New Viséan and Serpukhovian ammonoids from the Verkhnyaya Kardailovka section, eastern slope of the South Urals

Viséan and Early Serpukhovian ammonoids from the Verkhnyaya Kardailovka section (South Urals, Bashkortostan) are discussed. The ammonoid assemblages include taxa that have not been previously recorded from this region and are probably connected with the open shelf settings of the eastern subregion of the South Urals. For the first time in the South Urals, we were able to recognize the succession of the ammonoid genozones Goniatites → Hypergoniatites-Ferganoceras → Uralopronorites-Cravenoceras within the same section that can be correlated with the synchronous zonations of Western Europe, North Africa, and North America. New records allow interpretation of the evolution of the family Goniatitidae in the Ural Paleocean in the terminal Viséan. Two new species, Goniatites altus sp. nov. and Platygoniatites integer sp. nov. are described.     

New Late Viséan and Early Serpukhovian ammonoids in the Verkhnyaya Kardailovka section (Eastern Slope of the South Urals)

New Late Viséan and Early Serpukhovian ammonoids are described from the Verkhnyaya Kardailovka section (South Urals, Bashkortostan). The ammonoid assemblages allow the recognition of the Hypergoniatites?Ferganoceras Genozone and a correlation with the synchronous zonations of North Africa, Spain, and China. The new species Ferganoceras constrictum sp. nov., Dombarites clemens sp. nov., and Hypergoniatites kardailovkensis sp. nov. are described.     

The Carboniferous carbonates of the Dombar Hills (western Kazakhstan) and the problem of the Viséan–Serpukhovian boundary

The Upper Viséan–Serpukhovian ammonoid-rich carbonates in the Dombar Hills (Aktobe Region, western Kazakhstan) provide an excellent opportunity to calibrate the ammonoid and conodont zonations around the base of the Serpukhovian Stage, and are important for interregional correlation. A section in the Dombar Hills spanning the Viséan–Serpukhovian boundary is measured and its fossil content is analyzed. Two ammonoid genozones (Hypergoniatites-Ferganoceras and Uralopronorites-Cravenoceras) and two conodont zones (Lochriea nodosa and Lochriea ziegleri) are recognized. The section displays a contact between the Hypergoniatites-Ferganoceras and Uralopronorites-Cravenoceras ammonoid genozones in a continuous succession and an evolutionarily early appearance of the genus Cravenoceras. The base of the Serpukhovian Stage is drawn at the level of the first appearance datum (FAD) of the conodont Lochriea ziegleri, which, as in the Verkhnyaya Kardailovka section (potential GSSP candidate, South Urals, Russia) enters within the Hypergoniatites-Ferganoceras ammonoid Genozone.     

Selection of the conodont Idiognathodus simulator (Ellison) as the event marker for the base of the global Gzhelian Stage (Upper Pennsylvanian, Carboniferous)

Studies carried out for more than 10 years by the Task Group to establish GSSPs at the base of the Moscovian–Kasimovian and Kasimovian–Gzhelian boundaries have resulted in the proposal that the level at which the conodont species Idiognathodus simulator (Ellison, 1941) first appears be selected to mark the base of the Gzhelian Stage. This expands this eastern European chronostratigraphic unit to a global scale.I. simulator (sensu Barrick et al., 2008) has been identified so far in Midcontinent and eastern North America, the Moscow and Donets basins and southern Urals of eastern Europe, and in south-central China. Correlation of this level based on this species and other conodont species can be reinforced in some areas by ammonoid and fusulinid data.     

Early Carboniferous (Mississippian) ammonoid biogeography

Cluster analyses and non-metric multidimensional scaling of ammonoid assemblages from six successive Early Carboniferous time intervals (two Tournaisian, Viséan, and Serpukhovian) show that increasing provincialism is the main biogeographic trend through the period. While the assemblages from the Tournaisian to the early Late Viséan are globally similar in the tropical occurrences, dissimilarities appear in the middle Late Viséan and become pronounced in the latest Viséan, Pendleian, and Arnsbergian. From the latest Viséan, two major biogeographic realms are recognisable. A north-western realm consists of the four North Variscan regions (Rhenish Mountains, North England, South Portugal, and Moroccan Meseta) as well as the American Midcontinent and the Antler Foreland Basin. The second realm includes the South Urals, which is the most diverse region and thus has an isolated position, as well as the Jadar Block of Serbia, the Cantabrian Mountains of Spain, the Anti-Atlas of Morocco, and the Saoura Valley of Algeria.     

A new ammonoid fauna from the Carnian (Upper Triassic) Kasimlar Formation of the Taurus Mountains (Anatolia,Turkey)

We describe a new ammonoid fauna from the Taurus Mountains of southern Turkey. The Carnian ammonoid fauna from A?a?iyaylabel is presented for the first time. Ammonoids were obtained from limestone to marl beds of an approximately 35‐m‐thick section, which presents the rare opportunity to investigate ammonoid faunas across the Lower–Upper Carnian boundary. Intense sampling near the village of A?a?iyaylabel led to the recognition of a new Lower Carnian (Julian 2) to Upper Carnian (Tuvalian 1) ammonoid fauna from the Kasimlar Formation. The genus Kasimlarceltites gen. nov. is reported for the first time from the Taurus Mountains, which represents the main faunal element and occurs as huge mass occurrence (n ? 1 million). Kasimlarceltites krystyni gen. et sp. nov., Klipsteinia disciformis sp. nov. and Anasirenites crassicrenulatus sp. nov. occur within the Lower Carnian Carbonate member (Units A–B) of the Kasimlar Formation from the Taurus Platform Units. Ammonoids described from the marls of the Tuvalian Marlstone member were deposited during a major, Tethyan‐wide climate crisis – the so‐called Carnian crisis – characterized by a demise of carbonate platforms. Based on the biostratigraphic relevance of certain ammonoid taxa described herein, the age of the analysed parts of the Kasimlar Formation is Julian 2 to Tuvalian 1. The discovery of the new ammonoid assemblages from A?a?iyaylabel substantiates the significance of Upper Triassic faunas within the Taurus Mountains and facilitates the correlation with faunal assemblages from other regions in the Tethyan Realm. The ammonoid fauna and facies indicate a general deepening from open‐platform margins, over deeper shelf settings down to an open marine‐influenced basinal environment. The tentative habitat for Kasimlarceltites gen. nov. is a shallow platform environment to upper mid‐ramp.     

滇东南泸西县上三叠统卡尼阶小凹组菊石*

本文对云南省东南部的泸西县白水镇小兴安村上三叠统卡尼阶小凹组菊石类进行了详细研究,共发现菊石9属13种,其中Anasirenites属为华南首次发现。依据各物种组合特征及其地层分布情况,自下而上识别出菊石Trachyceras multituberculatum带和Austrotrachyceras triadicum带,时代对应于晚三叠世早卡尼期的Julian 1和Julian 2。该菊石组合不仅记录了卡尼期Julian期Trachyceratidae的辐射事件,同时该菊石组合与卡尼期特提斯域和泛大洋域的菊石组合均有良好的对比性,并且为华南古地理研究提供了新的补充材料。另外,通过对剖面的岩性特征与菊石生物地层特征分析,认为在滇东南地区由于卡尼期湿润幕事件(CPE)所导致的碳酸盐岩台地消亡起始时间应为Julian 1末期略早于陆源碎屑输入的Julian 2亚期。     

New ammonoid taxa from the Lower Cretaceous Giumal Formation of the Tethyan Himalaya (Northern India)

Knowledge of the Early Cretaceous ammonoids of the NW‐Himalayas was poor until recent discoveries. Intense sampling from the Giumal Formation exposed near the village of Chikkim (Spiti Valley, Himachal Pradesh, India) led to the recognition of a new Early Cretaceous ammonoid fauna. The succession consists of arenitic sandstone interbedded with shale that was deposited by turbidity currents on an unstable shelf in the Early Cretaceous. Ammonoids have been obtained only from sandstone beds in the lower one‐third and close to the top of the c. 350‐m‐thick section. Eight new ammonoid taxa (1 genus and 7 species) are described: Sinzovia franki sp. nov. (rare), Giumaliceras giumaliense gen. et sp. nov. (abundant), Giumaliceras bhargavai gen. et sp. nov. (rare), Neocomites (Eristavites) platycostatiformis sp. nov. (rare), Cleoniceras oberhauseri sp. nov. (abundant), Australiceras himalayense sp. nov. (rare) and Deshayesites fuchsi sp. nov. (rare). Sinzovia and Deshayesites are reported for the first time from the Tethyan Himalaya. According to the biostratigraphic relevance of some ammonoid taxa described here, the age of the Giumal Formation can be constrained from Berriasian (Giumaliceras assemblage) to Aptian (Cleoniceras assemblage). The discovery of the new fauna substantiates the significance of the Giumal Formation around Chikkim and facilitates comparison with faunal assemblages from other regions in the Tethys Ocean and beyond.     

Ammonoid taphonomy, palaeoenvironments and sequence stratigraphy at the Bajocian/Bathonian boundary on the Bas Auran area (Subalpine Basin, south-eastern France)

Bas Auran, in south‐eastern France, is the candidate area for Global Boundary Stratotype Section and Point (GSSP) of the base of the Bathonian Stage (Middle Jurassic). In the Bas Auran area, upper Bajocian and lower Bathonian deposits are made up of limestone beds alternating with marls that correspond to the ‘Marno‐calcaires àCancellophycus’, below the ‘Terres Noires’ Formation. Taphonomic analyses of the successive ammonoid fossil assemblages provide new and complementary data for biostratigraphic completeness, palaeoenvironmental setting and sequence stratigraphy. Lithologic differentiation between limestone and marl intervals resulted from alternating episodes of carbonate input and starvation. Both lithologic phases may contain evidence for sedimentary and taphonomic reworking, associated with scours, that reflects low rates of sedimentation and stratigraphic condensation. Three successive types of elementary cycles resulted from increasing rates of stratigraphic condensation, sedimentary condensation and substrate stabilization during early Bathonian. The occurrence of reelaborated ammonoids (i.e. exhumed and displaced before their final burial) implies that tractive current flows or winnowing affected the burial of concretionary internal moulds. In the lower Bathonian strata, the dominance of homogeneous concretionary internal moulds of phragmocones, completely filled with sediment, is indicative of low rates of sedimentation and sediment accumulation, respectively associated with low degrees of stratigraphic and sedimentary condensation. However, at the Bajocian/Bathonian transition, hemipelagic, bed‐scale limestone–marl alternations show a maximum value of biostratigraphic completeness and there is no evidence for taphonomic condensation in the ammonoid fossil assemblages. Taphonomic analyses of the successive ammonoid fossil assemblages and taphofacies confirm the development of a deepening phase associated with sedimentary starvation, which characterizes the last episode within the deepening half‐cycle of third and second order cycles, in the Bas Auran area of French Subalpine Basin during early Bathonian.     

A new Permian ammonoid fauna of the Kobylka River (North Urals)

A new ammonoid fauna from the Artinskian-Kungurian boundary beds is described from the Kobylka River basin (North Urals). Two new species, Sakmarites tardus sp. nov. and Paragastrioceras kobylkense sp. nov., are described.     

Tithonian ammonoid biostratigraphy in eastern Himalayan Tibet

The Tithonian and Lower Berriasian sediments in the eastern Himalayas of Tibet contain an extensive sequence of ammonoid fauna. New collections in situ through the Lanongla, Pure, Gucuo and Jiapeila sections have facilitated a major revision of the ammonoid assemblages. Probably due to depositional facies segregation, the Belemnopsis galoi-bearing beds can be regarded as the oldest Tithonian sediments in which the basal Tithonian ammonoid Kossmatia is not present. The Lower Tithonian includes the Virgatosphinctes-Aulacosphinctoides and Uhligites-Aulacosphinctes assemblages; the Upper Tithonian includes the Haplophylloceras pingue, Blanfordiceras wallichi and Haplophylloceras strigile-Corongoceras-Himalayites assemblages. The Spiticeras assemblage is suggested to be from the Lowermost Berriasian. The new ammonoid assemblages at well-defined levels in Himalayan Tibet provide some crucial links for correlation with other regions of the SW Pacific domain where these ammonoid genera have been widely distributed.     

Lower Devonian reef structures in Russia: an example from the Urals

The Lower Devonian reefs of the Urals were formed in two different environmental settings: (1) the Novaya Zemlya-West-Uralian reefs were rigid organic structures that grew at a passive platform at the eastern margin of Baltica; (2) reefal limestones from the Eastern Urals developed in an island arc during a phase of volcanism. The reef belts can be traced for more than 2,500 km. The largest barrier reefs (up to 1,500 m thick) formed during the Pragian-Lower Emsian (West-Urals zone) and Emsian (East-Urals zone). They are characterized by rather uniform faunal and sedimentary features from the Arctic Ocean as south as near the Aral Lake. The Uralian reef facies was constructed mainly with algal and microbial communities (calcimicrobes and cyanobacteria) in association with low-diverse metazoan assemblages. In the Lower Devonian reefs of both regions, there are similar groups of organisms comprising some of the major taxa of reef-builders and reef-dwellers. The distinctive feature of the Lower Devonian reefs of both regions is the stromatolite-like framework structure. A clear palaeobiogeographic link is obvious between West-Uralian and East-Uralian environment settings during the Early Devonian.     

New species of Dzhulfian (Late Permian) ammonoids from the Hambast Formation of Central Iran

New ammonoid species of the genus Araxoceras (A. abarquense sp. nov. and A. iranense sp. nov.) are described from the Early Dzhulfian (Early Wuchiapingian) beds of the Hambast Formation of Central Iran (Abade). The data on the distribution of Paraceltites (Paraceltites sp.) and Vedioceras (V. umbonovarum Ruzhencev), for the first time discovered in the Dzhulfian beds of Abade, and of Eoaraxoceras are provided. The correlation of the Late Permian assemblages of ammonoids of Iran and Transcaucasia is amended.     

Evolution of the early Permian family Paragastrioceratidae (Ammonoidea) in the Urals

This paper discusses the evolution of the Early Permian ammonoid family Paragastrioceratidae in the Urals, with an emphasis on the terminal Artinskian-Kungurian stage of evolution in this group. New data on the Kungurian members of the family are discussed. Patterns of morphological and ecological changes of the Uralian paragastrioceratids are analyzed.     

Biostratigraphy of the Peri-Gondwana Cambrian trilobite fauna (northern Kerman,Iran) and correlation with other countries

Polymeroid trilobite fauna from two stratigraphic sections (Godbondar and Kuhbanan) of the Kuhbanan Formation in northern Kerman (central Iran) were studied and subjected to biostratigraphic analysis. Eleven genera and species are recognised from the latest Early Cambrian and Middle Cambrian Peri-Gondwanian successions of the study sections. The recognised fauna includes Afghanocare lategenatum, Blountia blountia, Iranoleesia sp., Iranoleesia pisiformis, Kermanella kuhbananensis, Kermanella lata lata, Kermanella lata minuta, Kermanella sp., Redlichia chinensis, Redlichia noetlingi and Redlichia sp. Based on trilobite distribution, three trilobite biozones were recognised in the study sections, namely Redlichia noetlingi biozone, Kermanella kuhbananensis biozone and Iranoleesia pisiformis biozone. The age of the study sections is late Early Cambrian to late Middle Cambrian based on the recognised trilobite biozones. The recognised late Early Cambrian trilobite assemblages (especially Redlichia and Kermanella) from northern Kerman are similar to those found from some other parts of Gondwana or Peri-Gondwana terrains (north India, Pakistan, northwestern Kashmir, Tajikistan, South Australia, South China and Afghanistan) and show affinities with fauna found in some other parts of Iran (Alborz, northern Iran; Tabas, eastern Iran; southeast Karman).     

Artinskian–Wordian antitropical rugose coral associations: A palaeogeographical approach

Recent investigations in the Urals and East-European Platform as well as study of corals collections from South Primorye (Russian Far East) and South-Eastern Pamirs have been undertaken. Antitropical rugose associations include taxa that are bounded in their distribution by the temperate zones of the Boreal and Perigondwanan realms. They occur sporadically in tropical latitudes but never form abundant and diverse communities. Antitropical associations are represented by the so-called ‘Cyathaxonia fauna’ (sensu lato), predominating in two selected stratigraphic intervals. The abrupt change of taxonomic composition from colonial to ‘Cyathaxonia fauna’ allows the separation of two assemblages: (i) mid Artinskian–Kungurian and (ii) Roadian–Wordian. The key regions for comparison are the Urals (mid Artinskian–Kungurian), Spitsbergen (Kungurian–Wordian), East-European Platform (Roadian), Texas (mid Artinskian–Kungurian), South Primorye (Wordian–Capitanian), South-Eastern Pamirs (Upper Artinskian), and the Sverdrup Basin (Wordian). The Late Artinskian fauna of the South-Eastern Pamirs and Wordian faunas of South Primorye bear features of mixed assemblages. A few models of the origination of antitropical assemblages are acceptable: (i) the convergent parallel evolution of Lophophyllidium in the Northern Hemisphere and Southern Hemisphere, (ii) a similar evolution trend developed in parallel in three geographically distant regions: Verbeekiella, Pseudowannerophyllum, and “Pseudoverbeekiella”, and (iii) immigration of some species within temperate zones caused by current circulation changes both in the Northern and Southern Hemispheres, as well as northward spreading of terranes in the Perigondwanan Realm.     

Correlation of conodont and ammonoid successions across the Viséan–Serpukhovian boundary — A review of occurrences in the South Urals,Cantabrian Mountains,western Ireland and the Rhenish Mountains

Lochriea ziegleri is the conodont species that bears the highest potential to be the index for the base of Serpukhovian. Proposed phylogenetic lineages within the genus Lochriea, particularly the lineage L. nodosa–L. ziegleri, can be confirmed by the latest studies of the succession of the respective species in sections of north-western Ireland and the Rhenish Mountains of Germany; in these regions the first occurrence datum (FOD) of L. ziegleri is in the P2a zone or the comparable Neoglyphioceras suerlandense ammonoid zone. In the Cantabrian Mountains and the South Urals, the FODs of L. ziegleri are possibly located within ammonoid zones characterized by the genera Revilloceras and early representatives of Dombarites zones with falcatoid ornament.     

Late Emsian Rutoceratoidea (Nautiloidea) from the Prague Basin,Czech Republic: morphology,diversity and palaeoecology

Abstract: Nautiloids of the superfamily Rutoceratoidea from the late Emsian (late Early Devonian) of the Prague Basin (Czech Republic) are commented upon. Species recognized include the hercoceratids Hercoceras mirum, H.? transiens, Ptenoceras proximum, P. nudum, P. minusculum and Anomaloceras anomalum, as well as the rutoceratids Adelphoceras bohemicum, Homoadelphoceras devonicans, Pseudorutoceras bolli and Goldringia? devonicans. In addition, four new species are described: Parauloceras regulare sp. nov., Roussanoffoceras chlupaci sp. nov., Otomaroceras sp. nov. and Goldringia sp. nov. Morphology and distribution patterns of Pragian and late Emsian rutoceratoid faunas from the Prague Basin are compared. They show that an increased diversity was accompanied by a higher level of specialization of rutoceratoids, which manifested itself in low abundance, increased facies dependence and greater variation in shell size during the Early Devonian. The evolution of sculpture and a contracted aperture, both regarded as protective adaptive features, was also examined, but no adaptive trend towards more pronounced sculpture and constriction of the aperture was found to have occurred in the Early Devonian. A more distinctive sculpture was, however, observed in shallow‐water assemblages of P. proximum in comparison with deeper‐water faunules, and two additional cephalopod species were examined in order to obtain comparative data. The presence of distinct sculpture patterns in coeval shallow‐ and deeper‐water assemblages suggests limited migration between them and consequently reflects some degree of territoriality in Devonian nautiloids. New data on early shell development in P. proximum are presented. During the Chote? Event, rutoceratoid generic diversity dropped dramatically, one family became extinct and the Early Devonian diversification of the group came to an end. The recovery of nautiloid faunas was slower than that of other cephalopods and associated, unrelated invertebrates. The absence of change in abundance patterns between Pragian and late Emsian rutoceratoid faunas, i.e. prior to and subsequent to ammonoid radiation, suggests that the appearance and radiation of the latter group in the early Emsian did not affect the structure of nautiloid assemblages, i.e. these two clades did not occupy the same niches.     

Ecological structure of Paleozoic ammonoids

Ecological specialization of Paleozoic ammonoid orders is discussed along with changes in the ecological structure of the ammonoid assemblages in the Early Devonian-Late Permian. Two large cycles of change in the ecological structure, Devonian and Carboniferous-Permian are recognized.     

Lower-Middle Cambrian boundary in open shelf facies of the Siberian Platform

In the Early and Middle Cambrian (of traditional usage), three broad facies belts were developed over the Siberian Platform. The lithofacies belts comprise evaporitic-carbonate, reef-shoal, and open-marine environments.Trilobites assemblages are most diverse in the open-marine lithofacies (Judoma-Olenek facies), represented especially by the Kuonamka Formation, in the eastern part of the platform. Species, genera and families of trilobites gradually increased through the Middle-Cambrian boundary interval in the Kuonamka Formation. Protolenidae dominated in the time represented by the Lermontovia Zone. In strata assigned to the Anabaraspis Zone, the protolenids disappear, the paradoxidids appear, and the diversity of dorypygids increases. The number of trilobite families increases in the Oryctocara and Kounamkites zones.Well represented in the Kuonamka formation of the eastern Siberian Platform are three levels of trilobites that have potential for global correlation. They are the Oryctocephalus reticulatus (=O. indicus latus), Oryctocephalus indicus, and Ovatoryctocara granulatus levels. The Lower-Middle Cambrian boundary in the South China correlates to the lower part of the Kounamkites Zone of the Siberian Platform.