Latest Guadalupian brachiopods from the Guadalupian/Lopingian boundary GSSP section at Penglaitan in Laibin, Guangxi, South China and implications for the timing of the pre-Lopingian crisis

A brachiopod fauna comprising nine species in eight genera from three closely spaced stratigraphic horizons of the same stratigraphic section is described for the first time from the Laibin Limestone in the uppermost part of the Maokou Formation in the Guadalupian/Lopingian (G/L) GSSP section at Penglaitan, Guangxi Autonomous Region, South China. The brachiopod assemblages are bracketed between two conodont zones: Jinogondolella xuanhanensis Zone below and Jinogondolella granti Zone above and, therefore, they can be safely assigned to the latest Capitanian in age. However, all but one of the nine brachiopod species from the Laibin Limestone carry strong early Lopingian (Wuchiapingian) aspect. Thus, the discovery of this brachiopod fauna not only suggests that some Lopingian brachiopod species had already appeared in the late Guadalupian (Capitanian); more importantly, it has also highlighted the fact that both the previously noted pre-Lopingian life crisis (or end-Guadalupian or Middle Permian mass extinction) and Lopingian recovery/radiation actually occurred in late Capitanian times, sometime before the G/L chronostratigraphic boundary. So far, the Penglaitan GSSP section provides the highest-resolution disappearance patterns of different fossil groups around the G/L boundary.     

New latest Permian foraminifers from Laren (Guangxi Province, South China): Palaeobiogeographic implications

Microfacies analyses performed on the latest Permian Wujiaping Formation at Laren (Guangxi Province, South China) show that the bioclastic-rich limestones of Late Permian age contain a rich and well-diversified foraminiferal fauna. This fauna is here revised in order to be compared with time-equivalent levels of southern Iran and southern Turkey. Some new and unexpected phylogenetic trends are highlighted among the biseriamminoids. The new or poorly known genera Retroseptellina, Septoglobivalvulina, Paraglobivalvulinoides, Dagmarita?, Bidagmarita nov. gen., Louisettita, Paradagmaritopsis nov. gen. and Paradagmarita? are concerned. Nevertheless, these newly appeared biseriamminoids are subordinate to abundant Tetrataxis and Climacammina, ultimate survivors of the families Palaeotextulariidae and Tetrataxidae, appeared as old as the Early Carboniferous (“Mississippian”). Algae, miliolids, and nodosarioids are poorly represented. Two genera and four species are here newly described: Globivalvulina curiosa nov. sp., Louisettita ultima nov. sp., Bidagmarita nov. gen., Bidagmarita sinica nov. gen. nov. sp., Paradagmaritopsis nov. gen., Paradagmaritopsis kobayashii nov. gen. nov. sp. The palaeogeographic distribution of these foraminifers is interpreted to be typically of Neo-Tethyan regions, ranging from southern Turkey (Hazro) to South China (Laren) and up to Japan for some species (i.e., Paradagmaritopsis). At Laren, Late Permian strata are generally characterized by Reichelina ex gr. simplex Sheng. Isolated samples of packstones, collected in Tsoteng region (Guangxi Province, South China), contain Sphaerulina sp. together with various smaller foraminifers and numerous representatives of the new species G. curiosa nov. sp. In this study we demonstrate that the regions of Zagros (Iran), Taurus (Turkey), South China and even Japan shared similar foraminiferal assemblages and represented intermittently connected palaeobiogeographic provinces during Late Permian times.     

Lower Middle Devonian,Eifelian, crinoids from central Guangxi,South China

The extensive Devonian marine deposits of South China have yielded few articulated crinoid cups or theca. Two Eifelian specimens, from the Gupa Member, are the first ones reported from the Yingtang Formation, Eifelian, from the Ma’anshan section, Guangxi, South China. The new taxon Guangxicrinus xiangzhouensis n. gen. n. sp. is the first report of a marsupiocrinid in China, extending the paleogeographic range of the family into the Paleotethys and the stratigraphic range of the family upward from the upper Silurian into the lower Middle Devonian, Eifelian. The occurrence of Halocrinites sp. is the third occurrence of a cupressocrinitid in China and extends the paleogeographic range from Yunnan to Guangxi.     

Discovery of Anticostia uniformis from the Xiazhen Formation at Zhuzhai,South China and its stratigraphic implication

The Xiazhen Formation is an Upper Ordovician lithostratigraphic unit in the Jiangshan-Changshan-Yushan (JCY) area, which contains series of Late Ordovician reef successions. The reef successions of the Xiazhen Formation at Zhuzhai are critical for evaluation of the Late Ordovician marine diversity and palaeoecology. However, their age has long been uncertain and generally is regarded as of upper Katian, based on the occurrences of shelly fossils and correlation with the stratigraphic equivalent Changwu Formation. The newly discovered graptolite species Anticostia uniformis, in the Xiazhen Formation, together with the combined evidence of brachiopods and sedimentology, indicates an age range for the graptolite locality from the Dicellograptus complanatus Biozone to the Diceratograptus mirus Subzone of late Katian, but the graptolites do not rule out the possibility that it is Hirnantian.     

Integrated radiolarian and conodont biostratigraphy of the Middle Permian Gufeng Formation (South China)

Radiolarians are usually abundant in chert sequences and they have thus been widely used for the biostratigraphy of deep-water sediments. However, there are many difficulties in the correlation of radiolarian biostratigraphic schemes with the standard conodont zones. In this study, 21 radiolarian species were extracted from the Gufeng Formation that crops out in the Luojiaba (LJB) section (western Hubei, China), together with 5 co-occurring conodont species. In this way, it is the first time that the Pseudoalbaillella globosa, Follicucullus monacanthus and F. scholasticus radiolarian zones can be directly correlated with the Jinogondolella nankingensis gracilis, J. aserrata and J. postserrata conodont zones. Accordingly, the 3 radiolarians zones are now firmly correlated with the Roadian to middle Capitanian interval (Middle Permian).     

Diverse small spinose acritarchs from the Ediacaran Doushantuo Formation, South China

The Ediacaran Doushantuo Formation in South China is underlain by the Cryogenian Nantuo Formation (glacial rocks) and overlain by the late Ediacaran Dengying Formation. It is characterized by well-preserved, large (normally >100 μm in size) spinose acritarchs (LSAs), which have been shown to be probably the only useful biostratigraphic tool for the global correlation of the early- and middle-Ediacaran. Acritarchs are organic microfossils normally known as single-celled eukaryotic organisms (protists). Although recent research suggests that some large spinose acritarchs may represent diapause egg cysts of metazoans, the biological affinities of the Ediacaran spinose acritarchs, especially for those displaying remarkable size ranges, are still debatable.Recently, smaller specimens of the Ediacaran spinose acritarchs have been found in cherts and phosphorites of the Doushantuo Formation in South China. Many described Ediacaran spinose acritarch taxa display large size variation (from tens to hundreds of microns in vesicle diameter), but some taxa only have smaller (<70 μm) specimens. The morphological comparison with Paleozoic counterparts indicates that some Ediacaran spinose acritarchs may have phylogenetic affinity to eukaryotic algae. More evidence, including wall ultra-structure, geochemical analysis and comparison with modern analogs, is needed to understand the biological affinity of the Ediacaran spinose acritarchs. The remarkable radiation of planktonic protists, characterized by abundant, diverse spinose acritarchs, occurred as early as in the late Neoproterozoic, i.e., 40–60 million years earlier than previously thought.     

Late Bashkirian and early Moscovian conodonts from the Naqing section,Luodian, Guizhou,South China

Late Bashkirian and early Moscovian conodonts are abundant and diverse at the Naqing section, South China. All conodont genera known to have numerous species in the late Bashkirian–early Moscovian are recorded here, including Declinognathodus, Diplognathodus, Gondolella, Idiognathodus, Idiognathoides, Mesogondolella, Neognathodus, and Neolochriea. At Naqing, many species of these genera provide a succession of conodont chronomorphoclines throughout the Bashkirian–Moscovian boundary interval. They demonstrate that deposition was remarkably continuous through the boundary interval, a major criterion for selecting a Global Stratotype Section and Point (GSSP). This paper describes the current state of knowledge for several of these chronomorphoclines, and also provides an updated range chart of conodonts recovered from the Naqing section and their correlation with other regions.The taxon that best matches the current concept for the base of the Moscovian Stage in its type region is the phylogenetic first occurrence of Diplognathodus ellesmerensis. An ancestral form with most of the characteristics of D. ellesmerensis occurs at Naqing. More specimens are needed to completely document the chronomorphocline, but because D. ellesmerensis is found worldwide — including that close to the base of the type Moscovian — its evolutionary first occurrence would provide an almost ideal GSSP to define the base of the international Moscovian Stage.     

Age constraints of the Hungshihyen Formation (Early to Middle Ordovician) on the western margin of the Yangtze Platform,South China: New insights from chitinozoans

The Hungshihyen Formation represents the Lower to Middle Ordovician near-shore siliciclastic deposits on the western margin of the Yangtze Platform, South China. However, its age is still debated, largely because of insufficient studies. Here we documented the Bursachitina maotaiensis–B. qianbeiensis chitinozoan assemblage from the lower part of the Hungshihyen Formation at Songliang, Qiaojia County, eastern Yunnan Province. This assemblage is remarkably similar to an assemblage that roughly correlates to the middle part of the Corymobograptus deflexus graptolite Biozone in northern Guizhou Province, indicating that the Hungshihyen Formation at Songliang is probably of late Floian age and may extend into the early Dapingian. Additionally, a revision on the chitinozoans previously documented from the strata assigned to the same formation in the Wuding area was made according to the latest classification. The revision allows the recognition of the Euconochitina symmetrica–Eremochitina brevis assemblage, and therefore suggests a late Tremadocian age for this interval based on regional and global chitinozoan biostratigraphic correlations. Considering also its lithologic succession, we argue that the chitinozoan-bearing strata in the Wuding area previously assigned to the Hungshihyen Formation correspond most likely to the uppermost part of the underlying Tangchi Formation or the lowermost part of the Hungshihyen Formation. The base of the Hungshihyen Formation appears therefore to be diachronous in eastern Yunnan Province.     

Latest Permian Palaeolithocycliidae (Radiolaria) from South China

The family Palaeolithocycliidae Kozur and Mostler was formerly thought to be ranging from Devonian to Carboniferous. However, a lot of radiolarians assignable to this family were discovered in the late Changhsingian (Latest Permian) of South China. Six species, including Palaeolithocyclia pilata n. sp., Palaeolithocyclia platta n. sp., Paramphibrachium woni n. sp., Klaengspongus spinosus Sashida, Klaengspongus formosus n. sp. and Klaengspongus umbilicatus n. sp., have been identified. In this paper, these species are illustrated and described.     

Changhsingian (Late Permian) foraminifers from the topmost part of the Xiala Formation in the Tsochen area,central Lhasa Block,Tibet and their geological implications

A foraminiferal fauna consisting of 15 genera and 19 species is documented for the first time from the topmost part of the Xiala Formation in the Aduogabu area in Tsochen County, central Lhasa Block. This foraminiferal fauna is dominated by Colaniella, indicating a broadly Changhsingian age. The presence of Colaniella, Reichelina and absence of the typical tropical fusuline genus Palaeofusulina in the fauna indicate that the Lhasa Block has not merged into equatorial regions during the Changhsingian. More importantly, the widespread Lopingian (Late Permian) marine carbonates with warm-water faunas and the stable platform carbonate sequence through the Guadalupian and Lopingian in the Lhasa Block present an obvious contrast against the contemporaneous sequences in the South Qiangtang Block and Gondwana margin. It suggests that both the Bangong-Nujiang Ocean and the Neotethys Ocean would have opened by the Guadalupian and Lopingian.     

New ophiuroids from the Permian/Triassic boundary beds of South China

A new genus of ophiuroid, Huangzhishania , is created based on new material from the Permian/Triassic boundary beds at the Huangzhishan section, South China. The age of the new genus is constrained as earliest Griesbachian by means of faunal correlation of the associated bivalves and stratigraphical correlation with the Mixed Fauna Beds of the neighbouring Meishan section. Taphonomic and palaeoecological evidence suggest that the collapse of the ophiuroid association was related to a catastrophic event, and Huangzhishania was rapidly buried in life position.     

Latest Permian Spumellaria and Entactinaria (Radiolaria) from South China

A diverse and well-preserved latest Permian radiolarian fauna was obtained from bedded siliceous rocks and siliceous mudstones of the Dongpan Section, southwest Guangxi, China. All encountered specimens of the order Spumellaria and a few specimens of the order Entactinaria were selected for the taxonomic study of this paper. Thirty-three species, 15 of which are new species, were identified. They belong to 15 genera, three of which (Paracopicyntra, Copiconulus, and Yujingella) are new. The most interesting result of our study is that eight typical Middle Triassic spumellarian genera (Paroertlispongus Kozur and Mostler, Tetrapaurinella Kozur and Mostler, Paurinella Kozur and Mostler, Lithelius Haeckel, Archaeospongoprunum Pessagno, Tamonella Dumitrica, Kozur and Mostler, Bistarkum Yeh, and Tetraspongodiscus Kozur and Mostler) were discovered in the upper Changhsingian strata studied herein. Therefore, the most important and characteristic spumellarian families of the Middle Triassic were already present in the Late Permian of South China.     

Early Permian bioevent in the fusulinacean fauna of South China

Analysis of a large database of the stratigraphic distribution of fusulinacean Foraminifera reveals an Early Permian event of significant decline of species diversity in South China. Data from Late Carboniferous to Early Permian sections without apparent unconformity in southwest China were evaluated to determine if the apparent pattern of species disappearance was caused by bias in fossil preservation associated with Early Permian sea-level changes. Statistical analysis suggests that the Early Permian event started in the Late Sakmarian with a significant drop of species diversity in the Robustoschwagerina ziyunensis Zone and continued through the Pamirina darvasica Zone of the Artinskian and into the Brevaxina dyhrenfurthi Zone of the Early Kungarian, resulted in a total loss of about 40% species diversity in the fusulinacean fauna. The Early Permian event is the most extensive bioevent in the history of fusulinacean Foraminifera at the species level although it is less significant at the generic level. Because a similar faunal change has been found among the fusulinacean assemblages in North America and in various regions of Tethys, this event may represent a major faunal turn-over in response to the Early Permian changes in sea level and could be of a global nature. Previous recognition of this event was hampered by Early Permian unconformities in North America and other regions of Tethys.     

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.     

Dickinsonia from the Ediacaran Dengying Formation in the Yangtze Gorges area,South China

Dickinsonia is an iconic fossil of the Ediacara biota (~575–539 Ma). It was previously known from siliciclastic successions of the White Sea assemblage in Australia, Baltica, and possibly India. Here we describe Dickinsonia sp. from the terminal Ediacaran Shibantan Member limestone (ca. 551–543 Ma) of the Dengying Formation in the Yangtze Gorges area of South China. The stratigraphic distribution of Ediacara-type fossils in the Shibantan Member indicates that this biota uniquely preserves both the White Sea and Nama assemblages in stratigraphic succession. The new data presented here suggests that Dickinsonia had wider paleogeographic and paleoenvironmental distributions, implying its strong dispersal capability and environmental tolerance.     

Conodont biostratigraphy of the Yujiang Formation (Emsian,Lower Devonian) at Shizhou,Guangxi, South China

We study conodonts from the upper part of the Shizhou Member of the Yujiang Formation in Liujing area for the first time. Relatively abundant conodonts were collected from six sampling levels located between the uppermost part of the Shizhou Member to the lowermost part of the Daliancun Member at the Shizhou section, Liujing, Guangxi. The material includes Polygnathus excavatus excavatus Carls and Gandl, P. excavatus ssp. 114 Carls and Valenzuela-Ríos, P. nothoperbonus Mawson, P. perbonus (Philip) as well as ?Ozarkodina? midundenta (Wang and Ziegler) and ?O.? prolata Mawson. The lowest record of P. nothoperbonus is documented 0.35 m below the boundary between the Shizhou and Daliancun members. Correlation of conodont biostratigraphy between the Shizhou and Liujing sections indicates that the upper part of the Shizhou Member (partially) belongs to the excavatus Zone and the Daliancun Member belongs to the nothoperbonus Zone.     

A new oryctocephalid trilobite from the Balang Formation (Cambrian Stage 4) of northwestern Hunan,South China,with remarks on the classification of oryctocephalids

A new trilobite, Longaspis paiwuensis n. gen. n. sp., from the Balang Formation (Cambrian Stage 4) in northwestern Hunan, South China, is described. This rare trilobite adds to an expanding taxonomic list of organisms recognized from the Balang Lagerstätte, a deposit of exceptional preservation from the Cambrian. Longaspis paiwuensis is an unusually large-sized, micropygous oryctocephalid trilobite that has proparian facial sutures, pit-like lateral glabellar furrows, up to 17 thoracic segments, and a distinct medial notch in the pygidium; it lacks marginal spines.The classification of the family Oryctocephalidae is reviewed. Three subfamilies are recognized, and Longaspis n. gen. is assigned to the subfamily Oryctocarinae.     

A new molar from the Middle Pleistocene hominid assemblage of Yanhuidong,Tongzi, South China

1988年,贵州省博物馆对桐梓岩灰洞的支洞进行了最后一次发掘。2014年,在洞内第四层堆积物中鉴定出逾2000件的动物牙齿化石,以及一枚古人类上颊齿(编号:TZ-1)。1991年,铀系法测定这些次生堆积物的沉积年代约为距今24万年。本文运用高精度CT(巴黎自然历史博物馆)对TZ-1的釉质齿质界面(EDJ)和牙髓腔几何形态进行了分析。TZ-1的冠面形态有如下特征:次尖小且在远中舌侧不发育,咀嚼面轮廓呈四边形,颊舌径稍大过近中远中径,原尖舌侧齿带发育,齿尖从大到小依次为原尖、后尖、前尖和次尖。TZ-1牙髓腔的髓角与其釉质齿质界面以及釉质表面的形态都具有相关性。TZ-1的形态与M1虽有相似之处,但完全不同于1983年出土于同一层位的另两颗M1;其应被鉴定为dm2,并可被归入中中更新世的中国直立人支系。岩灰洞上臼齿PA 875的形态与建始龙骨洞PA 1279和周口店直立人等古老型直立人相似。岩灰洞另一枚刚萌发的臼齿PA 874具有凸出的次尖和长菱形的外廓,接近于爪哇型直立人Sangiran NG 91-G10;这也是智人和尼安德特人的共有衍征。但PA 874的冠面仍保留了亚洲型的齿带,因而被归入人属未定种。因出土自次生堆积,岩灰洞的三种古人类类型未必曾同时并存,但却揭示了华南地区人类演化进程中的多样面貌。     

Microfacies of a Permian calcisponge reef in Lichuan,western Hubei,South China

The Lichuan Jiantianba reef is located at the platform margin between the carbonate platform and the marine trough in western Hubei, China. The water depth of this area became shallow in the late Permian Changhsingian Age, and a huge aggradation-progradation platform marginal reef developed. Based on precise field measurements and microscopic observation, this paper describes the petrological characteristics and biological assemblages of the reef in detail and distinguishes 10 microfacies: small echinoderm wackestone, sponge floatstone, bound sponge bioliestone, bound sponge framestone, large echinoderm wackestone, red algal limestone, bioclastic grainstone, dasycladales wackestone, shelly wackestone, and microbialites. Sponge floatstone and bound sponge bioliestone are defined as toppled sponge limestone. Comparisons of the petrological characteristics and biotic association of toppled sponge limestone, bound sponge framestone and bioclastic wackestone and grainstone revealed that the toppled sponge limestone and the bound sponge framestone are similar in sponge content in terms of the types and contents of reef-dwellers, except that the sponge content is slightly lower, and the preservation state is mainly toppled for the former and upright or inclined for the latter. The toppled sponge limestone is dominated by tabular calcite, and the bound sponge framestone is dominated by fibrous calcite. The bioclastic wackestone and grainstone do not contain reef-building sponge organisms, and the bioclast content is very high and often dominated by a certain class, such as echinoderms, foraminifers, green algae or shells. The toppled sponge limestone below the framework, which was classified as fore-reef breccia or bioherm bafflestone-bindstone in previous studies, should be defined as reef-core sponge limestone deposited in situ that experienced serious post-karstification. The vertical evolution of the sedimentary facies of the reef is analyzed based on the microfacies and sedimentary environment. The toppled sponge limestone and the bound sponge framestone should be classified as reef core, which is the only subfacies of the reef facies. The underlying small echinoderm wackestone should be classified as the shelf facies, whereas the overlying bioclastic wackestone and grainstone should be classified as the open platform facies. These classifications represent a modification of the sedimentary facies subdivision of the Jiantianba reef in Lichuan, Hubei Province, South China, and provide a new reference model for the subdivision of the Permian calcisponge reefs on platform margin.