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Two new species of Vestrogothia (Phosphatocopina, Crustacea) of Orsten-type preservation from the Upper Cambrian in western Hunan, South china

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Science china Earth sciences 2009年第6期52卷 784-796页

作者： ZHANG HuaQiao1,2.& DONG XiPing1,2.1 School of Earth and Space sciences,Peking University,Beijing 100871,china 2.State Key {2. of palaeobiology and stratigraphy,nanjing institute of geology and palaeontology,chinese academy of sciences,nanjing 2.0008,china School of Earth and Space sciences Peking University Beijing 100871 China State Key laboratory of palaeobiology and {2. Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China

Although fossils of Orsten-type preservation represented by Skaracarida and Phosphatocopina were first reported from the Middle and Upper Cambrian in western Hunan, South china in 2.05, diversified phosphatocopine species have never been appropriately described and elucidated in terms of their evolutionary relationships. Here, we described two new species of Phosphatocopina, Vestrogothia anterispinata sp. nov. and V. bispinata sp. nov. The evolutionary relationship among all the valid species of Phosphatocopina is discussed and the phylogeny of Phosphatocopina is reestablished using cladistic analysis. Accordingly, phosphatocopines primitively evolved along two lineages: one evolved towards the emergence of lobes; the other evolved towards the emergence of dorsal spines. Respectively, lobes originated independently three times, and dorsal spines originated only once. With regard to the dorsal rims, interdorsum originated first, whereas dorsal furrow originated independently twice on the basis of interdorsum. Probably Hesslandona may represent a polyphyletic group, whereas Vestrogothia a monophyletic group.

关键词： fossils of Orsten-type preservation Vestrogothia Phosphatocopina Crustacea evolution phylogeny Cambrian Hunan

On the evolution and histology of some Cambrian protoconodonts, paraconodonts and primitive euconodonts

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Science china Earth sciences 2004年第7期47卷 577-584页

作者： DONG Xiping Department of geology, Peking University, Beijing 100871, china {2. of palaeobiology & stratigraphy, nanjing institute of Ge-ology and palaeontology, chinese academy of sciences, nanjing 2.0008, china 1. Department of geology Peking University 100871 Beijing China 2. laboratory of palaeobiology & {2. Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences 210008 Nanjing China

Previous reports on the morphological evolution of protoconodonts and paraconodonts are reviewed. The evolutionary trends exhibited by species of the protoconodont genus Gapparodus and the paraconodont genus Westergaadodina are discussed. Based on the present study on histology, genus Paibiconus is protoconodont, while genus Yongshunella is paraconodont (fig. 1 (a)). However, the nature of Huayuanodontus has not been fully understood so far. Recently, the transitional form New Gen. Sensu Miller, 1980 of late Late Cambrian has been found in Hunan Province, South china. It is considered as the Sister-Group of Proconodontus. Moreover, another kind of transitional form of middle Late Cambrian and late Late Cambrian between Prooneotodus notundatus and Pnoconodontus, which looks like Prooneotodus notundatus in gross morphology, but has anterior and posterior costae, has also been found in Hunan, South china. This kind of transitional form is believed to be probably the real intermediate link between Prooneotodus rotundatus and Pnoconodontus, and Prooneotodus rotundatus is most probably the ancestor of Proconodontus. The two transitional forms noted above are all euconodonts by the study of their histology. Unlike the euconodonts of Post-Cambrian, the evolutionary relationships among the species of protoconodonts, paraconodonts and the primitive euconodonts could not be made clear without the histological study on them.

关键词： protoconodonts, paraconodonts, evolution, histology, Cambrian.

Developmental sequence of Cambrian embryo Markuelia

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chinese Science Bulletin 2007年第7期52卷 929-935页

作者： DONG XiPing1,2.1 School of Earth and Space sciences, Peking University, Beijing 100871, china {2., nanjing institute of geology and palaeontology, chinese academy of sciences, nan-jing 2.0008, china (email: dongxp@***) School of Earth and Space sciences Peking University Beijing 100871 China

Based on more exquisitely preserved specimens of Markuelia hunanensis recently recovered from Middle and Upper Cambrian in western Hunan and in the light of Synchrotron radiation X-ray tomo-graphic microscopy, the developmental sequence from cleavage through organogenesis to the pre-hatching of Cambrian embryo Markuelia, especially the developmental sequence during the pre-hatching stage, i.e. from the earliest period when the scalids and tail spines only took shape to the latest period (just about hatching), is established. This developmental sequence provides a pattern of embryonic development during the pre-hatching stage, which has not been established in the living scalidophorans (priapulids, loriciferans and kinorhynchs). Thus, it not only enriches our knowledge on the embryonic development of the extant descendants of Markuelia, but also opens a new window to the evolution and development of the animal.

关键词：寒武纪蠕虫化石胚胎发育序列两侧对称动物胚胎

Palaeogene fossil Populus leaves from Lanzhou Basin and their palaeoclimatic significance

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chinese Science Bulletin 2004年第14期49卷 1494-1501页

作者： SUN Bainian1,2. YAN Defei1, XIE Sanping1, CONG Peiyun1, XIN Cunlin1 & YUN Fei1 1. Key laboratory of Western china抯 Environmental Systems of the Ministry of Education, Lanzhou University, Lanzhou 730000, china 2. State Key laboratory of palaeobiology and stratigraphy, nanjing institute of geology and palaeontology, chinese academy of Sci-ences, nanjing 2.0008, china Key laboratory of Western china''s Environmental Systems of the Ministry of Education Lanzhou University Lanzhou 730000 China State Key laboratory of palaeobiology and {2. Nanjing Institute of Geology and Palaeontolog Chinese Academy of Sci- ences Nanjing 210008 China

An angiosperm compression flora is found in Palaeogene from Lanzhou Basin and the cuticular analysis of Populus davidiana Dode in the flora is carefully made. Fur-thermore, the fossil cuticles are compared with the epidermal structures of extant Populus leaves growing in different en-vironments, i.e. moist, semimoist, and semiarid to arid cli-matic regions. The present experiments indicate that mature leaves of P. davidiana show leaf size from big to small, leaf cuticles from thick to thin and anticlinal walls of epidermal cells from faintness to clarity along with the increase of lati-tudes of the plant distributions, the climatic variation from moist to arid, the annual precipitation from more to less and the annual mean temperature from high to low. The fossil P. davidiana differs from the specimens collected from Shandan in semiarid to arid climatic regions but closely resembles the Wushan leaves in a semi-moist climatic area in a lot of fea-tures. In a word, the new research may reflect that the flora lives in a semi-moist climatic environment. The present dis-covery of compression of Paleogene Populus davidiana is of great significance to studying vegetation types, climatic and environmental changes during the primal uplifting of the Qinghai-Tibet Plateau.

关键词：古气候兰州盆地山杨化石角质层早第三纪被子植物

A new method to prepare clean cuticular membrane from fossil leaves with thin and fragile cuticles

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Science china Earth sciences 2011年第2期54卷 223-227页

作者： WANG Li1,2.& LENG Qin1,3 1 State Key laboratory of palaeobiology and {2.,nanjing institute of geology and palaeontology,chinese academy of sciences,nanjing 2.0008,{12. 2.Graduate School of chinese academy of sciences,Beijing 100049,{12. 3 Department of Science and Technology,Bryant University,Smithfield RI 02.17,USA 1. State Key laboratory of palaeobiology and {2. Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China2. Graduate School of Chinese Academy of Sciences Beijing 100049 China3. Department of Science and Technology Bryant University Smithfield RI 02917 USA

Leaf cuticle analysis has long been a powerful tool for fossil plant identification, systematics, and palaeoclimatological recon- struction. In recent decades the application of stomatal frequency data that are relied on precise calculation of stomata on plant fossil cuticles to reconstruct ancient atmospheric CO2.concentration made the preparation of cuticular membrane with sufficient size a critical technique in palaeoclimatological research. However, for plants with originally thin and fragile cuticles, e.g., most deciduous plants, conventional techniques sometimes fail to obtain cuticular membranes with sufficient size, or sometimes unable to recover any. This has largely hampered the usage of fossil cuticle analysis in palaeobotanical and palaeo- climatological research. Here, we describe a new method using clear nail polish as a medium to ＂strengthen＂ the originally thin and fragile cuticles prior to maceration procedures. We demonstrate the method by using middle Eocene Metasequoia fossils that were notorious for the difficulty of recovering large-sized clean cuticular membranes due to their thin and fragile nature. Metasequoia, with well-documented and widely-distributed fossil records since the Late Cretaceous and with a living repre- sentative, 114. glyptostroboides, as a comparative reference, bas been widely used as a model genus for the study of evolution of plants, palaeoclimatological reconstruction, and plant adaptation to climate changes. But its deciduous habit produces thin cuticles and makes the preparation of clean cuticular membranes a tedious process. The new method successfully allows us to recover its delicate cuticular membranes with sufficient sizes for SEM observation and stomatal frequency analysis.

关键词： fossil leaf cuticle Metasequoia new method thin and fragile cuticle SEM observation stomatal frequency CO2

Early-Mid Ordovician brachiopod diversification in South china

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Science china Earth sciences 2005年第5期48卷 662-675页

作者： ZHAN Renbin, RONG Jiayu, CHENG Jinhui & CHEN Pengfei nanjing institute of {2. and palaeontology, chinese academy of sciences State Key laboratory of palaeobiology and stratigraphy, nanjing 2.0008, china 1. nanjing institute of {2. and palaeontology Chinese Academy of Sciences State Key laboratory of palaeobiology and {2. 210008 Nanjing China

Affected by paleogeographic position, paleoclimatic condition and depositional environments, the increase of the Early-Mid Ordovician brachiopod diversity of South china commenced at the beginning of the Ordovician (early Tremadoc), accelerated from the Tetra- graptus approximatus Biozone (base of Arenig), and reached its first acme in the Didymograptus eobifidus Biozone (mid early Arenig) when the number of brachiopod genera was over 7 times as great as that at the start of the Ordovician. This was the first radiation in the history of brachiopod macroevolution in South china, which occurred nearly 5 graptolitic biozones earlier than the global trend of the great Ordovician biodiversification (in the lower part of the Undulograptus austrodentatus Biozone). It is also characterized by (1) the origination or first occurrences of some major groups, such as the punctate dalmanelloids and the pseudopunctate stro- phomenoids including Plectambonitoidea (cardinal process simple or absent) and Stro- phomenoidea (cardinal process bilobed) in South china; (2. niche expansion, particularly in the first occupation of deeper water benthic regimes by the Euorthisina-Nocturnellia Association developed at Houping, Chengkou, northern Chongqing; and (3) the differentiation of brachiopod faunas under different environmental conditions. The gradual and increasing separation from Gondwana may have been one of the factors responsible for the radiation in South china.

关键词： biodiversity, evolutionary radiation, brachiopods, Early-Mid Ordovician, South china.

Criteria for defining and recognizing the various orders of sequences in outcrop sequence stratigraphy

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Science china Earth sciences 2004年第7期47卷 618-629页

作者： WANG Xunlian Faculty of Earth sciences and Mineral Resources, china University of Geosciences, Beijing 100083, china State Key laboratory of palaeobiology and stratigraphy, nanjing institute of geology and palaeontology, chinese academy of sciences, nanjing 2.0008, china 1. Faculty of Earth sciences and Mineral Resources China University of Geosciences 100083 Beijing China 2. State Key laboratory of palaeobiology and {2. Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences 210008 Nanjing China

The regional distribution in different depositional facies belts is here regarded as an important criterion for defining and recognizing the various orders of sequences. The third-order sequence is possibly global in nature, which may be discerned in different depositional facies belts in one continental margin and can be correlated over long distances, sometimes even worldwide. Commonly, correlation of subsequence (fourth-order sequence with time interval of 0.51.5 Ma) is difficult in different facies belts, although some of them may also be worldwide in distribution. A subsequence should be able to discern and correlate within at least one facies belt. The higher-order sequences, including microsequence (fifth-order sequence) and minisequence (sixth-order sequence), are regional or local in distribution. They may reflect the longer and shorter Milankovitch cycles respectively. Sequence and subsequence are usually recognizable in different facies belts, while microsequence and minisequence may be distinguished only in shallow marine deposits, but not in slope and basin facies deposits. A brief discussion is made on the essential conditions for correct identification of sequences, useful methods of study, and problems meriting special attention in outcrop sequence stratigraphy.

关键词： outcrop sequence stratigraphy, facies belt, sequence, subsequence, microsequence, minisequence, meter-scale cyclothem, Milankovitch cycle.

A restudy of Oryctocephalus indicus (Reed,1910)

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Progress in Natural Science:Materials International 2006年第11期16卷 1177-1182页

作者： ZHAO Yuanlong~1**, YUAN Jinliang~2. PENG Shanchi~ 2.3 , YANG Xinglian~1, PENG Jin~1, LIN Jihpai~4, and GUO Qingjun~5(1. College of Resource and Environment of Guizhou University, Guiyang 550003, china 2. nanjing {2. of geology and palaeontology, chinese academy of sciences, nanjing 2.0008, china 3. State Key laboratory of Papaeobiology and stratigraphy, nanjing {2. of geology and palaeontology, nanjing 2.0008, china 4. Department of Geological Science, Ohio State University, Columbus, OH 432.0, USA 5. {2. of Geochemistry, chinese academy of sciences, Guiyang 550002. china) College of Resource and Environment of Guizhou University Guiyang 550003 China nanjing institute of {2. and palaeontology Chinese Academy of Sciences Nanjing 210008 China State Key laboratory of Papaeobiology and stratigraphy Nanjing Institute of Geology and Palaeontology Nanjing 210008 China Department of Geological Science Ohio State University Columbus OH 43210 United States institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

Restudy on morphology of Oryctocephalus indicus (Reed, 1910), based on specimens from Guizhou, china and Nevada USA, suggests that the subspecies regarded previously as Oryctocephalus indicus indicus (Reed, 1910), O. indicus latus Zhao et Yuan 2.02. and O. indicus kobayashi Saito, 1934, are synonymous, and Oryctocephalus americanus Sundberg et McCollum, 2.03 is a similar form of O. indicus. Oryctocephalus indicus is rediagnosed as having a glabella that is subconical in outline and tapering forward slightly; a thorax that comprises 12.segments, and a small pygidium that bears 2.3 axial rings with a terminal piece and a postaxial ridge. Oryctocephalus indicus is widely distributed in eastern Guizhou and ranges through a great interval of Kaili Formation. Its first appearance is almost identical with these events of trilobite extinction-recovery occurring at the end of the Early Cambrian, the alternation of acritach assemblages, the change of trace elements (REE) and stable isotopes (carbon) at the Wuliu-Zengjiaya section. As one of the key forms for defining the traditional Lower-Middle Cambrian boundary (the base of Cambrian Series 3 and Stage 5 in the new Cambrian chronstratigraphic standard), O. indicus has received detailed study and has more advantages than other species such as Ovatoryctocara granulata Tchernysheva, 1962.or Arthricocephalus chauveaui Bergeron, 1899.

关键词： Oryctocephalus indicus restudy Kaili Formation Cambrian Guizhou china.

Jianshangou Bed of the Yixian Formation in West Liaoning, china

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Science china Earth sciences 2005年第3期48卷 298-312页

作者： CHEN Peiji1,2. WANG Qifei1, ZHANG Haichun1,2. CAO Meizhen1, LI Wenben1, WU Shunqing1 & SHEN Yanbin1 1. nanjing institute of {2. and Palaeontolgoy, chinese academy of sciences, nanjing 2.0008, china 2. State Key laboratory of palaeobiology and stratigraphy, nanjing 2.0008, china 1. nanjing institute of {2. and Palaeontolgoy Chinese Academy of Sciences 210008 Nanjing China 2. State Key laboratory of palaeobiology and {2. 210008 Nanjing China

The Jianshangou Bed is a set of fossil-bearing sedimentary interlayers of the basal volcano-sedimentary deposits of Yixian Formation in western Liaoning. It is rich in volcanic composition and consists of upper and lower grey-black shale, basal sandy conglomerate, top tuffaceous sandstone, middle massive silty mudstone and siltstone, as well as andesite, with a thickness of 2.—95 m. The Jianshangou Bed is famous all over the world for its bearing early birds, angiosperms and feathered dinosaurs, and it also yields bivalves, gastropods, con- chostracans, ostracods, shrimps, insects, fish, amphibians, primitive mammals and other reptiles. These fossils are typical representatives of the Late Mesozoic Jehol Biota from eastern Asia. The Chaomidianzi and Sihetun formations, proposed in recent years, are regarded as the junior synonyms of the Jianshangou Bed. The Jehol Biota is endemic to eastern Asia, however, it has a large geographic distribution, more than half of the European territory. Many species of the biota have close relationships with the late Jurassic European counterparts, e.g. both Confuciusornis and Archaeopteryx are primitive birds, Sinosauropteryx has a similar skeleton construction with Compsognathus, the ostracode assemblage from the Jianshangou Bed is close to that from the Purbeck Bed in England, and Aeschnidium occurs in both the Jianshangou Bed and Solnhofen of Germany. Based on the biostratigraphic correlation, the Jianshangou Bed is more probably late Tithonian in age. The latest zircon U-Pb dating of the Jianshangou Bed gives 12..2.Ma, and is close to the feldspar Ar/Ar dating of 12..6 Ma. A glauconite dating of 12. Ma was once got from England near the J/K boundary within the Purbeck Bed, so it is still problematic to place the J/K boundary at 130, 135, 137, 142.or 145.5 Ma in the International Stratigraphic Charts.

关键词： Yixian Formation, Jianshangou Bed, Jehol Biota, J/K Boundary.