Foliomena Fauna (Brachiopoda) from the Upper Ordovician of Sardinia

The late Ordovician brachiopod assemblage from Sardinia is one of the youngest members of the deep-water Foliomena fauna and is characterized by the following core taxa: Christiania , Cyclospira , Dedzetina and Foliomena . The fauna also contains Epitomyonia , Leangella , Glyptorthis and Skenidioides , which are more typical of shallower-water environments during the late Ordovician but occupied deeper-water niches during the Silurian following the termination of the Foliomena fauna. The suprafamilial placement of the family Chrustenoporidae is discussed and the new species Dedzetina serpaglii and Leangella ( Leangella ) fecunda are established. In common with many mid-Ashgill Foliomena faunas the Sardinian assemblage shows significant differences from other faunal developments of this type, reflecting its geographical position and shallower water conditions than those of the classic early Ashgill Foliomena faunas. The brachiopods occur with abundant trilobites belonging to a variant of the cyclopygid fauna. The faunas developed on part of a complex of microcontinents derived from peri-Gondwana during the Ordovician.     

上扬子区奥陶纪三叶虫属Hexacopyge的新材料

描述上扬子区鄂西和湘西中及晚奥陶世桨肋虫类三叶虫Hexacopyge的 5个种 ,包括 2新种 ,即H .turbiniformis和H .yichangensis;讨论Hexacopyge的定义及其与相关属的关系。Hexacopyge在区内分布广、演化快 。     

湖北宜昌地区晚奥陶世三叶虫动物群及分带序列

从湖北宜昌黄花场和普溪河桥宝塔组剖面获得的新材料,极大地丰富了华南晚奥陶世三叶虫动物群内容,包括22属、1亚属、31种之多。新材料保存完美,很大程度上完整了有关三叶虫的形态特征。RemopleuridesamphitryonoidesLu,1975一种由于新发现了活动颊、唇瓣、胸部及尾部,证明它确实是Remopleurides的成员,排除了对该种归属的怀疑。文中建立了1新属和2新种:Pentacopygepuxiheensisgen.etsp.nov.,Lamproscutellum?limbatumsp.nov.。同时,以桨肋虫类为基础在宝塔组Nankinolithus带之下进一步划分出4个三叶虫带,从下到上依次为Pentacopygepuxiheensis间隔带,Hexacopygeyichangensis间隔带,Remopleuridesamphitryonoides延限带(普溪河段,卡拉道克中期),和Dislobosaspisguizhouensis延限带(临湘段下部,卡拉道克晚期)。     

Late Ordovician Brachiopods From The Otar Member Of The Chu-Ili Range, South Kazakhstan

Brachiopods from the Otar Member (upper Caradoc) of the Dulankara Formation, Kazakhstan, are revised. Twenty-one species are represented of which the orthoid genus Bokotorthis and strophomenoid genus Karomena are new. New species are Phaceloorthis reconditaPlaesiomys fidelisAnoptambonites kovalevskii, Karomena squalidaDzhebaglina plicata. Three ecological associations are identified, the Altaethyrella-Nalivkinia (Pronalivkinia) Association, the Ctenodonta-Sowerbyella Association and the Dinorthis Association, all living in shallow-water (BA2) environments. The fauna shows closest affinity with South China, but contains two genera only known elsewhere from Australia.     

Oldest known Dicoelosia and Epitomyonia,deep water brachiopods from the Beiguoshan Formation (Middle Katian,Upper Ordovician), Shaanxi,north China

Abstract: A diverse brachiopod fauna from a relatively deep water carbonate facies of the Upper Ordovician Beiguoshan Formation (uppermost Caradoc – lower Ashgill, middle Katian) is characterized by small shells and contains the oldest known Dicoelosia and Epitomyonia, two diagnostic taxa of deep water brachiopod palaeocommunities during the Late Ordovician and Silurian. Three new species are recognized: Dicoelosia cordiformis sp. nov., Dicoelosia perbrevis sp. nov. and Epitomyonia fui sp. nov. These pioneer forms of the family Dicoelosiidae show a relatively high degree of morphological plasticity. The shells of Dicoelosia from the Beiguoshan Formation range from the typical slender‐lobed form with a concavoconvex profile to the strongly equibiconvex, fat‐lobed morphotype that was not known previously until the late Silurian. The Beiguoshan dicoelosiids point to an important attribute of the deep water brachiopods: small generalists with high morphological plasticity, which make them ideal candidates as progenitors for the evolution of shallow water brachiopod faunas in shelf and platform depositional environments.     

STROPHOMENIDE BRACHIOPODS FROM THE CHANGWU FORMATION (LATE KATIAN, LATE ORDOVICIAN) OF CHUN'AN, WESTERN ZHEJIANG, SOUTH-EAST CHINA

Abstract:  Late Ordovician strophomenide brachiopods (superfamilies Strophomenoidea and Plectambonitoidea) from the upper Changwu Formation (mid Ashgill, late Katian) of Jianglütang, Chun'an County, western Zhejiang Province, consist of ten genera and 12 species. Five new species of three new genera are recognized: Chunanomena triporcata , Chunanomena sembellina , Cheramomena subsolana , Lateriseptomena modesta , and Lateriseptomena rugosa . The strophomenide brachiopods from the upper Katian strata described in this study and those from the border region of Zhejiang and Jiangxi provinces reported in previous work contain 16 strophomenoid and 12 plectambonitoid genera, and most of the strophomenoids are endemic to South China. Numerical analysis of well-documented late Katian strophomenide brachiopod faunas indicates a strong provincialism, characterized by the highly distinct North American province (Laurentia), the South China-Kazakhstan province, and the Avalonia-Baltica province (Wales, Belgium and Sweden). Surprisingly, the Girvan district of Scotland, which was a peri-Laurentian terrane during the Ordovician, contains a late Katian brachiopod fauna that is more closely related to the contemporaneous brachiopods of Avalonia-Baltica than to those of North America.     

Huemacaspis (Trilobita, Kerfornellinae) from the Late Ordovician of the Argentine Cordillera Oriental

The trilobite genus Huemacaspis P?IBYL and VANěK, 1980 is redescribed from well-preserved material from the Santa Gertrudis Formation (early Caradoc), Argentine Cordillera Oriental. The new species H. gallinatoensis is described and figured. Huemacaspis is widely distributed in the southern part of the Central Andean basin during the early Caradoc and it is a key taxon for the correlation of different units from the Cordillera Oriental and Sierras Subandinas of Argentina and the Cordillera Oriental of Bolivia. This taxon is one of the few records of trilobites of early Caradoc age found in the shallow shelf environments of southwestern Gondwana. Huemacaspis is accommodated within the Kerfornellinae, a subfamily otherwise known from southern Central Europe and northern Africa. The trilobite fauna from the early Caradoc of the Central Andean basin suggests a faunal exchange with the latter regions indicating the persistence of a broadly similar biogeographic pattern to that documented in earlier Ordovician times.     

陕西梁山地区宝塔组介形类

本文报道了陕西省南郑县梁山地区中奥陶统宝塔组介形类8属10种,其中包括3新属8新种。这些介形类化石的发现,为该时代地层的划分、对比增添了新的古生物依据。     

Eine neue fragliche kalkschalige Foraminif ere aus einem mittelordovizischen Geschiebe Norddeutschlands

Calcareous foraminifers were hitherto unknown from the Ordovician of Baltoscandia. From an erratic Backsteinkalk boulder of Northern Germany (Middle Ordovician) a new bodily preserved questionable species ofGlomovertella is described.Glomovertella belongs to the questionable order of foraminifers Reitlingerellida and was known hitherto only from the Lower Cambrian of Siberia and the Caradoc of Kazachstan. The members of the Reitlingerellida were, until now, only known by thin sections.     

华南贵州早奥陶世红花园组的镰箭类牙形刺

本文描述了产自华南贵州下奥陶统红花园组(桐梓红花园标准剖面,沿河甘溪剖面和贵阳黄花冲剖面)的四个镰箭类牙形刺种:Drepanoistodus sp.cf.nowlani,Paltodus sp.cf.P.subaequalis,Paltodus sp.A和Paroisto-dus sp.。D.sp.cf.nowlani为红花园组常见种,但另三种则相对稀少。在红花园组标准剖面,Paltodus sp.cf.P.subaequalis最低出现于该组底部,证实此层位为晚特马豆克期。文中详细图示了产于瑞典下奥陶统的两个带化石种:Paltodus deltifer和Paroistodus proteus,以及瑞典镰箭刺属的三个常见种:Drepanoistodus forceps,D.basiovalis和D.sp.cf.D.suberectus。通过与瑞典材料的详细对比,我们认为华南以前关于P.proteus和P.deltifer两种的记述多有误,须重新厘定。     

Biostratigraphy and palaeogeography of Late Ordovician chitinozoans from the northeastern Alborz Range,Iran

Chitinozoans were extracted from Upper Ordovician strata in the northeastern Alborz Range (Kopet Dagh Region); 31 chitinozoan species are recorded. Four successive biozones are recognised within the Ghelli Formation, viz. Tanuchitina fistulosa, Acanthochitina barbata, Armoricochitina cf. nigerica and Ancyrochitina merga biozones. Correlation of these biozones with those of the North Gondwana Domain suggests that the middle and upper parts of the Ghelli Formation range from Late Caradoc to mid Ashgill. The number of species in common with the North Gondwana Domain suggests a close relationship between Iran and North Gondwana. However, there are a number of cosmopolitan species occurring in the Ashgill. Three new species are described: Armoricochitina alborzensis, Armoricochitina iranica and Ancyrochitina persica.     

UPPER ORDOVICIAN BRYOZOANS OF THE PIN FORMATION (SPITI VALLEY, NORTHERN INDIA)

Abstract: Twenty‐nine species of bryozoans from the Upper Ordovician–Lower Silurian Pin Formation (Spiti, India) have been identified. Eight of these are new: Trematopora minima, Ulrichostylus bhargavai, Ptilodictya exiliformis, Phaenopora ordinarius, Oanduellina himalayaica, Pesnastylus? vesiculosum, Ralfina? originalis and Pinocladia triangulata. The fossil record and facies analyses of the area investigated indicate shallow‐water conditions within the subtropical–tropical realm. The distribution pattern of fossils among the Ordovician/Silurian succession on the Northern Gondwana shelf and the influence of the Late Ordovician cooling phases on marine organisms are distinctive owing to a dramatic reduction in diversity globally. As far as the bryozoan taxa of Spiti are concerned, only one (Helopora fragilis) of the 29 species was recorded above the Ordovician/Silurian boundary. Observed bryozoan communities are very similar to faunas of Laurentia, the Baltic, Siberia and southern China of early–late Ordovician age.     

Structural inversion and origin of a Late Ordovician (Trenton) carbonate buildup: evidence from the Tanglewood and Devils Hollow members, Lexington Limestone, central Kentucky (USA)

Throughout east–central United States, Lexington/Trenton limestones are largely Late Ordovician (Chatfieldian; mid-Caradoc), argillaceous, skeletal calcarenites, which are transgressive upward into Late Ordovician (late Chatfieldian–Edenian; mid-late Caradoc) shales and interbedded micrograined limestones. In central Kentucky, however, the same sequence is partially truncated by an unconformity and passes upward into a thicker, younger (Edenian; late Caradoc), regressive shoal complex of coarse calcarenites and calcirudites that is not generally typical of the Lexington/Trenton sequence elsewhere. The shoal complex is interpreted to have been a carbonate buildup and is partially bound by extant faults with basement precursors. Comparison of isopachous maps for pre- and postunconformity buildup units with basement structural lineaments suggests that the buildup is related to reactivation—and in one prominent case, inversion—of the basement structures. The coincidence of structural reactivation, inversion, and buildup development with other major regional, cratonic changes may reflect a reorganization of cratonic, far-field forces accompanying a nearly coeval reversal in the polarity of Taconic subduction.     

Taxonomy and palaeoecology of the mollusc Pterotheca from the Ordovician and Silurian of Scotland

A large sample of the bizarre bellerophontiform mollusc Pterotheca from the Upper Llandovery Wether Law Linn Formation in the Scottish Pentland Hills shows marked polymorphic asymmetry. A survival strategy that presents to a predator a mosaic of different search images is suggested to account for the marked variability of the Pterotheca morphology. Multivariate comparisons with Pterotheca mullochensis from the Llandovery of Girvan, P. simplex from the Caradoc of Girvan, P. cf. simplex from the Caradoc of the Northern Belt of the Southern Uplands and P. aff. mullochensis from the Llandovery in the Pentland Hills have helped clarify the morphological differences between these groups. A new species, Pterotheca trimerelloides , is established for the specimens from the Pterotheca beds in the Wether Law Linn Formation. □ Mollusca, Silurian, Ordovician , Pterotheca, taxonomy, palaeoecology.     

塔里木盆地晚奥陶世古海藻果实状化石及塔中油田生物母质特征

晚奥陶世良里塔格组是塔里木盆地中部油气田的主要烃源岩之一。良里塔格组有着丰富的“海草”残体。本文研究采自良里塔格组的海草的果实状化石计3新属,3新种,同时提供了一个实例,表明生物标志物与生物群之间的联系。     

Ordovician (Caradoc) Gastropoda of the Katkoyeh Formation, Kerman Province, Iran

Seven taxa of gastropods are described from the Ordovician (Caradoc) upper Katkoyeh Formation of the Kerman region, east-central Iran. Three are named species and four are under open nomenclature. The most abundant is the minute bellerophontiform Tritonophon peeli Horný, 1977, indicative of a shallow water plectonotid community. Shell material is not preserved in this species, but a small, simple bulbous protoconch is present. Two new species are Slehoferia pachyta and Nonorios kleistos, both with prominent thick-shelled conchs. Shell repair is documented in both of these forms, interpreted as a result of failed predation. Other micromorphic species occur in the samples, but only Tropidodiscus sp. and Nonorios? sp. are named. The Kerman assemblage is comparable directly with similar, closely coeval faunas in Bohemia, France, Portugal, Morocco, and Italy, corresponding with the Palaeozoic Mediterranean Province of northern peri-Gondwana.     

峡东地区上奥陶统高庙坡组球节子类及其它多节类三叶虫

系统描述湖北宜昌和秭归新滩晚奥陶世庙坡组球接子类及多节类三叶虫动物群中的１４种,分属于９属、７科、。根据化石保存状态、挤压变形以及个体发育特征,对前人所报道的产于本组的有关三叶早作了大量归并、转移和重新厘定,新的材料支持解释Telephiana longicephala的性双形现象。Ａtractopyge系首次在庙坡组中发现,以往它在三峡地区只见于临湘组。文中还将新疆的一个保留命名种Ｌonchodomas cf.yohi重新命名为Ｌonchodomas zhangi sp.nov.。     

重庆城口大塘口下奥陶统红花园组和湄潭组下部的几丁虫

文中图示和描述了重庆城口大塘口奥陶系红花园组和湄潭组下部营盘段的几丁虫计 6属, 17种。其中包括 7个未定种和 3个新种 (Conochitinadatangkouensissp. nov., C. wengxigouensissp. nov., Rhabdochitinachenk ouensesp. nov. )。讨论了几丁虫的地理和地层分布特点及其与笔石生物带的关系,阐明了红花园组和湄潭组下部营盘段不同笔石带(A. filiformis, D. bifidus和A. suecicus笔石带)中几丁虫的组合特征,并与国外同期地层几丁虫组合进行了对比。     

安徽滁州琅琊山下奥陶统弗洛阶(红花园组上部)的苔藓动物

寒武纪没有化石苔藓动物的任何记录.最老的、毫无疑问的、真正的苔藓动物,发现于我国峡东地区的下奥陶统特马豆克阶地层中.这类苔藓动物以丰富但多样性低的变口目和少量的隐口目为代表.弗洛期的一些苔藓动物,在北美,英国和波罗的海地区(俄罗斯西北部)已相继发现,这时以Ceramopora?unapensis为代表的泡孔目苔藓动物开始出现,有一定的多样性.中奥陶世初期,苔藓动物迅速崛起,古生代狭唇纲的四个目--变口目、隐口目、泡孔目和管孔目(=环口目)苔藓动物都已经有了代表.由于奥陶纪是苔藓动物发生、演化发展和辐射的重要时期,因此,奥陶纪,特别是早奥陶世苔藓动物的任何新的发现,都有重要的意义.本文描述和解释的一个新的苔藓动物群,发现于安徽滁州琅琊山弗洛阶的红花园组上部.这个苔藓动物群由变口目爱沙尼亚苔虫亚目的两个种:Dianulites hexaporites(Pander),Orbiramus grandis sp.nov.和隐口目翼网苔虫亚目的一个种:Prophyllodi-ctya putilovensis Lavrentjeva组成.尽管这个苔藓动物群在局部地区可能还是低多样性的,但就整个世界范围而言,有一定的多样性,类似于同样以变口目苔藓动物占优势的比林根苔藓动物群,后一苔藓动物群产于波罗的海以东地区(俄罗斯西北部)同时代的地层中.     

Early–Mid Ordovician Yangtzeella (Syntrophiidina, Brachiopoda) and its evolutionary significance

Abstract:  Re-examination of newly collected topotype material confirms that the type species of Yangtzeella , Y .  poloi , a widespread Early and Mid Ordovician syntrophiidine brachiopod in South China, has a finely costellate shell rather than being smooth as previously thought. Thus, the subgenus Yangtzeella ( Vadimella ) Nikitina et   al ., established on the basis of fine costellae, is invalidated. Among 15 species of Yangtzeella , five species are recognized as valid based on multivariate analyses: Y .  poloi , Y .  unsulcata , Y .  songziensis , Y .  kueiyangensis and Y .  igori , among which the type species was the oldest known. Six are synonymized: Y .  septata , Y .  reticulata , Y .  lensiformis , Y .  depressa , Y .  yichangensis and Y .  minuta . Four are rejected from Yangtzeella : Y .  extensa , Y .  similior , Y .  yohi and Y .  poloi var. minor . Regional biostratigraphy indicates that Yangtzeella first appeared in a relatively deep-water setting on the Lower Yangtze Platform (South China palaeoplate) during late Tremadoc time ( Scolopodus warendensis conodont biozone) and then expanded to the deeper Jiangnan Slope as well as to the shallower Upper Yangtze Platform. The genus experienced two episodes of heightened abundance and diversity on the Upper Yangtze Platform during late Dapingian and mid Darriwilian times, respectively. Outside South China, Yangtzeella occurs sporadically in a few microplates or terranes, such as Tarim, Chu-Ili (southern Kazakhstan) and Taurides (southern Turkey) during the Dapingian and Darriwilian. Worldwide, Yangtzeella became extinct by the end of the Darriwilian.