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11.
Ghavidel-Syooki, M., Evans, D.H., Ghobadi Pour, M., Popov, L.E., Álvaro, J.J., Rakhmonov, U., Klishevich, I.A. & Ehsani, M.D., 15.5.2015. Late Ordovician cephalopods, tentaculitides, machaeridians and echinoderm columnals from Kuh-e Faraghun, High Zagros, Iran. Alcheringa 39, 530–549. ISSN 0311-5518.

Late Ordovician (Katian, uppermost Acanthochitina barbata to Armoricochitina nigerica chitinozoan zones) cephalopods, tentaculitides, machaeridians and echinoderms are documented for the first time from the southern Zagros Ranges. A low-diversity cephalopod fauna includes Geisonocerina dargazense sp. nov., Isorthoceras sp. cf. I. bisignatum (Barrande) and other undetermined orthoceratides. The presence of Late Ordovician tentaculitides in the high- to mid-latitude margins of Gondwana has been documented previously, but no examples have been described in detail. Thus, Costatulites kimi sp. nov., which currently occurs associated with brachiopods characteristic of the Svobodaina havliceki (brachiopod) Association, represents the earliest undoubted record of tentaculitides in Gondwana. Machaeridians constitute a relatively common component of the Late Ordovician benthic faunas from the Mediterranean margin of Gondwana, but no previous records on the Gondwanan Iranian-Arabian segment have been reported. Three echinoderm taxa based on dissociated columnals are documented from the Armoricochitina nigerica chitinozoan Zone, including Sumsaricystis radiatus Stukalina, Ristnacrinus sp. and Rosulicrinus rosulus Stukalina.

Mohammad Ghavidel-Syooki [] Institute of Petroleum Engineering, Technical Faculty of Tehran University, PO Box 11365-4563, Tehran, Iran; David H. Evans [], Natural England, Suite D, Unex House, Bourges Boulevard, Peterborough PE1 1NG, UK; Mansoureh Ghobadi Pour* [], Department of Geology, Faculty of Sciences, Golestan University, Gorgan, Iran; Leonid E. Popov [], Department of Geology, National Museum of Wales, Cathays Park, Cardiff CF10 3NP, UK; J. Javier Álvaro [], Instituto de Geociencias (CSIC-UCM), c/ José Antonio Novais 2, 28040 Madrid, Spain; Utkyr Rakhmonov, Kitab State Geological Reserve, 9 Ipak Yuli Street, Sakhrisabz, Uzbekistan; Inna A. Klishevich, Department of Historical Geology, Geological Faculty, St Petersburg State University, Universitetskaya Naberezhnaya 7/9, 199034 St Petersburg, Russia []; Mohammad H. Ehsani [], Institute of Petroleum Engineering, Technical Faculty of Tehran University, PO Box 11365-4563, Tehran, Iran. *Also affiliated with Department of Geology, National Museum of Wales, Cathays Park, Cardiff CF10 3NP, UK.  相似文献   
12.
Three types of byssal notch are present in Permo-Triassic Claraia-like species, i.e. Claraia-type, Pseudoclaraia-type and Claraioides-type. At present, there is no consensus in the use of the generic names. The preferred classification should be both useful in practice and compatible with the rules of taxonomy. For the genera in question, details of the byssal notch are important in assessing relationships because the morphology of this structure may closely reflect phylogenetic affinities. However, a particular feature of the notch may have great significance in one taxon but low significance in a related taxon. In order to seek the best taxonomic characters for classification of Permo-Triassic Claraia-like species, we should follow empirical evidence rather than preconceived opinions. Pseudoclaraia Zhang, 1980 should be considered a junior synonym of Claraia Bittner, 1901 Bittner, A. 1901. Über Pseudomonotis telleri und verwandte Arten der unteren Trias. Jahrbuch der geologischen Reichsanstalt Wien, 50: 559592.  [Google Scholar] because the Pseudoclaraia-type and Claraia-type byssal notches form a continuum within populations. In contrast, all known Claraioides species possess the Claraioides-type byssal notch, which is their synapomorphy, indicating monophyly. The notch is characterized by ventral enlargement due to ventral dissolution and by its contracted anterodorsal outlet due to the accretion of shell material. This is a unique character in Palaeozoic bivalves. It implies that the Claraioides byssal notch must have had a different mode of development than the other two types of byssal notch. It is thus unreasonable to place Claraioides in synonymy with Claraia. A review of the biogeographic patterns of Permo-Triassic Claraia-like species indicates that trans-oceanic dispersal of Claraia from the Boreal Realm to the rest of the world may have occurred during the latest Permian. It is possible that volcanic-winter effects triggered the trans-oceanic dispersal and the tremendous change in Permian–Triassic global biogeographical patterns.  相似文献   
13.
The Eumeralla and Wonthaggi formations (Otway and Strzelecki groups, respectively: late Hauterivian to Albian) of Victoria, Australia, have yielded diverse dinosaur faunas. Here we report a set of unassociated isolated specimens from these units including teeth, dorsal vertebrae, ribs and osteoderms of an indeterminate ankylosaurian dinosaur.  相似文献   
14.
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   
15.
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   
16.
Paleoenvironmental science has experienced a recent surge in interest and activity as concerns grow over global environmental change. Key research questions in the biotic realm of paleoenvironmental science focus on explaining climatic change at time scales of decades to centuries and understanding ecosystem responses to these changes. Biotic responses are increasingly being studied at smaller spatial scales to identify local factors that determine the sensitivity of a particular system to climatic change. These findings can then be applied to solving a variety of problems, such as setting conservation targets or testing mechanisms for observed climatic and biogeographic phenomena. Research approaches commonly used today include hypothesis testing, which has now become more sophisticated as paleoecologists and paleoclimatologists integrate with modellers. Other frameworks involve the quantitative integration of multiple proxy indicators and the use of extensive publicly available data networks to produce new datasets for paleoclimatic reconstructions and other applications.  相似文献   
17.
Bittencourt, J.S., Leal, L.A., Langer, M.C. & Azevedo, S.A.K., June 2012. An additional basal sauropodomorph specimen from theUpperTriassic Caturrita Formation, southern Brazil, with comments on the biogeography of plateosaurids. Alcheringa, 1–10. ISSN0311-5518.

We describe an additional saurischian specimen from the Caturrita Formation (Norian) of the Parana Basin, southern Brazil. This material was collected in the 1950s and remained unstudied due to its fragmentary condition. Detailed comparisons with other saurischians worldwide reveal that some characters of the ilium, including the low ventral projection of the medial wall of the acetabulum and its concave ventral margin, together with the short triangular shape of the pre-acetabular process and its mound-like dorsocaudal edge, resemble those of sauropodomorphs such as Plateosaurus and Riojasaurus. This set of traits suggests that MN 1326-V has affinities with basal Sauropodomorpha, probably closer to plateosaurians than to Saturnalia-like taxa. Previous records of this clade in the Caturrita Formation include Unaysaurus, which has been related to Plateosaurus within Plateosauridae. Alternative schemes suggest that plateosaurids include Plateosaurus plus the Argentinean ‘prosauropods’ Coloradisaurus and Riojasaurus. Both hypotheses raise biogeographic questions, as a close relationship between faunas from South America and Europe excluding Africa and North America is not supported by geological and biostratigraphical evidence. Additionally, the absence of plateosaurids in other continents suggests that the geographical distribution of thistaxon is inconsistent with the geological history of western Pangaea, and this demands further investigations of the phylogeny of sauropodomorphs or improved sampling.

J.S. Bittencourt* [sigmaorionis@yahoo.com.br] Laboratório de Paleontologia, Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes 3900, 1404901, Ribeirão Preto, SP, Brazil. Fellow FAPESP; L.A. Leal, Departamento de Ciências Biológicas, Universidade Estadual do Sudoeste da Bahia, Rua José Moreira Sobrinho, s/n, 45206-190, Jequié, BA, Brazil; M.C. Langer, Laboratório de Paleontologia, Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes 3900, 1404901, Ribeirão Preto, SP, Brazil; S.A.K. Azevedo, Laboratório de Processamento de Imagem Digital, Departamento de Geologia e Paleontologia, Museu Nacional, Universidade Federal do Rio de Janeiro, Quinta da Boa Vista s/n, 20940-040, Rio de Janeiro, RJ, Brazil. Received 29.7.2011; revised 10.10.2011; accepted 18.10.2011.  相似文献   
18.
Despite their small area, the Chatham Islands host diverse and abundant fossils. Fossil assemblages of Permian to Late Cretaceous age preserved in terrestrial to shallow marine deposits represent the only record of plants and animals that once inhabited the eastern extension of Zealandia. Lower Cenozoic sediments have yielded a shallow marine fauna, including a rich molluscan assemblage linked to the oceanic inundation of this landmass. The late Cenozoic biota documents the re-emergence of the Chatham Islands and the establishment of major oceanic currents, which meet along the Chatham Rise. This review summarizes the fossil record of the Chatham Islands and the Chatham Rise, integrating data from published and unpublished sources.  相似文献   
19.
Diverse shallow water assemblages dominated by brachiopods, molluscs, sponges and stromatoporoids, and a tabulate coral, in the Wahringa Limestone Member (Darriwilian-Gisbornian), and Yuranigh Limestone Member (Gisbornian, or early Late Ordovician) of the Fairbridge Volcanics, are documented from the northern Molong Volcanic Belt in central N.S.W. New species described include Billingsaria spissa, Shlyginia printhiensis and Sowerbyites? wahringaensis. Elements of the Wahringa Limestone Member assemblage such as Labechia banksi, Labechiella regularis, and Maclurites cf. M. florentinensis are biogeographically significant in displaying strong similarities with contemporaneous Tasmanian faunas. The brachiopods Ishimia and Shlyginia from the Yuranigh Limestone Member are recognised for the first time outside Kazakhstan and Sibumasu. The presence of the brachiopod Anoptambonites in allochthonous limestone breccia within the lower Fairbridge Volcanics provides evidence of a regionally significant hiatus of 10–15 Ma duration separating this unit from the underlying Hensleigh Siltstone, of Early Ordovician (Bendigonian) age. The sponge Archaeoscyphia?, from allochthonous limestones in the latter formation, is the oldest macrofossil yet described from the Lachlan Fold Belt in central N.S.W.  相似文献   
20.
The occupation of small islands presents particular challenges for people largely related to limited terrestrial resources and susceptibility to natural disasters. Nevertheless, the challenges and risks inherent in maintaining stable populations on small islands can be offset or overcome through the use of maritime technologies and exchange networks. The archaeology of Here Sorot Entapa rockshelter (HSE) on Kisar Island in the Wallacean Archipelago provides an unparalleled record for examining these issues in Southeast Asia. Kisar is the smallest of the Wallacean islands known to have a Pleistocene occupation record, and one of the smallest permanently inhabited today. Our results indicate that Here Sorot Entapa was first occupied in the terminal Pleistocene by people with advanced maritime technology who made extensive use of local marine resources and engaged in social connections with other islands through an obsidian exchange network. As a result, populations appear to have been maintained on the island for approximately 6,000 years. In the early Holocene occupation at HSE ceased for unknown reasons, and the site was not reoccupied until the mid-Holocene, during which time a major change in the lithic resources can be observed and the exchange network appears to have ceased.  相似文献   
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