Ichnology of an ephemeral lacustrine/alluvial plain system: Jurassic East Berlin Formation,Hartford Basin,USA

A trace fossil assemblage from the Lower Jurassic East Berlin Formation of the Newark Supergroup, Hartford Basin, New England, USA, includes: Scoyenia gracilis, Skolithos ichnosp., Palaeophycus striatus, Planolites montanus, Fuersichnus ichnosp., fusiform burrows, pelleted material, an escape structure, and large burrows.

This assemblage is assigned to the Scoyenia ichnofacies. Specific lebensspuren are not limited to specific lithofacies; instead, their initial distribution seems to have been influenced principally by water availability within an ephemeral lacustrine/alluvial plain system. Other factors in distribution may have included amounts of organic matter, patterns of sedimentation, sediment grain size, biotic factors (settling from invertebrate drift, competition), and additional abiotic factors (wind deflation, waves, currents, desiccation, soft‐sediment deformation, evaporite formation, pedoturbation).

Extreme environmental conditions within the original depositional setting strongly influenced the availability of water which, in turn, strongly influenced the paleoecology of burrowing invertebrates in this nonmarine system.     

The Trace Fossil Diplopodichnus from the Lower Jurassic Lacustrine Sediments of Central China and the Isopod Armadillidium vulgare (Pillbug) Lebensspuren as its Recent Analogue

The trace fossil Diplopodichnus isp. was identified in lacustrine siliciclastics of the Lower Jurassic Anyao Formation in the Henan Province, central China. This is the youngest occurrence of this ichnogenus. It is similar to some variants of recent surface traces of the isopod Armadillidium vulgare (pillbug) crawling on soft mud in temporal puddles. Therefore, isopods are suggested to be producers of the described Diplopodichnus isp. It seems that isopods should be taken into account as important component of deep lacustrine ecosystems by the Early Jurassic.     

Fossil coniferous wood from the Middle Jurassic of Liaoning Province, China

Silicified coniferous wood was collected from the Lanqi Formation (late Middle Jurassic in age) at Shebudaigou Village, Liaoning Province, China. Three taxa are identified, namely Pinoxylon dacotense Knowlton, Xenoxylon phyllocladoides Gothan, and Araucariopitys sp. Based on these new data, and those of other fossil plants reported previously from the same formation, we consider the climate during the deposition of the Lanqi Formation was subtropical, humid and seasonal. In this respect the Lanqi flora differs from the coeval Shimengou and Longmen floras from North China. The Longmen flora was deposited during more humid, subtropical conditions, while the Shimengou Formation indicates that the climate was warm temperate and dry. Our data would suggest that the Late Jurassic climatic pattern was initiated as early as the late Middle Jurassic.     

吐鲁番拗陷北部中侏罗世孢粉植物群

报道了新疆吐鲁番拗陷北部勒1、米1、山1和墩1井中侏罗世孢粉化石52属81种。建立了本区中侏罗世孢粉组合：Cyathidites-Psophyosphaera-Cycadopite组合、Cyathidites-Quadraeculina-Classopollis组合和Cyathidites-Callialas-porites-Classopollis组合。它们分别产自西山窑组、三间房组和七克台组。根据孢粉组合特征及其对比,认为3个组合的地质时代属阿林－巴通期。经研究表明,中侏罗世早期的植被是以银杏、苏铁类和松柏类等乔木为主体,并伴有桫椤科树蕨及紫萁科和卷柏科等草本植物。古气候应属温暖潮湿的亚热带气候。至中侏罗世中晚期,掌鳞杉科植物在植被中占主导地位,指示当时的气候趋于干旱。     

Two new species of Sinosmylites Hong (Neuroptera, Berothidae) from the Middle Jurassic of China, with notes on Mesoberothidae

Two new species of the genus Sinosmylites Hong are described from the Middle Jurassic locality at Daohugou (Inner Mongolia, China): Sinosmylites fumosussp. n. and Sinosmylites rasnitsynisp. n. This is the oldest known occurrence of the family Berothidae. The berothid affinity of this genus is confirmed by examination of the hind wing venation characteristic of the family. The Late Triassic family Mesoberothidae may represent an early group of Berothidae.     

Two new species of Archaeohelorus (Hymenoptera,Proctotrupoidea, Heloridae) from the Middle Jurassic of China

Two new fossil species, Archaeohelorus polyneurus sp. n. and A. tensus sp. n., assigned to the genus Archaeohelorus Shih, Feng & Ren, 2011 of Heloridae (Hymenoptera), are reported from the late Middle Jurassic, Jiulongshan Formation of Inner Mongolia, China. Based on the well-preserved forewings and hind wings of these specimens, the diagnosis of the Archaeohelorus is emended: forewing 2cu-a intersecting Cu and Rs+M at the same point or postfurcal, and hind wing may have tubular veins C, Sc+R, R, Rs, M+Cu, M and Cu distinct, or simplified venation. The new findings also elucidate the evolutionary trend of forewing and hind wing venation and body size for the Heloridae from the late Middle Jurassic to now.     

A new species of the extinct genus Austrohamia (Cupressaceae s.i.) in the Daohugou Jurassic flora of China and its phytogeographical implications

A new conifer,Austrohamia acanthobractea,sp.nov.,is described from the Jurassic Daohugou flora,Inner Mongolia Autonomous Region,China.The material consists of impressions represented by well-preserved ...     

A new Xinjiangchelyid turtle (Testudines, Eucryptodira) from the Jurassic Qigu Formation of the southern Junggar Basin, Xinjiang, north-west China

A new eucryptodiran turtle, Xinjiangchelys qiguensis sp. nov. from the Upper Jurassic (Oxfordian — ?Kimmeridgian) Qigu Formation of the southern Junggar Basin (north‐west China) is described. The type material consists of a partial skeleton, including the complete carapace, plastron, nearly all cervical vertebrae, both scapulae, the pelvis and one ulna. It is clearly identifiable as a basal eucryptodire since it lacks the mesoplastron. It is distinguished from other species of Xinjiangchelys by several autapomorphies of the carapace and plastron, such as the first and fifth vertebrals extending on the peripherals, the plastron with three pairs of gulars, and an intergular which does not contact the hyoplastron. In the postcranium, the scapula with a long acromial and a small scapular process, the pelvis with a short ilial shaft and the elongated cervical vertebrae are characteristic. A new phylogenetic analysis of the in‐group phylogeny of the Xinjiangchelyidae is proposed and discussed, resulting in a new classification of the family. Xinjiangchelys (Toxocheloides) narynensis is regarded as a nomen dubium. Shartegemys is referred to Xinjiangchelys, whereas the holotypes of ‘Plesiochelys’chungkingensis and ‘P’. latimarginalis are excluded from the genus Xinjiangchelys but included in the Xinjiangchelyidae.     

New Phoenicopsis leaves (Czekanowskiales) from the Middle Jurassic Daohugou Biota,China and their roles in phytogeographic and paleoclimatic reconstruction

The Middle Jurassic Jiulongshan Formation, distributed in the Daohugou area, Ningcheng County, Inner Mongolia, China, is famous for yielding abundant, well-preserved fossil vertebrates and invertebrates. However, only a few fossil plants have been reported to date. In this paper, one new species of Czekanowskiales, Phoenicopsis (Windwardia) daohugouensis n. sp. is described based upon leaf morphology and epidermal characters. The new species represents the first record of Czekanowskiales from the Daohugou Biota. The discovery of the new species reveals the significance of the Daohugou flora as one of the deciduous forests in the temperate-warm temperate zone of Eurasia during the Middle Jurassic.     

云南早侏罗世一新具嵴冠兽脚类恐龙

报道了具嵴冠的兽脚类恐龙一新属种,安龙堡双柏龙(Shuangbaisaurus anlongbaoensis gen.et sp.nov.).双柏龙发现于云南省楚雄彝族自治州双柏县下侏罗统冯家河组中,保存了部分头骨带下颌.双柏龙沿两侧眼眶背缘向上有嵴冠发育,这在其他兽脚类中未曾报道过.与其他早侏罗世体型较大且具一对矢状嵴冠的兽脚类(双嵴龙属和中国龙属)相比,双柏龙还独具一些特征组合,如相对较高的前颌骨体、抬高的前颌骨腹缘、后腹向延伸的轭骨后突及较小的上颞孔.比较研究表明,尽管中国“双嵴龙”(“Dilophosaurus”sinensis)可能应归入中国龙属(Sinosaurus),但未必属于模式种.双柏龙的发现将有助于研究基干兽脚类的演化,尤其是各类头骨骨饰在其中的作用.     

New mayfly nymphs from the Jurassic of Northern and Northeastern China (Insecta: Ephemeroptera)

Four new species of mayfly nymphs, Furvoneta relicta sp. nov., Clavineta eximia sp. nov. (originally Mesoneta antiqua), Mesobaetis latifilamentacea sp. nov., and Stackelbergisca cylindrata sp. nov. are described from the Jurassic of China. All these species may have inhabited lakes rather than flowing water. The geological age and stratigraphical correlation of the nymph-bearing strata are briefly reviewed.     

First record of Eretmophyllum (Ginkgoales) with well-preserved cuticle from the Middle Jurassic of the Ordos Basin,Inner Mongolia,China

The genus Eretmophyllum, a characteristic and widespread taxon of the order Ginkgoales, is restricted in the Mesozoic floras of Eurasia. In China, although some specimens were assigned to Eretmophyllum based on gross leaf morphology, none have epidermal structure, which is essential for species delimitation within this genus. In this paper, we describe a new species, Eretmophyllum neimengguensis n. sp., from the Middle Jurassic Yan’an Formation of the Ordos Basin, China. This is the first record of the genus Eretmophyllum (Ginkgoales) from the Ordos Basin as well as from China based upon the gross leaf morphology and the epidermal structure. The new record significantly extends the stratigraphic and geographic distribution of Eretmophyllum in China and Eurasia. It also improves our understanding of its leaf morphology, epidermal structure, and past diversity. The taxonomic position and the stratigraphic and geographical range of the genus Eretmophyllum are discussed. Briefly, leaf morphological and epidermal characters of the new species, associated plant assemblages, and sedimentology indicate that the regional climate of the Ordos Basin was warm and humid with seasonal temperature and precipitation fluctuations in warm-temperate zone during the Middle Jurassic. Furthermore, given the relationship between the distribution/diversity of the genus and the climate, the genus Eretmophyllum may be confined to the warm-temperature climate, is intolerant of heat and frost, and can be considered as an indicator of humid and warm climatic conditions.     

A new long-proboscid genus of Pseudopolycentropodidae (Mecoptera) from the Middle Jurassic of China and its plant-host specializations

We describe a new genus and species of Mecoptera with siphonate mouthparts, Sinopolycentropus rasnitsynigen. et sp. n., assigned to the family Pseudopolycentropodidae Handlirsch, 1925. The specimen was collected from late Middle Jurassic nonmarine strata of the Jiulongshan Formation in Inner Mongolia, northeastern China. The new material provides additional evidence for an early diversification of pseudopolycentropodids that was ongoing during the Middle Jurassic. This diversity also adds to the variety of known pseudopolycentropodids with tubular proboscides that apparently fed on ovulate fluids produced by Mesozoic gymnosperms.     

Two new species of Palaeoarthroteles Kovalev and Mostovski (Diptera, Rhagionidae) from the Callovian-Oxfordian (Jurassic) Daohugou biota of China

Two new species of fossil snipe flies (Rhagionidae) from the Daohugou Formation of Chifeng City in Inner Mongolia Autonomous Region (northeastern China) are described as Palaeoarthroteles jurassicus nov. sp. and P. pallidius nov. sp. They are the first record of the genus Palaeoarthroteles Kovalev and Mostovski beyond Siberia, which have implications for stratigraphic correlation of the formations in which they are found.     

Sobralispongia densespiculata, a new coralline sponge from the Upper Jurassic of Portugal

From the Kimmeridgian (Upper Jurassic) of Portugal, the coralline sponge Sobralispongia densespiculata nov. gen. and nov. sp. is described. Main characteristics are a crustose habit, a primary spicule skeleton of very densely packed styles and subtylostyles arranged in a plumose architecture, microscleres of possibly aster-type, and a microgranular to fibrous secondary calcareous skeleton. The primary mineralogy of the calcareous skeleton was probably high-Mg calcitic. An assignment to the demosponge Order Axinellida is proposed.     

Belowground rhizomes and roots in waterlogged paleosols: Examples from the Middle Jurassic of Beijing,China

Plant rhizomes and roots occur in terrestrial ecosystems since at least the Devonian, but the documentation of belowground plant tissues is sparse in the fossil record. In this study, fossils representing belowground rhizomes and roots are described from the top of the Upper Yaopo Formation (Middle Jurassic), at the Yuejiapo section, Mentougou District, Beijing, China. Morphological studies of the plant fossils, together with lithofacies analyses, provide new information on plant–soil interactions during the Jurassic period. Three types of rooting systems are recognized from two fossiliferous beds. The Bed-1 Flora is interpreted as representing a Cladophlebis-dominated community, where abundant foliage remains mainly of Cladophlebis cf. scariosa and Cladophlebis delicatula are associated with Type-A rooting system. The Bed-2 Flora includes Type-B and Type-C rooting systems, although the floristic composition is unknown due to the absence of identifiable foliage remains. The Type-A and Type-B rooting systems consist of abundant in situ vertical rhizomes, fine shoot-borne roots and lateral roots, and are consistent with those of some extant ferns. The Type-C rooting system shows a thick central taproot and at least three orders of lateral roots, an architecture typical of various gymnosperms. The in situ rooting systems, as well as sedimentary evidence, contribute to the recognition of stacked, reworked Entisols in a dynamic waterlogged environment.     

Fertile organs and in situ spores of a new dipteridaceous fern Hausmannia sinensis from the Jurassic of northern China

As a representative fossil member of the dipteridaceous fern, genus Hausmannia was reported worldwide from the Mesozoic strata; however, little is known about the fertile structures, including sporangia and in situ spores, of this genus. In this study, a new species Hausmannia sinensis was identified from the Middle Jurassic of Nei Mongol (Inner Mongolia), northern China. The specimens are compressions and are well preserved with details of sporangia and in situ spores. The leaf laminae are broadly fan-shaped, with an almost entire margin. Primary and lateral veins dichotomously branch to form square or polygonal meshes. Each ultimate mesh bears one to two circular sori of 0.4 mm in diameter. Sori are exindusiate; each sorus contains three to six round to ovoid sporangia. The annulus is developed and oblique, with stomial region present in proximal position. Spores are trilete, circular to oval in shape. Both proximal and distal surfaces are covered with baculate to subverrucate sculptures. Spores range from 20 to 30 μm in diameter (average 28 μm), and are comparable to the dispersed genera Baculatisporites Thomas and Pflug and Apiculatisporis Potonié and Kremp. Hausmannia sinensis represents the first compression species of genus Hausmannia form Eurasia, which shows the combination of well-preserved sori, sporangia, annuli and in situ spore characters, and is therefore helpful for further understanding the diversity and evolution of the Dipteridaceae fern lineage through time.     

A new lasiosynid beetle from the Middle Jurassic of China with remarks on the systematic position of Lasiosynidae

A new beetle species, Lasiosyne laxa n. sp., is described from the Jurassic Daohugou deposits in Inner Mongolia, China. Its morphological significance and systematic position within the genus Lasiosyne Kirejtshuk et al., 2010a, Kirejtshuk et al., 2010b and the family Lasiosynidae are discussed. The research history of Lasiosynidae is summarized for the first time. The affiliation of Lasiosynidae to the superfamily Byrrhoidea is discussed in detail.