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1.
Marsola, J.C.A., Grellet-Tinner, G., Montefeltro, F.C., Sayão, J.M., Hsiou, A.S. & Langer, M.C., 2014. The first fossil avian egg from Brazil. Alcheringa 38, 563–567. ISSN 0311-5518.

In contrast to the rich record of eggs from non-avian dinosaurs, complete eggs attributable to Mesozoic birds are relatively scarce. Nevertheless, several well-preserved specimens have been discovered over the last three decades revealing functional and phylogenetic characters that shed light on the breeding strategies of extinct birds. Here we report the first fossil avian egg from Brazil, which was discovered in Upper Cretaceous strata of São Paulo in the southeastern part of the country. The taxonomic identity and structural features of the biomineralized tissues were determined using a combination of Scanning Electron Microscopy, Wave Dispersion Energy analyses and Computed Tomography. These show that the 125.5-μm-thick shell of the 31.4?×?19.5?mm egg incorporates three structural layers of similar thickness with both prismatic and aprismatic boundaries. Close similarity between the Brazilian bird egg and those of enantiornithines from the Upper Cretaceous Bajo de la Carpa Formation (Río Colorado Subgroup) of Argentina advocates affinity with basal Ornithothoraces. Furthermore, coherency of their depositional contexts might imply a compatible preference for breeding and nesting environments.

Júlio Cesar de A. Marsola [], Annie Schmaltz Hsiou [] and Max C. Langer [], Laboratório de Paleontologia de Ribeirão Preto, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes 3900, Ribeirão Preto, São Paulo state, 14040-901, Brazil. Gerald Grellet-Tinner [], Centro Regional de Investigaciones La Rioja—Consejo Nacional de Investigaciones Científicas y Técnicas, Entre Ríos y Mendoza s/n, 5301 Anillaco, Argentina; Orcas Island Museum, PO Box 134, 181 North Beach Road, Eastsound, WA 98245. Felipe C. Montefeltro [], Departamento de Zoologia, Universidade Estadual Paulista, Avenida 24A 1515, Rio Claro, São Paulo State, 13506-900, Brazil. Juliana M. Sayão [], Laboratório de Diversidade do Nordeste, Núcleo de Biologia, Centro Acadêmico de Vitória, Universidade Federal de Pernambuco, Rua do Alto do Reservatório s/n, Bela Vista, Vitória de Santo Antão, Pernambuco state, 52050-480, Brazil. Received 18.12.2013; revised 30.4.2014; accepted 18.5.2014.  相似文献   

2.
    
The first caviine rodent referable to Galea Meyen, 1832 is described from the late Pleistocene of southern Brazil based on a left dentary with the p4–m3 series. The specimen derives from the Ponte Velha I locality in the Touro Passo Creek (Touro Passo Formation, upper Pleistocene), western Rio Grande do Sul State. The main characters used to assign this specimen to Galea are: anterior area of horizontal crest at the level of prism I of p4; deep anterior area of masseteric fossa; incisor alveolus on the medial face of the dentary extended up to the level of prism II of m2; and presence of cement in the hypoflexid. Currently, the genus has a disjunct distribution, with a group in Argentina, Bolivia and Peru, and another in northern and northeastern Brazil. The presence of this taxon in Pleistocene deposits of Rio Grande do Sul State, Uruguay and the Argentine Mesopotamian, where there are no extant representatives of the genus, indicates its wider distribution during the late Pleistocene.  相似文献   

3.
Simões, M.G., Quaglio, F., Warren, L., Anelli, L.E., Stone, P., Riccomini, C., Grohmann, C.H. & Chamani, M.A.C. December 2012. Permian non-marine bivalves of the Falkland Islands and their palaeoenvironmental significance. Alcheringa 36, 543–554. ISSN 0311-5518.

We describe the occurrence of non-marine bivalves in exposures of the Middle Permian (Capitanian) Brenton Loch Formation on the southern shore of Choiseul Sound, East Falklands. The bivalves are associated with ichnofossils and were collected from a bed in the upper part of the formation, within a 25 cm thick interval of dark siltstones and mudstones with planar lamination, overlain by massive sandstones. The shells are articulated, with the valves either splayed open or closed. At the top of the succession, mudstone beds nearly 1.5 m above the bivalve-bearing layers yielded well-preserved Glossopteris sp. cf. G. communis leaf fossils. The closed articulated condition of some shells indicates preservation under high sedimentation rates with low residence time of bioclasts at the sediment/water interface. However, the presence of specimens with splayed shells is usually correlated to the slow decay of the shell ligament in oxygen-deficient bottom waters. The presence of complete carbonized leaves of Glossopteris associated with the bivalve-bearing levels also suggests a possibly dysoxic-anoxic bottom environment. Overall, our data suggest that the bivalves were preserved by abrupt burial, possibly by distal sediment flows into a Brenton Loch lake, and may represent autochthonous to parautochthonous fossil accumulations. The shells resemble those of anthracosiids and are herein assigned to Palaeanodonta sp. aff. P. dubia, a species also found in the Permian succession of the Karoo Basin, South Africa. Our results confirm that (a) the true distributions in space and time of all Permian non-marine (freshwater) bivalves are not yet well known, and (b) there is no evidence for marine conditions in the upper part of the Brenton Loch Formation.  相似文献   

4.
Fourteen Bivalvia species are described from the Lower Permian Río Genoa Formation, exposed in the southern Tepuel-Genoa Basin (Chubut Province, Argentina), of which one, Fletcheripecten genoensis, is new. The studied specimens are well preserved, retaining fine details of the ornament and shell morphology. Palaeotaxodonta is represented by two species of Nuculopsis and four species of Phestia; Pteriomorphia by five species in five genera; and Heteroconchia by three informal species. Most of the species recorded also occur in the northern part of Tepuel-Genoa Basin and allow demarcation of new and distinct marine intervals in the Río Genoa Formation, which was classically interpreted to represent continental deposits. The bivalve fauna confirms a Cisuralian (Early Permian) age for the Río Genoa Formation and offers potential for improved regional and global correlations.  相似文献   

5.
Unconsolidated sediments from a borehole in Botany Bay have been analyzed for their foraminiferal content. Faunas from between 41 and 54 m below sea level are interpreted as Pleistocene in age. The foraminiferal assemblage from 54 m indicates marine conditions of moderately deep water (25–30 m), and a climate warmer than at present. The higher assemblages indicate a more brackish environment

The foraminifera, belonging to 123 species in 67 genera, are tabulated and 24 are discussed and illustrated. Three species, Oolina bifidocostata, Fissurina alatoquadrata and Elphidium botaniensis and one subpecies, Quinqueloculina affinis atrata, are described as new.  相似文献   

6.
7.
Wang, Q., Wang, Y., Qi, Y., Wang, X., Choh, S.J., Lee, D.C. & Lee, D.J., November 2017. Yeongwol and the Carboniferous–Permian boundary in South Korea. Alcheringa 42, 245–258. ISSN 0311-5518

Six conodont and one fusuline zones are recognized on basis of a total of 25 conodont and 13 fusuline species (including seven unidentified species or species given with cf. or aff. in total) from the Bamchi Formation, Yeongwol, Korea. The conodont zones include the Streptognathodus bellus, S. isolatus, S. cristellaris, S. sigmoidalis, S. fusus and S. barskovi zones in ascending order, which can be correlated with the conodont zones spanning the uppermost Gzhelian to Asselian Age of the Permian globally. The fusuline zone is named the Rugosofusulina complicata–Pseudoschwagerina paraborealis zone. The co-occurrence of the conodont Streptognathodus isolatus (the Global Boundary Stratotype Section and Point index for the base of Permian) and Pseudoschwagerina (a Permian inflated fusuline) indicates that the Carboniferous–Permian boundary can be placed in the lower part of the Bamchi Formation in South Korea.

Qiulai Wang* [] CAS Key Laboratory of Economic Stratigraphy and Palaeogeography, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, East Beijing Road 39, Nanjing 210008, PR China; Yue Wang* [] LPS, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, East Beijing Road 39, Nanjing 210008, PR China; Yuping Qi* [] Xiangdong Wang* [] CAS Key Laboratory of Economic Stratigraphy and Palaeogeography, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, East Beijing Road 39, Nanjing 210008, PR China; Suk-Joo Choh [] Department of Earth and Environmental Sciences, Korea University, Seoul 02841, Republic of Korea; Dong-Chan Lee [] Department of Earth Sciences Education, Chungbuk National University, Cheongju 28644, Republic of Korea; Dong-Jin Lee [] Department of Earth and Environmental Sciences, Andong National University, Andong 36729, Republic of Korea. *Also affiliated with: University of Chinese Academy of Sciences, 19A Yuquan Road, Shijingshan District, Beijing 100049, PR China.  相似文献   


8.
The paper contributes to notions of ‘hybrid’ historical geographies of irrigation by focusing on contested visions for irrigation in the Lower Rio Grande Valley of Texas. Adding to geographical work using biography, notions of performance, and racialized landscapes, the paper analyzes debates between John Shary and Charles Pease. Shary and Pease were protagonists, respectively, of pumping water from the Rio Grande and a gravity scheme reliant on action by the U.S. Bureau of Reclamation. The pumping system survived; the gravity system was never constructed. However, the debate between Shary and Pease illustrates tensions within the Anglo elite. The analysis focuses on three early-twentieth-century moments. The first is a 1918 crisis in Shary’s irrigation company, followed by a 1927 debate between Shary and Pease over the flaws of the pumping system and benefits of gravity irrigation. Finally, the paper focuses on Shary and Pease’s constructions of racialized landscapes that subordinated Hispanics as voters to be utilized for Shary’s accumulation strategy, or as ‘non-water users’ that should be excluded from water politics. The paper argues that Shary and Pease projected similarly exclusionary social visions onto the irrigated landscape in spite of their differences on irrigation systems.  相似文献   

9.
10.
    
Zhen, Y.Y., Normore, L.S., Dent, L.M. & Percival, I.G., 11 July 2019. Middle Ordovician (Darriwilian) conodonts from the Goldwyer Formation of the Canning Basin, Western Australia. Alcheringa 44, 25–55. ISSN 0311-5518

Middle Ordovician conodonts attributed to 46 species were recovered from a stratigraphic interval spanning the Willara, Goldwyer and Nita formations in core sections from the Sally May-2 and Theia-1 petroleum exploration wells in the Canning Basin, Western Australia. The Histiodella serrata, Histiodella holodentata and Eoplacognathus pseudoplanus biozones are recognized in the lower and middle part of the Goldwyer Formation, indicative of an early–middle Darriwilian age. This revised conodont biostratigraphy enables more precise correlation with North America and North and South China. Several biogeographically distinctive conodont species, most likely of North Chinese origin, are recorded from the Goldwyer Formation. Their presence signals a strong palaeobiogeographic connection between the Sino-Korean Craton and the Canning Basin on the western margin of eastern Gondwana during the late Middle Ordovician.

Y.Y. Zhen* [yong-yi.zhen@planning.nsw.gov.au], W.B. Clarke Geoscience Centre, Geological Survey of New South Wales, 947–953 Londonderry Road, Londonderry NSW 2753, Australia; L.S. Normore [leon.normore@dmirs.wa.gov.au]; L.M. Dent [louisa.dent@dmirs.wa.gov.au], Department of Mines, Industry Regulation and Safety, Mineral House, Geological Survey of Western Australia, 100 Plain Street, East Perth, WA 6004, Australia; I.G. Percival [ian.percival@planning.nsw.gov.au], W.B. Clarke Geoscience Centre, Geological Survey of New South Wales, 947–953 Londonderry Road, Londonderry NSW 2753, Australia;  相似文献   

11.
    
Foraminiferal assemblage from Permian rocks of Eastern Himalaya, India are recorded for the first time. Twenty-two genera and twenty-eight species are documented from the Garu Formation, Eastern Himalaya. The foraminiferal assemblage supports previous age determinations based on megafauna. The distinctive foraminiferal assemblage from India supports the recognition of Australian and Afghanistan-Indian provinces in the Early Permian Austral realm. An appreciable number of common species in these provinces is indicative of close geographic links.  相似文献   

12.
González, C. R., Early carboniferous Bivalvia from western Argentina. Alcheringa 18, 169–185. ISSN 0311-5518.

Lower Carboniferous deposits of western Argentina yield invertebrates and plant remains. In the Tournaisian epoch, a transgression from the ‘Pacific’ flooded the Rio Blanco Basin, forming a semi-restricted inland sea. Marine invertebrates of this age comprise the Malimanian fauna, which is based on the Protocanites-Rossirhynchus Assemblage. Eleven species of Bivalvia are here described Palaeoneilo subquadratum sp. nov., Malimania triangularis gen. et sp. nov., Phestia sp., Volsellina? sp. Posidoniella malimanensis sp. nov., Leptodesma? sp., Schizodus sp., Cypricardinia? sp., Edmondia? sp., Sanguinolites punillanus sp. nov., and Vacunella? sp. nov. They are accompanied by gastropods, trilobites, conularids and corals. The Malimanian fauna is regarded as a poorly to moderately varied assemblage that was influenced by some basinal restrictions. It was probably connected to faunas of Chile and Peru, and lived during a stage of mild climate before the beginning of the Late Palaeozoic ice age.  相似文献   

13.
    
The cosmopolitan, Jurassic to Recent, bivalve Acesta (Limidae) is documented from Australian Cretaceous (upper Albian) rocks in the lowermost section of the Mackunda Formation of Queensland. These specimens from Landsborough Downs, Flinders Shire, represent an endemic new species, herein named Acesta (Acesta) backae n. sp. Acesta (A.) backae n. sp. was a shallow-water suspension feeder that inhabited the Cretaceous Australian epicontinental sea of the Great Artesian Basin. Although hinge details of Acesta (A.) backae n. sp. are wanting, this new taxon is most closely allied with Acesta? sp. of the Miria Formation of Western Australia and can clearly be discriminated from other Cretaceous Austral forms.  相似文献   

14.
《范登堡决议案》是美国大西洋联盟政策中的重要一环,在战后初期美国外交中发挥了重要作用。该决议案所确立的一些政治原则,如联合国框架下的"区域性安全"与"独立和集体自我防御"原则、"自助与相互援助"原则,成为大西洋联盟政策所尊奉的圭臬,对美国外交政策、国内政治实践、美欧联盟关系等,均产生了重要影响。但是,《范登堡决议案》也加剧了美国外交政策中的冷战对抗性;从长远看,《范登堡决议案》导致了美国内政外交的不稳定发展。  相似文献   

15.
An unusual occurrence in the upper Albian Toolebuc Formation of Queensland, Australia, of penetration of a guard of the belemnite Dimitobelus (Dimitobelus) stimulus into the disc of an indeterminate inoceramid bivalve, is the first report of this type of shell damage in the fossil record. The belemnite punctured completely both valves of the bivalve to the maximum diameter of the belemnite guard, by inferred compaction from sediment overburden during post-mortem biostratinomic processes. Shell thickening of the inoceramid bivalve by shearing of prismatic layers at the site of puncture indicates that the bivalve shell behaved plastically during the puncture and that the great flexibility of the prismatic layers was facilitated by the relatively thin shell and presence of organic sheaths around individual prisms. This flexibility may have been advantageous during a predatory attack, by allowing the maintenance of a seal during breakage of the shell margin.  相似文献   

16.
Fragmentary remains of the first long snouted temnospondyls from the Triassic of Queensland are described. One is the first vertebrate fossil from the Glenidal Formation, while the other adds another member to the extensive fauna of the Arcadia Formation. Both specimens are placed provisionally in the Family Trematosauridae.  相似文献   

17.
Wang, Z.H., Bergström, S.M., Zhen, Y.Y., Chen, X. & Zhang, Y.D., 2013. On the integration of Ordovician conodont and graptolite biostratigraphy: New examples from Gansu and Inner Mongolia in China. Alcheringa 37, 510–528. ISSN 0311-5518.

Few Ordovician successions in the world contain both biostratigraphically highly diagnostic conodonts and graptolites permitting an integration between standard biozones based on these fossil groups. The Sandbian Guanzhuang section in the vicinity of Pingliang in the Gansu Province has an outstanding graptolite record through most of the Nemagraptus gracilis and Climacograptus bicornis graptolite biozones. Calcareous interbeds in the succession yield biostratigraphically important conodonts, including some species used for biozonations in Baltoscandia and the North American Midcontinent. Likewise, the middle–upper Darriwilian Dashimen section in the Wuhai region of Inner Mongolia hosts both diverse graptolites of the Pterograptus elegans, Didymograptus murchisoni and lowermost Nemagraptus gracilis biozones, and conodonts of Midcontinent and Baltoscandic types. The distribution patterns of these index fossil groups provide an unusual opportunity to closely correlate conodont and graptolite biozones in the middle to upper Darriwilian to Sandbian interval. For instance, the base of the C. bicornis Biozone is approximately coeval with the base of the Baltoscandic B. gerdae Subbiozone and a level near the middle of the North American P. aculeata Biozone.

Zhi-hao Wang [zhwang@nigpas.ac.cn] Xu Chen [xu1936@gmail.com], and Yuan-dong Zhang [ydzhang@nigpas.ac.cn], Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China; Stig M. Bergström [stig@geology.ohio-state.edu], School of Earth Sciences, Division of Earth History, The Ohio State University, Columbus, OH 43210, USA; Yong Yi Zhen [yongyi.zhen@austmus.gov.au], Australian Museum, 6 College Street, Sydney NSW 2010, Australia.  相似文献   

18.
    
This article focuses on a community located in downtown Rio de Janeiro that was destroyed to make way for the commemorations of Brazil’s Centenary of Independence in 1922. Morro do Castelo was once a space customarily inhabited by Afro-descendants, but Italian and Portuguese immigrants predominated there by the time of its destruction. I argue that whatever Castelo’s racial heterogeneity it was imagined and treated as a black space by planners and policy makers, hence its disposability. In Castelo's neglect during the colonial period and in the urbanization projects that sought to destroy it in the first two decades of the 20th century, one can discern the continuity of imperial processes of ruination of racialized spaces and bodies. The article examines ways in which residents of Morro do Castelo established territory and engaged in various forms of refusal when faced with the ruination of their neighborhood. The spatial practices of the hillside’s diverse population suggest that its various racialized and ethnic groups mapped difference onto a palimpsestic site that defied official classificatory systems and troubled official mappings of the concept city.  相似文献   

19.
    
Place names have the potential to aid in the investigation of regional settlement histories because they reflect the importance of specific locations in the social or cultural memories of indigenous groups. Unique place names for ancient habitation sites such as villages or hamlets, i.e., those names for which there are no cognates in other languages, suggest that those ancient villages or hamlets still retain the names given to them by their original inhabitants. Here, we present Tewa place names for habitation sites identified archaeologically in the northern Rio Grande Valley of New Mexico. The results of our study strongly suggest that the Tewa language was spoken in the northern Rio Grande Valley, specifically, within the southern Tewa Basin, as early as the Late Developmental period (a.d. 900–1200), thus challenging the currently well-accepted model postulating a Mesa Verde origin for the Tewa language and culture.  相似文献   

20.
For years archaeologists in New Mexico, particularly in the northern Rio Grande region have noticed a very fine-grained what appeared to be mafic or basalt raw material source in late Paleoindian and Archaic contexts in northern New Mexico and southern Colorado. Indeed, a number of Folsom, Cody, Plainview, and Archaic bifaces are produced from this material. It appeared that there were at least two possible very fine-grained volcanics that could be the sources for these raw materials – San Antonio Mountain in far northern New Mexico, in the Taos Plateau Volcanic Field, and Cerros del Rio, on the east side of Bandelier National Monument right above the Rio Grande. After reconnaissance collections at the two probable sources, the short story is that the vast majority of “basalt” artifacts were indeed produced from one of these sources, but they are petrologically dacite and silicic volcanic rocks. An additional dacite source, called here the “Newman Dome”, also in the Taos Plateau Volcanic Field was discovered in the 1980s, but remained mainly discussed in the gray literature by CRM archaeologists. Examination of various Paleoindian and Archaic collections from the northern and middle Rio Grande indicates a strong preference for this silicic rock for the production of chipped stone tools, and in concert with obsidian source provenance studies has increased our ability to reconstruct procurement and range in these preceramic periods. These high-alkali dacite sources are easily discriminated with their trace element compositions, and based on this study, procurement seems to be dominantly restricted to these three sources in the region. Here I discuss the petrology, geochemistry, and some of the archaeological issues of these sources and their utility in the Southwest archaeological endeavor in an effort to bring these important prehistoric raw materials into the published realm.  相似文献   

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