Early Cenomanian Research Articles

Early cretaceous topographic growth of the Lhasaplano, Tibetan plateau: Constraints from the Damxung conglomerate

AbstractConstraining the timing of early topographic growth on the Tibetan plateau is critical for any models of India‐Asia collision, Himalayan orogeny and subsequent plateau development in the Cenozoic. Stratigraphic, sedimentological and provenance analysis of the Lower Cretaceous red‐beds of the Damxung Conglomerate provide new key information to reconstruct the paleogeography and the tectonic evolution of the Lhasa terrane at the time. The over 700‐m‐thick Damxung Conglomerate documents distal alluvial fan to braidplain sedimentation passing upward to proximal alluvial fan sedimentation. Deposition began near sea level, as documented by limestone beds occurring at the base of the unit. Zircon U–Pb dating of interbedded tuff layers constrain deposition age at ca. 111 Ma. Abundance of volcanic clasts, Cretaceous U–Pb ages and Hf isotopes of detrital zircons yielding mainly negative εHf(t) values together with paleocurrent data indicate an active volcanic source located in the North Lhasa subterrane. Pre‐Mesozoic‐aged zircon, recycled quartz and (meta) sedimentary rock fragments increase up‐section, indicating progressive erosional exhumation of the Paleozoic sedimentary/metasedimentary basement. The Damxung Conglomerate thus records a significant uplift and unroofing stage in the source region, implying initial topographic growth on the Lhasa terrane at early Albian time. Early Cretaceous topographic growth on the Lhasa terrane is supported by the stratigraphic record in the Linzhou basin, the Xigaze forearc basin and the southern Nima basin. In contrast, marine strata in the central‐western Lhasa terrane lasted until the early Cenomanian (ca. 96 Ma), indicating diachronous marine regression on the Lhasa terrane from east to west.

A new subfamily of Feaellidae (Arachnida, Chelonethi, Feaelloidea) from Southeast Asia.

The first extant representatives of the pseudoscorpion family Feaellidae from Southeast Asia are described. Cybella n. gen. is proposed for Cybella deharvengi n. sp. (type species), collected from an isolated limestone hill in Hon Chong Province, Vietnam, and C. bedosae n. sp., found in a limestone cave in Kampuchea, Cambodia. Cybella species seem to be restricted to karst formations and are probably troglophilic. The type localities of the two known species are threatened by quarrying activities, these being particularly pressing in the case of C. deharvengi n. sp. Cybella shows important differences from other Feaellidae that require a modification of the familial diagnosis and justify the erection of a new subfamily, Cybellinae. The discovery of this group provides insights into the evolution of the unusual morphology of the family, notably concerning the pleural plates of Feaellinae, which are lacking in Cybellinae. The smaller sclerites of the pleura of Pseudogarypidae and Feaellidae are shown to be muscle apodemes, which provide an additional synapomorphy for Feaelloidea. Two types of coxal spines, termed primary and secondary, are distinguished in Feaelloidea, based on the presence of a lumen within the primary spines and its absence in secondary spines. The new morphological term atrial plate is proposed for a sclerotized plate of the male genitalia, extending between the lateral rods and the lateral apodemes. Claims that the internal genital setae of males of non-chthonioid pseudoscorpions are secretory are reviewed and found to lack support. Additional information concerning the fossil genus Protofeaella Henderickx, 2016 is provided, based on an adult male in amber from the Cretaceous (lowermost Cenomanian) of Myanmar. Protofeaella shares with Cybella the absence of pleural plates and the antiaxial position of the chemosensory setae of the movable chelal finger. However, it differs from both Cybellinae and Feaellinae in having relatively long chelal fingers that lack a tuberculate basal tooth, both of which are interpreted as symplesiomorphic states within Feaellidae. Protofeaella is therefore provisionally treated as a stem-group feaellid and not assigned to a subfamily. The existence of a Cretaceous member of the Pseudogarypidae is noted in the mid-Cretaceous (late Albian‒early Cenomanian) of Germany, representing the oldest record of this family.

Cretaceous sedimentation in the outer Eastern Carpathians: Implications for the facies model reconstruction of the Moldavide Basin

The mid Cretaceous is characterized by high eustatic sea-levels with widespread oxic conditions that made possible the occurrence of globally correlated Oceanic Red Beds. However, very often, these eustatic signals have been overprinted by local tectonics, which in turn resulted in Lower Cretaceous closed and anoxic basins, as in the Eastern Carpathians. There, the black shale to red bed transition occurs in the latest Albian up to the early Cenomanian. Although earlier studies discussed the large-scale basin configuration, no detailed petrography and sedimentology study has been performed in the Eastern Carpathians. This paper describes the Hauterivian to Turonian lithofacies and interprets the depositional settings based on their sedimentological features. The studied sections crop out only in tectonic half windows of the Eastern Carpathians, part of the Vrancea Nappe. The lithofacies comprises black shales interbedded with siderites and sandstones, calcarenites, marls, radiolarites and red shales. The siliciclastic muddy lithofacies in general reflects accumulation by suspension settling of pelagites and hemipelagites in anoxic (black shale) to dysoxic (dark gray and gray to green shales) and oxic (red shales) conditions. The radiolarites alternate with siliceous shales and are considered as evidence of climate changes. The sandstones represent mostly low and high-density turbidite currents in deep-marine lobes, as well as channel/levee systems. The source area is an eastern one, e.g., the Eastern Carpathians Foreland, given the abundance of low grade metamorphic clasts. The Hauterivian – lower Albian sediments are interpreted as deep-marine, linear and multiple sourced mud dominated systems deposited in a mainly anoxic to dysoxic basin. The anoxic conditions existed in the early to late Albian, but sedimentation changed to a higher energy mud/sand-dominated submarine channels and levees. This coarsening upwards tendency is interpreted as the effect of the Aptian to Albian compressional tectonics of the Carpathians. The deepening of the Moldavide Basin from the Cenomanian is most probably linked to a significant sea-level rise.

New Prionoglarididae from Burmese amber (Psocodea: Trogiomorpha: Prionoglaridetae)

One new genus with three new species of the family Prionoglarididae, Palaeosiamoglaris leinhardi Azar, Huang et Nel gen. et sp. nov.; P. burmica Azar, Huang et Nel sp. nov. and P. inexpectata Azar, Huang et Nel sp. nov. are characterised, illustrated and described from Cretaceous Burmese amber. Palaeosiamoglaris gen. nov. share several characters with the recent genus Siamoglaris Lienhard, 2004, endemic to the Oriental (Sino-Indian) Region. A new tribe Siamoglaridini Azar, Huang et Nel trib. nov. is established to accommodate the group Siamoglaris + Palaeosiamoglaris; the other Prionoglaridinae being attributed to Prionoglaridini. This discovery implicates a palaeobiogeographic repartition for this particular tribe (Siamoglarini) that is still the same currently. Most diagnostic features show a nearly stasis state, supporting the notion that these characters appeared at least by the early Cenomanian. A checklist of all prionoglaridids is given.

Permineralización en restos de dinosaurios preservados en depósitos de desbordamiento de la Formación Bajo Barreal (Cretácico Superior), Patagonia central, Argentina.

The fossil deposit Cañadón Las Horquetas, placed in the centre-south of the Chubut Province, includes the Bajo Barreal Formation of early Cenomanian – late Turonian age. This site presents the greater abundance and diversity of fossil vertebrates in the San Jorge Gulf Basin. The diagenetic processes reported herein represent a little addressed subject in taphonomic studies involving dinosaurs. We present for the first time information on the permineralization processes that affected the dinosaur remains preserved in overflow deposits from the Bajo Barreal Formation, as well as new sedimentological data of the studied unit.Samples from three specimens were studied by chemical analysis, polarization petrographic microscope, X-ray diffraction and scanning electron microscopy (SEM). These studies show that all the dinosaurs have had a similar diagenetic history, with the same pattern of mineral replacement. Besides, the similar chemical composition found in the fossils and in the bearing rocks suggest that the enrichment with new elements found in the studied dinosaur remains was due to the direct exchange with the sediments in which they were buried. The now reported diagenetic conditions can be preliminarily extended to the whole lower member of the Bajo Barreal Formation.

Reservoir origin and characterization of gas pools in intrusive rocks of the Yingcheng Formation, Songliao Basin, NE China

In 2013, the first discovery of gas pools in well LS 208 in intrusive rocks of the Songliao Basin (SB), NE China was made in the 2nd member of the Yingcheng Formation in the Yingtai rift depression, proving that intrusive rocks of the SB have the potential for gas exploration. However, the mechanisms behind the origin of reservoirs in intrusive rocks need to be identified for effective gas exploration. The gas pool in intrusive rocks can be characterized as a low-abundance, high-temperature, normal-pressure, methane-rich, and lithologic pool based on integrated coring, logging, seismic, and oil test methods. The intrusive rocks show primary and secondary porosities, such as shrinkage fractures (SF), spongy pores (SP), secondary sieve pores (SSP), and tectonic fractures (TF). The reservoir is of the fracture–pore type with low porosity and permeability. A capillary pressure curve for mercury intrusion indicates small pore-throat size, negative skewness, medium–high displacement pressure, and middle–low mercury saturation. The development of fractures was found to be related to the quenching effects of emplacement and tectonic inversion during the middle–late Campanian. SP and SSP formed during two phases. The first phase occurred during emplacement of the intrusive rock in the late Albian, when the intrusions underwent alteration by organic acids. The second phase occurred between the early Cenomanian and middle Campanian, when the intrusions underwent alteration by carbonic acid. The SF formed prior to oil charging, the SSP + SP formed during oil charging, and the TF formed during the middle–late Campanian and promoted the distribution of gas pools throughout the reservoir. The intrusive rocks in the SB and the adjacent basins were emplaced in the mudstone and coal units, and have great potential for gas exploration.

Mid-Cretaceous dinosaur track assemblage from the Tongfosi Formation of China: Comparison with the track assemblage of South Korea

A Yanji Basin tracksite in the Cretaceous Tongfosi Formation in the Yanbian Korean Autonomous Prefecture, Jilin Province was reinvestigated twenty years after the original study.The re-examination confirms the presence of tracks tentatively referred to ornithopods and theropod tracks including several not previously reported. In addition to the main track-bearing level, a second footprint horizon was identified from which a probable ornithopod track was collected. Some of the formerly identified tracks were documented using photogrammetry, whereas others that had been collected, eroded, buried or obscured by dense vegetation. The age of the track-bearing beds is inferred to be late Albian to early Cenomanian. Comparison with track-bearing units of the same age in Shandong, China, and Korea indicated quite different compositions of track assemblages. In the case of the Korean sites the differences may be facies related. While the Korean ichnofauna is characterized by the co-occurrence of ornithopod, sauropod and tridactyl theropod tracks with didactyl dromaeosaurid, Minisauripus (small theropod), pterosaur and avian tracks, the latter four are absent in the Tongfosi assemblage. This could reflect a restricted environment being not favourable for activities of these trackmakers or simply a preservational bias.

New Evanioid Wasps from the Cenomanian of Myanmar (Hymenoptera: Othniodellithidae, Aulacidae), with a Summary of Family-Group Names Among Evanioidea

ABSTRACT Three new evanioid wasps (Euhymenoptera: Evanioidea) are described and figured from individuals preserved in mid-Cretaceous (earliest Cenomanian) amber from northern Myanmar. The new species represent the families Othniodellithidae and Aulacidae, both previously recorded from Burmese amber. Xenodellitha preta, new genus and species, is the second othniodellithid wasp and the diagnosis of the family is slightly emended in order to accommodate this species. The subfamily Hyptiogastritinae (Aulacidae) is expanded to include Protofoenus Cockerell and a third genus from Burmese amber. Archeofoenus tartaricus, new genus and species, is the third known species of the extinct aulacid subfamily Hyptiogastritinae, differing from Hyptiogastrites electrinus Cockerell in the low position of the discal cell and the open subdiscal cell in the forewing, and from Protofoenus swinhoei Cockerell in the form of the head and mandible, coloration, and forewing venational details. Together, Archeofoenus and Protofoenus...

Mesomegaloprepidae, a remarkable new damselfly family (Odonata: Zygoptera) from mid-Cretaceous Burmese amber

Mesomegaloprepus magnificus gen. et sp. nov. (Odonata: Zygoptera) is described from more than 14 specimens in eight pieces of mid-Cretaceous (earliest Cenomanian, ca. 99 Ma) amber from Myanmar. Possible phylogenetic affinities with the Neotropical Latibasaliidae, Thaumatoneuridae, and Pseudostigmatinae are discussed, and a relationship with Pseudostigmatinae considered as possible, but because of conflicting evidence separate family status as Mesomegaloprepidae fam. nov. is tentatively preferred. The remarkable degree of homoplastic conflict in the wing venational similarities indicates that these represent relatively weak evidence for phylogenetic relationships. The palaeoecology, including sexual dimorphism in wing colouration, of the new taxon is discussed, and the large number of inclusions explained with possible breeding behaviour in association with water-filled tree holes (phytotelmata) of the amber tree, similar to extant Pseudostigmatinae. The position of all alleged fossil Thaumatoneuridae are discussed and revised: Eothaumatoneura ptychoptera Pongracz, 1935 from the Eocene Geiseltal locality is restored in Thaumatoneuridae. Cretaceous Euarchistigma and Paleogene Eodysagrion are tentatively retained as subfamilies Euarchistigmatinae and Eodysagrioninae in Thaumatoneuridae. Paleogene Dysagrioninae and Petrolestinae are removed from Thaumatoneuridae and attributed to a restored family Dysagrionidae, and Paleocene Latibasaliidae is transferred from Amphipterygoidea to Epallagoidea.

The Albian–Cenomanian transition and Oceanic Anoxic Event 1d – an example from the Boreal Realm

AbstractThe upper Albian to lower Cenomanian interval in the Hanover area (Germany) is characterized by a well‐developed lithological transition from upper Albian monotonous (marly) claystones of several hundred metres thickness, which become enriched in biosilica in the topmost Albian, to increasingly CaCO3‐rich marls and limestones in the lower and middle Cenomanian. This study presents a new 165 m thick composite record spanning the latest Albian to mid‐early Cenomanian (ca 103·0 to 97·5 Ma) based on two core drillings at Anderten in the central Lower Saxony Basin (east of Hanover), which is a sub‐basin of the North German Basin. Due to the lack or delayed occurrences of Tethyan biostratigraphic markers for the late Albian and early Cenomanian in the Boreal Realm, the definition of the Albian–Cenomanian boundary, as based on the lowest occurrence of Thalmanninella globotruncanoides, is not applicable. In order to overcome this issue, an integrated biostratigraphic–chemostratigraphic approach has been employed. In addition to biostratigraphy (calcareous nannofossils, ostracods, planktonic foraminifera and inoceramids), the Anderten succession has been studied using sedimentary geochemistry (CaCO3, total organic carbon, δ13C and δ18O), γ‐ray logging and X‐ray fluorescence core scanning. This approach enabled successful correlation of the composite Anderten record to European reference sections in England, south‐east France and Italy, as well as to further low‐resolution records from the Lower Saxony Basin (Wunstorf and Konrad 101 core). This work has made it possible to identify the δ13Ccarb expression of: (i) the Oceanic Anoxic Event 1d; (ii) the Albian–Cenomanian boundary interval; and (iii) potentially the Lower Cenomanian Event(s). Chemostratigraphic age assignments are supported by biostratigraphic results. Calcareous nannofossils indicate an extended Upper Cretaceous 0 (UC0) zone (upper Albian) up to Upper Cretaceous 2 (UC2; upper lower Cenomanian), and the occurrence of the ostracod Physocythere steghausi supports an early Cenomanian age for most of the upper part of the composite record. Notably, influxes of the planktonic foraminifer Thalmanninella aff. reicheli have previously been described from this area and the first appearance of this taxon is usually used to define the base of the middle Cenomanian Substage. However, findings from the Anderten cores and elsewhere suggest that this taxon has an apparently earlier first appearance, questioning previous age assignments from the Boreal Realm solely based on planktonic foraminifera. Due to both moderately well‐preserved microfossils and high sedimentation rates, the drilled succession of Anderten is considered as a potential Boreal reference section for the Albian–Cenomanian transition.

Two new genera of Cretaceous dustywings in amber from northern Myanmar (Neuroptera: Coniopterygidae)

Two new genera and species are added to the fauna of dustywings (Coniopterygidae) preserved in Upper Cretaceous (earliest Cenomanian) amber of northern Myanmar, doubling the described diversity from this deposit. One genus is of the subfamily Aleuropteryginae and described as Achlyoconis heptatrichia Engel, new genus and species. This species is noteworthy for the infumate and patterned wings and unique presence of seven prominent setae positioned on thickenings occurring along the length of the forewing media. Paranimboa litotes Engel, new genus and species, is representative of the subfamily Coniopteryginae and distinctive among Mesozoic groups for the unbranched Rs, among other traits. In addition, a peculiar larva preserved alongside the holotype of P. litotes is described. While having a prothoracic and head form similar to aleuropterygines as well as a labial palpus with only two palpomeres, diagnostic for Coniopterygidae, the antenna bears four articles rather than the two present in crown-group dustywings. A revised key to the genera of Cretaceous Coniopterygidae is provided.

Evolutionary trends and biostratigraphical application of new Cenomanian alveolinoids (Foraminifera) from the Natih Formation of Oman

An exhaustive sampling of the Cenomanian deposits corresponding to the Natih Formation in the Oman Mountains has been carried out in several field trips. The larger foraminifera representatives of the superfamily Alveolinoidea Ehrenberg, 1839 found in the collected material have been studied in order to more precisely identify and constrain their stratigraphical distribution. The following new taxa are introduced: Decastroinae subfam. nov., Praealveolininae subfam. nov., Reichelia gen. nov., R. magna sp. nov., Decastoria serrakieli sp. nov., D. oblonga sp. nov., D. miaidinensis sp. nov., Praealveolina arabica sp. nov. and P. acuta sp. nov. Other simpler alveolinoids, such as Simplalveolina gr. simplex, have been found together with these forms. The alveolinoids have been found in four successive assemblages. Assemblage I contains Alveocella wernliana, Myriastyla omanensis, M. grelaudae and Cisalveolina nakharensis; assemblage II contains Decastroia serrakieli sp. nov. and Simplalveolina gr. simplex; assemblage III contains D. razini, D. oblonga sp. nov., Reichelia magna gen. et sp. nov., D. miaidinensis sp. nov. and Simplalveolina gr. simplex; and assemblage IV, which is only found in Wadi Mi'Aidin, contains abundant D. miaidinensis sp. nov., Praealveolina arabica sp. nov. and P. acuta sp. nov. The age attributed to assemblage I is lowermost Middle Cenomanian, the age of assemblages II and III is Middle Cenomanian, and assemblage IV is interpreted as Middle Cenomanian to early Late Cenomanian. From a phylogenetic point of view, alveolinoids diversified and evolved in two successive episodes: a lower maturation cycle, corresponding to assemblage I, and an upper cycle, corresponding to assemblages II to IV. Cenomanian alveolinoids are more abundant and diverse than was previously thought and it seems that they split and evolved in parallel lineages, probably from unknown simple alveolinoids of milioline origin.http://zoobank.org/urn:lsid:zoobank.org:pub:B7A96EE3-BEF7-49E9-A3E0-9FE6094FB0A2

Diverse Orthorrhaphan Flies (Insecta: Diptera: Brachycera) in Amber From the Cretaceous of Myanmar: Brachycera in Cretaceous Amber, Part VII

A remarkable diversity of new nonempidoid orthorrhaphan flies from the mid-Cretaceous of Myanmar (Late Albian–Early Cenomanian, ca. 99 Ma) is presented, including 28 species (all but one new) in 22 genera (13 new), and at least 12 families. Two families are new; three genera are unplaced in Tabanomorpha and one unplaced within Brachycera. Comparisons are presented between the amber taxa and extensive lithified taxa from the Jurassic and Cretaceous of eastern Laurasia.In Stratiomyomorpha: A new species of Zhangsolvidae has color patterns and body shape that apparently mimic Vespidae or other stinging aculeate wasps. Diverse new Xylomyidae and Stratiomyidae are described, the latter with male terminalia preserved in detail. In Tabanomorpha: The genus Athericites Mostovski et al. is synonymized with Palaepangonius Ren, and a new species of Galloatherix Nel is described in which the female proboscis is much longer than that of the male. All three genera were attributed to Athericidae, but the amber species reveal they are more basal tabanomorphs. Described are a new genus of stem-group Tabanoidea and a new species of Cratotabanus Martins-Neto and Kucero-Santos (Tabanidae), previously known from the Cretaceous of Brazil and New Jersey. In Nemestrinoidea: Three species of Hirmoneura Meigen are the first Nemestrinidae known from amber; one species has long cerci typical of Recent species of the genus. A new species of the Mesozoic family Rhagionemestriidae reveals this family is closely related to Acroceridae, not Xylophagidae as previously proposed. In Archisargoidea: A new species of Tethepomyiidae is described, the family known only in Cretaceous amber from New Jersey, Spain, and Myanmar. In Asiloidea: Three new species and genera of Bombyliidae are described, two of them with abdominal setal “baskets” distinctive to females of higher bombyliids. A fourth new asiloid genus is a probable stem-group bombyliid. The recently described Pseudorhagio Zhang et al., is transferred from Tabanomorpha to Bombyliidae. The male of a new species of Burmapsilocephala Gaimari and Mostovski (Apsilocephalidae) has terminalia very similar to that of Evocoa (Evocoidae: Recent, Chile), corroborating close relationship of the two families. In Families incertae sedis: A new species of Hilarimorphites Grimaldi and Cumming (Apystomyiidae) is described, the family known only in New Jersey and Burmese amber and the Recent fauna of California, and a sister group to either Cyclorrhapha or Eremoneura. Mysteromyiidae and Eucaudomyiidae, new families, are described, based on highly modified species with vestigial mouthparts, reduced venation, and unique specializations.Discussion is presented on some morphological features in fossil and Recent Brachycera that have apparent phylogenetic significance but are rarely discussed. This study adds further data to the phenotypic diversity, geological history, and biogeography of a major radiation.

Cecilanthus polymerus, a novel multiparted flower from the mid-Cretaceous Rocky Point locality, Maryland

A flower from the early Cenomanian of northeastern Maryland, Cecilanthus polymerus gen. et sp. nov., is described using SEM and synchrotron X-ray microtomography. The flower has >20 strap-shaped tepals, ca. 50 spatulate stamens with embedded adaxial pollen sacs and possibly H-valvate dehiscence, and ca. 100 more-or-less plicate carpels. Floral phyllotaxis is whorled, with >10 parts per whorl, but slightly irregular. Pollen and ovules are not preserved, but locule shape suggests that the carpels are uniovulate. Similar characters occur in extant Magnoliales and the basal ANITA grade, but never in combination. In an attempt to resolve these ambiguities, we performed morphological phylogenetic analyses, with the arrangement of extant taxa constrained to trees based primarily on molecular data. With anther dehiscence and ovule number treated as unknown, Cecilanthus has several most-parsimonious positions: nested in Nymphaeales, nested in Magnoliales, sister to Laurales, and sister to Chloranthaceae. However, scoring anther dehiscence as H-valvate and ovule number as = 1, increases support for a position in Magnoliales. Cecilanthus demonstrates that the early radiation of angiosperms produced floral morphotypes unlike those in any surviving taxa, and it illustrates the value of characters such as pollen morphology and seed anatomy for phylogenetic placement of floral mesofossils.

Depositional environments and sequence stratigraphy of the Sarvak Formation in an oil field in the Abadan Plain, SW Iran

The late Albian–early Turonian Sarvak Formation is the most important carbonate reservoir of the Abadan Plain, SW Iran. Twelve microfacies were identified, representing six facies belts: lagoon, shoal, rudist biostrome, slope, proximal, and distal open marine. The lower and middle parts of the Sarvak Formation were deposited in a carbonate ramp, whereas the upper part is attributed to a carbonate shelf. For relative dating, biostratigraphic analysis recognized two main biozones as well as two biofacies. The biozones are Nezzazata-Alveolinids Assemblage Zone; and Nezzazatinella-Dicyclina Assemblage Zone with a Cenomanian and Turonian age, respectively. The biofacies are Rudist debris and Oligostegina facies, which involve a wide time-range and are dated based on their stratigraphic position. From the identification of sequence boundaries and maximum flooding surfaces, four third-order sequences in the Sarvak Formation were recognized. The sequence boundaries, dated as early Cenomanian, mid-Cenomanian, Cenomanian–Turonian, and mid-Turonian, are major disconformity surfaces, showing evidence of karstification, dissolution-collapse brecciation, and development of paleosols. The maximum flooding (MF) surfaces are discriminated by development of deep-marine facies and also high gamma-ray responses on the well logs. The identified sequences can be correlated with the sequence stratigraphic framework established for the Arabian Plate and Zagros Basin. The results from this study should contribute to the identification of exploration and production targets in the Abadan Plain and neighboring area.

†Passalopalpidae, a new family from the Cretaceous Burmese amber, as the possible sister group of Passalidae Leach (Coleoptera: Scarabaeoidea)

A new family of Scarabaeoidea is revealed from the Cretaceous amber of Myanmar (earliest Cenomanian, near 100 Ma), on a series of males and females, most in perfect condition. Passalopalpidae fam. nov., Passalopalpus cheni gen. et sp. nov., are probably extinct since a long time. Observations were made on the whole body (head, thorax, abdomen) and appendages (mouthparts, antennae, legs, wings). Most characters are remarkable and plesiomorphic, compared to Passalidae Leach, as well as to some other Scarabaeoidea. Morphological characteristics demonstrate that the fossil species is typically « passaloid », but that it cannot belongs to Passalidae. Passalopalpidae and Passalidae are clearly distinct families, with strong assumption to be sister groups. The systematic interpretation of the fossil could fill a historic gap: the sister group of Passalidae had been established previously never in a solid way. Passalids are Gondwanian, whereas passalopalpids lived on former eastern Laurasia. Vicariance of both taxa, each on one of the super-continents, seems to support recent hypotheses of phylogeny and paleobiogeography for Passalidae. Other preliminary notes are given on the morphology, biology and phylogenetic relationships of passalopalpids.

A new western European Cretaceous bryozoan genus from the early Cenomanian radiation of neocheilostomes

AbstractNeocheilostomes possessing ovicells for larval brooding originated in the late Albian and radiated explosively in the Late Cretaceous. Our understanding of this radiation is hampered by poor knowledge of the taxonomy of the earliest neocheilostomes. Here we describe a new neocheilostome genus, Ehrhardina, from shallow‐water sediments in the early Cenomanian of Western Europe. Two species (Ehrhardina voigti sp. nov. and E. pikeae sp. nov.) are referred to the new genus. Ehrhardina gen. nov. is an onychocellid characterized by large opesiae with proximolateral, symmetrical opesiular constrictions and proximolateral, long opesiular indentations, bilaterally symmetrical interzooidal avicularia and lacking spine bases, but with hyperstomial ovicells that have ectooecia formed of exterior wall calcification. Colonies are unusually large for encrusting onychocellids and multilaminar; ovicells are primitive in showing a median suture in the ectooecium. Similarities between Ehrhardina gen. nov. and Aechmella, Floridina, Floridinella, and Onychocella are discussed, and a key for the discrimination of these genera is provided. Ehrhardina gen. nov. is the oldest neocheilostome known to construct large, multilaminar colonies.

Multistratigraphic records of the Lower Cretaceous (Valanginian–Cenomanian) Puez key area in N. Italy

We present a stratigraphic investigation of a Hauterivian to Cenomanian hemipelagic succession from Col Puez, in the Dolomites (Southern Alps, northern Italy). A composite section of seven segments was studied with bio-, magneto-, and chemostratigraphy, which enabled detailed and robust age calibration of the Puez succession. It also revealed the paleoceanographic history and helped identify the important global climatic events of that period. The age of the Lower Cretaceous Puez Formation in the Dolomites is refined as late Hauterivian to early Cenomanian. Ammonoids provide a detailed biostratigraphic subdivision that forms the basis for analyses of the faunal distribution and the paleoenvironmental evolution of basins and plateaus across the Tethys. The succession consists of facies similar to those of coeval units in the Tethys, apart from the late Barremian to late Aptian interval, which is marked by a major hiatus followed by a few-meters-thick redbed of late Aptian age. The Lower Cretaceous was characterized by a weak (~1‰) positive δ13C trend, punctuated by a positive shift in the late Hauterivian corresponding to the Faraoni Level. Oxygen isotope values show a decreasing trend from the Hauterivian to the Albian/Cenomanian, which mirrors a long-term increasing trend in paleotemperatures from ~15–18°C to ~25–30°C. This is in agreement with global paleotemperature reconstructions for this period representing the onset of mid-Cretaceous super-greenhouse conditions. Nonetheless, no black shale occurs at the intervals equivalent to Aptian–Albian oceanic anoxic events (OAE), suggesting unique paleoceanographic conditions (enhanced current activity on a submarine height) on the Trento Plateau area during the mid-Cretaceous.

Albian angiosperm pollen from shallow marine strata in the Lusitanian Basin, Portugal

The evolution of angiosperms significantly changed the composition of the terrestrial vegetation during the mid-Cretaceous. In contrast to the wealth of information available on the biology and systematic relationships of early angiosperms, the temporal patterns of their evolution and radiation are poorly constrained. Here we present a continuous angiosperm pollen record from well-dated shallow marine deposits in the Lusitanian Basin, Portugal. The São Julião section provides a solid stratigraphic framework to track angiosperm pollen distribution patterns from the early Albian to early Cenomanian at mid-latitudes. In comparison to previous angiosperm pollen records from the Lusitanian basin, the section shows an extended late Albian succession and provides new insights into the diversification of early angiosperms during this important interval. Productive palynological samples were analysed and 79 different angiosperm pollen types have been recorded. Throughout the Albian angiosperm pollen represent only a minor component of the total palynoflora. The early Albian pollen record is characterized by highly diverse assemblages of monoaperturate pollen of monocot or “magnoliid” affinity and by the first appearance of polyporate and tricolpate pollen of eudicot affinity. A distinct diversification phase among tri- and poly-aperturate pollen (e.g., Cretacaeiporites, Retitrescolpites, Rousea, Striatopollis and Tricolpites) and the presence of conspicuous pollen grains assigned to Dichastopollenites characterize the middle and late Albian palynological assemblages. Thus, the section records a striking sequence of appearances of important angiosperm pollen morphologies. Monocolpates, polyporates and tricolpates appear in the early Albian whereas tricolporates appear from the early part of the late Albian onwards. Furthermore, well-constrained biostratigraphic ranges of selected angiosperm pollen from mid-latitudes are presented. In view of these new data, the temporal framework of the palynological Subzones II-B and II-C in the Potomac Group succession from the Atlantic Coastal Plain, eastern USA is revised to a middle to late Albian age.

Evolutionary and paleobiological implications of Coleoptera (Insecta) from Tethyan-influenced Cretaceous ambers

The intense study of coleopteran inclusions from Spanish (Albian in age) and French (Albian–Santonian in age) Cretaceous ambers, both of Laurasian origin, has revealed that the majority of samples belong to the Polyphaga suborder and, in contrast to the case of the compression fossils, only one family of Archostemata, one of Adephaga, and no Myxophaga suborders are represented. A total of 30 families from Spain and 16 families from France have been identified (with almost twice bioinclusions identified in Spain than in France); 13 of these families have their most ancient representatives within these ambers. A similar study had previously only been performed on Lebanese ambers (Barremian in age and Gondwanan in origin), recording 36 coleopteran families. Few lists of taxa were available for Myanmar (Burmese) amber (early Cenomanian in age and Laurasian in origin). Coleopteran families found in Cretaceous ambers share with their modern relatives mainly saproxylic and detritivorous habits in the larval or adult stages, rather than wood-boring behavior. Fifteen of the coleopteran families occur in both the Lebanese and Spanish ambers; while only five are present in both Spanish and French. Considering the paleogeographic proximity and similarity of age of the Spanish and French ambers, the small number of taxa found in common at both areas is surprising. The ancient origin for the Lebanese and Spanish ambers, the paleogeography (including some barriers for terrestrial biota) and the local paleohabitats are factors that may explain the dissimilarity with the French specimens. Wildfires are believed to be a more likely cause of resin production during the Cretaceous than infestation by beetles. Current knowledge of the beetle species found in the Cretaceous ambers is introduced.