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We describe the first maxillae and additional new specimens of Reigitherium bunodontum, a small meridiolestidan from the Late Cretaceous La Colonia Formation, Patagonia, Argentina. The new material supports a dental formula of I?, C1, P4, M3, resolves postcanine positional uncertainty and corrects previous interpretations. Our phylogeny recovers Reigitherium as a meridiolestidan allied to other bunodont Mesungulatoidea, as the sister group of the Paleocene Peligrotherium. Posterior premolars/molars of Reigitherium, and to a smaller degree Peligrotherium, are dominated by an incomplete transverse ridge running between the protoconid-metaconid in the lowers and the paracone-stylocone in the uppers, semi-symmetrical basins developing mesially and distally from these central ridges. The trigonid-derived single transverse crest results from a mesial shift of the robust metaconid, an enhancement of the basin crest stretching from the protoconid/metaconid, and a shallower trigonid basin. The mesungulatoid condition, with its complete absence of talonid, contrasts sharply with that of therians with lophs, or transverse ridges, which involved at least one talonid-derived loph resulting in two transverse crests per tooth. Mesungulatoid meridiolestidans achieved complex tooth-on-tooth occlusion with a predicted increase in herbivory/omnivory, departing from the traditional sharp-cusp insectivores plesiomorphic for meridiolestidans and Mesozoic mammals in general. Reigitherium's dramatic remodeling of the primitive meridiolestidan molar morphology, extensive continuous occlusal surface, accessory cuspules, and highly textured crenulated enamel illustrates one of most distinctive adaptations to herbivory among Mesozoic mammals. [ABSTRACT FROM AUTHOR]

Premise of research. Even though the fossil record of oviposition provides a rich archive of plant resource use, it is deficient for a fundamental reason. Very few analyzable oviposition data have been collected, particularly from the preangiospermous Mesozoic. Methodology. From northeastern China, we investigated 1817 plant specimens of the Early Cretaceous Jehol Biota (125 Ma), of which 60 specimens exhibited ovipositional damage; 3886 specimens of the Middle Jurassic Yanliao Biota (165 Ma) revealed 296 specimens with ovipositional damage; and 408 specimens from the Late Triassic Beipiao Biota (205 Ma) yielded 19 specimens with ovipositional damage. First, we analyzed herbivore ovipositor structure of 68 Jehol and Yanliao insect species, resulting in nine ovipositor morphotypes. Second, we analyzed oviposition lesions of plant specimens from all three biotas, yielding 15 oviposition damage types (DTs). Third, we linked ovipositor morphotype to oviposition DTs. Pivotal results. The most heavily oviposited Jehol plant group was conifers, particularly Liaoningocladus boii ; Equisetites (horsetails) were subordinately attacked. For the Yanliao Biota, the most intensely oviposited plant group was bennettitaleans, particularly Anomozamites , responsible for 46.6% of all ovipositor associations in the total Jehol-Yanliao-Beipiao data set. The conifer Yanliaoa and the ginkgophyte Ginkgoites had subordinate levels of oviposition. The Beipiao Biota revealed a more balanced distribution of oviposition, with cycads and ferns having the greatest ovipositional damage. Conclusions. These three time slices, separated by two 40-million-year intervals, indicate major shifts in oviposition preferences. An examination is warranted into the factors promoting the pronounced oviposition levels on Yanliao Anomozamites , a bennettitalean. [ABSTRACT FROM AUTHOR]

In order to classify and taxonomically describe the first two fossil Othiini (Coleoptera: Staphylinidae: Staphylininae) species from three well‐preserved specimens in Cretaceous Burmese amber, a phylogenetic analysis was conducted, combining extant and extinct taxa. A dataset of 76 morphological characters scored for 33 recent species across the subfamilies Staphylininae and Paederinae was analysed using maximum parsimony and Bayesian inference methods. The many differing phylogenetic hypotheses for higher‐level relationships in the large rove beetle subfamilies Staphylininae and Paederinae were summarized and their hitherto known fossil record was reviewed. Based on the analyses, the new extinct genus Vetatrecusgen.n. is described with two new species: V. adelfiaesp.n. and V. secretumsp.n. Both species share character states that easily distinguish them from all recent Othiini and demonstrate a missing morphological link between subfamilies Staphylininae and Paederinae. This is the first morphology‐based evidence for the paraphyly of Staphylininae with respect to Paederinae, suggested earlier by two independent molecular‐based phylogenies of recent taxa. Our newly discovered stem lineage of Othiini stresses the importance of fossils in phylogenetic analyses conducted with the aim of improving the natural classification of extant species. It also suggests that the definitions of Staphylininae and Paederinae, long‐established family‐group taxa, may have to be reconsidered. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:817F39C4-F36B-4FD9-96CD-5F8FB064C39E. The first fossil Othiini found in Burmese amber is described in the extinct genus Vetatrecus gen.n. with two species V. adelfiae sp.n. and V. secretum sp.n.To robustly resolve the systematic position of the extinct genus, we applied morphology‐based phylogenetic analysis.With its unique morphology Vetatrecus combines characters that in recent taxa only occur separately in different subfamilies. This stresses the value of fossils for systematics. [ABSTRACT FROM AUTHOR]

An unusually large acariform mite is described as Immensmaris chewbaccei gen. et sp. nov. from the Cretaceous (ca. 100 Ma) Burmese amber of Myanmar. With an idiosoma plus gnathosoma more than a centimetre long, it represents the largest unequivocal fossil mite ever recorded and approaches the maximum size of the largest living Acariformes today. Although some details of the dorsal idiosoma are equivocal, the new fossil appears to belong to Smarididae (Prostigmata: Parasitengona: Erythraeoidea) and also represents the largest erythraeoid mite ever discovered, indicating a clade of giant, possibly arboreal, mites in the Late Cretaceous of southeastern Asia. [ABSTRACT FROM AUTHOR]

In 1907 the French palaeobotanist Octave Lignier published a study of Jurassic fossil wood that was to become a seminal palaeoxylological work. Although the names he established were often used or recombined and his contribution is still often quoted today, the original material was never re-studied, except for one of the fifteen originally published samples. This material was only recently been rediscovered, after it was thought to be lost since the 1980s. Here we make use of this opportunity to re-evaluate stratigraphical attributions and ages of Lignier's original samples, to review their nomenclatural status and discuss their taxonomical assignment. Three new combinations are introduced: ( Agathoxylon tranchantii (Lignier) comb. nov., Baieroxylon divesence (Lignier ex Seward) comb. nov., Brachyoxylon blevillense (Lignier) comb. nov.), and a new species ( Agathoxylon crasseradiatum sp. nov.) is published based on Lignier's material. Baieroxylon divesence is anatomically closely related to modern ginkgo and hence an interesting milestone is the little documented history of Ginkgoales wood. [ABSTRACT FROM AUTHOR]

Schemes and criteria are developed for using the measured and modeled geotemperatures for studying the thermal regime of the source rock formations, as well as the tectonic and sedimentary history of sedimentary basins, by the example of the oil fields of the Yamal Peninsula. The method of paleotemperature modeling based on the numerical solution of the heat conduction equation for a horizontally layered solid with a movable upper boundary is used. The mathematical model directly includes the climatic secular trend of the Earth’s surface temperature as the boundary condition and the paleotemperatures determined from the vitrinite reflectance as the measurement data. The method does not require a priori information about the nature and intensities of the heat flow from the Earth’s interior; the flow is determined by solving the inverse problem of geothermy with a parametric description of the of the sedimentation history and the history of the thermophysical properties of the sedimentary stratum. The rate of sedimentation is allowed to be zero and negative which provides the possibility to take into account the gaps in sedimentation and denudation. The formation, existence, and degradation of the permafrost stratum and ice cover are taken into account as dynamical lithological-stratigraphic complexes with anomalously high thermal conductivity. It is established that disregarding the paleoclimatic factors precludes an adequate reconstruction of thermal history of the source-rock deposits. Revealing and taking into account the Late Eocene regression provided the computationally optimal and richest thermal history of the source-rock Bazhenov Formation, which led to more correct volumetric-genetic estimates of the reserves. For estimating the hydrocarbon reserves in the land territories of the Arctic region of West Siberia by the volumetric-genetic technique, it is recommended to use the Arctic secular trend of temperatures and take into account the dynamics of the Neoplesitocene permafrost layers 300-600 m thick. Otherwise, the calculated hydrocarbon reserves could be underestimated by up to 40%. [ABSTRACT FROM AUTHOR]

The Western Qinling has been acknowledged to witness superimposed orogeny including north subduction of Paleotethys ocean and collision between North China and South China blocks; however, the precise timing constraints on transition of tectonic regime are remaining enigmatic. The Wenquan composite batholith comprising five phases and mafic enclaves is an ideal example to unlock this puzzle. The host granitoids are felsic, metaluminous to peraluminous, and high-K calc-alkaline to shoshonitic suite with I-type affinity. The mafic enclaves, however, are intermediate, and high-K calc-alkaline to shoshonitic. Zircon ages of multiple phases indicate an episodic growth lasting nearly 30 million years ranging from 238, 228, 218 to 208 Ma, consistent to Triassic igneous activity recording a transition regime from a subduction setting to a syn-collision setting and a post-collision setting in Western Qinling. Lead isotopes of whole-rock and K-feldspar at Wenquan and Lu-Hf isotopes of zircons separated from biotite monzogranite porphyry, porphyritic monzogranite, monzogranite porphyry, and hosted mafic enclaves suggest that the heat and the hot mafic melt initiated by the break-off of the northward subducting South China block lithosphere triggered partial melting of the Mesoproterozoic subcontinental lithospheric mantle to produce mafic magmas, and the underplated mafic magmas caused partial melting of the shallow subducted Mesoproterozoic lower crust generating granitic magmas at Wenquan. Combined our field observations and petrology study with a holistic review on previous geochronological and geochemical data of Triassic granitoids throughout the Western Qinling, we in this contribution proposed that the Triassic igneous activity in the Western Qinling corresponding to superimposed orogeny evolved from the northward subduction of Palaeotethys ocean (250–235 Ma) through syn-collision (228–215 Ma) to post-collision (215–185 Ma) between the North China and South China blocks. [ABSTRACT FROM AUTHOR]

Despite increasing claims of pre-Cretaceous angiosperms, whether there really are angiosperms in the Jurassic is apparently still an open question for many people before further evidence is available. This question can only be answered by studying more Jurassic plant fossils. Here we report a fossil angiosperm,Yuhania daohugouensisgen. et sp. nov, from the Middle Jurassic of Inner Mongolia, China. The plant includes connected stem, leaves, flowers, aggregate fruits, fruitlets, and seeds within fruitlets. The leaves are helically arranged along the curving stem, linear in shape, with 5–6 parallel veins. The aggregate fruit is pedicellate, composed of over 20 carpels/fruitlets helically arranged. Each fruitlet encloses a seed. The reproductive organs in various stages are found in the same plant, allowing us to understand the development ofYuhania. The occurrence ofYuhaniain the Middle Jurassic re-confirms the Jurassic history for angiosperms that has been suggested by other independent research and adds to the on-going study on the early evolution of angiosperms. [ABSTRACT FROM PUBLISHER]

The study of Middle Triassic (Ladinian) nautiloids from three successive ammonoid zones, and two sub-zones, of the Southiberian Triassic Muschelkalk facies (Betic Cordillera, southern Spain) has allowed the identification of the following species:Mojsvaroceras haasiParnes, 1986,M. kummeliParnes, 1986,Germanonautilus bidorsatus(von Schlotheim, 1820),G. tridorsatus(Böttcher, 1938),Grypoceras?quadrangulum(Beyrich, 1866a),Indonautilus awadiKummel, 1960,I. privatus(Mojsisovics, 1882) andPicardiceras picardiParnes, 1986. The possibly endemicIndonautilus innocenssp. nov. is described herein. Although some of these species have already been reported from the Betic Cordillera, most are described in detail and illustrated for the first time and their stratigraphical distributions determined accurately for this region. Of the nine nautiloid species described herein, five are known from the Germanic and Tethyan provinces and four are restricted to the Sephardic Province. The genusPicardicerasis typical of the Sephardic Province. It appears that during the Ladinian the Betic Cordillera was a palaeogeographical region for faunal exchange between Central Europe, North Africa and the Middle East. http://zoobank.org/urn:lsid:zoobank.org:pub:98032616-2778-439B-B6D4-D32BFF7CCB83 [ABSTRACT FROM PUBLISHER]

It has generally been held that the locomotory habits of sauropodomorph dinosaurs moved in a relatively linear evolutionary progression from bipedal through “semi-bipedal” to the fully quadrupedal gait of Sauropoda. However, there is now a growing appreciation of the range of locomotory strategies practiced amongst contemporaneous taxa of the latest Triassic and earliest Jurassic. Here we present on the anatomy of a hyper-robust basal sauropodomorph ilium from the Late Triassic–Early Jurassic Elliot Formation of South Africa. This element, in addition to highlighting the unexpected range of bauplan diversity throughout basal Sauropodomorpha, also has implications for our understanding of the relevance of “robusticity” to sauropodomorph evolution beyond generalized limb scaling relationships. Possibly representing a unique form of hindlimb stabilization during phases of bipedal locomotion, the autapomorphic morphology of this newly rediscovered ilium provides additional insight into the myriad ways in which basal Sauropodomorpha managed the inherited behavioural and biomechanical challenges of increasing body-size, hyper-herbivory, and a forelimb primarily adapted for use in a bipedal context. [ABSTRACT FROM AUTHOR]

We document the occurrence of Upper Triassic fusain in northern Arizona, southern Utah and northern New Mexico in latest Carnian(?) to Norian-age alluvial strata of the Monitor Butte Formation and the Sonsela and Painted Desert members of the Petrified Forest Formation (Chinle Group). The fusain, identified by standard techniques of macroscopic and microscopic morphology, and resistance to chemical oxidation, is present at multiple stratigraphic horizons at several locations that are approximately correlative, although separated by several hundred km. The morphology of this fossil charcoal includes large, partially charred silicified to coalified logs, completely charred smaller limbs, charcoal fragments reworked in fluvial deposits, and particulate fusain disseminated in sediments. The apparent rarity of fusain in Triassic strata previously was cited as evidence for relatively low levels (compared to modern) of atmospheric oxygen and the consequent infrequent occurrence of wildfire during this time interval. However, our findings demonstrate a significantly greater abundance of fusain in Upper Triassic strata than previously acknowledged. Therefore, we suggest that wildfire was not an unusual occurrence during the Late Triassic. This conclusion supports recent experimental studies and geochemical models that indicate atmospheric oxygen levels at or above modern levels during the Late Triassic. [ABSTRACT FROM AUTHOR]

The ultrastructure of the leaf cuticle of Mesozoic conifers of the family Miroviaceae – Mirovia Reymanówna – was studied for the first time. The leaf cuticles of three Mirovia species from different localities and ages were investigated: Mirovia kazachstanica Nosova et Kiritchkova from the Lower Jurassic of the Mangyshlak Mountains (Kazakhstan), Mirovia macrophylla (Florin) Nosova from the Middle Jurassic of the Andøya Island (northern Norway) and Mirovia sibirica (Samylina) Bose et Manum from the Lower Cretaceous of the Lena River Basin (Russia). The data obtained from TEM analysis allow to give a detailed description of the cuticle structure of both the abaxial and adaxial surfaces. The cuticular membrane of Mirovia leaves is made up of the cuticle proper, composed of an outer polylamellate layer and an inner granular and homogeneous layer, and a cuticular fibrillate layer. The cuticle ultrastructures of the studied Mirovia species were compared with each other, and also with other fossil and extant conifers. [ABSTRACT FROM AUTHOR]

The Early Triassic, following the end-Permian mass extinction, was an interval of severe low diversity. Increasing amounts of evidence demonstrate that variable environmental stresses were widespread and intense after the end-Permian mass extinction. Here we report biomarkers from lowest Triassic to lower Middle Triassic strata in South China (Qingyan and Chaohu sections), including biomarkers for environmental stress (2-methyl hopane index) and eukaryotic algae (steranes and C 21 n -alkylbenzene ratio). Using the 2-methyl hopane index, we detected the persistence of environmental stress during most of the Early Triassic. Using steranes and the C 21 n -alkylbenzene ratio, we found a gradual increase in the biomass of eukaryotic algae during the Early to early Middle Triassic. A decrease in environmental stress in the Qingyan section (Leidapo Member) during the early Middle Triassic was synchronous with the “explosion” of the Qingyan Biota, which is characterized by a high abundance and diversity of invertebrate marine animals. Because the environmental stresses revealed by the 2-methyl hopane index encompass various factors (e.g., pH and temperature), we cannot identify the exact stresses at that time; however, our results reflect the amelioration of harsh environments for life during the interval of complete biotic recovery. [ABSTRACT FROM AUTHOR]

A complete redescription ofCathayornis caudatusHou, 1997 is provided based on new information from a resin cast of the holotype, leading to reinterpretation of many morphological features of this initially poorly diagnosed taxon. Detailed comparisons across various specimens referred to Cathayornithidae Zhouet al., 1992 indicate thatSinornis santensis,Cathayornis yandica,C. caudatusandEocathayornis walkeriare valid taxa, but thatC. chabuensisshould be regarded as anomen dubium. The holotype and referred specimens ofC. chabuensisdiffer significantly in morphology, indicating that they do not belong to the same species. A comprehensive phylogenetic analysis targeted at Mesozoic birds reveals that neither Cathayornithidae Zhouet al., 1992 norCathayornisZhouet al., 1992 are monophyletic, and thatC. yandicacan be regarded as the only species in a monospecific Cathayornithidae. The holotype of ‘C. caudatus’ is assigned to the genusHouornisgen. nov., and a taxonomic reassessment of other ‘cathayornithids’ is presented. http://zoobank.org/urn:lsid:zoobank.org:pub:0B1A404A-CC6A-4609-8CC5-C0DD62983C9A [ABSTRACT FROM PUBLISHER]

The plant megafossil genus Linguifolium Arber 1917 is chiefly known from the Middle and Upper Triassic of Gondwana. The range of Linguifolium extended beyond Gondwana by the Late Triassic, persisting there through the earliest Jurassic (Hettangian). The parent plants probably grew in a well-watered, canopied environment. Diagnoses of the genus and four of its species - Linguifolium tenison-woodsii (Shirley 1898) Retallack 1980, L. waitakiense Bell in Bell et al. 1956, L. parvum Holmes & Anderson in Holmes et al. 2010, and L. steinmannii (Solms-Laubach 1899) Arber 1917 - are emended with particular reference to venation and leaf morphology; consequently, the stratigraphic ranges of the species have been more precisely defined. Coalescent venation has previously been reported in some species of Linguifolium and is identified in new material described herein. Although the vast majority of specimens assigned to the genus are from the Upper Triassic, none shows coalescent venation. This character is entirely restricted to the Middle Triassic, in particular to two species: L. waitakiense and L. parvum. Linguifolium tenison-woodsii is restricted to the Carnian-lowermost Norian of Australia and South Africa and is recorded here for the first time from the Tarong Basin (upper Carnian), Queensland. Confusion regarding assignment of specimens to this species from the Middle Jurassic of Queensland is resolved. [ABSTRACT FROM AUTHOR]

Morphological and epidermal characters of Protophyllocladus Berry are documented in detail based on the investigation of specimens from the Cretaceous of western Greenland, western Siberia and Sakhalin (Russian Far East). Two new species, Protophyllocladus magathianus Nosova sp. nov. from the Arkovo Formation (Coniacian) of Sakhalin and P. groenlandicus Nosova sp. nov. from the Atane Formation (Albian – Cenomanian) of western Greenland, are described. The new data on the epidermal structures of phylloclades of this genus allow us to emend the generic diagnosis. The morphology and epidermal features of Protophyllocladus are similar to those of the modern genus Phyllocladus Richard, suggesting the podocarpaceous affinity of Protophyllocladus . [ABSTRACT FROM AUTHOR]

Abstract: Volcanic episodes are considered to be potentially important drivers of many mass extinction events in Earth history, when a sharp decrease in the diversity and abundance of macroscopic organisms occurred. Such events are hypothesised to be associated with volcanic sulphur dioxide (SO2) release. The effect of volcanism on atmospheric composition varies widely and is related to the magnitude and duration of the volcanic episode. Currently, there are limited methods for detecting the timing of SO2 release in the geological past. In field conditions, the influence of SO2 on plants can be difficult to separate from the effects of other volcanic emissions, which enter via stomata and can affect plant physiology, anatomy and morphology. In order to assess the direct effects of SO2 associated with palaeo-volcanic episodes, we conducted a six month growth chamber experiment growing plants under control (zero parts per million (ppm)) and continuous elevated (0.2ppm) sulphur dioxide atmospheres. Leaf morphological responses of ten species representative of Mesozoic gymnosperm and fern fossil floras were examined using cryo-scanning electron microscopy. Here we show that expanded, fully mature leaves record unambiguous damage structures associated with injury from SO2 fumigation. In SO2 treated plants, leaves were smaller and did not persist; distinct raised areas of cuticle surrounding stomata appeared; surface waxes altered; blistering of the cuticle occurred; and the stomatal complex became distorted. These results have clear implications for application to the fossil record as many of the observed damage structures have the potential to be preserved in fossil plant cuticle and thus allow precise pinpointing of elevated SO2 episodes in the geological past. [Copyright &y& Elsevier]

The following provinces are recognized in the Late Cretaceous within the Asian part of the Siberian-Canadian paleofloristic region: Chulym-Yenisei, Lena-Vilyui, North Siberian, Verkhoyansk, Mountain Okhotsk-Chukotka, Anadyr', Amur, Sikhote-Alin, and Sakhalin-Japanese. It is proposed to consider the Central Asian (Turan) Province as belonging to the Euro-Sinian paleofloristic region. In the Cenomanian, the province also included the area of the southern Chulym-Yenisei Depression. In the maritime and northern provinces, a considerable occurrence of Mesozoic relics compared to the southern and continental ones is recorded. Similarity and distinctions between the floras of different provinces varied during the Late Cretaceous. Climatic conditions played a considerable role in species diversity and degree of differentiation or unification of the floras. [ABSTRACT FROM AUTHOR]

Abstract: Revision of the Mesozoic fossil wood record for Eastern Asia led to the recognition of a new type of homoxylous wood radial pitting, called here “the japonicum type”. This anatomical feature has a limited distribution in both time and space. On this basis a new genus, Shimakuroxylon gen. nov., is recognized. It has limited biostratigraphical interest, ranging from the Jurassic to the Cretaceous. Paleogeographically, however, it is bound to these terranes which lined southernmost Eastern Asia during the Jurassic (Lhasa, Indochina, Semitau, etc.). Being also found in the Outer Zone of Southwest Japan, the origin of which is still a matter of debate, Shimakuroxylon points out a southern cradle for this tectonic unit. The genus distribution also suggests it is an indicator for warm and wet climates. [Copyright &y& Elsevier]

The structure of the sporopollenin wall of fossil megaspores can be usefully applied to the determination of morphological similarities and differences between species and genera, which in turn can aid determinations of botanical relationships. Nine species belonging to seven genera of lycopsid megaspores from European Mesozoic successions that have been examined in thin section under a transmission electron microscope are discussed in this paper. Of these, seven are considered to be referable to the Selaginellales, namely Bacutriletes pragensisroman Echitriletes zemechensisroman Erlansonisporites sp. ‘pseudomoravica’ type, Horstisporites cenomanicensisroman Kerhartisporites kleiniiroman K. srebrecensisroman Ricinospora sp. and Verrutriletes maloninensis. The structure of the exospore of Aneuletes patera, an alete species of hitherto uncertain affinity, also suggests that this has selaginellalean origins. The construction of the wall of Echitriletes lanatus, however, resembles that of representatives of the Isoetales and implies derivation from a family within, or related to, one or other of these lycopsid orders that is now extinct. Along with aspects of their gross morphology, significant differences between the structure of the exospore of E. lanatus and E. zemechensis suggest that they do not belong in the same morphological genus. The value of the differentiating Kerhartisporites from Erlansonisporites is questioned. [ABSTRACT FROM AUTHOR]

Abstract: The Bennettitales are a Mesozoic group of gymnosperms with complex reproductive organs that figure prominently in hypotheses on the ancestry and origin of angiosperms. However, the exact phylogenetic position of the Bennettitales is still debated, due in part to the scarcity of conclusive fertile remains from the Triassic. In this study we reconstruct a bennettitalean flower from isolated parts from the Carnian (Upper Triassic) of Lunz in Lower Austria, including Cycadolepis wettsteinii scale leaves, Haitingeria krasseri pollen organs, and Bennetticarpus wettsteinii ovulate organs/seed cones, based on correspondences in gross morphology and epidermal anatomy. The flower has small pollen organs with spreading and well-exposed pollen sacs; pollen sacs are not organised in synangia, and the ovulate organ is characterised by a low number of relatively large seeds and a large number of interseminal scales in relation to ovules/seeds. The flower lacks several of the characteristic features seen in geologically younger bennettitaleans, including fused, inwardly curved pollen organs and large number of small seeds. The association of these isolated organs to a single flower provides a rare opportunity to assess the attribution of these early representative of the Bennettitales, and sheds new light on the evolutionary history and phylogenetic position of this ancient group of seed plants. [Copyright &y& Elsevier]

Background: †Saurichthyiformes were a successful group of latest Permian–Middle Jurassic predatory actinopterygian fishes and constituted important, widely-distributed components of Triassic marine and freshwater faunas. Their systematic affinities have long been debated, with †saurichthyiforms often being aligned with chondrosteans, a group today comprising sturgeons and paddlefishes. However, their character-rich endocranial anatomy has not been investigated in detail since the first half of the 20th century. Since then, major advances have occurred in terms of our understanding of early actinopterygian anatomy, as well as techniques for extracting morphological data from fossils. Results: We used μCT to study the internal cranial anatomy of two of the stratigraphically oldest representatives of †Saurichthys, from the Early Triassic of East Greenland and Nepal. Our work revealed numerous previously unknown characters (e.g., cryptic oticooccipital fissure; intramural diverticula of braincase; nasobasal canals; lateral cranial canal; fused dermohyal), and permitted the reevalution of features relating to the structure of cranial fossae, basicranial circulation and opercular anatomy of the genus. Critically, we reinterpret the former †saurichthyiform opercle as an expanded subopercle. For comparison, we also produced the first digital models of a braincase and endocast of a sturgeon (A. brevirostrum). New information from these taxa was included in a broad phylogenetic analysis of Actinopterygii. †Saurichthyiforms are resolved as close relatives of †Birgeria, forming a clade that constitutes the immediate sister group of crown actinopterygians. However, these and other divergences near the actinopterygian crown node are weakly supported. Conclusions: Our phylogeny disagrees with the historically prevalent hypothesis favoring the chondrostean affinities of †saurichthyiforms. Previously-proposed synapomorphies uniting the two clades, such as the closure of the oticooccipital fissure, the posterior extension of the parasphenoid, and the absence of an opercular process, are all widespread amongst actinopterygians. Others, like those relating to basicranial circulation, are found to be based on erroneous interpretations. Our work renders the †saurichthyiform character complex adequately understood, and permits detailed comparisons with other stem and crown actinopterygians. Our phylogenetic scheme highlights outstanding questions concerning the affinity of many early actinopterygians, such as the Paleozoic–early Mesozoic deep-bodied forms, which are largely caused by lack of endoskeletal data. [ABSTRACT FROM AUTHOR]

The article focuses on the proposal to conserve the name Scytophyllum Bornem for the fossil of family Pteridospermae and Peltaspermopsida at the place of Scytophyllum. It informs that the genus Scytophyllum was established for distinctive vegetative foliage of Triassic age which now belongs to Mesozoic pteridosperms.

The article focuses on a proposal to conserve the botanical family name Lepidopteris against Aspidioides. The genus Lepidopteris is vegetative foliage types of the extinct Mesozoic pteridosperms Peltaspermales which is distinctive genus-marker of Triassic age. The author also thanks Valentina Bublik for her help and advice.

Summary Why ichthyosaurs — marine Mesozoic reptiles — disappeared before the dinosaur extinction has remained a mystery. New research suggests they may have gone extinct stepwise, during one of the most extreme greenhouse periods in the history of complex life-forms. [ABSTRACT FROM AUTHOR]