The oldest known occurrence of the Foliomena fauna in the uppermost Darriwilian (Middle Ordovician) of South China

The oldest Foliomena fauna was, until now, known from the middle–upper Miaopo Formation (Nemagraptus gracilis Biozone, lower Sandbian, basal Upper Ordovician) of South China. In this study, the oldest record of the fauna is set back to the latest Darriwilian (upper Hustedograptus teretiusculus Biozone), represented by Foliomena jielingensis and some typical constituents of the Foliomena fauna from the basal Miaopo Formation at Jieling, northern Yichang, western Hubei Province, central China. The Miaopo Formation is characterized by its organic‐rich dark‐grey shale facies, unique in its localized distribution on the Yangtze Platform, and distinguished by its rich and diverse benthic and graptolitic faunas. This suggests an origin of the Foliomena fauna in periodically oxygen‐starved local depressions on the Yangtze Platform during the Middle–Late Ordovician transition.     

TESTATE AMOEBAE FROM THE EARLY JURASSIC OF THE WESTERN TETHYS,NORTH‐EAST ITALY

Abstract: Fossil testate amoebae and their non‐marine finds are rare so their ecological importance through Earth history is poorly understood. The Lower Jurassic shallow water black‐shales of Trento Platform (north‐east Italy) are rich in micro‐organisms and contain a thecamoebian and ostracod assemblage representing the first known record of Early Jurassic oligohaline forms from the European mainland. The thecamoebians are represented by the genera Difflugia, Pontigulasia and Centropyxis. The present discovery of Lower Jurassic thecamoebians in fine carbonate organic‐rich deposits indicates, for the first time, that these sediments can preserve testate amoebae very well. The occurrence of difflugid testate amoebians confirm a transitional marine‐terrestrial habitat, outside large bodies of water, and suggests occasional eutrophication in ephemeral restricted aquatic environment in the Sinemurian–Pliensbachian Trento Platform.     

Reef reconstruction after extinction events of the latest ordovician in the Yangtze platform,South China

Summary Early Silurian reef reconstruction on the Yangtze Platform, in the northern part of the South China Block, is preceded by a combination of regional and global processes. During most of Ashgill time (Late Ordovician), the area was dominated by Wufeng Formation deep water graptolitic black shales. Reefs largely disappeard in the middle of the Ashgill Stage, from the northwestern margin of Cathaysian Land (southeastern South China Block), in advance of the Late Ordovician glaciation and mass extinction, due to regional sea-level changes and regional uplift, unrelated to the mass extinction itselt. Late Ordovician microbial mudmound occurrence is also found in the western margin of the Yangtze Platform, its age corresponding to theDicellograptus complexus graptolite biozone of pre-extinction time. On the Yangtze Platform, a thin, non-reef-bearing carbonate, the Kuanyinchiao Formation (=Nancheng Formation in some sites), thickness generally no more than 1m, occurs near several landmasses as a result of Hirnantian regression. Reappearance of the earliest Silurian carbonates consisting of rare skeletal lenses in the upper part of Lungmachi Formation, are correlated to theacensus graptolite biozone, early Rhuddanian of Shiqian, northeastern Guizhou, near Qianzhong Land. Carbonate sediments gradually developed into beds rich in brachiopods and crinoids in the lower part of Xiangshuyuan Formation, middle Rhuddanian. In the middle part of Xiangshuyan Formation, biostromes, containing abundant and high diversity benthic faunas such as corals, crinoids and brachiopods, show beginnings of reconstruction of reef facies. Substantial reef recovery occurred in the upper part of Xiangshuyuan Formation, lower Aeronian, as small patch reefs and biostromes. During the late Aeronian, carbonate sediments, especially reefs and reef-related facies, expanded on the upper Yangtze Platform, and radiation of reefs occurred in Ningqiang Formation, upper Telychian. The long period of reef recovery, taking several million years, remains difficult to explain, because redistribution of any refugia faunas would be expected to take place soon after the extinction. Reefs and reef-related facies subsequently declined after Telychian time due to regional uplift of the major portion of the Yangtze Platform. Carbonate facies are therefore uncommon in South China during the rest of Silurian time.     

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.     

Scontrone (central Italy), signs of a 9‐million‐year‐old tragedy

The fossilierous bonebeds of Scontrone (Abruzzo region, central Italy) are preserved in tidal‐flat aeolian calcarenites at the base of the Lithothamnion Limestone, a Miocene carbonate ramp widespread in the central‐southern Apennines. The site bears evidence of a catastrophic event at 9 Ma. Reported are the results of the palaeobiological and taphonomic analysis conducted on the rich vertebrate assemblage, particularly on the remains of Hoplitomeryx (Mammalia, Artiodactyla, Ruminantia), recovered from the so‐called Scontrone calcarenites between 1992 and 2012. This is the first taphonomic study of a Late Miocene continental bone assemblage preserved in coastal deposits. The bones are not in primary context. They were likely exhumed during the initial phase of a marine transgression after a period of primary ‘storage’ within a possibly flood‐generated deposit in an estuarine environment. The mortality patterns indicate that the carcasses accumulated in a short time (within a year). The bones of the disarticulated skeletons were then removed, broken in a dry and brittle state, scattered over wide carbonate ramps along an arid to semi‐arid, wind‐exposed coastline and eventually buried again in aeolian calcarenites that drape transgressive tidal‐flat creek deposits. The analysis also reveals that hoplitomerycids were possibly seasonal reproducers and that the land they inhabited, the so‐called Apulia Platform, was probably swept by sudden, disastrous, storm‐supplied flash floods.     

Billingen (Lower Arenig/Lower Ordovician) acritarchs from the East European Platform and their palaeobiogeographic significance

Billingen (Lower Arenig/Lower Ordovician) sediments of the St. Petersburg region, northwest Russia and the Leba area, northern Poland of the East European Craton yield acritarch assemblages, which are largely homogenous though displaying minor compositional differences that probably reflect a gradient from inner to outer shelf environments. Comparison with coeval acritarch microflora from the Yangtze Platform, South China, shows an overall similarity between Baltoscandian and South Chinese phytoplankton. The widespread uniformity in the fossil microphytoplankton may be related to the extensive global 'evae' sea-level transgression, which characterized the Billingen time. This suggests that during the Tremadoc through early Arenig times, acritarch assemblages displayed essentially an undifferentiated cold-water and oceanic character along the whole margin of Perigondwana in the South, as well as on the South Chinese and Baltic platforms, at middle latitudes (Mediterranean oceanic Realm). Despite this overall similarity, however, some typical taxa of the high-latitude Mediterranean Province (Arbusculidium, Coryphidium and Striatotheca) occur in South China, but are absent in Baltica. This discrepancy is explained as caused by differences in climatic and physiographic conditions that prevailed at the two palaeocontinents at this time. The inferred pattern of oceanic circulation during the Lower Ordovician is consistent with the palynological evidence of a prevailing warmer climate in Baltica than in South China, although the two palaeocontinents occupied the same palaeolatitudinal position.     

安徽石台下、中奥陶统紫台组的牙形刺

下、中奥陶统紫台组以紫红色泥质灰岩、瘤状泥质灰岩为特征,具有稳定的空间分布范围,沿扬子台地东南缘呈条带状分布,与扬子台地上发育的湄潭组、大湾组等大致同期。作者研究了安徽石台栗阳柳树亭剖面紫台组的牙形刺,共描述19属23种,识别出四个牙形刺带,从下至上分别是Oepikodus evae带、Baltoniodus triangularis带、Baltoniodus navis带和Paroistodus originalis带,并可与同期笔石带对比。除扬子区外,紫台组还可与欧洲、阿根廷前科迪勒拉等地区的同期地层对比。     

Early Ordovician reefs in South China (Chenjiahe section, Hubei Province): deciphering the early evolution of skeletal-dominated reefs

The Lower Ordovician (late Tremadocian–early Floian) Fenhsiang and the overlying Hunghuayuan Formations at the Chenjiahe section in the Three Gorges area of Hubei Province, South China, include four types of reef: microbe-dominated (lithistid sponge–stromatolite and lithistid sponge–calcimicrobial) reefs, and skeletal-dominated (lithistid sponge–bryozoan and bryozoan–pelmatozoan) reefs. The microbe-dominated reefs are characterized by the dominance of microbial sediments that encrusted and bound the surfaces of sponges to reinforce the reef frameworks. In contrast, the skeletal-dominated reefs are distinguished by bryozoans that encrusted frame-building sponges and pelmatozoans, and that grew downward to fill the open spaces available within the frameworks. A series of these reefs shows a temporal succession in reef type, with a decline in the lithistid sponge–stromatolite reefs and an increase in the lithistid sponges and receptaculitids within the lithistid sponge–calcimicrobial reefs in the Hunghuayuan Formation; the lithistid sponge–bryozoan reefs are common in both the Fenhsiang and Hunghuayuan Formations. These features of the Chenjiahe reefs are in marked contrast to other coeval reefs on the Yangtze Platform and elsewhere. Skeletal-dominated reefs first developed in the Three Gorges and adjacent areas, located on the central part of the platform. Likewise, lithistid sponges and receptaculitids first developed in the Three Gorges area and then expanded their range. In contrast, stromatolites declined over time, but remained abundant on a marginal part of the platform. The spatial–temporal distributions of these reefs on the Yangtze Platform reflect the initiation of the Great Ordovician Biodiversification Event and its consequences, although influenced by local environmental conditions. The Three Gorges area was a center for the development of skeletal-dominated reefs, which were established earlier here than elsewhere in the world. These reef types and their spatial–temporal successions provide invaluable clues to the earliest evolution of skeletal-dominated reefs and their ensuing development during the Middle–Late Ordovician.     

Uncovering the spatial heterogeneity of Ediacaran carbon cycling

Records of the Ediacaran carbon cycle (635–541 million years ago) include the Shuram excursion (SE), the largest negative carbonate carbon isotope excursion in Earth history (down to ?12‰). The nature of this excursion remains enigmatic given the difficulties of interpreting a perceived extreme global decrease in the δ¹³C of seawater dissolved inorganic carbon. Here, we present carbonate and organic carbon isotope (δ¹³C_carb and δ¹³C_org) records from the Ediacaran Doushantuo Formation along a proximal‐to‐distal transect across the Yangtze Platform of South China as a test of the spatial variation of the SE. Contrary to expectations, our results show that the magnitude and morphology of this excursion and its relationship with coexisting δ¹³C_org are highly heterogeneous across the platform. Integrated geochemical, mineralogical, petrographic, and stratigraphic evidence indicates that the SE is a primary marine signature. Data compilations demonstrate that the SE was also accompanied globally by parallel negative shifts of δ³⁴S of carbonate‐associated sulfate (CAS) and increased ⁸⁷Sr/⁸⁶Sr ratio and coastal CAS concentration, suggesting elevated continental weathering and coastal marine sulfate concentration during the SE. In light of these observations, we propose a heterogeneous oxidation model to explain the high spatial heterogeneity of the SE and coexisting δ¹³C_org records of the Doushantuo, with likely relevance to the SE in other regions. In this model, we infer continued marine redox stratification through the SE but with increased availability of oxidants (e.g., O₂ and sulfate) limited to marginal near‐surface marine environments. Oxidation of limited spatiotemporal extent provides a mechanism to drive heterogeneous oxidation of subsurface reduced carbon mostly in shelf areas. Regardless of the mechanism driving the SE, future models must consider the evidence for spatial heterogeneity in δ¹³C presented in this study.     

Formation of large carbonate concretions in black cherts in the Gufeng Formation (Guadalupian) at Enshi,South China

The formation of carbonate concretions is a cementation process which passively infills the pore spaces within sediments. They record the original environments of deposition and diagenetic conditions of the host rocks. Little is known about the precise mechanisms responsible for the precipitation of carbonate concretions. The most common host rocks are mudstones/shales, sandstones, and limestones. This study presents an example of large carbonate concretions from an unusual host rock, the black bedded cherts of the Gufeng Formation (Guadalupian) at Enshi on the northern Yangtze Platform, South China. Petrographic observations (X‐ray diffraction, optical microscopy, scanning electron microscopy) and multiple geochemical analyses (pyrite‐ and carbonate‐associated‐sulfate (CAS)‐sulfur isotopes, carbon isotopes) indicate that (a) the studied carbonate concretion are mainly composed of micritic calcite with subordinate dolomite; (b) the concretions may have been mainly formed in the bacterial sulfate reduction (BSR) zone during very early diagenesis near the sediment–water surface; (c) the paleo‐bottom water overlying the sediments during formation of the concretions was mainly euxinic; and (d) the growth of the studied concretions proceeded via a pervasive model, where later cementation phase initiated in the lower part of the concretions and progressed upward.     

Palaeoenvironmental and biostratigraphical implications of selected Floian and Dapingian (Ordovician) chitinozoans of the South China Palaeoplate

Chitinozoans are widespread microfossils in the Ordovician to Devonian strata. Although they have been widely adopted in biostratigraphy, their environmental preferences are rarely discussed. In this study, the palaeoecological distribution of four Floian and Dapingian key chitinozoans in six coeval stratigraphical units based on 13 sections from the South China Palaeoplate is discussed in detail, including Bursachitina maotaiensis (Chen 2009a), Bursachitina qianbeiensis (Chen 2009a), Conochitina decipiens and Sagenachitina dapingensis (Chen 2009b). It appears that B. maotaiensis and B. qianbeiensis preferred inner shelf environments and could spread to near‐shore and shallow outer shelf settings. C. decipiens mostly favoured inner shelf and shallow outer shelf environments. S. dapingensis had the widest environmental tolerance and was adapted to almost all environments, with the exception of the near‐shore area on the Yangtze Platform. Biostratigraphically, the four species have relatively well‐constrained ranges, and their first appearances provide good bases for regional correlations. The endemic B. maotaiensis and B. qianbeiensis can be good markers for the upper Floian, but their relatively narrow environmental preferences should be taken into account. S. dapingensis proves to be a good marker for the Dapingian in the South China Palaeoplate, except in the near‐shore areas. The globally distributed C. decipiens also has a biostratigraphical significance in most areas of the Yangtze Platform. Our study indicates that well‐documented environmental preferences of key species help to provide more reliable and practical biostratigraphical correlations.     

湖北峡东地区九龙湾剖面震旦系陡山沱组微体化石的新发现

中国南方扬子地台震旦系陡山沱组产出丰富的微体化石,它们主要保存在磷块岩以及燧石结核和条带中。文章详细报道湖北峡东地区九龙湾剖面震旦系陡山沱组微体化石,描述以前未曾在峡东地区碳酸盐相燧石中发现的8属8种微体化石。研究九龙湾剖面陡山沱组大型带刺疑源类、微体多细胞藻类和动物胚胎化石的分布特征,发现Tianzhushania spinosa是最早出现的大型带刺疑源类分子,大冰期后微体生物的辐射是一个阶段性渐进的过程。同时．本项研究进一步证实华南扬子区陡山沱组碳酸盐相燧石和磷块岩地层中保存的微体化石面貌基本一致。     

THE LATE TRIASSIC BLACK SHALES OF THE GUANLING AREA, GUIZHOU PROVINCE, SOUTH-WEST CHINA: A UNIQUE MARINE REPTILE AND PELAGIC CRINOID FOSSIL LAGERSTÄTTE

Abstract:  Black shales of the lower member of the Carnian Xiaowa Formation (previously known as the Wayao Member of the Falang Formation or as the Wayao Formation) in the Guanling area, Guizhou Province, south-west China, are yielding a rich marine reptile fauna and exceptional remains of pelagic crinoids. The black shales represent deposition on the drowned southern margin of the Yangtze Platform during a Maximum Flooding Interval. The relatively reduced sedimentation rates led to the formation of the Lagerstätte through the accumulation of fossils in the anoxic bottom sediments over a prolonged period of time. Invertebrate fossils represent almost exclusively pelagic forms, such as a diverse ammonite fauna and halobiid bivalves. The spectacular finds of colonies of large (stem lengths > 11 m) crinoids of the genus Traumatocrinus attached to driftwood prove that this crinoid was the first to evolve a pseudoplanktonic life style. The other crinoid is the planktonic roveacrinid Osteocrinus . The marine reptile fauna, represented by probably hundreds of skeletons, is numerically dominated by three species of ichthyosaurs and four species of thalattosaurs. The thalattosaurs fill a palaeobiogeographic gap between the Alpine thalattosaur faunas and those from western North America. Two species of placodonts are rare finds. As for the thalattosaurs, the placodont occurrences greatly expand the geographic range of the group because placodonts have been known previously only from the Mediterranean region, the Alps and the Muschelkalk Basin. The unique abundance of thalattosaurs contrasts with a scarcity of fishes. Although we suggest that the fauna is authochthonous and inhabited surface waters, it must have represented an unusual ecosystem. However, the possibility remains that both the marine reptiles and the Traumatocrinus colonies were concentrated in the region by currents and do not reflect the biocoenosis.     

Resolving Terreneuvian stratigraphy in subtidal–intertidal carbonates: palaeontological and chemostratigraphical evidence from the Turukhansk Uplift,Siberian Platform

Both diverse assemblages of small skeletal fossils and a representative chemostratigraphical record make the Siberian Platform widely regarded as one of the key regions for the reconstruction of global biotic and abiotic events in the late Ediacaran and early Cambrian. However, the wide distribution of intertidal–subtidal facies in the Ediacaran–Cambrian transitional strata of the central and southwestern Siberian Platform (Turukhansk–Irkutsk–Olekma facies region) produces a dramatic depletion of the palaeontological record and considerably limits their age‐calibration and long‐distance correlation. We report new lithological, palaeontological and carbonate carbon‐isotope data for the Ediacaran–Cambrian sections of the Turukhansk Uplift (northwestern Siberian Platform, western facies region). These data provide a robust framework for the chemostratigraphical correlation of the western facies region with sections of the transitional and eastern regions of the Siberian Platform and further confirms a depositional hiatus at the base of the Tommotian Stage in the stratotype section (Aldan River, SE Siberia). The carbon‐isotope curve from the Turukhansk Uplift sections correlates positively with the most chemostratigraphically representative Ediacaran–Cambrian sections (Siberia, Morocco, South China). It records major carbon‐isotope oscillations globally recognized in the lower Cambrian, enabling localization of the Fortunian and Cambrian Stage 2 boundaries in the Platonovskaya Formation. Although there is extreme paucity and poor preservation of the small skeletal fossils in the western facies region, we report individual Barskovia, Blastulospongia and chancelloriid sclerites from the Platonovskaya Formation. A combination of palaeontological and chemostratigraphical data suggests the base of P. antiqua Assemblage Zone is located in the middle Platonovskaya Formation. The earliest spiral gastropods probably occurred at ~541 Ma, as demonstrated by the discovery of a specimen of Barskovia near the base of the large negative excursion in the lower Platonovskaya Formation, correlated with the BACE negative carbon‐isotope peak in the sections of the Yangtze Platform.     

Effects of developmental conditions on growth,stress and telomeres in black‐legged kittiwake chicks

Early‐life conditions can drive ageing patterns and life history strategies throughout the lifespan. Certain social, genetic and nutritional developmental conditions are more likely to produce high‐quality offspring: those with good likelihood of recruitment and productivity. Here, we call such conditions “favoured states” and explore their relationship with physiological variables during development in a long‐lived seabird, the black‐legged kittiwake (Rissa tridactyla). Two favoured states were experimentally generated by manipulation of food availability and brood size, while hatching order and sex were also explored as naturally generating favoured states. Thus, the favoured states we explored were high food availability, lower levels of sibling competition, hatching first and male sex. We tested the effects of favoured developmental conditions on growth, stress, telomere length (a molecular marker associated with lifespan) and nestling survival. Generation of favoured states through manipulation of both the nutritional and social environments furthered our understanding of their relative contributions to development and phenotype: increased food availability led to larger body size, reduced stress and higher antioxidant status, while lower sibling competition (social environment) led to lower telomere loss and longer telomere lengths in fledglings. Telomere length predicted nestling survival, and wing growth was also positively correlated with telomere length, supporting the idea that telomeres may indicate individual quality, mediated by favoured states.     

ADP‐glucose pyrophosphorylase genes,associated with kernel weight,underwent selection during wheat domestication and breeding

ADP‐glucose pyrophosphorylase, comprising two small subunits and two large subunits, is considered a key enzyme in the endosperm starch synthesis pathway in wheat (Triticum aestivum L.). Two genes, TaAGP‐S1‐7A and TaAGP‐L‐1B, were investigated in this study. Haplotypes of these genes were associated with thousand kernel weight (TKW) in different populations. Mean TKWs of favoured haplotypes were significantly higher than those of nonfavoured ones. Two molecular markers developed to distinguish these haplotypes could be used in molecular breeding. Frequencies of favoured haplotypes were dramatically increased in cultivars released in China after the 1940s. These favoured haplotypes were also positively selected in six major wheat production regions globally. Selection of AGP‐S1 and AGP‐L‐1B in wheat mainly occurred during and after hexaploidization. Strong additive effects of the favoured haplotypes of with other genes for starch synthesis were also detected in different populations.     

MARINE REPTILES FROM THE LOWER CRETACEOUS OF SOUTH AUSTRALIA: ELEMENTS OF A HIGH-LATITUDE COLD-WATER ASSEMBLAGE

Abstract: The Lower Cretaceous rocks of South Australia have yielded a diverse marine reptile assemblage of up to five families of plesiosaur (including a new cryptoclidid or cimoliasaurid, indeterminate elasmosaurids, a possible polycotylid, rhomaleosaurids, and pliosaurid) and one family of ichthyosaur (ophthalmosaurid). Other common associated vertebrates include chimaerids and osteichthyans. Sharks, dipnoans and dinosaurs are uncommon and marine turtles are notably absent. The main fossil‐producing strata belong to the Lower Aptian–Lower Albian Bulldog Shale although the Upper Albian Oodnadatta Formation has produced isolated elements. Both these units comprise finely laminated shaly mudstones and claystones deposited in a transgressive shallow coastal, epicontinental marine environment. Estimates of palaeolatitude place South Australia between 60° and 70°S, in the late Early Cretaceous. Sedimentary structures (including lonestone boulders and glendonites), fossils, isotope data and climatic modelling also indicate that seasonally cool–cold conditions (possibly with winter freezing) prevailed during deposition of the Bulldog Shale. This contrasts markedly with climate regimes typically tolerated by modern aquatic reptiles but suggests that some of the South Australian Mesozoic taxa may have possessed adaptations (including elevated metabolic levels and/or annual migration) to cope with low temperatures. A high proportion of juvenile plesiosaur remains in the Bulldog Shale might also indicate that nutrient‐rich cold‐water coastal habitats functioned as both ‘safe calving grounds’ and refuges for young animals prior to their entering the open sea as adults. The occurrence of plesiosaurs and ichthyosaurs in the high‐latitude Lower Cretaceous of southern Australia, along with plesiosaurs and mosasaurs in the Upper Cretaceous of South America, Antarctica, New Zealand and the Chatham Islands, demonstrates that Mesozoic marine reptiles utilized southern high‐latitude environments over a considerable period of time, and that these records do not represent casual occupation by isolated taxa.     

Influence of the Late Ordovician glaciation on basin configuration of the Yangtze Platform in China

The Late Ordovician paleogeographic changes in the Yangtze Platform indicate a widespread regression and consequent subaerial exposure probably caused by the 'locking up' of substantial amounts of marine waters during the Late Ordovician glaciation. The subsequent rapid paleogeographic changes on the Yangtze Platform during the earliest Silurian suggest a rapid melting of the ice. The relatively cool waters in the partially closed Yangtze basin during the latest Ordovician were replaced by open and warm waters during the earliest Silurian. Sedimentation rates and composition of faunal assemblages underwent marked changes during latest Ordovician and Early Silurian. Glaciation, Ordovician, Silurian, Paleogeography, sedimentary rate, faunal change.     

Climate‐driven rampant speciation of the Cape flora

Aim To test whether the radiation of the extremely rich Cape flora is correlated with marine‐driven climate change. Location Middle to Late Miocene in the south‐east Atlantic and the Benguela Upwelling System (BUS) off the west coast of South Africa. Methods We studied the palynology of the thoroughly dated Middle to Late Miocene sediments of Ocean Drilling Program (ODP) Site 1085 retrieved from the Atlantic off the mouth of the Orange River. Both marine upwelling and terrestrial input are recorded at this site, which allows a direct correlation between changes in the terrestrial flora and the marine BUS in the south‐east Atlantic. Results Pollen types from plants of tropical affinity disappeared, and those from the Cape flora gradually increased, between 10 and 6 Ma. Our data corroborate the inferred dating of the diversification in Aizoaceae c. 8 Ma. Main conclusions Inferred vegetation changes for the Late Miocene south‐western African coast are the disappearance of Podocarpus‐dominated Afromontane forests, and a change in the vegetation of the coastal plain from tropical grassland and thicket to semi‐arid succulent vegetation. These changes are indicative of an increased summer drought, and are in step with the development of the southern BUS. They pre‐date the Pliocene uplift of the East African escarpment, suggesting that this did not play a role in stimulating vegetation change. Some Fynbos elements were present throughout the recorded period (from 11 Ma), suggesting that at least some elements of this vegetation were already in place during the onset of the BUS. This is consistent with a marine‐driven climate change in south‐western Africa triggering substantial radiation in the terrestrial flora, especially in the Aizoaceae.     

Morphology,Morphogenesis, and Molecular Phylogeny of Anteholosticha multicirrata n. sp. (Ciliophora,Spirotrichea) with a Note on Morphogenesis of A. pulchra (Kahl, 1932) Berger, 2003

Two marine urostylid ciliates, Anteholosticha multicirrata n. sp. and Anteholosticha pulchra (Kahl, 1932) Berger, 2003, were collected from South Korea. These species were identified based on morphology, morphogenesis, and SSU rRNA gene sequence comparison. Anteholosticha multicirrata n. sp. is characterized by the following features: body size 90–125 × 30–45 μm in vivo, shape slender to ellipsoidal in outline, with yellow‐greenish cortical granules distributed along and between dorsal kineties and cirri; single contractile vacuole positioned on left at mid‐body; three frontal, five to seven frontoterminal, one buccal, one to two pretransverse and four to six transverse cirri; three complete dorsal kineties; one left and one right marginal cirral row; about 117 macronuclear nodules; and three to four micronuclei observed during morphogenesis. In addition, based on the observations of morphogenesis, we found that A. pulchra has pretransverse cirri, which were not described in detail in previous studies. Nuclear small subunit ribosomal RNA (SSU rRNA) gene was used to analyse their phylogenetic relationship, and the gene tree supports that the genus Anteholosticha is a highly polyphyletic group.