxon that is morphologically primitive to scincoids and paramacellodid lizards. The presence of pointed ventral parietal downgrowths, the coronoid overlapped anteriorly and posteriorly by the dentary and surangular, a small medial flange on the retroarticular process, and weak zygosphene and zygantrum articulations suggest scincoid relationships, but the absence of ventral and dorsal osteoscutes place Tepexisaurus as sister-group of this taxon. It shares the presence of + 30 closely packed teeth with the poorly known Upper Jurassic genus Saurillus and Pseudosaurillus , but differences in the coronoid structure, Meckelian groove and jaw proportions indicate that both taxa are distinct. Similar to Tepexisaurus , the absence of osteoscutes in Saurillus, Pseudosaurillus and Saurillodon place these taxa in a more primitive position relative to other paramacellodids which should be included within Scincoidea. Thus, Paramacellodidae as previously defined is a paraphyletic assemblage. The late presence of a pre-scincoid lizard in the Albian deposits of Tlayua can be correlated with the presence of sphenodontians and the relictual nature of the basal squamate Huehuecuetzpalli mixtecus. It gives additional evidence to support the hypothesis that Tlayua was a refuge for terrestrial archaic forms during the Albian.     

A taxonomic reevaluation of freshwater ostracods (Crustacea,Ostracoda) referred to the genus Cypridopsis Brady, 1868 from Southeast Asia

A taxonomic reevaluation of five species of Southeast Asian freshwater ostracods formerly assigned to the genus Cypridopsis Brady, 1868 has resulted in the retention of Cypridopsis adusta Sars, 1903, Cypridopsis exigua Sars, 1903 and Cypridopsis dubia Sars, 1903 in Cypridopsis and transfer of Cypridopsis albida (Vavra) 1898 and Cypridopsis arsenia Tressler, 1937 to the genus Plesiocypridopsis Rome, 1965.     

Neoselachians (Chondrichthyes,Elasmobranchii) from the Lower and lower Upper Cretaceous of north‐eastern Spain

Extensive sampling of several Barremian and Albian–Cenomanian levels across the Aguilón, Oliete and Aliaga subbasins of the Iberian Basin, north‐east Spain, yielded abundant material of new or so far poorly known neoselachians. The faunas consist of 16 different species, five of which represent new species and two new genera: Cantioscyllium brachyplicatum sp. nov. , Platypterix venustulus gen. et sp. nov. , Ptychotrygon pustulata sp. nov. , Ptychotrygon striata sp. nov. and Iberotrygon plagiolophus gen. et sp. nov. In addition, teeth of Heterodontus cf. H. carerens, Lamniformes indet., Pteroscyllium sp., Scyliorhinidae indet., Rhinobatos sp., Spathobatis sp., Belemnobatis sp., Ptychotrygon geyeri, Ptychotrygon sp. and Celtipristis herreroi are described. The new family Ptychotrygonidae is defined. The localities comprise palaeoenvironments ranging from lacustrine and shallow lake to open marine settings. Neoselachians are almost completely absent from continental settings in the Barremian, as a result of prevailing freshwater conditions, but became more abundant in marine strata. The Albian–Cenomanian selachian assemblage is the most profuse and diverse of the three assemblages studied. It is dominated by small, benthic and near‐coastal taxa, for instance Cantioscyllium and Ptychotrygon, and contains several new species, including an endemic batoid, Iberotrygon plagiolophus gen. et sp. nov. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 155 , 316–347.     

A new oospecies of Similifaveoloolithidae from the Xiuning Basin,Late Cretaceous of Anhui,China

Well-preserved dinosaur eggs from the Cretaceous Huizhou Formation in the Xiuning Basin, Anhui Province, China, are analysed in this paper. We describe a new oospecies, Similifaveoloolithus qiyunshanensis, based on several distinct characters of external morphology, size, eggshell thickness, and internal microstructure. Radial sections of this new oospecies show branched eggshell units with a fused layer near the outer surface, while numerous irregular pores and cones constitute a honeycomb pattern in tangential sections. The discovery of S. qiyunshanensis expands the distribution of Similifaveoloolithidae dinosaur eggs in China and provides new fossils for researching dinosaur eggshell formation mechanisms which are different from those of the currently known oofamilies. The dinosaur-egg-bearing strata in the Huizhou Formation have been dated to the early Late Cretaceous (Cenomanian-Turonian) on the basis of a similar dinosaur egg assemblage in the Tiantai Basin in Zhejiang Province. The eggs described in this paper are thought to have been laid in a buried nest while enrichment of trace elements in eggshells may have been caused by their ingestion into the body of the dinosaur producer. We suggest that the paleoclimate of this habitat was semi-arid to arid and that this environment was favourable for the preservation of eggs.http://zoobank.org/LSIDurn:lsid:zoobank.org:pub:9D63A51F-5A4B-4249-901D-42A33E9FA933     

Cretaceous and Cenozoic non-marine deposits of the Northern South Yellow Sea Basin, offshore western Korea: palynostratigraphy and palaeoenvironments

Palynological analyses of two wells (Haema-1 and Kachi-1) located in two sub-basins of the Northern South Yellow Sea Basin have been carried out in order to establish a palynostratigraphic breakdown of the sedimentary succession and to determine environments of deposition. Seven assemblage zones and two assemblage subzones have been erected on the basis of frequency variations in, and occurrences of, biostratigraphically significant palynomorphs as follows: Classopollis-Ephedripites Assemblage Zone (AZ): Barremian-Albian; Alisporites-Aquilapollenites-Penetetrapites AZ, which is subdivided into an Alisporites-Rugubivesiculites Assemblage Subzone: Cenomanian-Lower Maastrichtian, and an Aquilapollenites-Penetetrapites Assemblage Subzone: Upper Maastrichtian; Momipites-Coryluspollenites AZ: Paleocene; Caryapollenites-Inaperturopollenites AZ: Lower-Middle Eocene; Quercoidites-Pinuspollenites AZ: Upper Eocene; Liquidambarpollenites-Fupingopollenites-Magnastriatites AZ: Lower-Middle Miocene; Graminidites-Persicarioipollis AZ: Pliocene. The depositional environments represented by the well sections are considered to have been generally fluvio-lacustrine, and the climate to have varied between semi-arid and wet, and subtropical and warm temperate, except during the Late Eocene and Pliocene when a cool-temperate climate prevailed. Six stages in the development of the sub-basins are recognised. These are: (1) initial stage of rift or pull-apart basin-formation during the Late Jurassic?-Cretaceous; (2) subsidence from the Paleocene to Middle Eocene; (3) alternation of uplift and subsidence in the Late Eocene; (4) synrift inversion and erosion through the Oligocene; (5) uplift during the Early Miocene; and (6) widespread subsidence from the Middle Miocene onwards apart from during the Early Pliocene when the region was subjected to uplift once more.     

Two Angiosperm Reproductive Organs from the Early Cretaceous of China

Two fossil reproductive organs of early angiosperms were collected from the Yanji Basin, Jilin Province of China. The assemblage of fossil plants consist mainly of pteridophytes, gymnosperms and a few angiospoermms. The present paper only reports the two reproductive organs of angiosperms. They are Archimagnolia rostrato-stylosa gen.et sp. nov., Eucommioites orientalis sp.nov. The first is a slightly elongated floral axis(receptacle), with about 20 carpels helically arranged. The carpels are free from each other and attenuated into a beak-like structure at the apex, with the base inserted into the receptacle. A comparison with living plants indicated its close relationship with some members of the Magnoliaceae. The second is a samara, similar to a fruit of the genus Eucommia, narrow-oblong, 2-lobed at the apex with the lobes stigmatic on theinner side. The seed is situated at the middle of fruit, oblong in shape.     

The non-avian theropod track Jialingpus from the Cretaceous of the Ordos Basin,China, with a revision of the type material: Implications for ichnotaxonomy and trackmaker morphology

Deposits from the Ordos Basin of mid-western China are rich in body fossils and ichnofossils of Early Cretaceous vertebrates. Thousands of Early Cretaceous sauropod, theropod and bird tracks described since 1958 have been found at several localities in the basin. We report two new sites (Dijiaping and Bawangzhuang) in the Luohe Formation of the Ordos Basin, Shaanxi Province, which contain small theropod footprints that are here referred to the ichnogenus Jialingpus. The assignment is based on pad configurations including (1) the large metatarsophalangeal area positioned in line with the axis of digit III, (2) the subdivision of this part into a small pad behind digit II, which in some specimens is close to the general position of the hallux (digit I), and a large metatarsophalangeal pad behind digit IV, and (3) a distinct inter-pad space between metatarsophalangeal pads and proximal phalangeal pads of digits II and III. We re-describe the type material of the type ichnospecies Jialingpus yuechiensis from the Upper Jurassic Penglaizhen Formation of Sichuan Province, proposing a largely amended diagnosis for this ichnotaxon. The presence of a digit I trace in the holotype, indicating a relatively long hallux, and the large metatarsophalangeal area positioned in line with digit III distinguishes Jialingpus from the ichnogenus Grallator and similar tracks that all lack these features. The only difference between Jialingpus specimens from the Cretaceous of the Ordos Basin and those of the Jurassic Penglaizhen Formation is the larger digit divarication in the Cretaceous taxon. This is the fourth record of Jialingpus in China and the second in Cretaceous strata, with the first being those from the Huangyangquan locality in Xinjiang, China.     

New Trigonioidoidea (Bivalvia; Unionoida) from the Early Cretaceous of Spain

Abstract: Two taxa belonging to the Trigonioidoidea (Order Unionoida) are described from the Early Cretaceous of Spain. Nippononaia (Paranippononaia) camerana subgen. et sp. nov. is described from the Aptian of the Cameros Basin of the north‐west Iberian Range. Subnippononaia fordi Barker et al., 1997 is described from new material from the Calizas de la Huérguina Formation (Late Barremian) from Las Hoyas and Buenache de la Sierra, Cuenca Province, and Subnippononaia is raised to generic status. The stratigraphy and palaeoenvironment of the Cornago G exposure of the Enciso Group where Nippononaia (Paranippononaia) camerana originates is interpreted as a fresh to brackish water system.     

Taphonomy and palaeoecology of plant remains from the oldest African Early Cretaceous amber locality

The first Mesozoic amber for Africa was recently reported from the Middle-Upper Valanginian of the Kirkwood Formation (Algoa Basin, Republic of South Africa). A palaeobotanical and taphonomical study is performed here on the amber-bearing strata. Palaeobotanical remains indicate a warm to hot, semi-arid climate. Taphonomic analysis of the plant debris shows that the assemblage is allochthonous and was the result of transport by high energy flooding events and subsequent deposition in crevasse splay or over bank deposit. However, the plant fragmentation was probably previously initiated in the leaf litter, whose decay was probably slowed down by a combination of biological and climatic factors. The different oxidation degrees of amber also support a certain residence time in contact with the atmosphere and possible reworking.