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1.
A rich benthic and planktonic graptolite fauna is associated with encrusting rhabdopleuran hemichordates and chitinous hydrozoans in the late Arenig (Ordovician) part of the Katkoyeh Formation at Banestan, east-central Iran.

New taxa described here are the dendroid graptolites Callograptus huckriedei sp. nov. and Dictyonema bitubulata sp. nov. Other dendroid graptolites Dendrograptus sp. cf. D. flexuosus J. Hall, 1865; Acanthograptus divergens Skevington, 1963; and Thallograptus ?succulentus Ruedemann, 1904 are described. The tuboid graptolite Galeograptus sp., the rhabdopleuran hemichordates Rhabdopleura sp. aff. R. primaevus (Kozlowski, 1967) and Kystodendron sp., and the chitinous hydroid Palaeotuba sp. are also described. Graptoloid graptolites described here are Aulograptus? sp., Didymograptus incertus Perner, 1895, Undulograptus formosus (Mu & Lee, 1958), and Yutagraptus sp. cf. Y. mantuanus Riva, 1994. All but two species-level taxa are described from Iran for the first time.

The fauna is confirmed as being late Arenig or, less likely, early Llanvirn and thus probably correlates with the early part of the Darriwilian stage. It resembles the Atlantic cold water faunas in lacking isograptids and sinograptids.  相似文献   

2.
Study of the taxonomy, evolution and distribution of Tremadoc graptolites and their sequences in China and other representative sections around the world indicates that five graptolite diversity events can be recognised during the Tremadoc interval. The taxonomic validity of the suborder Graptodendroidina is advocated.  相似文献   

3.
Wang, X., Wang, J. & Zhang, J., May 2016. First appearance datum of the Silurian graptolite Oktavites spiralis, and its evolution on the northern margin of South China. Alcheringa 41, xxx–xxx. ISSN 0311-5518.

Xin Wang [], Early Life Institute and State Key Laboratory of Continental Dynamics, Department of Geology, Northwest University, Xian 710069, PR China & Research Center for Orogenic Geology, Xian Geological Survey Center, China Geological Survey, Xian 710054, PR China; Jian Wang [], Ju Zhang [], Research Center for Orogenic Geology, Xian Geological Survey Center, China Geological Survey, Xian 710054, PR China.

Graptolites represent the standard tools for biozonation and correlation of Ordovician and Silurian strata. Oktavites spiralis, one of the index graptolite species of the Telychian Age (late Llandovery, Silurian), is of great significance in biostratigraphy. However, the broad definition of the species and the lack of data on its evolutionary changes have led to controversies regarding its stratigraphic range and, consequently, to difficulties in regional correlations. Recent investigations in multiple Telychian profiles in the Ziyang–Langao area, along the northern margin of South China, reveal that the first appearance datum of Oktavites spiralis is located at the base of the Spirograptus turriculatus Zone, and its last appearance datum lies at the top of the Cyrtograptus lapworthi Zone (Telychian stage). The thecae vary markedly up-section and such change is consistent across all studied sections. This morphological change can be used as the basis for accurate stratigraphic subdivision and, hence, for effective regional correlation. In addition, this species has a wide range in population size and population density relative to other coexisting graptolite species, and can be better distinguished by using a more precise set of criteria.  相似文献   


4.
Six biostratigraphically distinct faunas based largely on trilobites and graptolites are defined from the Lower to Middle Ordovician limestone, sandstone and shale sequence of the Canning Basin. They range in age from the Tremadoc (fauna 1), through the Arenig (faunas 2, 3) to the Llanvirn (faunas 4–6).  相似文献   

5.
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   

6.
Koren', T. N., & Suyarkova, A. A., 1994:03:28. Monograptus deubeli and praedeubeli (Wenlock, Silurian) in the Asian part of the former Soviet Union. Alcheringa 18, 000–000. ISSN 0311-5518.

During the last decade the sequence and composition of the later Homerian (Wenlock) graptolite fauna has become comparatively well known in many regions of the world. A complete and detailed graptolite biozonation has been elaborated in Europe, and partly confirmed in Australia and Arctic Canada. Valuable new data have been obtained from several widely scattered areas within the Asian part of the former U. S. S. R. M. praedeubeli Jaeger (rare) and M. deubeli (common) have been found in the Homerian sequences in the Novosibirsk Islands and Novaya Zemlya, as well as in the southern Urals and the Turkestan-Alai Mountains of central Asia. In sections studied here, especially in the Alai Range, both species have well defined stratigraphic ranges in a variety of pelagic and hemipelagic facies. Their well established taxonomy based on sicular shape and thecal structure allows their recognition in material of different preservation. They belong to a single phylogenetic line and can be used as important biostratigraphic markers for interregional correlation, especially considering the distinct differences in the composition of associated monograptids. Thus, members of the Pristiograptus idoneus—Lobographu? claudiae lineage parallelling the development of M. praedeubeli and M. deubeli in the Homerian of central Asia, Australia, Arctic Canada and Arctic Russia are unknown from European and northern African sections.  相似文献   

7.
Muir, L.A., Zhang, Y.-D. & Lin, J.-P. 2012. New material from the Ordovician of China indicates that Inocaulis is a graptolite. Alcheringa 37, 558–559. ISSN 0311-5518.

The problematic Early Palaeozoic fossil Inocaulis has been regarded as an alga, a graptolite and a hydroid by different authors. A new specimen from the Ordovician (late Darriwilian) of Guizhou Province (China) shows fusellar banding, confirming that it is a benthic graptolite.

Lucy A Muir [lucy@asoldasthehills.org], Yuan-dong Zhang [ydzhang@nigpas.ac.cn], Jih-Pai Lin [jplin@nigpas.ac.cn] (corresponding author), State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, No. 39 East Beijing Road, Nanjing 210008, PR China. Received 13.12.2012; revised 10.5.2013; accepted 13.5.2013.  相似文献   

8.
9.
Abstract

Canzone d'autore is an indigenous expression that has no precise equivalent in other languages. Its social use identifies a genre of popular song that presuppose the existence of an ‘autore’ taken in its most vigorous sense, meaning a ‘creator’, an ‘artist’– but how did this claim to artistry originate? How did it insinuate itself into the world of song, a genre that by definition belongs to the realm of what is traditionally called in Italian ‘musica leggera,’ with unmistakably pejorative connotations? In this essay, I will put forward a sociological interpretation of the genesis of the canzone d'autore, using as a strategic conceptual device the idea of cultural trauma. The traumatic event that I propose to explore, making use of this concept and its analytical machinery, is the suicide of the singer-songwriter Luigi Tenco during the seventeenth San Remo ‘Festival della Canzone’ (‘song festival’) – that is the best-known, most controversial, and most influential single event in the field of Italian ‘musica leggera’, an annual event regularly attended every year – via radio, television, or audience participation – by millions of Italians. Through a reconstruction of that suicide and above all of the public and dramatic events that followed in response to it, the paper examines the social process that transformed an individual tragedy into a collective, social drama, a process that not only produced a new musical classification, but also a new cultural and aesthetic category.  相似文献   

10.
Early to Middle Tournaisian conodont faunas with Siphonodella from ten sections in eastern Australia, between Gloucester in New South Wales and Rockhampton in Queensland, may be referred to the following ‘standard’ zones; 1 sulcata, 2 upper duplicata, 3 sandbergi, 4 lower crenulata and 5 isosticha-upper crenulata, in ascending order. In eastern Australia the first occurrences of Gnathodus cuneiformis, G. delicatus, G. typicus and Protognathodus cordiformis, near the base of the lower crenulata zone, are significantly earlier than in Europe and North America. Consequently the base of the isosticha-upper crenulata zone in eastern Australia is defined by the first appearance of G. punctatus rather than that of G. delicatus. On the present evidence it is difficult to reconcile some brachiopod and conodont occurrences in the Early-Middle Tournaisian of eastern Australia.

Seventeen discrete conodont species are discussed, four of which are described informally: Dinodus sp. nov. A, Dinodus sp. nov. B, Pinacognathus sp. nov. A, and a species of Siphonodella transitional between S. cooperi and S. crenulata.  相似文献   

11.
Hadi Jahangir, Mansoureh Ghobadi Pour, Alireza Ashuri & Arash Amini, December 2015. Terminal Cambrian and Early Ordovician (Tremadocian) conodonts from Eastern Alborz, north-central Iran. Alcheringa ##, ###-###. ISSN 0311-5518.

Uppermost Cambrian (Furongian) and Lower Ordovician (Tremadocian) deposits of eastern Alborz in northern Iran contain several successive low- to moderate-diversity conodont associations including 13 genera and 19 species of euconodonts, paraconodonts and protoconodonts, which define six biozones: 1, the Proconodontus muelleri; 2, Eoconodontus notchpeakensis; 3, Cordylodus andresi; 4, Cordylodus proavus; 5, Paltodus deltifer; and 6, Paroistodus proteus zones. With the exception of Cordylodus andresi, which is otherwise known from Baltoscandia and from the Oaxaquia terrane (Mexico), all index-taxa are geographically widespread, allowing long-range correlation within the Cold Domain or the North Atlantic Province, and in particular with Baltica. Invasion of euconodonts in the Alborz region, defined by the first occurrence of Proconodontus muelleri, coincides closely with a steady rise in sea level and termination of carbonate sedimentation, whereas the transition from the Proconodontus muelleri to Eoconodontus notchpeakensis zones occurs during a highstand interval unlike in Laurentian sequences. The interval corresponding to the Cordylodus andresi and Cordylodus proavus zones, and the transition from the Paltodus deltifer to Paroistodus proteus zones coincided with unstable sea levels and the formation of shoal complexes. The lower boundary of the Floian Stage can be provisionally placed slightly below the first documented occurrence of Acodus sp. cf. A. kechikaensis, somewhat below the second unit of andesitic lava flows in the Simeh-Kuh section.

Hadi Jahangir [] and Alireza Ashuri [] Department of Geology, Faculty of Sciences, Ferdowsi University, Azadi Square, Mashhad 91775-1436, Iran; Mansoureh Ghobadi Pour* [; ] and Arash Amini [], Department of Geology, Faculty of Sciences, Golestan University, Gorgan 49138-15739, Iran. *Also affiliated with Department of Geology, National Museum of Wales, Cathays Park, Cardiff CF10 3NP, UK.  相似文献   


12.
Muir, L.A. & Botting, J.P., December, 2007. Graptolite faunas and monaxonid demosponges of the Cyrtograptus lundgreni event (late Wenlock, Silurian) interval from the Orange district, New South Wales. Alcheringa 31, 375-395. ISSN 0311-5518.

Three monograptid and five retiolitid graptoloids, and one species of sponge, are described from late Wenlock sections (Cyr. lundgreni and Co. ludensis biozones) at Spring Creek and Wallace Creek, near Orange, New South Wales, Australia. The sponge Janussenia orangense gen. et sp. nov. is the first monaxonid demosponge to be described from the Australian Silurian. An object containing broken Testograptus testis, and interpreted as the faecal pellet of a predator or scavenger on graptoloids, is described.

Lucy A. Muir [l.muir@nhm.ac.uk], Department of Palaeontology, Natural History Museum, Cromwell Road, London SW7 5BD, UK. Joseph P. Botting [joe@asoldasthehills.org], 2C Roslyn Close, Mitcham CR4 3BB, UK. Received 28.4.2006; Revised 10.10.2006.  相似文献   

13.
Taxonomic restudy of Early Darriwilian graptolites from the Yangtze region, Chiadam and Alxa, has enabled a precise correlation of the Undulograptus austrodentatus Zone (including two subzones) across the three regions, and with the Darriwilian GSSP at Huangnitang in the Jiangshan-Changshan-Yushan (JYC) area. Based on specimens from 17 localities in the Yangtze region, the Exigraptus clavus and Undulograptus austrodentatus zones are recognised as replacements respectively of the Undulograptus sinodentatus (Lower) and U. austrodentatus (Upper) zones of Mu et al. (1979). The U. sinicus Subzone, the upper subzone of the U. austrodentatus Zone, is also recognised from the Sichuan-Guizhou area of the Yangtze region. Two subzones of the U. austrodentatus Zone have also been identified from the Chiadam region with more diverse graptolite fauna. The U. austrodentatus Zone fauna also occurs in the Alxa region. A general pattern of changing graptolite diversity from platform through basinal slope to deep basin is proposed, based on early Darriwilian bio- and lithofacies changes from the Yangtze Platform through the Jiangnan belt to the Zhujiang basin. The graptolite diversity increased with water depth and more off-shore setting. Key graptolite species are illustrated.  相似文献   

14.
On the basis of representative collections made from seven measured sections in western Hubei and Hunan, four early Llanvirn and five late Llanvirn-early Caradoc trilobite biofacies are distinguished along a bathymetric gradient from shallow to deep outer shelf. The diversity and relative abundance of mesopelagic cyclopygids gradually increased southwards or seawards. According to the facies association exhibited in the region, the upper limit of living depth for different forms is inferred as follows: 1) more than 70 m (M. (Microparia)); 2) less than 100 m (M. (Quadratapyge), Pricyclopyge, Aspidaeglina); 3) at approximately 100 m (Cyclopyge); and 4) more than 100 m (Symphysops, Psilacella). Benthic forms were absent in the deep outer-shelf basin because of stagnant conditions. In shallower sites of the outer shelf, genera of nileids in the carbonate facies and raphiophorids in the clastic facies were relatively abundant, but some endemic forms, such as the asaphid Birmanites and remopleuridid Hexacopyge, became dominant during the late Llanvirn-early Caradoc. Rorringtoniids are mainly associated with deeper outer-shelf facies. Panderia is common in an early Llanvirn nileid fauna at Yichongqiao, Cili area, and may well indicate development of shelf carbonate buildups. A transgressive event is suggested by the sudden appearance of rich Cyclopyge in the early Caradoc at Jiuxi, Changde.  相似文献   

15.
Ordovician graptolite-bearing strata in eastern Yunnan were deposited in nearshore, shallow-water environments. Graptolites are systematically described from three sections through the Hungshihyen Formation in eastern Yunnan Province, China: (1) Hongshiya section near Ercun village, Kunming; (2) Liujiang section, Luquan; and (3) Guihuaqing Reservoir section, Luquan. The graptolite fauna, characterized by the predominance of deflexed forms, includes ten species in two genera: Baltograptus turgidus (Lee), B. varicosus (Wang), B. yunnanensis (Li), B. calidus (Ni), B. enshiensis (Ni), Baltograptus sp. cf. B. deflexus (Elles & Wood), Baltograptus sp. cf. B. bolivianus (Finney & Branisa), Baltograptus sp. A, Baltograptus sp. B and Corymbograptus v-fractus minor (Li). A detailed morphological study of these southern Chinese graptolite faunas suggests that Baltograptus wudingensis (Li) is a junior synonym of B. turgidus (Lee); Baltograptus kunmingensis (Ni) is a junior synonym of B. varicosus (Wang); and Baltograptus triangulatus (Ni) is a junior synonym of B. yunnanensis (Li). The B. varicosus Biozone is newly recognized within the middle part of the Hungshihyen Formation, replacing the former Didymograptus deflexus Biozone. This interval is well correlated to the Baltograptus jacksoni Biozone in Britain, the Tetragraptus akzharensis, ‘Baltograptus cf. deflexus’ and Didymograptus bifidus (lower part) biozones in NW Argentina (eastern Cordillera), and the Acrograptus filiformis and Didymograptellus eobifidus biozones in northern Guizhou, South China. Accordingly, the interval is of mid-Floian age, rather than late Floian as previously proposed.  相似文献   

16.
In this paper, we argue that beyond understanding nations as imagined communities, the metaphor of an ‘imagined family’ or ‘filial community’ is a more useful concept towards understanding links between gender and nationhood as family relations in four ways: (1) providing a clear, hierarchical structure; (2) prescribing social roles and responsibilities; (3) being linked to positive affective connotations; and (4) reifying social phenomena as biologically determined. In order to empirically substantiate our claim, we will explore the prevalence and use of family metaphors in a key symbol of nationhood discourses. Through a qualitative analysis of national anthems as ‘mnemonics of national identity’, we demonstrate the widespread presence of family metaphors, discussing how they reproduce ideas of family and gender. Finally, we discuss how the ‘imagined family’ as present in anthems and other forms of national representation could inform future studies of nationalism and national politics.  相似文献   

17.
This article considers the presence of three late-Victorian actresses (Mrs Patrick Campbell, Eleonora Duse, and Sarah Bernhardt) in the work of James Joyce. The first appears in Joyce’s short story ‘A Mother’ (Dubliners). The strong influence of the other two is also detectable in the characterization of Ulysses’ heroines, Gerty MacDowell and Molly Bloom, and in a seminal text of late modernism, Finnegans Wake. In ‘A Mother’, Joyce’s attention to the importance of fashion on the stage and to poor working conditions for female performers calls to mind the career of Mrs Patrick Campbell. In Ulysses, Gerty’s performance in ‘Nausicaa’ recalls the techniques of the Ibsenian actress Eleonora Duse, known especially for her blushing; I argue that, given this famous skill and Joyce’s fascination with her, Duse directly informs Gerty’s characterization. Finally, Molly Bloom’s repertoire of dramatic references, including Trilby, Lillie Langtry, Sarah Bernhardt, publicity photographs, and Pineroticism, suggests Joyce’s immersion in a late-Victorian dramatic world. After sketching these connections in detail, I show that his interest in these actresses encourages scholars to continue to question the validity of traditional periodization boundaries. I end by arguing that the appearance of these actresses in these examples of early, high, and late modernism indicates the cultural richness of the long nineteenth century for Joyce, which continues throughout modernism’s successive phases.  相似文献   

18.
Ni Yunan & Cooper, R. A., 1994:03:28. The graptolite Glossograptus Emmons and its proximal structure. Alcheringa 18, 161–167. ISSN 0311-5518.

New specimens of Glossograptus acanthus from the Ningkuo Shale of China, preserved in relief, help to resolve the much debated problem of the structure of Glossograptus. A model for the proximal structure of the genus is proposed, based on the new material and on Finney's (1978) Athens Shale specimens. The model confirms that Glossograptus has homologous structure and development with Pseudisograptus, and isograptid development type is primitive for the group containing both genera. A cladogram is presented in which the suborder Glossograptina Jaanusson (with families Glossograptidae and Cryptograptidae) together with family Corynoididae Bulman are subsumed within a redefined family Glossograptidae.  相似文献   

19.
Three Santacrucian borhyaenoids, Cladosictis patagonica, Pseudonotictis pusillus and Sipalocyon gracilis, are analyzed from a functional-adaptive perspective. Five extant placentals and one marsupial model are also examined in order to interpret the locomotor adaptations of these fossils. Pseudonotictis pusillus is the smallest of the Santacrucian borhyaenoids and is known from fragmentary remains; from its small size, dental specializations and elbow anatomy, this species was certainly not far ecologically from an extant weasel. The postcranium of Sipalocyon gracilis, although poorly known, suggests climbing capabilities, and the pseudo-opposable pollex indicates skilful manipulative behaviour. Cladosictis patagonica was an active predatory form, short-legged and able to climb, although it was a less specialized arboreal form than the contemporaneous Prothylacinus patagonicus; the proportions of its limbs recall that of a living South American marten, the tayra. The pseudo-opposable pollex of Cladosictis, as in Sipalocyon, indicates skilful manipulative behaviour.  相似文献   

20.
Forty-two conodont species are documented from the Liuxia, Shijiatou and Jingshan formations in Zhejiang Province of southeast China, located palaeogeographically on the Jiangnan Slope offshore to the Yangtze Platform. From these faunas, eight successive conodont biozones of Tremadocian to middle Floian (Early Ordovician) age are recognized, including the Cordylodus lindstromi Biozone, Cordylodus angulatus Biozone, Chosonodina herfurthi Biozone, Paltodus deltifer Biozone, Paroistodus proteus Biozone, Triangulodus bifidus Biozone, Serratognathus diversus Biozone and Prioniodus elegans Biozone. Several zonal index species of the Baltoscandian succession—Paltodus deltifer, Paroistodus proteus and Prioniodus elegans—are described and illustrated in detail for the first time from South China. Co-occurrence of P. proteus and Serratognathus bilobatus in several samples below the appearance of P. elegans also confirms correlation of the S. diversus Biozone (basal Floian) with the upper P. proteus Zone of the Baltoscandian succession. These Zhejiang faunas are dominated by pandemic forms, and are similar to those of the Open-Sea Realm elsewhere, inhabiting deep, offshore environments.  相似文献   

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