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A new genus and species of Baleyopterygidae, Aristoleuctra yehae gen. and sp. nov. collected from the Middle Jurassic of Daohugou Village, Shantou Township, Ningcheng County, Inner Mongolia, China, is described and illustrated. This is the first report of Baleyopterygidae from China. With the establishment of Aristoleuctra, Baissoleuctra conspecta Sinitshenkova, 1992 from Late Jurassic - Early Cretaceous of East Siberia is transferred to this genus.
Eoiocossus validas gen. and sp. nov., a new genus and species belonging to Palaeontinidae (Insecta, Hemiptera), is described from the Middle Jurassic of Daohugou, Inner Mongolia, China. It differs from other genera as follows: large forewing with small clavus, Sc terminating in costal margin beyond the nodus, nodal line along m₄ -cua partly, CuA₂ with two branches and A₂ developed. The ripple-like posterior margin and fresh colour pattern of Eoiocossus may be sex characteristics. The marginal membrane and ambient vein have not distinct evolutionary implications for the Palaeontinidae.
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The Galinha tracksite reveals a sequence of Bajocian–Bathonian limestones belonging to the Serra de Aire Formation (West−Central Portugal) and is one of the few sites in the world where Middle Jurassic sauropod dinosaur tracks can be found. This tracksite is characterised by the presence of long, wide gauge sauropod trackways, the Middle Jurassic age of which suggests these dinosaurs were more widely distributed over time than previously thought. Two trackways contain unique pes and manus prints with morphologies that allow a new sauropod ichnotaxon to be described: Polyonyx gomesi igen. et isp. nov. On the basis of different manus/pes prints and trackway features, the proposal is made to subdivide Sauropodomorpha ichno−morphotypes into five groups: Tetrasauropus−like, Otozoum−like, Breviparopus/Parabrontopodus−like; Brontopodus−like, and Polyonyx−like. Polyonyx gomesi igen. et isp. nov. is thought to represent a nonneosauropod eusauropod, with a well developed manus digit I. The posterior orientation of this digit print suggests they were made by a eusauropod dinosaur with a posteriorly rotated pollex. The manus print morphologies observed in two trackways suggest a stage of manus structure intermediate between the primitive non−tubular sauropod manus and the tubular metacarpal arrangement characteristic of more derived sauropods. The low heteropody (manus:pes area ratio 1:2) of the trackway renders it possible they could have been made by eusauropods such as Turiasaurus riodevensis, which has a similar manus:pes area ratio. The Polyonyx igen. nov. trackway was made by non−neosauropod eusauropod, and suggests that wide gauge sauropod trackways were not exclusively made by Titanosauriformes.
Paradermestes jurassiens gen. et sp. nov., a new dermestid beetle is described based on a well-preserved impression fossil collected from the Middle Jurassic Jiulongshan Formation in Daohugou Village, Shantou Township, Ningcheng County, Inner Mongolia, China, making it the oldest fossil of the family. Based on its size, no visible ocellus and laterally reduced hind coxal plates Paradermestes is placed in subfamily Dermestinae and tribe Paradermestini, trib. nov.
We describe a nearly complete mammalian femur from the Middle Jurassic (upper Bathonian) from Peski quarry, situated some 100 km south east of Moscow, central Russia. It is similar to the femora of Morganucodontidae in having a globular femoral head, separated from the greater trochanter and reflected dorsally, fovea capitis present, both trochanters triangular and located on the same plane, distal end flat, mediolaterally expanded, and somewhat bent ventrally, and in the shape and proportions of distal condyles. It is referred to as Morganucodontidae gen. et sp. indet. It is the first representative of this group of mammals in Eastern Europe from the third Mesozoic mammal locality discovered in Russia. Exquisite preservation of the bone surface allowed us to reconstruct partial hind limb musculature. We reconstruct m. iliopsoas as inserting on the ridge, which starts at the lesser trochanter and extends along the medial femoral margin for more than half of the femur length. On this basis we conclude that the mode of locomotion of the Peski morganucodontid was similar to that of modern echidnas. During the propulsive phase the femur did not retract and the step elongation was provided by pronation of the femur.
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Earliest laurasian sauropod eggshells

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Megaloolithid eggshells, known from many Cretaceous deposits since 19th century, are now recognized as remnants of sauropod dinosaurs. Our paper reports the discovery of megaloolithid egg remains from the Middle Jurassic (Bajocian) of the Quercy area (southwestern France). The new Jurassic ootaxon differs from related Cretaceous oospecies in having unusually thin shells. Even Megaloolithus aureliensis, the thinnest Cretaceous megaloolithid from France is three times thicker than the Jurassic eggshells. The cladistic analysis of ootaxa reveals a peculiar point in contradiction with the phylogenetic results based on skeletal remains: the Megaloolithidae belonged to sauropod dinosaurs, which appear to be the sister group of the hadrosaur eggs (Spheroolithidae oofamilly). This result could indicate a significant amount of homoplasy in the evolution of eggshell structures, depending strongly on the incubation environment (particularly for some characters as ornamentation, pore openings and pore canals), the reproductive physiology and the oviduct function. The Bajocian eggshells might represent the earliest offshoot of the Megaloolithidae oofamily and represent the earliest sauropod eggshell record known from the deposits of Laurasia supercontinent.
A new bark-gnawing beetle genus Sinopeltis gen. nov., with two species (S. jurrasica sp. nov. (type species) and Sinopeltis amoena sp. nov.), is described based on two well-preserved impression fossils. Specimens were collected from the Middle Jurassic Jiulongshan Formation in Daohugou Village, Shantou Township, Ningcheng County, Inner Mongolia, China from a lacustrine paleoenvironment, making it the oldest fossil of the family. Sinopeltis is placed into Peltinae incertae sedis.
A new species, Nannotanyderus kubekovensis, belonging to Tanyderidae (Diptera, Nematocera) from the Middle Jurassic of Siberia (Russia) is described and figured. Three hitherto known species of the genus Nannotanyderus Ansorge, 1994 are compared.
A new genus with two new species and one new species of fossil elaterids are described: Paradesmatus baiae sp. nov., Paradesmatus ponomarenkoi sp. nov., Protagrypnus robustus sp. nov. These findings document the fossils from the Middle Jurassic Jiulongshan Formation of Eastern Inner Mongolia, China. Fossil elaterids of Mesozoic with large triangular plates of metacoxae have been discovered only from the Upper Jurassic strata of Karatau so far, Paradesmatus baiae with the unique feature will expand our knowledge on the early diversification of elaterids.
Sinopachymeridium popovi, a new genus and species of fossil true bugs is described. The new species is reported from the Jiulongshan Formation (Middle Jurassic), in Daohugou Village, Shantou Town, Ningcheng County, Inner Mongolia, China. It clearly belongs to Pachymeridiidae by Sc, R and M diverging at a single point and presence costal fracture. The new genus is most similar to Pachycoridium Popov, 1986, but can be distinguished from the latter by the larger body, rostrum extending to second abdominal sternite, first vein of membrane situated remote from anterior margin of fore wing and fourth and fifth veins forming a merged vein.
Bulk sampling of a number of different marine and marginal marine lithofacies in the British Bathonian has allowed us to assess the palaeoenvironmental distribution of crinoids for the first time. Although remains are largely fragmentary, many species have been identified by comparison with articulated specimens from elsewhere, whilst the large and unbiased sample sizes allowed assessment of relative proportions of different taxa. Results indicate that distribution of crinoids well corresponds to particular facies. Ossicles of Chariocrinus and Balanocrinus dominate in deeper−water and lower−energy facies, with the former extending further into shallower−water facies than the latter. Isocrinus dominates in shallower water carbonate facies, accompanied by rarer comatulids, and was also present in the more marine parts of lagoons. Pentacrinitesremains are abundant in very high−energy oolite shoal lithofacies. The presence of millericrinids within one, partly allochthonous lithofacies suggests the presence of an otherwise unknown hard substrate from which they have been transported. These results are compared to crinoid assemblages from other Mesozoic localities, and it is evident that the same morphological adaptations are present within crinoids from similar lithofacies throughout the Jurassic and Early Cretaceous.
Many sauropod ghost lineages cross the Middle Jurassic, indicating a time interval that requires increased sampling. A wide taxonomic spectrum of sauropodomorphs is known from the Middle Jurassic of China, but the braincase of a new sauropod, named here Nebulasaurus taito gen. et sp. nov., is distinct. Nebulasaurus is sister taxon to Spinophorosaurus from the Middle Jurassic of Africa and represents a clade of basal eusauropods previously unknown from Asia. The revised faunal list indicates dramatic transitions in sauropodomorph faunas from the Jurassic to Cretaceous of Asia; these are consistent with geographic isolation of Asia through the Late Jurassic. Non-sauropod sauropodomorphs, non-mamenchisaurid eusauropods (including basal macronarians), and mamenchisaurids successively replaced previous grades through the Jurassic, and titanosauriforms excluded all other sauropod lineages across the Jurassic–Cretaceous boundary.
One new genus including two new species of fossil cupedids assigned to family Cupedidae, Gracilicupes crassicruralis gen. and sp. nov. and Gracilicupes tenuicruralis gen. and sp. nov., is described from the Middle Jurassic Jiulongshan Formation of eastern Inner Mongolia, China.
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