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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 laboratory of Palaeobiology & stratigraphy, {4. institute of Ge-ology and palaeontology, chinese academy of sciences, {4. 210008, china 1. Department of geology Peking University 100871 Beijing China 2. laboratory of Palaeobiology & stratigraphy 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.

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 geology and palaeontology, chinese academy of sciences State Key laboratory of Palaeobiology and stratigraphy, {4. 210008, china 1. nanjing institute of geology and palaeontology Chinese Academy of Sciences State Key laboratory of Palaeobiology and stratigraphy 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 {4. of Palaeobiology and stratigraphy, nanjing institute of geology and palaeontology, chinese academy of sciences, nanjing 210008, china 1. Faculty of Earth sciences and Mineral Resources China University of Geosciences 100083 Beijing China 2. State Key laboratory of Palaeobiology and stratigraphy 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.

Lower Cretaceous angio-sperm leaf from Wuhe in Anhui,china

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chinese Science Bulletin 2003年第6期48卷 611-614页

作者： LI Haomin nanjing institute of geology and palaeontology, chinese academy of sciences, nanjing 210008, china nanjing institute of geology and palaeontology Chinese Academy of Sciences China

A new early angiosperm leaf species is reported from the Xinzhuang Formation in Wuhe County, Anhui Province. It is probably of Barremian or slightly later in geological age. The fossil leaf is small, no more than 0.6 cm both in length and in width. The leaf veins are well preserved and clearly visible under a low power microscope. Leaf ar-chitectural analysis shows that such a leaf should belong to the first leaf rank of Hickey, i.e. the most primitive one. There are no early angiosperm leaves published completely similar to ours. A new species name of Dicotylophyllum minutissimum sp. nov. is established for the present leaf fos-sils.

关键词：安徽下白垩统早期被子植物叶片结构叶片化石

The discovery of aeschnidiid nymphs (Aeschnidiidae, Odonata, Insecta)

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chinese Science Bulletin 2000年第11期45卷 1031-1038页

作者： ZHANG Junfengnanjing institute of geology and palaeontology,{4., nanjing 210008, china nanjing institute of geology and palaeontology Chinese Academy of Sciences Nanjing China

Aeschnidiid nymphs are here first identified and described, and its phylogenetic relationship and bioecological characteristics are deduced. The nymphs known from china, Mongolia, Russia and Brazil and arranged in the family Aeschnidiidae are, in fact, unrelated to this group. All the known five chinese species in four genera which were erected based on fossil nymphs and placed in the family Gomphidae may be transferred in Aeschnidiidae and merged into one alone, the Sinaeschnidia cancellosa. It is a geographically widespread species from the 'Jehol biota' of East Asia and appeared in the latest Late Jurassic age.

关键词： Jehol biota Aeschnidiidae dragonfly nymphs.

Discovery of Cathaysiodendron Lee from the Early Carboniferous of Jingyuan,Gansu,western china

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Progress in Natural Science:Materials International 2004年第10期14卷 63-66页

作者： WANG Jun and WU Xiuyuan (nanjing institute of geology and palaeontology,{4. academy of sciences,nanjing210008,china) chinese Acad Sci Nanjing Inst Geol & Palaeontol Nanjing 210008 Peoples R China

As one of the representative members of the Late Palaeozoic Cathaysian flora,Cathaysiodendron has been previously recorded from the Early Permian Taiyuan and Shanxi Formations in north *** species of Cathaysiodendron presented here are from the lower member of Chouniugou Formation of Ciyao,Jingyuan,*** overlying marine beds yield fusulinids that are of Visean age in western Europe and conodonts of the Datang Stage in south china,so that the age of the bed containing Cathaysiodendron as Visean,Early Carboniferous,is well *** a record of Cathaysiodendron is significant in terms of Carboniferous phyto-geography and the evolution of the Cathaysian Lepidophytes.A new species,Cathaysiodendron jingyuanense Wang&Wu *** described and a second one mentioned.

关键词： Cathaysiodendron Early Carboniferous Visean Cathaysian flora

Preface——Jurassic of china and Environs: stratigraphy, Basin History, and Paleoenvironment

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Science china Earth sciences 2009年第12期52卷 1871-1872页

作者： SHA JinGeng LPS, nanjing institute of geology and palaeontology, chinese academy of sciences, nanjing 210008, china LPS Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China

The Jurassic is a geologically very complicated period in Earth history, spanning from 200 to 14. Ma. The Pangean supercontinent and even the Gondwana-land broke up, and the violent circum Paleo-Pacific (Yanshan) or... 详细信息

关键词： Preface and Paleoenvironment stratigraphy Jurassic of china and Environs Basin History

Yangtzedonta and the early evolution of shelled molluscs

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chinese Science Bulletin 2001年第24期46卷 2103-2106页

作者： QIAN Yinanjing institute of geology and palaeontology,{4., nanjing 210008, china nanjing institute of geology and palaeontology Chinese Academy of Sciences Nanjing China

The holotype of Yangtzedonta Yu, 1985 and its type species, Y. primitiva Yu, 1985, is an incomplete specimen of Xianfengella prima He et Yang, 1982. Therefore, based on the principle of priority, the names Yangtzedonta and Y. primitiva Yu (1985) should be abandoned. The fact that ventral valve of Xianfengella is bilaterally symmetrical indicates that they are not the left valve of a bivalved mollusc, as originally proposed by Yu. At present, the oldest certain bivalve is Xianfengoconcha elliptica Zhang, which occurs in the Early Cambrian Qiongzhusi Stage in china. The oldest known rostroconch is Heraultipegma yunnanensis He et Yang, which first occurs in the third small shelly fossil assemblage zone of the Early Cambrian Meishucunian Stage. The oldest known monoplacophoran, Maikhanella pristinis (Jiang), first occurs in the first small shelly fossil assemblage zone (Meishucunian Stage). Evidence derived from analyses of shell morphology, mode of growth, histology, and stratigraphic occurrence suggests

关键词： Yangtzedonta bivalves Xianfengella brachiopods enig- matic fossil.

Discovery of agglutinated foraminifers from the Longzhaogou Group in eastern Heilongjiang Province

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Science china Earth sciences 2004年第2期47卷 122-127页

作者： LI Gang & YU Shanmao1. State Key laboratory of paleobiology stratigraphy, nanjing {4. of geology and Paleontology, chinese academy of sciences, nanjing 210008, china 2.108th Coal-prospecting Team of Geological Bureau, NE china and Inner Mongolia Coal Company, Jixi 158100, china Correspondence should be addressed to Li Gang (email: gangli@***) 1. State Key laboratory of paleobiology stratigraphy Nanjing Institute of Geology and Paleontology Chinese Academy of Sciences 210008 Nanjing China 2. 108th Coal-prospecting Team of Geological Bureau NE China and Inner Mongolia Coal Company 158100 Jixi China

The low diversity agglutinated foraminifers are recovered from the Qihulin Formation of the Longzhaogou Group in eastern Heilongjiang, china. The foraminiferal fauna consists of 9 species of 5 genera. The common members are Cribrostomoides nonioninoides (Reuss), Haplophragmoides concavus (Chapman), H. gigas minor Nauss. Although the diagnostic zonal taxa are absent in the agglutinated fauna, according to the global stratigraphic distribution of the above-mentioned species, and the associated Pseudohaploceras ammonite fauna, the foraminiferal fauna may be of a Barremian-Aptian (Early Cretaceous) age.

关键词： Early Cretaceous, agglutinated foraminifers, Longzhaogou Group, eastern Heilongjiang, china.