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11.
Isograptus ovatus davidensis subsp. nov. is described from the D. murchisoni Shales of Abereiddy Bay, Wales. This discovery gives further support to the correlation of the murchisoni Zone with the upper part of the Darriwil Stage of Victoria.  相似文献   
12.
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   
13.
Examples of early astogeny in the species Carinatocella harmeri (Stach), Costaticella hastata (Busk) and Claviporella aurita (Busk) are discussed. The primary zoid differs in each species and if found fossil, only in C. hastata could this zoid be recognised as a bryozoan fragment. Analogous development in other Bryozoa is discussed.  相似文献   
14.
Poropat, S.F., Martin, S.K., Tosolini, A.-M.P., Wagstaff, B.E, Bean, L.B., Kear, B.P., Vickers-Rich, P. &; Rich, T.H., May 2018. Early Cretaceous polar biotas of Victoria, southeastern Australia—an overview of research to date. Alcheringa 42, 158–230. ISSN 0311-5518.

Although Cretaceous fossils (coal excluded) from Victoria, Australia, were first reported in the 1850s, it was not until the 1950s that detailed studies of these fossils were undertaken. Numerous fossil localities have been identified in Victoria since the 1960s, including the Koonwarra Fossil Bed (Strzelecki Group) near Leongatha, the Dinosaur Cove and Eric the Red West sites (Otway Group) at Cape Otway, and the Flat Rocks site (Strzelecki Group) near Cape Paterson. Systematic exploration over the past five decades has resulted in the collection of thousands of fossils representing various plants, invertebrates and vertebrates. Some of the best-preserved and most diverse Hauterivian–Barremian floral assemblages in Australia derive from outcrops of the lower Strzelecki Group in the Gippsland Basin. The slightly younger Koonwarra Fossil Bed (Aptian) is a Konservat-Lagerstätte that also preserves abundant plants, including one of the oldest known flowers. In addition, insects, crustaceans (including the only syncaridans known from Australia between the Triassic and the present), arachnids (including Australia’s only known opilione), the stratigraphically youngest xiphosurans from Australia, bryozoans, unionoid molluscs and a rich assemblage of actinopterygian fish are known from the Koonwarra Fossil Bed. The oldest known—and only Mesozoic—fossil feathers from the Australian continent constitute the only evidence for tetrapods at Koonwarra. By contrast, the Barremian–Aptian-aged deposits at the Flat Rocks site, and the Aptian–Albian-aged strata at the Dinosaur Cove and Eric the Red West sites, are all dominated by tetrapod fossils, with actinopterygians and dipnoans relatively rare. Small ornithopod (=basal neornithischian) dinosaurs are numerically common, known from four partial skeletons and a multitude of isolated bones. Aquatic meiolaniform turtles constitute another prominent faunal element, represented by numerous isolated bones and articulated carapaces and plastrons. More than 50 specimens—mostly lower jaws—evince a high diversity of mammals, including monotremes, a multituberculate and several enigmatic ausktribosphenids. Relatively minor components of these fossil assemblages are diverse theropods (including birds), rare ankylosaurs and ceratopsians, pterosaurs, non-marine plesiosaurs and a lepidosaur. In the older strata of the upper Strzelecki Group, temnospondyl amphibians—the youngest known worldwide—are a conspicuous component of the fauna, whereas crocodylomorphs appear to be present only in up-sequence deposits of the Otway Group. Invertebrates are uncommon, although decapod crustaceans and unionoid bivalves have been described. Collectively, the Early Cretaceous biota of Victoria provides insights into a unique Mesozoic high-latitude palaeoenvironment and elucidates both palaeoclimatic and palaeobiogeographic changes throughout more than 25 million years of geological time.

Stephen F. Poropat*? [; ], Faculty of Science, Engineering and Technology, Swinburne University of Technology, John St, Hawthorn, Victoria 3122, Australia; Sarah K. Martin*? [; ] Geological Survey of Western Australia, 100 Plain St, East Perth, Western Australia 6004, Australia; Anne-Marie P. Tosolini [] and Barbara E. Wagstaff [] School of Earth Sciences, The University of Melbourne, Melbourne, Victoria 3010, Australia; Lynne B. Bean [] Research School of Earth Sciences, Australian National University, Acton, Canberra, Australian Capital Territory 2001, Australia; Benjamin P. Kear [] Museum of Evolution, Uppsala University, Norbyvägen 16, Uppsala SE-752 36, Sweden; Patricia Vickers-Rich§ [; ] Faculty of Science, Engineering and Technology, Swinburne University of Technology, John St, Hawthorn, Victoria 3122, Australia; Thomas H. Rich [] Museum Victoria, PO Box 666, Melbourne, Victoria 3001, Australia. *These authors contributed equally to this work. ?Also affiliated with: Australian Age of Dinosaurs Museum of Natural History, Lot 1 Dinosaur Drive, PO Box 408, Winton, Queensland 4735, Australia. ?Also affiliated with: Earth and Planetary Sciences, Western Australian Museum, Welshpool, Western Australia 6101, Australia. §Also affiliated with: School of Earth, Atmosphere and Environment, Monash University, Melbourne, Victoria 3800, Australia.  相似文献   
15.
Cetricycas antarcticus gen. et sp. nov. occurs in the Late Coniacian to Campanian Lachman Crags Member of the Santa Marta Formation, Marambio Group, James Ross Island, Antarctica. The petrified trunk comprises a thick pith containing thin and thick walled parenchymous cells, vascular traces surrounded by a thin layer of loose secondary wood. Medullary bundles arise inside the wood zone and pass outwards through multiseriate medullary rays. The trunk anatomy indicates assignment to the Cycadales, and the presence of medullary bundles indicates the affinities with a clade comprising Lepidozamia, Macrozamia, and Encephalartos. This clade is presently confined to Australia and Africa, but fossil representatives extend the geographic range to India, South America and now Antarctica.  相似文献   
16.
Siversson, M. & Machalski, M., February 2017. Late late Albian (Early Cretaceous) shark teeth from Annopol, Poland. Alcheringa 41, 433–463.

Screen washing of the condensed phosporite-bearing sands at the top of the Albian succession at Annopol, Poland, produced 789 selachian teeth of which 264 are determinable to at least genus level. The sediment type and methods of processing prevented recovery of small-toothed taxa, resulting in an assemblage comprising 13, mostly large-toothed taxa. Lamniformes dominates with Dwardius sp. being, by far, the most common taxon. Observations on vertical distribution and preservation of the teeth (with focus on the adhered phosphatic matrix), coupled with biostratigraphic ranges of co-occurring ammonites, indicate that the majority of the shark material is attributable to the Mortoniceras rostratum or, more probably, M. perinflatum Zone (late late Albian; mid-‘Vraconnian’). This is compatible with the composition of the shark assemblage, characterized by the co-occurrence of Paraisurus sp. aff. P. compressus, Cretoxyrhina vraconensis and Squalicorax teeth with strong serrations on the cutting edges. The tightly curved basal edge of the root in lateral teeth of C. vraconensis conforms to that of teeth from the Pawpaw Formation of Texas (M. rostratum Zone) and differs from the more divergent root lobes in younger specimens from the uppermost Albian and/or lowermost Cenomanian of Kolbay, Mangyshlak. Some specimens in the studied assemblage are probably older, within the range from the middle to earliest late late Albian. The strong numerical dominance of either Cretoxyrhina or Dwardius in late late Albian to early Cenomanian selachian faunas indicates competitive exclusion in these similar-sized, apex predatory sharks.

Mikael Siversson* [], Department of Earth and Planetary Sciences, Western Australian Museum, 49 Kew Street, Welshpool, Western Australia 6106, Australia; Marcin Machalski [], Institute of Paleobiology, Polish Academy of Sciences, ul. Twarda 51/55, 00-818 Warszawa, Poland. *Also affiliated with: Department of Environment & Agriculture, Curtin University, Kent Street, Bentley, WA 6102, Australia.  相似文献   

17.
Zheng, D., Zhang, Q., Nel, A., Jarzembowski, E.A., Zhou, Z., Chang, S.-C. &; Wang, B., May 2016. New damselflies (Odonata: Zygoptera: Hemiphlebiidae, Dysagrionidae) from mid-Cretaceous Burmese amber. Alcheringa XX, xxx–xxx. ISSN 0311-5518

Two damselflies, Burmahemiphlebia zhangi gen. et sp. nov. and Palaeodysagrion cretacicus gen. et sp. nov., are described from the mid-Cretaceous Burmese amber. Burmahemiphlebia zhangi is the first record of Hemiphlebiidae from this amber, although the family was cosmopolitan during the Mesozoic. It can be readily distinguished from all other members of Hemiphlebiidae in having very short MP and CuA veins, and in its rectangular discoidal cell. The new fossils support the view that hemiphlebiid damselflies were one of the dominant groups of Zygoptera during the Mesozoic. Palaeodysagrion cretacicus is the first dysagrionid damselfly from Burmese amber and the second Mesozoic representative of this predominantly Paleogene group. It differs from other members of Dysagrionidae in having a unique elongate discoidal cell. These new finds increase the diversity of damselflies in mid-Cretaceous Burmese amber.

Daran Zheng* [], Su-Chin Chang [], Department of Earth Sciences, The University of Hong Kong, Hong Kong Special Administrative Region, PR China; Qingqing Zhang [], Edmund A. Jarzembowski? [], Bo Wang? [], State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, 39 East Beijing Road, Nanjing 210008, PR China; André Nel [], Institut de Systématique, Évolution, Biodiversité, ISYEB-UMR 7205-CNRS, MNHN, UPMC, EPHE, Muséum national d’Histoire naturelle, Sorbonne Universités, 57 rue Cuvier, CP 50, Entomologie, F-75005, Paris, France; Zhicheng Zhou [], The PLA Information Engineering University, 62 Kexue Ave, Gaoxin District, Zhengzhou 450002, Henan, PR China. *Also affiliated with State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, 39 East Beijing Road, Nanjing 210008, PR China. ?Also affiliated with Department of Earth Sciences, The Natural History Museum, London SW7 5BD, UK. ?Also affiliated with Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, PR China.  相似文献   
18.
A review is undertaken of the nine species of Procytherura known to occur in Argentina and a new species, Procytherura serangodes sp. nov. is described. The global distribution of the genus indicates that it was more or less equally diverse and widely distributed in both hemispheres during most of the Lower and Middle Jurassic, but that in the Upper Jurassic and in the Lower Cretaceous, it became progressively restricted to the Southern Hemisphere. The widespread distribution of several Jurassic species of Procytherura, which occur in both Great Britain and Northwest Europe and in Argentina, is shown to be related to the availability of important migration routes, including the Tethys and the Hispanic Corridor. In the Lower Cretaceous, the very widespread distribution of Procytherura in the Southern Hemisphere, is used to support the existence of important routes along the eastern and western seaboards of Africa, the latter associated with the opening of the South Atlantic.  相似文献   
19.
Vera, E.I. iFirstarticle. Millerocaulis tekelili sp. nov., a new species of osmundalean fern from the Aptian Cerro Negro Formation (Antarctica). Alcheringa, 1–10. ISSN 0311-5518.

Ezequiel Ignacio Vera [evera@macn.gov.ar] División Paleobotánica, Museo Argentino de Ciencias Naturales 'Bernardino Rivadavia', Av. Angel Gallardo 470, C1524DJR, Buenos Aires, Argentina. Also affiliated with Área de Paleontología, Departamento de Ciencias Geológicas, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Pabellón II, Ciudad Universitaria, C1428EGA, Buenos Aires, Argentina. Received 29.10.2010, revised 14.3.2011; accepted 24.3.2011.

A new species of the osmundalean fossil morphogenus Millerocaulis Tidwell emend. Vera, Millerocaulis tekelili sp. nov. is defined, based on several permineralized stems recovered from exposures of the Lower Cretaceous Cerro Negro Formation on Livingston Island, South Shetland Islands, Antarctica. This new species is characterized by the presence of an ectophloic–dictyoxylic siphonostele, inner parenchymatic and outer sclerotic cortices, heterogeneous sclerotic ring in the petiole bases, absence of sclerenchyma associated with the petiolar xylem trace, petiolar inner cortex with sclerenchyma strands and stipular wings having a large sclerenchyma bundle and several smaller ones. The presence of non-homogeneous sclerotic rings in the petiole bases allows this new species to be clearly distinguished from other Antarctic Millerocaulis, and suggests that it may represent an intermediate form in the evolutionary lineage leading from Millerocaulis to subgenus Claytosmunda of Osmunda.  相似文献   
20.
Mesofossil assemblages from several Cretaceous and Cenozoic units across Australia and New Zealand provide new evidence of insect and annelid behaviour. The earliest scale insects (Diaspididae, Coccoidea) from Australasia are described and represented by three scale morphotypes. The mesofossil assemblages also reveal clitellate annelid cocoon morphotypes, three morphotypes of arthropod coprolites and several insect piercement structures on gymnosperm leaf or stem fragments, possibly related to feeding or more likely oviposition. This research offers a new avenue for detecting cryptic terrestrial invertebrate groups and their interactions, particularly with plants, in the fossil record. The fossils demonstrate that insect/invertebrate activity can be preserved and identified in mesofossil suites, that such traces and exoskeleton fragments are relatively common in acid-extracted mesofossil suites, and that recognizable categories occur on multiple landmasses and at various ages.  相似文献   
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