A Wuchiapingian (Late Permian) brachiopod fauna from an exotic block in the Indus–Tsangpo suture zone, southern Tibet, and its palaeobiogeographical and tectonic implications

A brachiopod fauna including 19 species of 17 genera from an exotic block in the Indus–Tsangpo suture zone in southern Tibet is described and illustrated. The brachiopod fauna is dominated by Martinia elegans and two new taxa: Jinomarginifera lhazeensis gen. et sp. nov. and Zhejiangospirifer giganteus sp. nov. The fauna is closely comparable with those from the middle and upper parts of the Wargal Formation and the Chhidru Formation in the Salt Range of Pakistan, the Chitichun Limestone in southern Tibet, and the Basleo area of West Timor, and these correlations suggest a Wuchiapingian age. The fauna exhibits substantial links with both peri–Gondwanan and Cathaysian faunas, which may imply that it is a seamount biota originally located in the southern margin of the Neotethys during the Late Permian, and was later (in the early Cenozoic) displaced and became sandwiched into younger marine deposits in the collision process between India and Eurasia.     

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.     

贵州安顺募役剖面晚二叠世腕足动物群落及其生态特征*

本文对贵州募役剖面长兴期腕足动物群进行了系统分类鉴定和古生态分析,发现其与前人所报道的华南同时期腕足动物群存在着显著的差别,以Spiriferellina为绝对优势属,包含少量华南长兴期的常见分子,如Fusichonetes、Araxathyris和Peltichia等。募役剖面的腕足类化石主要产自碎屑岩层位,与华南同期碎屑岩相剖面的腕足动物群落相比,该动物群中的优势分子个体较大、壳体较厚且发育较粗大的壳疹,这可能与长兴期募役剖面动物群所处的特殊栖息地环境(浅水碳酸盐岩台地与深水硅质碎屑岩盆地之间的过渡地带)有关。二叠纪末期大规模的火山作用导致水体中碎屑物质含量增加,影响腕足类的滤食效率,而募役剖面清澈、水动力弱的水体环境,为滤食性的腕足动物提供了有利的环境条件。最后,通过与华南长兴期不同沉积相区腕足动物群落(六枝剖面、稻堆山剖面、中寨剖面、新民剖面、马家山剖面和仁村坪剖面群落)的对比分析,发现募役剖面腕足动物群与毗邻的六枝剖面腕足动物群在属级组成上的相似度较高,且过渡岩相栖息地环境下的腕足动物群在生物灭绝事件前也呈现出高优势度、低均匀度的群落结构特征,指示海洋底栖生物群落已经先于二叠纪末期生物集群灭绝事件出现了早期危机信号。     

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.     

LATE ORDOVICIAN BRACHIOPODS FROM THE DULANKARA FORMATION OF THE CHU-ILI RANGE, KAZAKHSTAN: THEIR SYSTEMATICS, PALAEOECOLOGY AND PALAEOBIOGEOGRAPHY

Abstract:  Brachiopods from the late Ordovician (late Caradoc) Dulankara Formation of the Chu-Ili Range, Kazakhstan, are reviewed. Those from the upper two members of the formation, the Degeres and Akkol members, are systematically described. New genera from the Dulankara Formation are Nikitinamena (Plectambonitoidea: Leptellinidae), with type species Nikitinamena bicostata sp. nov., and Weberorthis (Orthoidea: Plectorthidae), with type species Mimella brevis Rukavishnikova. Another new genus is Glyptomenoides (Strophomenoidea: Glyptomenidae), with type species Rafinesquina girvanensis Salmon from the Caradoc of Girvan, Scotland. Other new species from the Dulankara Formation are Holtedahlina orientalis , Platymena tersa , Christiania proclivis , Leangella ( Leangella ) paletsae , Metambonites subcarinatus , Ogmoplecia nesca and Plectorthis licta . The ecology and assemblages of all three members of the Dulankara Formation are identified or reviewed, and their palaeogeographical significance assessed: the Chu-Ili Terrane (on which the Dulankara Formation was situated during the Ordovician) formed part of the relatively low-latitude peri-Gondwanan complex of terranes, and was probably not far from North and South China. The faunal links suggested between the Dulankara brachiopods and contemporary faunas from Australia are now perceived to be weaker than previously thought.     

西藏晚白垩世晚Campanian期至早Maastrichtian期菊石群——中国最年轻的菊石群

记述产自西藏南部仲巴县的一个中国目前所知最年轻的菊石群 ,含 2科 4属 6种 ,其中 4新种。据菊石群面貌和它们所产出的层位可以划分出上、下两个组合带 :上部Pachydiscuscf.hidakaensis Libycoceraszhongbaense组合带 ;下部Manambolitescujiangdingensis M .pivaeteaui组合带。产菊石的曲贝亚组的下段和上段的中、下部(82F5 0及其以下层位 )为晚Campanian期 ,上段上部 (即 82F5 2及其以上层位 )为早Maastrichtian期。     

Early Ordovician bivalves from Dali, West Yunnan, China

A bivalve fauna of Early Ordovician (late Arenig) age is described from the Hsiangyang Formation of the eastern part of West Yunnan, China. The fauna contains elements in common with Early Ordovician faunas of southern Gondwanan areas such as the Montagne Noire and Morocco and with those of Avalonia, together with several previously undescribed taxa. The following taxa are new: Biseriodonta simplex gen. et sp. nov.; Glyptarca sinensis sp. nov.; Trigonoglyptarca magna gen. et sp. nov.; Erhaiconcha xiangyangensis gen. et sp. nov.; Fasciculodonta impressa gen. et sp. nov.; Yunnanoredonia laevis gen. et sp. nov.; Daliella gen. nov.; Goniophorina ( Goniophorina ) contracta sp. nov.; Haidongoconcha radialis gen. et sp. nov.; Eopterinea aequiconcha gen. et sp. nov. The bivalve fauna includes the most diverse glyptarcid fauna and the earliest nuculanid and paracyclid known hitherto.   Eastern West Yunnan belonged to the Indochina terrane and it is concluded that the bivalve fauna represents a high-latitude assemblage and that the Indochina terrane should be considered a component part of the Peri-Gondwanan continent in the Ordovician; its bivalve faunas contrast with those of neighbouring terranes which have affinities with those of lower latitudes.     

EARLY CAMBRIAN BRACHIOPODS FROM NORTH-EAST GREENLAND

Abstract:  A diverse assemblage of late Early Cambrian brachiopods is described from the Bastion and Ella Island formations of North-East Greenland. The fauna includes nine species, representing all three extant brachiopod subphyla in addition to the stem group brachiopod Mickwitzia cf. occidens . Four linguliforms: Eoobolus priscus , Botsfordia caelata , Micromitra bella , Vandalotreta sp., three rynchonelliforms: Obolella crassa , Kutorgina reticulata , and an unidentified chileid plus a possible craniiform species occur. The fauna shows similarities to late Early Cambrian (Dyeran Stage) brachiopod faunas of eastern Canada and the United States, but also to faunas from the late Early Cambrian (Botomian–Toyonian equivalent) of Australia, Antarctica and Siberia.     

Lopingian (Late Permian) brachiopods around the Wuchiapingian-Changhsingian boundary at the Meishan Sections C and D, Changxing, South China

The strata below the defined Wuchiapingian-Changhsingian boundary GSSP are mostly covered and obscured by faulting at the Meishan Section D. Therefore, it is very difficult to collect fossils there. After an intensive excavation at Meishan Section C, a diverse fauna based on high-resolution biostratigraphy comprising brachiopods, ammonoids, conodonts, fusulinids and small foraminifers were found. Among these fossils, brachiopods are the most dominant. Eleven species of 10 genera based on more than 1300 specimens are identified. This brachiopod fauna is of late Wuchiapingian-Changhsingian of Lopingian (Late Permian) in age as well constrained by the associated ammonoid Pseudogastrioceras sp., Jinjiangoceras and Konglingites sp., the fusulinid Palaeofusulina and the conodont lineage from C. longicuspidata to C. wangi. In terms of the changes of brachiopod fauna composition around Wuchiapingian-Changhsingian boundary, it clearly indicates a continuous transgression from the upper part of the Lungtan Formation to the lower part of the Changhsing Formation. A new species, Neochonetes (Huangichonetes) meishanensis, is described and some other species are discussed based on the new collection from Meishan Sections C and D.     

Early Devonian (Lochkovian) trilobites and brachiopods from the west Balkhash Region,Kazakhstan and their significance for regional terrane dynamics

A moderately diverse Early Devonian (Lochkovian) trilobite and brachiopod association has been recovered from the lower part of the volcano-sedimentary Shakshagaily Formation, exposed on the western side of Lake Balkhash in central Kazakhstan. Its discovery demonstrates the presence of Lower Devonian marine deposits in the region. The trilobite assemblage includes representatives of six genera: the dalmanitid Kasachstania alperovichi nov. sp. is the dominant taxon, with other components being Ananaspis?, Leonaspis?, Maurotarion, Trimerus (Edgillia), and Warburgella. Associated brachiopods include species of Glossoleptaena, Leptaena, Protolepstostrophia, Pseudostrophochonetes, and Resserella. Whilst a significant proportion of these taxa show distinct links with the contemporaneous trilobite and brachiopod faunas of the north Balkhash Region, the occurrence of Trimerus (Edgillia) aff. kinglakensis Gill, 1949 suggests a possible link with the Lochkovian trilobite fauna of the Australasian sector of Gondwana. The west Balkhash Region preserves an extensive record of late Silurian to Early Devonian island arc volcanism, slope-rise sedimentation and olistostrome formation, which has invariably been ignored in models favouring early amalgamation of the Kazakhstanian terranes into a single continent by the end of the Ordovician.     

The late Sandbian – earliest Katian (Ordovician) brachiopod immigration and its influence on the brachiopod fauna in the Oslo Region, Norway

Bulk samples of brachiopods from the middle and upper parts of the Arnestad Formation and the entire Frognerkilen Formation in the Oslo Region demonstrate major vertical changes in the Sandbian to Katian amphicratonic fauna of this part of the Baltic Province. The main influx of new taxa occurred in the upper part of the Arnestad Formation (uppermost Sandbian), and in the succeeding Frognerkilen Formation (basal Katian). Faunal change is initially reflected in an increase in diversity and not as a replacement of the previously incumbent genera, which remain throughout the studied sequence. The majority of the new genera migrated from the East Baltic Region or through this region from Avalonia, while the marginal Laurentian taxa first occupied the Scandinavian part of Baltica. Six taxa migrated from Laurentia, three from Avalonia, two from Gondwana and one apparently originated on the South China palaeoplate. The faunal shifts and immigration of brachiopods appear to have been in response to an initial transgression together with the movement of Baltica into more warm temperate latitudes, but the diverse faunas developed both against a background of subsequent regression and in response to an offshore shift of biofacies. The new amphicratonic fauna was thus generated by faunal shifts from elsewhere in the Baltic Province to the marginal environments of the Oslo Region together with more exotic elements from neighbouring continents and microcontinents.     

An ecologically mixed brachiopod fauna from Changhsingian deep-water basin of South China: consequence of end-Permian global warming

The Late Permian Shaiwa Group of the Ziyun area of Guizhou, South China is a deep-water facies succession characterized by deep-water assemblages of pelagic radiolarians, foraminifers, bivalves, ammonoids and brachiopods. Here we report 20 brachiopod species in 18 genera from the uppermost Shaiwa Group. This brachiopod fauna is latest Changhsingian in age and dominated by productides. The palaeoecologic and taphonomic analysis reveals that the brachiopod fauna is preserved in situ. The attachment modes and substratum preference demonstrate that the Shaiwa brachiopod fauna comprises admixed elements of deep-water and shallow-water assemblages. The presence of the shallow-water brachiopods in the Shaiwa faunas indicates the involuntary settlement of shallow-water brachiopods. The stressed ecologic pressure, triggered by warming surface waters, restricted ecospace and short food sources, may have forced some shallow-water elements to move to hospitable deep-water settings and others to modify their habiting behaviours and exploit new ecospace in deep-water environments. We infer that the end-Permian global warming and subsequent transgression event may have accounted for the stressed environmental pressure in the shallow-water communities prior to the end-Permian mass extinction.     

Brachiopods from the Jurassic (Callovian) of Hamakhtesh Hagadol (Kurnub Anticline), Southern Israel

The Callovian Zohar and Matmor formations in the Negev, southern Israel, consisting of marls, shales and limestones, have yielded 13 brachiopod species (2 rhynchonellids, 11 terebratulids), referred to 12 genera, of which one genus and five species are new: Apatecosia inornata, Bihenithyris mediocostata, Digonella boylani sp. nov., Dissoria bretti sp. nov., Burmirhynchia jirbaensis, Kutchithyris landeri sp. nov., Pleuraloma triangulatum, Polyplectella debriani gen. et sp. nov., Ptyctothyris daghaniensis, Somalirhynchia africana, Striithyris saudiarabica, S. telemi sp. nov., and Zeilleria sp. The brachiopods described herein from Hamakhtesh Hagadol (Kurnub Anticline) comprise a fauna located at the northernmost part of the Indo-African Faunal Realm within the Jurassic Ethiopian Province.     

Ordovician radiolaria and conodonts from the peri-Gondwanan Karatau-Naryn microplate (Sarydzhaz, eastern Kyrgyzstan)

Cambrian-Ordovician sedimentary sequences crop out extensively in the area surrounding the Sarydzhaz River, a remote mountainous region situated in the eastern part of Kyrgyzstan. These sequences, composed essentially of fine siliciclastic lithologies, were deposited on a passive margin of the peri-Gondwanan Karatau-Naryn microplate. Palaeontological constraints for the age of these sequences are rare. Recent efforts of geological mapping in the area discovered reasonably well-preserved radiolarian and conodont faunas. The occurrence of conodonts was mentioned previously, but no taxonomic details were ever reported. Two conodont assemblages are identified from the Oldzhobai Formation; the first is dominated by Paracordylodus gracilis, which can be correlated with the upper Tremadocian to lower Floian; the second assemblage is more diverse and characterized by Prioniodus elegans, suggesting a mid Floian age. This is the first discovery of Ordovician Radiolaria from Kyrgyzstan. In spite of its rather moderately good to poor preservation, the fauna is interesting in many respects, especially due to the presence of a new radiolarian species (Inanigutta (?) kyrgyza nov. sp.). The latter is easily identifiable by the distinctive pore pattern of its cortical shell and has therefore the potential to become in the future a biostratigraphic marker species.     

Early Cambrian organophosphatic brachiopods from the Xinji Formation,at Shuiyu section,Shanxi Province,North China

Abundant and diverse small shelly fossils have been reported from Cambrian Series 2 in North China, but the co-occurring brachiopods are still poorly known. Herein, we describe seven genera, five species and two undetermined species of organophosphatic brachiopods including one new genus and new species from the lower Cambrian Xinji Formation at Shuiyu section, located on the southern margin of North China Platform. The brachiopod assemblage comprises one mickwitziid (stem group brachiopoda), Paramickwitzia boreussinaensis n. gen. n. sp., a paterinide, Askepasma toddense Laurie, 1986, an acrotretoid, Eohadrotreta cf. zhenbaensis Li and Holmer, 2004, a botsfordiid, Schizopholis yorkensis (Holmer and Ushatinskaya in Gravestock et al., 2001) and three linguloids, Spinobolus sp., Eodicellomus cf. elkaniiformis Holmer and Ushatinskaya in Gravestock et al., 2001 and Eoobolus sp. This brachiopod assemblage suggests a late Age 3 to early Age 4 for the Xinji Formation and reveals a remarkably strong connection with coeval faunas from East Gondwana, particularly the Hawker Group in South Australia. The high degree of similarity (even at species level) further supports a close palaeogeographic position between the North China Platform and Australian East Gondwana during the early Cambrian as indicated by small shelly fossil data.     

ORDOVICIAN (ARENIG–CARADOC) SYNTROPHIIDINE BRACHIOPODS FROM THE EAST BALTIC REGION

Abstract:  Syntrophiidine brachiopods are a rare and poorly known component of Ordovician Baltoscandian faunas. They appear in the East Baltic in the Billingenian (lower Arenig) as part of the earliest known benthic assemblages dominated by elements of the Palaeozoic Evolutionary Fauna. These faunal assemblages usually include bryozoans, ostracodes, and the earliest known porambonitoids, strophomenides and endopunctate orthides, such as Idiostrophia and Orthidium , which later became characteristic of the Whiterockian brachiopod assemblages in Laurentia, but by that time had disappeared from Baltica. The superfamily Syntrophioidea reappears in Baltoscandia in the mid Caradoc. In contrast, Porambonitoidea remained the integral part of the Baltoscandian brachiopod associations through the Ordovician. Porambonites , herein redefined on the basis of restudy of the type species P. intermedius , includes only smooth porambonitoids; taxa with the distinctive ornament of radiating rows of pits first appeared in the group in the mid Arenig. The taxa Eoporambonites gen. nov., Tetralobula peregrina sp. nov., Idiostrophia prima sp. nov. and Idiostrophia tenuicostata sp. nov. are erected.     

Eocene siliceous sponges from the Ebro Basin (Catalonia, Spain)

The Eocene (Bartonian) marls of the La Guixa Member and Gurb Member, Vic Marls Formation (Ebro Basin, Catalonia, Spain), contain a very rich and diversified siliceous sponge fauna. The fauna is dominated by hexactinellids; lithistids and other demosponges are rare. It consists of 16 species representing 16 genera. Eleven new species and two new genera are proposed for these sponges: Reguantella cavernosa nov. gen. nov. sp., Regadrella concinna nov. sp. (both Hexactinellida, Lyssacinosa), Eurete clava nov. sp., Pleuroguettardia iberica nov. sp., Aphrocallistes almeriae nov. sp., Hexactinella informis nov. sp. (all Hexactinellida, Hexactinosa), Brachiolites munterensis nov. sp., Centrosia viquensis nov. sp., Callicylix eocenicus nov. sp., Rhizocheton robustus nov. sp. (all Hexactinellida, Lychniscosa), Propetrosia pristina nov. gen. nov. sp. (Demospongia, Haplosclerida). Some genera of sponges in this fauna are still extant, but, in general, the predominant ones are very close in morphology, and, without doubt, closely related to the Late Cretaceous sponges. This fauna also differs considerably, in terms of composition, from most other described faunas of Tertiary sponges from the Mediterranean region, which are dominated by lithistid sponges. Lithistid sponges are rare in this investigated assemblage, which seems most similar to an as yet undescribed Eocene fauna from Italy. There is ecological differentiation in the proportions of particular sponges in various outcrops and/or stratigraphical levels that is clearly associated with water-depth-related controlling factor(s): Munter, Tona and Sta. Cecilia represent the deepest facies, Gurb is intermediate, and St. Roc and Vespella are the most shallow. The exact bathymetric position of the sponge fauna is difficult to estimate, but it seems that 100 m (but probably 200 m and more in the case of the deepest parts) of water depth may be inferred for this facies.     

海南岛东方早二叠世双壳类动物群及其古生物地理学研究──兼评南龙杂砾岩的冰川成因说

在海南岛东方县江边地区下二叠统南龙组中发现双壳类９属１０种，其中２新种。除新种外，这些双壳类常见于华南和日本的茅口期晚期地层，其它动、植物化石的研究也得出了相同结论，本区无疑是华夏生物区系的组成部分。海南岛的琼中地体不大可能在石炭一二叠纪仍位于冈瓦纳大陆北缘或其附近，南龙杂砾岩应属裂谷成因，与冰川无关。     

Brachiopods and other fossils from the Permo-Triassic boundary beds of the Antalya Nappes (SW Taurus, Turkey)

An uppermost Permian-Lower Triassic biota of brachiopods, conodonts, algae and foraminifers from the Pamucak and Kokarkuyu formations at Çürük Da? (Antalya, Turkey) is here described. The brachiopods belong to two different assemblages: a lower assemblage, early Wuchiapingian in age, with Spinomarginifera cf. S. helica, Spinomarginifera cf. S. iranica, Alatorthotetina sp. ind., Orthothetina sp. ind., Ombonia antalyensis nov. sp. and few specimens of Pennospiriferinoidea; an upper assemblage, Changhsingian in age, comprising S. cf. S. iranica, Spinomarginifera cf. S. spinosocostata, Spinomarginifera sp. ind. and Orthothetina sp. ind., characteristic taxa of the low diversity survival brachiopod faunas of latest Permian age (Survival Fauna 1). The occurrence of the conodont Hindeodus cf. praeparvus above the brachiopod fauna confirms its Changhsingian age. The oolitic grainstones at the top of the Pamucak Formation contain Permocalculus sp., Macroporella cf. apachena, species of Hemigordius and Palaeozoic Lagenida. Coarse calcite fibrous cements pervade the oo-bioclastic grainstones, suggesting early marine cementation. The base of the Kokarkuyu Formation is characterized by the disaster forms Earlandia amplimuralis and “Cornuspira” mahajeri, gastropods and ostracods. The conodont Isarcicella lobata has been recovered 31 m above the base of the Kokarkuyu Formation, indicating the occurrence of the second Triassic conodont zone above the parvus biozone and below the staeschei biozone. The faunal content at the transition of the Pamucak and Kokarkuyu formations records the biotic survival in the aftermath of the end-Permian extinction. Facies evolution from lower energy inner platform wackestones and packstones to higher energy open platform oolitic grainstones indicates a transgression at the top of the Pamucak Formation, which continues into the Lower Triassic Kokarkuyu Formation.