Radiometric Dating of Ignimbrite from Inner Mongolia Provides no Indication of a Post-Middle Jurassic Age for the Daohugou Beds

Lacustrine deposits exposed at Daohugou, Inner Mongolia, China, have yielded superbly preserved vertebrate fossils. The fossil beds were first misinterpreted as of Early Cretaceous age, based on alleged occurrences of key fossils of the Jehol Biota. Compelling evidence revealed by more rigorous research involving regional biostratigraphy, radiometric dating, and paleontology supports the Middle Jurassic age of the fossil beds. Despite the awesome evidence for the Middle Jurassic age of the Daohugou beds, the age dispute has been resurrected recently by invoking an overturned stratigraphic sequence. A careful review of the data, however, found no evidence that this sequence has been overturned. In addition, many of the assumptions, on which the conjecture of the fossil beds being post- Middle Jurassic is imprudently based, are self-contradictory or otherwise misleading. Thus, the post- Middle Jurassic age of the Daohugou beds as an unfounded conclusion can readily be dismissed.

Early Evolution of Apocrita (Insecta,Hymenoptera) as Indicated by New Findings in the Middle Jurassic of Daohugou,Northeast China

The classification and phylogeny of the basal Vespina （= Orussoidea ＋ Apocrita） are reconsidered based primarily on rich and well preserved material from the Middle Jurassic of Daohugou in Inner Mongolia, China. Comparatively smooth morphological transitions are traced from a Xiphydriidae-like ancestor toward Orussoidea via the Jurassic family Karatavitidae, and through Karatavitidae and the Jurassic and Early Cretaceous family Ephialtitidae independently to Stephanidae, to Evanioidea, and, via the extinct Jurassic Kuafuidae fam. nov. to the remaining Apocrita. New hypothesis is proposed concerning development of the characteristic wasp-waist of Apocrita, which is supposed to appear independently and in different ways in Evanioidea and in the rest of Apocrita. As a result, six infraorders are proposed for the suborder Vespina with the following taxonomic structure： infraorder Orussomorpha including the only superfamily Orussoidea （Karatavitidae ＋ Paroryssidae ＋ Orussidae）, infraorder Stephanomorpha with the only superfamily Stephanoidea （Ephialtitidae ＋ Stephanidae）, infraorder Evaniomorpha with the only superfamily Evanioidea of traditional composition, infraorder Ceraphronomorpha with the superfamih＇es Ceraphronoidea s. str. and monotypical Megalyroidea and Trigonaloidea, and the infraorders Proctotrupomorpha, Ichneumonomorpha, and Vespomorpha of traditional composition. The family Kuafuidae is unplaced to infraorder because it is putatively paraphyletic with respect to Ceraphronomorpha, Proctotrupomorpha, Ichneumonomorpha and Vespomorpha. Described as new are Karatavites junfengi sp. nov, Praeratavites wuhuaensis sp. nov., P. perspicuus sp. nov, Postxiphydria daohugouensis gen. et sp. nov., P. ningchengensis gen. et sp. nov., Postxiphydroides strenuus gen. et sp. nov., Praeratavitoides amabilis gen. et sp. nov., Proapocritus densipediculus sp. nov., P. sculptus sp. nov., P. longantennatus sp. nov., P. formosus sp. nov., P. atropus sp. nov., P. elegans sp. nov., Stephanogaster pristinus sp. nov., Asiephialtites lini sp. nov., Praeproapocritus vulgatus gen. et sp. nov., Sinaulacogastrinus solidus gen. et sp. nov., Sinevania speciosa gen. et sp. nov., Eonevania robusta gen. et sp. nov., Kuafua polyneura gen. et sp. nov. （all from the Middle Jurassic of Daohugou）, as wall as Kuafuidae fam. nov. including Kuafua gen. nov. as wall as Arthrogaster Rasnitsyn, 1975, and Leptogastrella Rasnitsyn, 1975 from the Upper Jurassic of Karatau in Kazakhstan.

A New Darwinopterid Pterosaur from the Middle Jurassic of Western Liaoning,Northeastern China and its Ecological Implications

A new species of Darwinopterus,D.robustodens sp.nov.is described and named.Based on the new specimen,the diagnostic characters of Darwinopterus are amended and include：rostral dentition composed of well-spaced,spike-like teeth;the longest teeth are confined to the anterior half of the tooth row;tooth alveoli have raised margins;nasoantorbital fenestra confluent;inclined quadrate;elongate cervical vertebrae with low neural spine and reduced or absent ribs;long tail of more than 20 caudals partially enclosed by filiform extensions of the pre-and postzygapophyses;short metacarpus less than 60 per cent length of humerus,fifth toe with two elongate phalanges and curved second pedal phalanx of the fifth toe with the angle between the proximal and distal segments about 130 degrees.The complete specimen of the new pterosaur D.robustodens sp.nov.provides much more osteological information.The differences in tooth morphologies between Darwinopterus modularis and D.robustodens sp.nov.suggest that they filled different ecological niches.The hard integument-bearing Coleoptera may have been the main food source of Darwinopterus robustodens.

A New Species of Phoenicopsis Subgenus Windwardia(Florin) Samylina(Czekanowskiales) from the Middle Jurassic of Inner Mongolia, China

A new species of Phoenicopsis subgenus Windwardia （Florin） Samylina, Phoenicopsis neimengguensis sp.nov., is recognized from the Middle Jurassic Zhaogou Formation in the Shiguai Basin, a Jurassic coal-bearing sedimentary basin in Inner Mongolia, China. Linear leaves are in bundles of six to eight and are attached on a short shoot. The leaf is amphistomatic with one or two irregular rows of longitudinally oriented stomata in each intercostal zone on the upper epidermis and three or four （occasionally six） rows of stomata in each intercostal zone on the lower epidermis. Each stomata is surrounded by four to six subsidiary cells with unevenly developed papillae. The anticlinal walls of epidermal cells are straight. Cuticular thickenings or papillae are present on the outer surface of the periclinal walls. This is the first time that Phoenicopsis subgenus Windwardia （Florin） Samylina is recognized from the Middle Jurassic of Inner Mongolia, China. The occurrence of the new species is noteworthy because it extends the geological and geographic distribution of Phoenicopsis subg. Windwardia in China and Eurasia. The discovery is significant as it increases our knowledge of Phoenicopsis subg. Windwardia by providing new data on morphological and epidermal features.

A New Family of Moths from the Middle Jurassic(Insecta:Lepidoptera)

Three lepidopteran species, from the Middle Jurassic Daohugou beds （inner Mongolia, China）, are described in a new family, Mesokristenseniidae, and new genus, Mesokristensenia, which could represent the sister group of the Micropterigidae. Mesokristensenia differs from all extant Lepidoptera, but one genus （Agathiphaga, Agathiphagidae）, in retaining four median veins in the forewing, a plesiomorphy also present in many Trichoptera. Evidence for placing Mesokristensenia in the Lepidoptera includes four traits, notably a previously unrecorded autapomorphy of this insect order： beyond stem Ml＋2, vein M1 is bent and connected to cross-vein r-m （in both wing pairs）. Among 24 characters taken into account to assess the systematic position of Mesokristensenia, 12 are considered informative for a cladistic analysis involving this fossil taxon and the four suborders recognized in present-day Lepidoptera （Zeugloptera, Aglossata, Heterobathmiina, and Glossata）.

Geological and geochemical characteristics of Middle Jurassic granites in Bengbu uplift, Southeast of North China craton

1 Introduction The early formation and evolution of the North China craton has been widely concerned by scientists.The Bengbu uplift belt is located in the southeast of the craton,theresearch degree of the belt is relatively low and received increasing attention from many scholars in recent years.Through the author’s practical work and combined with

Cuticles and Spores in Situ of Coniopteris hymenophylloides from the Middle Jurassic in Gansu, Northwestern China

Coniopteris was a ubiquitous plant of the Jurassic and Cretaceous periods and played an important role in the flora of the time. However, its anatomical structure is relatively poorly known. The specimens of Coniopteris hymenophylloides(Brongniart) Seward described here were collected from the Yaojie Formation in Gansu Province, northwestern China. The sterile fronds are characterized as being at least bipinnate with alternate arranged linear pinnae covered by thin cuticles. Fertile fronds are linear-lanceolate, with single sorus at the margin of each fertile pinnule. In situ spores are typically trilete, triangle to subcircular in polar view, cap-shaped in equatorial view, and 37 μm in average diameter. The trilete marking is straight and narrow, generally extends to 4/5 of the spore radius. The spore surface is smooth, and parts of the exine are granulated. The epidermal cells of cuticles are irregular in shape, approximately 40-60μm long and 10-20 μm wide. The elliptical stomatal complexes are paracytic,approximately 30 μm long and 19 μm wide,and irregularly distributed. On the basis of its epidermal structures and comparisons with extant ferns, we consider that Coniopteris displays combined features of the related extant genera.

A New Species of Liadotaulius(Insecta:Trichoptera) from the Middle Jurassic of Daohugou,Inner Mongolia

Diverse caddis flies are recently collected from the Middle Jurassic Daohugou fauna in Ningcheng County, Inner Mongolia, northern China, and different types of caddis cases have been reported in the same locality. A new species of caddisfly, Liadotaulius daohugouensis sp. nov. is described and illustrated; the establishment is based on a well-preserved isolated forewing collected from the Middle Jurassic Jiulongshan Formation of Daohugou. The family status of Liadotaulius is discussed on the basis of new material and is referred to the family Philopotamidae. The Daohugou fauna continues to provide new data for studying the early evolution of Trichoptera.

New Isophlebioid Dragonflies from the Middle Jurassic of Inner Mongolia,China(Insecta:Odonata:Isophlebioptera:Campterophiebiidae)

Three new species of fossil dragonflies assigned to Sinokaratawia Nel, Huang and Lin in family Campterophlebiidae, i.e.S, daohugouica sp. nov., S. magica sp. nov. and S. gloriosa sp. nov., and new materials of male S. prokopi Nel, Huang and Lin, 2007 are described from the Middle Jurassic of Daohugou, Inner Mongolia, China. An emended diagnosis of genus Sinokaratawia was proposed.

New Fossils of Eoptychopteridae (Diptera) from the Middle Jurassic of Northeastern China

Three new species of the extinct genus of Eoptychopterina from the Eoptychopteridae family, Eoptychopterina antica sp. nov., Eoptychopterina adnexa sp. nov., and Eoptychopterina mediata sp. nov., are described and illustrated. These three new species are established based on fossil specimens with bodies and complete wings. All were collected from the Middle Jurassic Jiulongshan Formation of Daohugou in eastern Inner Mongolia, China. Based on the new materials, the name of two species in Eoptychopterina from China-Eoptychopterina elenae Ren and Krzeminski and Eoptychopterina gigantea Zbang-is sysnonymum junius.

The Insect Oviposition Firstly Discovered on the Middle Jurassic Ginkgoales Leaf from Inner Mongolia, China

Although the evidence of insect oviposition on plant organs has been reported from the late Paleozoic to the Miocene, record from the middle Jurassic is still blank. This paper reports a significant evidence of insect oviposition on plant leaf from the middle Jurassic for the first time. The ovipositional scar is distributed on the abaxial surface of Sphenobaiera leaf（Ginkgoales） from the middle Jurassic Daohugou Formation of Inner Mongolia, China. A new ichnospecies Paleoovoidus venustus sp. nov. is described. The scar is elliptic to oval, arranged in longitudinal rows between leaf veins with almost regular distance, with its long axis paralleling to the leaf venation. This discovery adds new information to the morphology of insect endophytic oviposition probably produced by Odonata existed in a terrestrial ecosystem ~165 Ma ago. The new materials also provide important data for the study of insect reproductive biology, plant-insect interaction and coevolution, as well as understanding the paleoclimate and palaeoenvironment during that time in northeast China.

Discovery of a New Middle Jurassic Dinosaur Site in Sichuan,China

The Sichuan Basin,also known as the‘Red Basin’,is famous for its abundance of Mesozoic dinosaur fossils,especially in the Zigong area during the Jurassic era;the Middle Jurassic Shunosaurus and the Late Jurassic Mamenchisaurus faunal assemblages are the most representative.The Qinglongshan dinosaur fossil site is located in Fuxing,to the northwest of Rong County,Zigong City.This new site is situated within the Middle Jurassic Xiashaximiao Formation,and geologically is roughly equivalent to the well-known Dashanpu dinosaur fossil site.More than 600 dinosaur fossils were found concentrated in the excavation area,including teeth;cervical,dorsal and caudal vertebrae;and various parts of appendicular skeletons.This fossil site is also most significant as it provides new information on non-avian dinosaur life during the poorly understood Middle Jurassic.

A New Mamenchisaurid Dinosaur from the Middle Jurassic of Yuanmou,Yunnan Province, China

A new mamenchisaurid dinosaur, Eomamenchisaurus yuanmouensis gen et sp. nov. is erected based on an incomplete skeleton from the Zhanghe Formation, the Middle Jurassic of Yuanmou, Yunnan Province. The new taxon is characterized by absence of pleurocoels in dorsal vertebrae and the dorsal verterbrae with slightly convex anterior articular surfaces, moderately concave posterior articular surfaces; the fourth trochanter is developed posteromedially on the femur; length ratio of the tibia to the femur is approximately 0.64; and the shaft of the ischium is rod-like. Two fused centra of the posterior dorsal vertebrae （the presumed 9th and the 10th dorsal vertebrae） are similar to those in other mamenchisaurid dinosaurs, including Mamenchisaurus hochuanesis, M. youngi and Chuanjiesaurus anaensis. Therefore, fusion of centra of the ninth and the tenth dorsal vertebrae can be recognized as a synapomorphic character of the Mamenchisauridae.

A New Female Cone,Araucaria beipoiaoensis sp.nov.from the Middle Jurassic Tiaojishan Formation,Beipiao,Western Liaoning,China and Its Evolutionary Significance

A new species of Araucaria, Araucaria beipiaoensis sp. nov., collected from the Middle Jurassic Tiaojishan Formation, southern hill of Shebudai village, near Beipiao city, western Liaoning is based on a permineralized female cone, which is ovate to elliptical in shape, about 11 cm × 7 cm × 4.5 cm in size. The cone bears rhomboid bracts that are spirally attached, texture thicker, with wings on both sides, with a detached lamina-like apex at the tip. In inner structure the ovuliferous scales are thicker and fused with bracts at the end with a ligular sulcns. There is one wingless ovule/seed per seed-scale complex embedded in the ovuliferous scale tissue, with the micropyle directed toward the cone axis. The ovules/seeds are long ovate or elliptical in shape, 1 cm long and near the base about 3 mm in diameter; the ovule/seed integuments have begun differentiation into 3 layers： the sarcotesta, sclerotesta, and endotesta. The nucellus is free from the enclosing integuments except in the chalazal region where it is fused to the inner layer （endotesta） of integument. Some ovules show cellularized nucellar tissue. Mature seeds exhibit the papery-thin wavy nucellus characteristically near to the micropyle. The embryonic tissue appears to be four cotyledons. The morphology and structure of the cone shows a close relationship to the araucarian cones of fossil and living genera but differs from any known species. The new species is distributed in the Middle Jurassic of the northern hemisphere, especially Asia, and has important significance for the evolution of the Family Araucariaceae.

A New Theropod Dinosaur from the Middle Jurassic of Lufeng,Yunnan,China

A new theropod dinosaur, Shidaisaurusjinae gen. et sp. nov., has been described on the basis of an incomplete skeleton. The specimen was found near the base of the Upper Lufeng Formation （early Middle Jurassic） in Yunnan, China. It is the first theropod dinosaur from the Middle Jurassic of Yunnan. Shidaisaurus jinae is distinguishable from other Jurassic theropods by certain features from the braincase, axis, and pelvic girdle. The absence of any pleurocoels in the axis or in any anterior dorsal vertebrae suggests that the new Lufeng theropod is relatively primitive and more plesiomorphic than most of the Middle to Late Jurassic theropods from China. Most Chinese taxa of Jurassic theropod dinosaurs have not been well described; a further detailed study will be necessary for us to determine their phylogenetic relationships with Shidaisaurusjinae.

Repeated Wildfires in the Middle Jurassic Xishanyao Formation(Aalenian and Bajocian Ages) in Northwestern China

The coal-bearing strata in the southern Junggar Basin in northwestern China have recently attracted the attention of coal geologists. Its abundance of coal resources is of great interest as there is a potential of unlocking details about the palaeoclimatic information. Coal deposits have the capacity to record wildfire events, even those with inefficient combustions. To characterize wildfire events and palaeoclimatic history of the Middle Jurassic Xishanyao Formation(Aalenian and Bajocian ages), 22 coal samples from borehole cores and coal mines in the southern Junggar Basin were collected and their macerals were analyzed. The results indicated that fusinite and semi-fusinite were the dominant components of inertinite with proportions of 35.27% and 54.67%, respectively. The presence of inertinite is an indicator that wildfires occurred at the time of peat land development, and the widespread occurrence suggests large scale wildfires during the Middle Jurassic. This study proposes a new parameter for the evaluation of wildfire features by combining burning frequency and burning temperature. The comprehensive evaluation index(CEI) was influenced by the lacustrine basin level and ancient plant types from a sequence framework. During the Middle Jurassic, most wildfires were surface fires with low level and ground fire with high level. High oxygen levels were estimated in the lower, middle, and upper members of the Xishanyao Formation with corresponding to 26.78%, 24.55%, and 23.55%, respectively. The high oxygen levels would be the primary cause of repeated wildfires in the Middle Jurassic. These results are helpful for understanding palaeoclimatic changes in the Middle Jurassic.

New Discovery of Reproductive Organs and Spores in Situ of Ginkgoales and Czekanowskiales from the Middle Jurassic of Shaanxi, China

Objective Ginkgoales and Czekanowskiales are important components of Mesozoic flora and were widely distributed in the Northern Hemisphere. They are usually preserved together in the stratum. Their fossils are abundant in the Middle Jurassic of Shaanxi Province, but there are no reports on their reproductive organs. Here, we report two male gymnospermous pollen cones from the Middle Jttrassic Yan＇an Formation of the northeast Yulin City, Shaanxi Province, China. The characteristics of the fossils, including those of pollens, have been described in detail. The new specimens were compared with fossils closely similar in morphology, and the taxonomic affinity and systematies were established. The present results offer new fossil materials for the study of taxonomy, evolution, and phytogeography of Ginkgoales and Czekanowskiales.

A New Species of Ginkgo with Male Cones and Pollen Grains in situ from the Middle Jurassic of Eastern Xinjiang,China

Well-preserved Ginkgo pollen organs are analyzed from the Middle Jurassic Xishanyao Formation of the Turpan–Hami Basin, Xinjiang Uygur Autonomous Region, northwestern China, and are described as a new species, Ginkgo hamiensis Z.X. Wang et B.N. Sun sp. nov. The immature male cones are cylindrical and catkin-like, with two longitudinal stripes on the stalk. The pollen sacs are shaped like a long oval with two pollen sacs fused together for each microsporophyll, and the microsporophyll tip is a triangular cystidium. The pollen grains are oblong or fusiform and monocolpate; both ends are blunt or sharp. By comparison with previously reported fossil records of Ginkgo plants, we determined that the current fossils are different from all other reported species; thus, the present fossil is referred to as a new species of Ginkgo. The reproductive organs of the Ginkgo fossils described herein can provide valuable information for the study of Ginkgo plants. Further, there are two probable evolutionary trends in the Ginkgo pollen cones. One trend is that the number of pollen sacs changed from three or four during the Jurassic and Cretaceous to two at the present day; the other is that the number of pollen sacs has remained two from the Middle Jurassic to the present day. In addition, the pollen cones described herein are similar to the pollen cones of the extant Ginkgo, which strongly indicates that the morphology of Ginkgo plants may have remained highly conserved over millions of years.

Middle Jurassic—Tertiary Deposits and Ostracod—Charophyte fossil assemblages of Xining and Minhe Basins

The Xining and the Minhe Basins bordering on each other around Ledu innorthwestern China cover a wide area from the west of Lanzhou in Gansuprovince to the east of Xining in Qinghai province.In these inland basins,Meso-Cenozoic terrestrial deposits about 6000-7000 meters in thicknessand rich in mineral resources,such as coal,oi1 as well as salts,had beenaccumunated,which yield abundant organic remains comprising microfossils,such as nonmarine ostracods,charophytes,spores and pollen and macrofos-si1s including bivalves.gastropods,esthierians,fishes,reptiles and plants.

New material of Coniopteris simplex from the Middle Jurassic of the Ordos Basin,Inner Mongolia,China and implications on its spatio-temporal distribution and paleogeography

Coniopteris simplex is a common component in many Jurassic floras.However,due to morphological variations in sterile fronds and incomplete preservation of reproductive organs,its classification has been controversial for a long time.Here,we present new material collected from the Middle Jurassic Yan’an Formation in the Ordos Basin,Inner Mongolia.The new material reveals important morphological characters,including hemi-dimorphic fronds,two forms of sterile pinnae,short-stalked sori and sporangia on fertile fronds,annulus of sporangium composed of about 30 cells,in situ rounded triangular spores with protruded suture,and the lips of trilete laesura encircled by one or two rows of small ostioles.Based on these observations,we emended the diagnosis of this common species.The spatio-temporal distribution of Coniopteris simplex shows that the iconic species was restricted to the paleolatitudes ranging from 19.5°N to 48.9°N in the Northern Hemisphere during the Early—Late Jurassic,mainly distributed in the tropical to paratropical zones,and the paleolongitude ranging from 9.6°E to 129.3°E,which may be limited by the opening of the Viking Corridor and the splitting of the Central Atlantic Ocean.