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1.
A fructification with unusual branching arrangement, Perezlaria oaxacensis gen. et sp. nov., is described from the Middle Jurassic Zorrillo Formation of Oaxaca, Mexico. The sporangial heads are similar to the pollen-bearing organs of several Mesozoic pteridosperms. The association of P. oaxacensis, as well as some isolated organs resembling the synangia of Caytonanthus, with glossopteroid foliage is noted.  相似文献   

2.
In this paper the data on fossils of the family Cerophytidae are reviewed. New synonymy on generic names Necromera Martynov 1926 (proposed in composition of the family Oedemeridae); Idiomerus Dolin in Dolin et al. 1980, n. syn. (proposed in composition of Elateridae) and Leptocnemus Hong & Wang 1990, n. syn. (proposed without any family attribution) is established. New materials on this family from Mesozoic deposits of Asia are cited. As a result, it was established that this spreads in deposits of both Upper Jurassic and Lower Cretaceous. Mercata festira Lin 1986 described from Lower Jurassic as member of Silphidae and Abrotus reconditus Dolin in Dolin et al. 1980 described from Upper Jurassic as a member of Elateridae are transferred to Cerophytidae. Diagnoses of the genus Necromera and family Cerophytidae in compression fossils are elaborated. Necromera admiranda n. sp. is described from the Upper Jurassic-Lower Cretaceous in Liaoning, China. The historical development of the family from the Lower Jurassic is discussed.  相似文献   

3.
Small, gracile mostly tridactyl tracks from the Middle Jurassic of Henan Province represent the first example of the ichnogenus Anomoepus from this region. They represent a growing number of reports (at least eight) of this ichnogenus from the Jurassic of China. In conjunction with Changpeipus and Eubrontes, they appear characteristic of known global footprint biochrons. Anomoepus indicates the presence of ornithischian dinosaurs that are often scarce or unknown from skeletal remains in coeval deposits. When first discovered, these tracks were informally referred to as bird tracks. This interpretation reflects convergence between small Jurassic Anomoepus and avian theropod tracks that are hitherto known only from the Cretaceous and the Cenozoic. However, most Anomoepus are larger and more robust than any hitherto known Mesozoic avian tracks.  相似文献   

4.
Abstract A new genus and two new species of short-horned flies are described: Alleremonomus xingi gen. etsp. nov., Allwemononus liaoningensis gen. etsp. nov. They are assigned to the extinct family Ere-mochaetidae within the suborder Brachycera of Diptera. They were extracted from the Late Jurassic sediments of Beipiao City, Liaoning Province.  相似文献   

5.
Our studies indicate a Tertiary age for silicified palm roots and wood from near Redmond, Utah, recently described as the first unequivocal angiosperms from pre-Cretaceous strata. Field relationships and petrographic analysis demonstrate that the rocks in which the palm roots occur in place, supposedly beds of the Jurassic Arapien Shale, are actually strata of the Dipping Vat Formation of middle Tertiary age. The type and only localities of the palm woods designated as Palmoxylon pristina Tidwell and P. simperi Tidwell are on the Arapien Shale; however, unequivocal evidence that the specimens were in place is lacking. Both of these localities are situated on drainages topographically below an angularly unconformable Tertiary sequence including the Dipping Vat Formation. In the immediate area the Dipping Vat Formation contains abundant in situ palm wood and roots. Slump blocks of this sequence, some of them containing palm material, were found in the vicinity of both type localities. Sections of palm wood from the Dipping Vat Formation display the same anatomical features that characterize Palmoxylon pristina and P. simperi, including such characteristic attributes as the presence of fiber strands in the ground tissue. The probability that woods of P. pristina and P. simperi, rather than having originated in the Arapien Shale, were transported from the Dipping Vat Formation during post-Tertiary erosion makes a Jurassic age for these fossil angiosperms insupportable.  相似文献   

6.
Abstract: Fossil testate amoebae and their non‐marine finds are rare so their ecological importance through Earth history is poorly understood. The Lower Jurassic shallow water black‐shales of Trento Platform (north‐east Italy) are rich in micro‐organisms and contain a thecamoebian and ostracod assemblage representing the first known record of Early Jurassic oligohaline forms from the European mainland. The thecamoebians are represented by the genera Difflugia, Pontigulasia and Centropyxis. The present discovery of Lower Jurassic thecamoebians in fine carbonate organic‐rich deposits indicates, for the first time, that these sediments can preserve testate amoebae very well. The occurrence of difflugid testate amoebians confirm a transitional marine‐terrestrial habitat, outside large bodies of water, and suggests occasional eutrophication in ephemeral restricted aquatic environment in the Sinemurian–Pliensbachian Trento Platform.  相似文献   

7.
Cyathophora Michelin, 1843, hitherto well known from the Upper Jurassic and Cretaceous, has been found in the Middle Jurassic (Bajocian) of the Kachchh Basin, western India. Eleven specimens ofCyathophora bourgueti (Defrance, 1826) from the Babia Cliff Sandstone member of the Kaladongar Formation, exposed along the northern scarp of the Kala Dongar, Pachchham Island, Kachchh, are described and illustrated as the earliest Jurassic record of the family CyathophoridaeVaughan & Wells, 1943. It is suggested that the monospecific occurrence ofCyathophora bourgueti was controlled by salinity.   相似文献   

8.
Abstract Rudiaeschna limnobia gen. et sp. nov. (Aeshnidae), Liogomphus yixianensis gen. et sp. nov. (Gomphidae) and Mesocordulia boreala gen. et. sp. nov. (Corduliidae) are described and figured. All the specimens are recovered from the Upper Jurassic deposits of Beipiao City, Liaoning Province, China, and now housed in the Geological Museum of China, Beijing.  相似文献   

9.
Four adult and immature water boatmen from the Middle Jurassic and uppermost Middle Jurassic or lowermost Upper Jurassic Jiulongshan, Haifanggou and Daohugou formations in the northern and northeastern China are described as Yanliaocorixa chinensis (Lin, 1976), Jiulongshanocorixa genuina gen. et sp. nov., and Daohugocorixa vulcanica gen. et sp. nov., referred to the extinct subfamily Velocorixinae, and Karataviella popovi sp. nov., referred to the extant subfamily Diaprepocorinae. All the forms have previously been identified as one species, Yanliaocorixa chinensis. This species, found only in the Haifanggou Formation, is absent from the Jiulongshan Formation and other sites in China. The systematic position of corixids recorded earlier from the Mesozoic of China is reviewed and reassessed. Assemblages of dominant aquatic insects from various Jurassic nonmarine sedimentary basins in northern and northeastern China are described for the first time. They are entirely different between the Jiulongshan, Haifanggou, and Daohugou formations. The first formation is probably older than the other two.  相似文献   

10.
11.
Today, the genus Sutneria comprises 14 species, 12 of which have been found in the Submediterranean Upper Jurassic of southern Germany, representing in some cases important stratigraphic marker fossils. In southern Germany, Sutneria appears from the Upper Oxfordian to the Middle Tithonian. It is also represented in the Epicontinental and Sub-mediterranean Upper Jurassic of the Ardèche (southeastern France) and in the Celtiberic (northeastern Spain). But in the typical Mediterranean as well as in the typical Boreal ammonite faunas Sutneria has been unknown up until now. New findings show Sutneria platynota (Lowermost Kimeridgian) in an Ammonitico rosso facies of the Betic Jurassic in southeastern Spain and Sutneria cf. subeumela (Uppermost Lower Kimeridgian) in the stratotype section of the Volgian near Gorodishche, north of Ulyanovsk, USSR. The value of the species of Sutneria as index fossils has been established for areas outside Central Europe as well as for different facies. Como mínimo, doce de las catorce especies actualmente encuadradas en el género Sutneria han sido identificadas en el Jurásico superior de Alemania meridional; los fósiles característicos suministrados por esta formación permiten puntualizar que las especies de Sutneria se localizan en los pisos comprendidos entre el Oxfordiense superior y el Titoniense medio. Las facies epicontinentales y submediterráneas de estos pisos son identicas a las presentadas por el Jurásico superior del SE de Francia (Ardèche) y del NE de España (Cordillera Ibérica) donde tambien ha sido identificada la presencia de Sutneria. Sin embargo, venia siendo desconocida la asociación de este género con la fauna amonítica típicamente mediterránea y boreal hasta que nuevos y afortunados hallazgos han permitido descubrir Sutneria platynota en una facies de Ammonitico rosso correspondiente a la base del Kimeridgiense inferior de la Cordillera Bética (SE. de España) y Sutneria cf. subeumela hacia el techo de Kimeridgiense inferior en el perfil estratotípico del Volgiense cerca de Gorodishche, N. Ulyanovsk (U.R.S.S.); estos hallazgos en facies distintas y alejadas de las de Europa Central parecen evidenciar la significación cronoestratigráfica atribuible a las especies del género Sutneria  相似文献   

12.
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.  相似文献   

13.
Abstract: The sauropod dinosaur ‘Bothriospondylus’, originally named on the basis of Late Jurassic remains from England, is demonstrated to be invalid, and the characters used to diagnose it are shown to be obsolescent features which are widespread throughout Sauropoda. Material referred to this genus spans a temporal range from the Middle Jurassic until the early Late Cretaceous and has been described from five different countries, across three continents. These remains represent a wide array of sauropod groups, comprising non‐neosauropod eusauropods, a macronarian, titanosauriforms (including at least one definite brachiosaurid) and a rebbachisaurid. The type material of the Middle Jurassic ‘B. madagascariensis’ represents a derived non‐neosauropod eusauropod and possesses two potential autapomorphies. However, as a result of the fragmentary nature of the material and the uncertainty surrounding its association, a new taxon is not erected. Of the numerous specimens referred to ‘Bothriospondylus’, however, several remains are considered diagnostic: Ornithopsis hulkei (Early Cretaceous, UK), Lapparentosaurus madagascariensis (Middle Jurassic, Madagascar) and Nopcsaspondylus alarconensis (early Late Cretaceous, Argentina). At least three types of sauropod were present in the Bathonian (Middle Jurassic) of north‐west Madagascar, with a basal eusauropod (Archaeodontosaurus), a more derived eusauropod (‘B. madagascariensis’) and a titanosauriform (Lapparentosaurus) all approximately contemporaneous. Palaeocontinental reconstructions suggest that Middle Jurassic Madagascan sauropods would still have been capable of global biotic interchange, and this is perhaps reflected in their diverse assemblage. Re‐evaluation of these Malagasy forms has shed new light on this important time period in sauropod evolution.  相似文献   

14.
For the first time, remains of post-Triassic temnosponyls are described from the southern Junggar Basin (NW China). Middle Jurassic material from the uppermost part of the Toutunhe Formation consists of several isolated but well preserved skull bones and intercentra from all regions of the body that can be attributed to a brachyopid. The material in part shares important autapomorphies withGobiops desertus Shishkin, 1991, from the Upper Jurassic of Outer Mongolia, and is consequently referred to this taxon, partially with reservation. This represents the first record of this genus from China. It also yields new anatomical data and permits an emended diagnosis.Ferganobatrachus from the Middle Jurassic of Kirghisia is probably, as also shown by the new material, congeneric withGobiops. Two fragmentary specimens from the lower part of the Upper Jurassic Qigu Formation are tentatively referred to the Brachyopoidea because of features of the skull, mandible and vertebral column. They probably both represent a single taxon that was larger and more massively built thanGobiops desertus but closely related to this form.   相似文献   

15.
Abstract

Sauropod tracks from the Early Jurassic Maanshan Member of the Ziliujing Formation in the Dazhuanwan area of Guizhou represent the first Jurassic dinosaur track record for this province. The best preserved and longest trackway is narrow gauge (Brontopodus type), and indicates a relatively small trackmaker (footprint length ~35.0 cm). In conjunction with sauropodomorph skeletal remains these tracks suggest that basal sauropodomorphs and primitive sauropods coexisted in this region during the Early Jurassic. This pattern is same in the Lufeng and Sichuan basins. Thus, sauropod tracks from southwest China are diverse in the Early Jurassic, and include narrow gauge Parabrontopodus, wide gauge Brontopodus-type, and basal sauropodomorph tracks.  相似文献   

16.
Dong Ren 《Insect Science》1998,5(2):101-105
Abstract A new genus and a new species of fossil nemobiins, Liaonemobius tanae gen. et sp. nov., are described and illustrated. This is the first record of fossil cricket from China. All the specimens described here were collected from the Late Jurassic Yixian Formation of West Liaoning, China, and now are deposited in the National Geological Museum of China, Beijing.  相似文献   

17.
A rare example of a North American Jurassic hardground is found in the Carmel Formation of southwestern Utah. The Carmel hard‐ground was formed across a carbonate lagoon from an oolitic shoal seaward to a subtidal shelly facies landward. It has an abundant bivalve fauna consisting of thick layers of encrusters (the oyster Liostrea and the plicatulid Plicatula), borers (the ichnofossil Gastro‐chaenolites with the mytilid Lithophaga often preserved inside), and nestlers (the mytilid Modiolus). A rare soft‐bodied bryozoan (Arach‐nidium) is preserved by bioimmuration in the attachment scars of Liostrea; this is the first bioimmuration recorded from the Jurassic of North America, and the first bioimmuration recorded from a hard‐ground. The phoronid boring Talpina is present in some Liostrea shells; it was apparently excavated after the death of these oysters. The Carmel hardground community does not contain other fossils, such as serpulids, brachiopods, foraminiferans, and skeletal bryo‐zoans, typical of Jurassic hardgrounds elsewhere. It represents a low diversity molluscan community developed in a restricted marine environment.  相似文献   

18.
Abstract: A systematic account of highly diverse cyrtocrinid faunules from Upper Jurassic strata of ?tramberk type (Oxfordian–Tithonian) in southern Poland (Polish Carpathians) is presented. Fourteen taxa (Phyllocrinus malbosianus, Ph. stellaris, Ph. sp., Psalidocrinus armatus, Sclerocrinus compressus, Spolonicus sp. nov., Hemicrinus aff. kabanovi, Ancepsicrinus parvus gen. et sp. nov., Tetracrinus baumilleri sp. nov., Eugeniacrinites alexandrowiczi, E. cf. moravicus, E. sp., Eudesicrinus gluchowskii sp. nov. and Hemibrachiocrinus tithonicus sp. nov. are described and illustrated. Representatives of the genus Eudesicrinus, previously recorded only from the Lower Jurassic, are here shown to extend into the uppermost Jurassic. Other cyrtocrinids considered are common in Jurassic/Cretaceous strata across Europe. In the present faunules, isocrinid (Isocrinida), comatulid (Comatulida) and roveacrinid (Roveacrinida sensu Rasmussen, inclusive of Saccocoma) crinoids are associated.  相似文献   

19.
Abstract: Pleurotomaria species from lower Bajocian (Middle Jurassic) sediments of south‐western Luxembourg housed in the National Natural History Museum of Luxembourg are described. Seven species are recognized, one of which is new, Pleurotomaria faberi sp. nov. A more detailed definition of the diagnostic characters of the genus is proposed and the morphological continuity between Talantodiscus and Pleurotomaria is demonstrated, suggesting that the former cannot be considered as a distinct taxon. The palaeoecology, evolution and palaeobiogeographical history of Pleurotomaria are outlined. Pleurotomaria presumably first appeared in late Middle Triassic of New Zealand where it underwent a relative diversification up to the Hettangian (Early Jurassic). From early Hettangian, most of its evolutionary history took place in Europe and western Tethys. In the European epicontinental seas, Pleurotomaria experienced two important radiations. The first occurred in the Early Jurassic, with a peak in the late Pliensbachian, and was marked by an expansion of the distribution to the central part of western Tethys. After a collapse in species diversity, probably related to the early Toarcian anoxic event, a second radiation occurred. This culminated in the early Bajocian and was mainly confined in a region encompassing southern England, Paris Basin and southern Germany. Low‐spired species, formerly attributed to Talantodiscus, probably originated independently and iteratively during the history of Pleurotomaria. The facies and associated benthic faunas suggest that Pleurotomaria probably lived on shallow soft bottoms composed of mixed calcareous–siliciclastic sediments. The two main Early Jurassic and early Middle Jurassic radiations of the genus took place in these environments. Records of the genus in Jurassic carbonate platform deposits are very few and concern mainly post‐Bajocian species.  相似文献   

20.
植物化石气孔参数分析是目前恢复古大气二氧化碳浓度较为精准的方法之一,银杏类和松柏类等是恢复古大气CO_2浓度常用的化石类群。本文利用新疆准噶尔盆地下侏罗统三工河组的松柏类掌鳞杉科Brachyphyllum(Hirmeriella?)sp.化石对早侏罗世大气CO_2浓度进行了重建,获得早侏罗世大气CO_2浓度为~1200ppm,丰富了早侏罗世大气CO_2浓度信息,进一步说明掌鳞杉科植物通过气孔比率法在重建侏罗纪大气CO_2浓度方面的可靠性。掌鳞杉科植物的旱生构造和较高的大气CO_2浓度表明早侏罗世Toarcian期大洋缺氧事件在陆地生态系统内可能产生了一定的响应。  相似文献   

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