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51.
Cao, Y., Shih, C., Bashkuev, A. & Ren, D., September 2015. Revision and two new species of Itaphlebia (Nannochoristidae: Mecoptera) from the Middle Jurassic of Inner Mongolia, China. Alcheringa 40, XX–XX. ISSN 0311-5518.

Two new species of Itaphlebia Sukatsheva, 1985, Itaphlebia longiovata and I. amoena (Nannochoristidae Tillyard, 1917), are described and illustrated from the Middle Jurassic Jiulongshan Formation of Daohugou, Inner Mongolia, China. Previously described Middle Jurassic nannochoristid genera, Chrysopanorpa Ren in Ren et al., 1995 and Protochoristella Sun, Ren & Shih, 2007b, together with Stylopanorpodes and Netropanorpodes Sun, Ren & Shih, 2007a (originally assigned to Mesopanorpodidae) are revised and considered to be synonyms of Itaphlebia. The following tentative species synonymies are proposed: Protochoristella formosa and Stylopanorpodes eurypterus = Itaphlebia ruderalis (Ren in Ren et al., 1995), comb. nov.; Netropanorpodes sentosus = I. jeniseica Novokshonov, 1997a, syn. nov.; and Protochoristella polyneura = I. multa Novokshonov, 1997a, syn. nov. Netropanorpodes decorosus is transferred to Itaphlebia. These new species, new material and the new combinations broaden the diversity of the Itaphlebia in mid-Mesozoic ecosystems and provide new characters enabling amendment of the generic diagnosis.

YiZi Cao [], ChungKun Shih [] and Dong Ren [], College of Life Sciences, Capital Normal University, Xisanhuanbeilu 105, Haidian District, Beijing, PR China 100048; Alexei Bashkuev [], Borissiak Paleontological Institute, Russian Academy of Sciences, Profsoyuznaya st. 123, Moscow 117997, Russia.  相似文献   

52.
Sagasti, A.J., García Massini, J., Escapa, I.H., Guido, D.M. & Channing, A., August 2016. Millerocaulis zamunerae sp. nov. (Osmundaceae) from Jurassic geothermally influenced wetland environments of Patagonia, Argentina. Alcheringa 40, xxx–xxx. ISSN 0311-5518

A new species of Millerocaulis Erasmus ex. Tidwell emend. Vera is defined based on several permineralized stems recovered from geothermally influenced chert deposits in the Middle–Late Jurassic La Matilde Formation (Santa Cruz, Argentina). Millerocaulis zamunerae sp. nov. is characterized by the presence of an ectophloic dictyoxylic siphonostele, inner parenchymatic and outer sclerotic cortices, homogeneous sclerotic ring in the petiole bases, two masses of sclerenchyma lining the concavity of the petiolar vascular bundle, petiolar inner cortex with sclerenchyma strands in the outermost petiole cycles and stipular wings having one large and several smaller sclerenchyma bundles. Millerocaulis zamunerae inhabited geothermal wetlands and other hot-spring-related sedimentary facies associated with the La Bajada epithermal deposit. Reference to active geothermal wetlands, analogous living plants and other fossil hot spring ecosystems suggest the plant’s tolerance of physico-chemical stressors including elevated temperature, pH, salinity and phytotoxic metals/metalloids. Millerocaulis zamunerae thrived in wetlands preserved in the Jurassic geothermal systems of Santa Cruz Province, the same kind of environment in which Equisetum thermale Channing et al. was recorded previously.

Ana Julia Sagasti [] División Paleobotánica, Facultad de Ciencias Naturales y Museo. Becaria Doctoral Consejo Nacional de Investigaciones Científicas y Técnicas, Paseo del Bosque S/N B1900FWA La Plata, Buenos Aires, Argentina. Juan García Massini [] Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja (CRILAR), Provincia de La Rioja, UNLaR, SEGEMAR, UNCa, CONICET. Entre Ríos y Mendoza S/N, 5301 Anillaco, La Rioja Argentina. Ignacio H. Escapa [] Museo Paleontológico Egidio Feruglio, Consejo Nacional de Investigaciones Científicas y Técnicas, Av. Fontana 140, U9100GYO, Trelew, Chubut, Argentina. Diego M. Guido [] Instituto de Recursos Minerales (INREMI), Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata. Consejo Nacional de Investigaciones Científicas y Técnicas. Calle 64 y 120, La Plata (1900), Argentina. Alan Channing [] School of Earth & Ocean Sciences, Cardiff University, Cardiff CF10 3AT, UK.  相似文献   
53.
CaramÉs, A., Martinez, M., Concheyro, A., RemÍrez, M. & Adamonis, S., 6 August 2019 2019. Holothuroidea: new records from the Lower Cretaceous of the Agrio Formation, Neuquén Basin, Argentina. An integrated study with foraminifers and calcareous nannofossils. Alcheringa XX, xx–xx. ISSN 0311-5518

New records of holothurian ossicles (Echinodermata) from the Lower Cretaceous Agrio Formation, Mendoza Group, in the northern Neuquén Basin, west-central Argentina, represent, excepting some general mention of ossicles, the first collection from the Lower Cretaceous of South America. The discovery is one of the few worldwide records of holothurian remains from this age. The analysed skeletal elements are associated with other microfauna and nannoflora retrieved from washed residues of claystones and marlstones of the lower strata of the Pilmatué Member, in Área 3000 and Puerta Curaco sections. The calcareous microfossil assemblage is composed almost exclusively of the foraminifera Epistomina loncochensis, suggesting quiet marine environments and low levels of dissolved oxygen in the bottom/water interface. A late Valanginian age is confirmed by the nannofossil assemblage found together with the holothurian ossicles. Analysis of ossicle shapes allows their attribution to molpadiids (Molpadida: Molpadiidae): one two-armed racquet-like single ossicle that remains as an indeterminate molpadiid and a new genus and species proposed for the abundant cross-shaped and star-shaped ossicles. The latter, owing to the presence of four holes and the lack of a spire or some elevation projecting well out from surface in the centre of the plates, resemble two known species of the genus Cruxopadia Reich, but they differ in their arm morphology.

Andrea Caramés [], IDEAN—Instituto de Estudios Geológicos Andinos ‘Don Pablo Groeber’, CONICET, Ciudad Universitaria Pabellón II, Intendente Güiraldes 2160-C1428EHA Buenos Aires, Argentina; Mariano Martinez [], Museo Argentino de Ciencias Naturales ‘Bernardino Rivadavia’, CONICET, A. Gallardo 470-C1405DJR Buenos Aires, Argentina; Andrea Concheyro [], IDEAN—Instituto de Estudios Geológicos Andinos ‘Don Pablo Groeber’, CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria Pabellón II, Intendente Güiraldes 2160-C1428EHA Buenos Aires, Argentina, and Instituto Antártico Argentino, Argentina; Mariano Remírez [], CIG—Centro de Investigaciones Geológicas, CONICET, Universidad Nacional de La Plata, Diagonal 113 N° 275-B1904DPK, La Plata, Argentina; Susana Adamonis [], Departamento de Ciencias Geológicas, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, IDEAN. Ciudad Universitaria Pabellón II, Intendente Güiraldes 2160-C1428EHA Buenos Aires, Argentina.  相似文献   
54.
Yates, A.M., December, 2008. Two new cowries (Gastropoda: Cypraeidae) from the middle Miocene of South Australia. Alcheringa 32, 353–364. ISSN 0311-5518.

The South Australian specimens of the cypraeids Umbilia leptorhyncha (McCoy, 1877) and Lyncina (Austrocypraea) contusa (McCoy, 1877) are re-examined. Umbilia caepa sp. nov. differs from U. leptorhyncha in its smaller size, more strongly pyriform shape, weaker and less extensive apertural dentition, plate-like columellar margin of the posterior canal and more extensive basal flanges. True U. leptorhyncha is also recorded from the Cadell Formation of South Australia, demonstrating that the two species were sympatric in the Murray Basin. The specimens originally referred to Cypraea contusa var. from the Cadell Formation have had a confusing taxonomic history and they are here named as a new species Lyncina (Austrocypraea) cadella sp. nov. The new species differs from true L. (A.) contusa in its smaller size, less extensive malleations of the dorsal surface, fewer apertural teeth and a projecting internal margin of the fossula. These two new species boost a small but growing list of species that were endemic to the Murray Basin during the middle Miocene.  相似文献   
55.
56.
A new genus with two new species, Scabolyda orientalis gen. et sp. nov. and Scabolyda incompleta sp. nov., assigned to the subfamily Juralydinae in the family Pamphiliidae are described and illustrated. They were collected from the Middle Jurassic Jiulongshan Formation and the Lower Cretaceous Yixian Formation in northeastern China. They represent the first fossil pamphiliids described from China.  相似文献   
57.
An ichnoassemblage of 10 ichnospecies is described for the first time from the Late Silurian Melbourne Formation at Studley Park, Victoria, southeastern Australia. The ichnofauna is preserved in a typical deep-water turbidite succession of alternating thin- to thick-bedded sandstone and thin- to medium-bedded mudrocks. Trace fossils observed within the study site have been assigned to three main ichnofacies. Ichnofacies 1 is best developed on the linguoid-rippled upper surface of thin sandstone beds and includes Laevicyclus, Aulichnites, Nereites, Helminthoidichnites, small Chondrites and possible Zoophycos. Ichnofacies 2 is very similar to Ichnofacies 1 in ichnospecies composition but instead contains large forms of Chondrites together with other thin burrow types usually poorly preserved and in very low abundance compared with Ichnofacies 1. Ichnofacies 3 is preserved mainly as casts on the underside of medium- to thick-bedded turbiditic sandstones, and has a very low diversity, with Planolites being the most common trace. A detailed analysis of the ichnofabrics and tiering structures of these ichnofacies suggest that Ichnofacies 1 and 3 represent ‘simple tiering’, in contrast to Ichnofacies 2, which is more characteristic of ‘complex tiering’. Despite the differences in ichnospecies composition and ichnofabrics between the three recognized ichnofacies, the collective ichnoassemblage from the study site can be assigned confidently to the Nereites ichnofacies and is, therefore, interpreted to have formed in a distal submarine fan environment of lower bathyal to abyssal depth. Further, it is possible to recognize two main subenvironments within this deep-sea setting to account for the differences between the ichnofacies. Ichnofacies 1 and 2 are interpreted to represent a typical Nereites ichnofacies located on a level basin floor subenvironment of relatively low energy conditions at the distal end of a submarine fan deposit. In comparison, Ichnofacies 3 is dominated by Planolites with rare other facies-crossing trace fossil forms, and lacks Nereites. It is, therefore, best interpreted as representing a relatively high-energy environment, possibly a distributary channel near the distal end of the submarine fan system.  相似文献   
58.
Serratognathus diversus An, Cornuodus longibasis (Lindström), Drepanodus arcuatus Pander, and eleven other less common conodonts, including Cornuodus? sp., Oistodus lanceolatus, Protopanderodus gradatus, Protoprioniodus simplicissimus, Juanognathus variabilis, Nasusgnathus dolonus, Paltodus? sp., Scolopodus houlianzhaiensis, Semiacontiodus apterus, Semiacontiodus sp. cf. S. cornuformis and Serratognathoides? sp., are described and illustrated from the Honghuayuan Formation in Guizhou, South China, concluding revision of the conodont fauna from this unit, which comprises 24 species in total. The most distinctive species in the fauna, S. diversus, consists of a trimembrate apparatus, including symmetrical Sa, asymmetrical Sb and strongly asymmetrical Sc elements. This species concept is supported by the absence of any other element types in a large collection represented by nearly 500 specimens of this species. The fauna indicates a late Tremadocian to mid-Floian age (Early Ordovician) for the Honghuayuan Formation, which was widely distributed on the Yangtze Platform in shallow water environments. Previously published biostratigraphic zonations for the Honghuayuan Formation are reviewed, and revised on the basis of our knowledge of the entire conodont fauna, supporting the establishment of three biozones, Triangulodus bifidus, Serratognathus diversus, and Prioniodus honghuayanensis biozones in ascending order. Species of Serratognathus enable correlation between Ordovician successions of South China, North China (North China Platform and Ordos Basin), Tarim Basin, and further afield into Malaysia and northwestern Australia.  相似文献   
59.
A new species of a fossil crustacean clam shrimp (Spinicaudata: Eosestheriidae) Menucoestheria wichmanni is described from the lower Upper Triassic Vera Formation (Los Menucos Complex) in Río Negro Province, southern Argentina. This discovery represents the first record of this family in the Triassic of Argentina and the southernmost record of South American Triassic ‘conchostracans’ (Spinicaudata). The new species shows close affinities with Middle Jurassic faunas from Antarctica and offers important data on the taxonomy (notably the use of ornamentation characters), palaeobiogeography (as South America hosts the oldest-known fossils of this family) and evolution of the Gondwanan faunas. Other South American eosestheriid species are tentatively recognized. Menucoestheria is hypothesized to be the ancestral form of the Triassic–Jurassic Gondwanan eosestheriids. Relationships between European and Gondwanan eosestheriids remain unresolved.  相似文献   
60.
New isolated pterodactyloid bones from the Toolebuc Formation are described. The first one consists of a complete wing metacarpal 212 mm long, representing an individual with an estimated wing span of 4 m. Small depressions on the anterior surface are present and represent tooth marks showing that this specimen was subjected to scavenging prior to fossilization. The other bone consists of a three-dimensionally preserved cervical vertebra lacking most of the neural arch. The specimens are clearly referable to the derived pterosaur clade Pterodactyloidea. Based on several features such as the position of the pneumatic foramen and the particular shape and proportions of those elements, they possibly are members of, or closely related to, the Anhangueridae. The record of the Australian pterosaurs is reviewed here and represents the known southern distributional limit for Cretaceous pterosaurs, arguing against some older ideas of a more geographically restricted range for these flying reptiles.  相似文献   
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