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Sixty two species of sponges, belonging to the Tetraxonia, of this number, 19 new ones: Brochodora latiramea n .sp., Pachypoterion biedai n.sp., Homalodora skrainivensis n.sp., H. polonica n.sp., H. brachiramosa n.sp., Heterostinia phytoniformis n.sp., Heloraphinia chordata n.sp., Phymatella irregularis n.sp., Thecosiphonia gracilis n.sp., Kozlowskispongia bulbosa n.gen., n.sp., Phyllodermia magna n.sp., Ph. pulchra n.sp., Eustrobilus extraneus n.sp., Ragadinia foraminifera n.sp., Plinthosella elegans n.sp., Acrochordonia regularis n.sp. and A. bifurcata n.sp. are described and one new genus, Kozlowskispongia n.gen., is erected. The species investigated belong to Tetractinellida (2 species), Tetracladina (32 species), Megacladina (16 species) and Dicranocladina (7 species). In most species, the morphology of the body, the structure of the skeleton and the morphology of the megascleres have been studied. In many of them, the microscleres have been found.
Buginbaatar transaltaiensis n.gen., n.sp., assigned tentatively to the Cimolomyidae (Marsh), is described from an incomplete skull from the uppermost Cretaceous (?Maastrichtian) of Khaichin Ula, Bugin Cav Region, trans-Altaian Gobi, Mongolian People's Republic. The geological profile, in which the specimen was found, is characterized. The systematic position of Buginbaatar n.gen. within the suborder Taeniolabidoidea is discussed and it is shown that in some respects it is intermediate between the Cretaceous Cimolomyidae and Eucosmodontidae.
Specimens of the belemnitellid Praeactinocamax Naidin, 1964 are described from the Upper Cretaceous of NW Siberia (Taimyr Region, Lower Agapa River, Russia). The rostra determined as Praeactinocamax aff. plenus consist of an aragonitic anterior part and a calcitic posterior part with a sharp boundary in between. This boundary surface is referred to as the “alveolar fracture”, and it is a typical morphological feature of early belemnitellids and not a result of diagenetic processes. The occurrence of Praeactinocamax in Arctic areas shows a wider palaeobiogeographical distribution of the genus in the Late Cenomanian–Early Turonian interval than previously known. This finding suggests that migration of the late Cenomanian–early Turonian fauna occurred across Turgai channel. The geographic position of these new records may also explain the occurrence of Praeactinocamax in the Turonian of the US Western Interior Seaway, the origin of which has been hitherto unclear.
The albanerpetontid fossil record in Asia was limited to five dentaries of unidentified genus from the Upper Cretaceous Khodzhakul (lower Cenomanian) and Bissekty (Turonian) formations, Kyzylkum Desert, Uzbekistan. Here I describe two fragmentary frontals from the Khodzhakul local fauna as the first unequivocal record of the genusAlbanerpeton in Asia.
Sont décrits les microorganismes des s édiment s marins du Crétacé supérteur de Pologne appartenant aux groupes suivants: Coccolithophoridés, Dinoflagellés, Hystrichosphaeridés et microorganismes in certae sedis. 14 espèces représentent les Coocolithophoridés, dont 4 considérées comme nouvelles (Zygolithus chelmiensis n.sp., Discolithus bugensis n.sp., D.polygonatus n.sp., D.reticulatus n.sp.). Les Dinoflagellés appartiennent à 9 espèces, dont 2 nouvelles (Lejeunia kozlowskii n.sp. et Leiofusa lidiae n.sp.). Sur 21 espèces des Hystrichosphaeridés, une est nouvelle (Pterospermopsis barbarae n.sp.). Des deux espèces de microorganismes de position systématique incertaine, une est nouvelle (Palambages deflandrei n.sp.). Une liste est donnée des localités et étages d'où proviennent les matériaux étudiés.
Twelve species of pelecypods representing the subfamilies: Pycnodonteinae, Exogyrinae and Ostreinae are described. The growth changes in Pycnodonte (Phygraea) vesicularis and in Gryphaeostrea vomer are reported. The "fingerprint shell structure"', has been found on the shell of. P. (Phygraea) vesicularis, and it is interpretrd as the remain of conchiolihe membrane in the subnacreous layer. In earlier stages of the Upper Cretaceous in, the Middle Vistula region the ostreids dominate, while in the later ones brachiopods and belemnites are more aboundant.
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The new aeshnopteran family Enigmaeshnidae is proposed for Enigmaeshna deprei gen. et sp. nov., the first fossil insect collected as imprint in the Earliest Cenomanian clay of the Puy−Puy quarry at Tonnay−Charente (Charente−Maritime, SW France). The bed bearing E. deprei was previously known for its highly diversified fossil plant assemblage. Although this taxon belongs to the much derived clade Aeshnodea, it is characterized by several unique hind wing venation characters, never found in other Aeshnoptera, viz. part of MAb distal of the trigonal planate very long, and presence of five posterior branches of AA directed towards posterior wing margin.
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Upper Cretaceous amniotic eggs from Gobi Desert

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There are described several types of Upper Cretaceous fossil amniote eggs, clutches and eggshells, collected during the Polish-Mongolian Paleontological Expeditions (1963—1971) in several localities of the Gobi Desert. Isotopic ratios of C and О are reported and discussed. The eggs may be attributed to saurischian and ornithischian dinosaurs, and palaeognathous birds. Four types of problematica are also described. Taphonomy and restoration of eggshells’ diffusive properties as compared with modern hard-shelled eggs suggest paleoecological interpretation of the nesting conditions as rather dry for smooth-shelled eggs, humid for ornamented eggs, and very humid for the thickest-shelled eggs. Different nest types are postulated for ornamented and smooth eggs, based on taphonomy and shell parameters.
The first unambiguous evidence of the presence of osteoderms in sauropod dinosaurs came from the discovery of Saltasaurus loricatus, a titanosaur from the Upper Cretaceous of Argentina. The dermal armor of Saltasaurus is composed of bony plates and small dermal ossicles. Here, we analyze the bone microstructure of these elements and provide information regarding its origin and development. The bony plates are composed almost entirely of reconstructed cancellous bone. Remains of primary bone consist of coarse bundles of mineralized collagenous fibers towards the external surface. Also, woven fibered bone tissue appears in the basal and lateral regions. Dermal ossicles lack secondary remodeling, and their matrix is formed by three orthogonal systems of collagenous fiber bundles. Growth lines are present in both bony plates and ossicles. Bone histology reveals that osteoderms mainly originated through direct mineralization (metaplasia) of the dermis, although other mechanisms are also involved (at least in the origin of dermal plates). The common features of development and integumental location of the osteoderms of Saltasaurus and other non−related vertebrates (e.g., lepidosaurs, crocodylomorphs) are linked to the intrinsic skeletogenic properties of the dermis.
New material of an ornithomimid from the Late Cretaceous deposits of Tsagan Khushu (Gobi Desert, Mongolia) is described. The material includes a partial axial skeleton, and hind and forelimb elements. The specimen is similar to Anserimimus planinychus from nearby Bugin Tsav locality in having ventrally flat, long, almost straight manual unguals. The new specimen differs from A. planinychus in the length of the penultimate manual phalanx II−2, which is only slightly shorter than Ph III−3, in a considerably lesser alae of the manual unguals, and in the height/width ratio of the proximal articular surfaces. The material suggests presence of third, hitherto unknown ornithomimid from the Nemegt Formation.
A new genus of Thanerocleridae, Archaeozenodosus bellus Yu and Kolibac gen. et sp. nov., is described and illustrated from the Upper Cretaceous (Cenomanian, ca. 99 Ma) amber near the Hukawng Valley of northern Myanmar, making it the first Mesozoic record of the family. Morphological characters preserved in the Burmese amber highlight the diversity of thaneroclerids during the Late Mesozoic and provide data for future phylogenetic studies of Thanerocleridae.
This paper describes a new nanhsiungchelyid turtle, Kharakhutulia kalandadzei gen. et sp. nov., based on two partial shells and additional shell fragments from the lower part of the Bainshire Formation (Upper Cretaceous, Cenomanian–lower Turonian) of the Khara Khutul locality of Eastern Mongolia. Our phylogenetic analysis places Kharakhutulia kalandadzei as the most basal member of the Nanhsiungchelyidae and suggests new relationships within this group. Previously reported nanhsiungchelyid specimens from the Khara Khutul are reassigned to Nanhsiungchelyidae indet. and Hanbogdemyssp. indet. Thus the Khara Khutul includes at least two valid taxa of nanhsiungchelyids. Our analysis of the nanhsiungchelyid record in Asia shows that other localities have only a single representative of this clade, making Khara Khutul a unique site. The basal phylogenetic position of Kharakhutulia kalandadzei emphasizes the importance of the study of this and other Cenomanian–Turonian localities of Asia to better understand the basal diversification of the Nanhsiungchelyidae.
Cervical vertebrae of azhdarchid pterosaurs were discovered in two Upper Cretaceous (Baynshire Suite) dinosaur localities, Bayshin Tsav and Burkhant, in the Gobi Desert. These are the first discoveries of pterosaur remains in the Upper Cretaceous of Mongolia. The Burkhant specimen includes a nearly complete atlas−axis complex, which has rarely been described in this clade of pterosaurs. Although all elements comprising this complex are fused together, a wing−like atlas neural arch is still discernable. The postzygapophyseal facet of the axis is long anteroposteriorly and convex dorsally, and would likely have allowed a fairly large range of dorsoventral flexion at the axis−third cervical joint unlike in other well−known ornithocheiroids such as Pteranodon and Anhanguera. Both Mongolian localities represent inland, terrestrial environments, which were apparently not typical habitats of pterosaurs, thus adding further evidence for the ubiquity of Azhdarchidae during the Late Cretaceous.
The Campanian (Upper Cretaceous) seep carbonate at Omagari (Hokkaido, Japan) yields a monospecific association of the terebratulide brachiopod Eucalathis methanophila Bitner sp. nov. The association is the only occurrence of brachiopods known from the post−Early Cretaceous history of chemosynthesis−based communities. Unlike many earlier rhynchonellide−dominated hydrocarbon seep associations—which disappeared in Aptian times—this association is composed of chlidonophorid terebratulides. It is hypothesised here that large rhynchonellide brachiopods have been outcompeted from chemosynthesis−based associations by large chemosymbiotic bivalves (especially lucinids) and that this seep association containing numerous terebratulide brachiopods originated as a result of immigration from the background fauna settling in a seep that lacked numerous large bivalves but offered some hard substrates for brachiopod attachment. Some living chlidonophorids are known to settle around seep/vent localities or more generally in deep−water hard−substrate settings. We review occurrences of brachiopods in chemosynthesis−based associations and show that brachiopods immigrated repeatedly to seep/vent environments. Eucalathis methanophila Bitner sp. nov. represents the oldest and single Mesozoic record of the genus. The new species is similar in ornamentation to three living species, Indo−Pacific E. murrayi, eastern Atlantic E. tuberata, and Caribbean E. cubensis but differs in having a higher beak and wider loop. Additionally the studied species is nearly twice as large as E. tuberata.
A new sauropod titanosaur from the Upper Cretaceous Anacleto Formation is described. Narambuenatitan palomoi gen. et sp. nov., is diagnosed by cranial and axial autapomorphies. The holotype, which represent a subadult individual, consists of the left premaxilla and maxilla, braincase, both quadrates, one cervical vertebrae, one dorsal vertebra, fragments of cervical and dorsal ribs, seventeen caudal vertebrae, caudal transverse processes, fragments of haemal arches, left sternal plate, right coracoid, left humerus, left ulnae, both pubes, iliac pedicel, proximal fragment of right ischia, and an incomplete left femur. The phylogenetic analysis indicates that Narambuenatitan is a non−eutitanosaurian lithostrotian, and that it shares with Epachthosaurus a neural spine in middle caudal vertebrae which are laminar and posteriorly elongated.
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