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1.
This paper is resulted from a systematic study of sporo-pollen of Ordos Basin of Northwest China has been found. Single spore assemblage in the Taiyuan Formation contains abundant Pteridophic and Pteridosperm spores and a few Gymnosperm pollen. 11 new species are described. New sporopollen taxa include, Punctatisporites gansuensis, Auritulinasporites ningxiaensis, Gulisporites discersus, Trivolites scabratus, Psomospora anulatus, Gravisporites rugu- laris, Velamisporites breviradidlis, Murospora strialatus, Foveomonoletes foveolatus, Cy- clogranisporites microtriagulus (comb. n.), Cycadopites pachyrrhachis (comb. n.) and Punatatisporites sp., Tantillus sp., Converrucosisporites sp., Columnisporites sp.. and Zono- spheridium reticulatoides and Z. granuloides of Acritarchs. There are some differences between spore assemblages of eastern and western parts of Ordos Basin. Western part is characteristic by more abundance of cingulum spores. The age of the microfossil is considered to be of the Late Carboniferous.  相似文献   

2.
陕西省鄂尔多斯盆地渭北油田中三叠统铜川组发现一枚牙齿化石。该枚牙齿具有如下特征:牙齿细长,外形呈圆锥形,齿冠基部横截面为圆形,齿冠整体较直,沿长轴稍微向后缘弯曲,齿冠表面无齿脊和锯齿分布,发育纵向延伸的沟槽状纹饰。通过与鳄型类、蛇颈龙类和离片椎类的牙齿比较,该标本可以归入离片椎类。这枚牙齿化石为这一类群在中三叠统铜川组的首次发现,代表了离片椎类在华北板块最晚的化石记录。  相似文献   

3.
《Palaeoworld》2016,25(4):581-599
Six Early Carboniferous brachiopod species in four genera of the Superfamily Spiriferoidea are described from the Qaidam Basin, northwestern China, including a new genus, Qaidamospirifer, and two new species: Grandispirifer qaidamensis and Qaidamospirifer elongatus. Additionally, a new genus, Triangulospirifer, is also proposed to replace Triangularia Poletaev, 2001 that was preoccupied by a Devonian molluscan genus.On the basis of the new material as well as published information, we have reviewed the taxonomic composition and the stratigraphic and palaeobiogeographic distributions of the three previously established genera from the viewpoint of palaeobiogeography. The study reveals that Grandispirifer has a relatively long stratigraphic range from the late Tournaisian to Serpukhovian. During this interval, the genus attained a wide geographical distribution, reaching Northwest China, western Yunnan of West China, Japan, as well as Iran and North Africa. Angiospirifer first occurred in western Europe in the Viséan, and later migrated to North Africa during the late Viséan. In the Serpukhovian, it migrated eastward, reaching the Donets Basin of Ukraine and the Qaidam Basin in Northwest China. Anthracothyrina evolved from Brachythyrina in North Africa in late Viséan, then dispersed north-westward to western and eastern Europe and, further eastward to the Qaidam Basin during the Serpukhovian.  相似文献   

4.
The genus Eretmophyllum, a characteristic and widespread taxon of the order Ginkgoales, is restricted in the Mesozoic floras of Eurasia. In China, although some specimens were assigned to Eretmophyllum based on gross leaf morphology, none have epidermal structure, which is essential for species delimitation within this genus. In this paper, we describe a new species, Eretmophyllum neimengguensis n. sp., from the Middle Jurassic Yan’an Formation of the Ordos Basin, China. This is the first record of the genus Eretmophyllum (Ginkgoales) from the Ordos Basin as well as from China based upon the gross leaf morphology and the epidermal structure. The new record significantly extends the stratigraphic and geographic distribution of Eretmophyllum in China and Eurasia. It also improves our understanding of its leaf morphology, epidermal structure, and past diversity. The taxonomic position and the stratigraphic and geographical range of the genus Eretmophyllum are discussed. Briefly, leaf morphological and epidermal characters of the new species, associated plant assemblages, and sedimentology indicate that the regional climate of the Ordos Basin was warm and humid with seasonal temperature and precipitation fluctuations in warm-temperate zone during the Middle Jurassic. Furthermore, given the relationship between the distribution/diversity of the genus and the climate, the genus Eretmophyllum may be confined to the warm-temperature climate, is intolerant of heat and frost, and can be considered as an indicator of humid and warm climatic conditions.  相似文献   

5.
Two Hipparion species, H. forstenae and H. hippidiodus from Gaojiashan locality in the Linxia Basin, Gansu, China are described in this paper, with the first presence of the former in the Linxia Basin. The lower cheek teeth of Hipparion from Gaojiashan bear deep ectoflexids, and after comparisons to other Chinese Hipparion fossils with deep ectoflexids, the mandibles with deep ectoflexids on the lower premolars suggest their attributions to H. forstenae. The presence of a deep ectoflexid on p2 may be interpretable as an intraspecifically variable feature in H. forstenae, and can also be found in H. dermatorhinum. Besides the Hipparion material, at least 8 species of large mammals occur at the Gaojiashan locality, including Adcrocuta eximia, Chilotherium wimani, Shansirhinus ringstroemi, Eucladoceros cf. proboulei, Palaeotragus cf. coelophrys, Giraffidae gen. et sp. indet., and the previously studied Promephitis hootoni and Eostyloceros hezhengensis. Although the sample from Gaojiashan shares five species with the Yangjiashan fauna, the Gaojiashan fossil assemblage may date to the Baodean because of the presence of H. forstenae. The overall taxonomic composition of the Gaojiashan assemblage at least suggests an approximate Baodean age, which would imply survival of C. wimani into the Baodean of the Linxia Basin.  相似文献   

6.
湖北秭归盆地中侏罗世陈家湾组孢粉组合的发现及其意义   总被引:1,自引:0,他引:1  
本文首次报道了湖北秭归盆地陈家湾组孢粉组合,该组合可归入Cyathidites minor-Classopollis Callialasporites为代表的组合,时代属中侏罗世。陈家湾组孢粉组合的特征反映了秭归盆地中侏罗世泄滩组、陈家湾组和沙溪庙组三个组的孢粉组合的面貌基本一致,仅早期组合与中、晚期组合略有差别。建议以Gyathidites minor-classopollis-callialasportes组合代表湖北西部——重庆地区中侏罗世孢粉组合,早期为Lunzisporites pallidus亚组合,中晚期为Converrrcosisporites venitus亚组合。根据孢粉植物群在本区侏罗纪垂直分布情况,提出早侏罗世时期属亚热带一热带炎热潮湿气候环境,植物生长茂盛;早侏罗世之后,潮湿的气候仍占主导地位,但出现了干旱的先兆;中侏罗世早期进入了半干旱阶段,随后即为炎热干旱的气候所笼罩;至晚侏罗世达到非常干旱的程度,植物种类十份单调,唯有掌鳞杉科植物占据着统治地位。  相似文献   

7.
Well-preserved dinosaur eggs from the Cretaceous Huizhou Formation in the Xiuning Basin, Anhui Province, China, are analysed in this paper. We describe a new oospecies, Similifaveoloolithus qiyunshanensis, based on several distinct characters of external morphology, size, eggshell thickness, and internal microstructure. Radial sections of this new oospecies show branched eggshell units with a fused layer near the outer surface, while numerous irregular pores and cones constitute a honeycomb pattern in tangential sections. The discovery of S. qiyunshanensis expands the distribution of Similifaveoloolithidae dinosaur eggs in China and provides new fossils for researching dinosaur eggshell formation mechanisms which are different from those of the currently known oofamilies. The dinosaur-egg-bearing strata in the Huizhou Formation have been dated to the early Late Cretaceous (Cenomanian-Turonian) on the basis of a similar dinosaur egg assemblage in the Tiantai Basin in Zhejiang Province. The eggs described in this paper are thought to have been laid in a buried nest while enrichment of trace elements in eggshells may have been caused by their ingestion into the body of the dinosaur producer. We suggest that the paleoclimate of this habitat was semi-arid to arid and that this environment was favourable for the preservation of eggs.http://zoobank.org/LSIDurn:lsid:zoobank.org:pub:9D63A51F-5A4B-4249-901D-42A33E9FA933  相似文献   

8.
A new biozonation is proposed for the Late Carboniferous strata of the northeastern Paraná Basin (São Paulo and Paraná States), based on well-preserved palynological assemblages recovered from outcrops and core samples retrieved from the Itararé Subgroup. Assemblages include forty-nine species of trilete spores and twenty-five pollen species. The oldest biozone, the Ahrensisporites cristatus Interval Zone (AcZ), in the basal portion of the Itararé Subgroup, includes eleven exclusive spore species, and is assigned a Pennsylvanian (late Bashkirian to Kasimovian) age. The overlying proposed biozone, the Crucisaccites monoletus Interval Zone (CmZ), dated late Pennsylvanian (Kasimovian to Gzhelian), ranges approximately from the top of the lower portion to the middle portion of the Itararé Subgroup, bears only one exclusive species of pollen. Both zones are characterized by the dominance of trilete spores and monosaccate pollen grains, including also few taeniate pollen grains. Furthermore, the basal Protohaploxypinus goraiensis Subzone of the Vittatina costabilis Interval Zone (VcZ) is broadly recognized for the first time in the upper portion of the Itararé Subgroup in the northeastern Paraná Basin. This subzone is attributed to the Early Permian (Early Cisuralian), and is characterized by the dominance of monosaccate pollen grains, a significant increase of taeniate grains (mainly Protohaploxypinus spp.), apart from the appearance of polyplicate pollen (Vittatina spp.). Reference sections and the main characteristics of the two new zones (AcZ and CmZ) are presented, along with a preliminary palynological correlation and discussion on their ages.  相似文献   

9.
A unique ichnofossil assemblage from Pennsylvanian-age sandstones near Eaton Rapids, Michigan, USA, comprises straight-to-curved traces preserved in convex hyporelief, with the transverse ridges and median grove associated with the ichnogenus Arthrophycus. The Michigan traces show some branching or pseudo-branching (also known from other Arthrophycus specimens) and are among the smallest structures (millimeters in diameter) attributed to this ichnogenus. The orientation of the Michigan Arthrophycus burrows is distinct from other ichnospecies of this taxon in the pronounced co-planar alignment of the burrows, as opposed to the multiplanar, interweaving, “bundled” nature typical of the ichnogenus. On this basis we assign the Michigan specimens to a new ichnospecies of Arthrophycus. The “paralleling behavior” of the new taxon may reflect a strategy of the tracemaker to avoid previous burrows and reflect differences in resource availability or current energy. This new taxon supports previous records of the occurrence of this ichnogenus in Upper Carboniferous strata.  相似文献   

10.
《Palaeoworld》2014,23(2):125-142
A Foliomena fauna is reported for the first time from the Tarim paleoplate, and stratigraphically from the Yinpingshan Formation (upper Katian, Upper Ordovician) of Querqueke, Kuruktag region, northeastern Tarim, southern Xinjiang, Northwest China. The fauna includes seven species of brachiopods, amongst which three are new and four indeterminate: Anomaloglossa? sp., Orbiculoidea? sp., Foliomena xinjiangensis n. sp., Sericoidea minuta n. sp., Kassinella tarimensis n. sp., Rostricellula? sp., and Anazyga? sp. These species formed a Sericoidea-Kassinella Association, characterized by very small and well-preserved brachiopods, and well-developed laminations in its hosted mudstone, indicating a deep water environment (corresponding to lower BA5 to BA6). The faunal and sedimentological features suggest its affinity to the typical Foliomena faunal group of deep water origin. Numerical analyses show that the Foliomena fauna in late Katian time differentiated into two major paleogeographically related groups, and the Tarim association has a close faunal affinity to the representatives of this fauna in South China, indicating an active faunal exchange between Tarim and South China before the end-Ordovician mass extinction.  相似文献   

11.
Three turtle shells from the Middle Jurassic Xintiangou Formation of Yunyang (Chongqing, China) are described and assigned to Xinjiangchelyidae (Testudines: Eucryptodira). This is the first report of turtle remains from the Xintiangou Formation, Sichuan Basin and represents the oldest known Xinjiangchelyidae. The assemblage includes two taxa, Protoxinjiangchelys sp. and Xinjiangchelyidae indet. This discovery extends the stratigraphical distribution of Xinjiangchelyidae and improves our knowledge about the early evolution of that family. It demonstrates that by the Middle Jurassic, at the time of deposition of the Xintiangou Formation, the group was already diversified in the Sichuan Basin.  相似文献   

12.
Dr. Karl Krainer 《Facies》1995,33(1):195-214
Summary A heretofore undocumented example of skeletal mounds formed by the dasycladacean algaAnthracoporella spectabilis is described from mixed carbonate-clastic cycles (Auernig cyclothems) of the Late Carboniferous (Gzhelian) Auernig Group of the central Carnic Alps in southern Austria. The massive mound facies forms biostromal reef mounds that are up to several m thick and extend laterally over more than 100 m. The mound facies is developed in the middle of bedded limestones, which are up to 16 m thick. These limestones formed during relative sea-level highstands when clastic influx was near zero. The mound facies is characterized by well developed baffler and binder guilds and does not show any horizontal or vertical zonation. Within the massive mound faciesAnthracoporella is frequently found in growth position forming bafflestones and wackestones composed of abundantAnthracoporella skeletons which toppled in situ or drifted slightly.Anthracoporella grew in such profusion that it dominated the available sea bottom living space, forming ‘algal meadows’ which acted as efficient sediment producers and bafflers. BecauseAnthracoporella could not provide a substantial reef framework, and could not withstand high water turbulence, the biostromal skeletal mounds accumulated in shallow, quiet water below the active wave base in water depths less than 30 m. The massive mound facies is under- and overlain by, and laterally grades into bedded, fossiliferous limestones of the intermound facies, composed mainly of different types of wackestones and packstones. Individual beds containAnthracoporella andArchaeolithophyllum missouriense in growth position, forming “micromounds’. Two stages of mound formation are recognized: (1) the stabilization stage when bioclastic wackestones accumulated, and (2) the skeletal mound stage when the sea-bottom was colonized byAnthracoporella and other members of the baffler and binder guilds, formingAnthracoporella bafflestones and wackestones of the mound facies. A slight drop in sea-level led to the termination of the mound growth and accumulation of organic debris, particularly calcareous algae, fusulinids, crinoids and bryozoans, forming well bedded limestones, which overlie the mound facies  相似文献   

13.
Vertebrate microremains from the Late Devonian-Early Carboniferous of the Carnic Alps are predominantly chondrichthyan, with minor placoderm and actinopterygian remains. The faunas are sparse and, with very few exceptions, occur only in conodont-rich pelagic limestones (Pramosio Limestone) representative of the palmatolepid-bispathodid conodont biofacies. Phoebodont and jalodont chondrichthyans, also reflecting open-ocean environments, predominated during the Famennian, and eventually symmoriids seem to predominate during the Early Carboniferous. The presence of Siamodus in this assemblage gives a new locality for this genus known from few regions in the world and allows confirming its stratigraphical range (limpidus Zone) and its relation to deep-water environments. The Late Devonian vertebrate faunas are tropical and cosmopolitan, having much in common with coeval taxa from the North-Gondwanan margins and Asian terranes. Composition of the vertebrate faunas is consistent with the Carnic Alps terrane having occupied a position intermediate between Gondwana and Laurussia, as hypothesized by various authors, but because of sparsity of the taxa represented and the pronounced cosmopolitan nature of both the conodont and vertebrate faunas, the data are not compelling.  相似文献   

14.
About 98 species of fossil spores and pollen referred to 55 genera from the Upper Carboniferous Yanghugou Formation in Zhongwei, Ningxia have been studied. Two sporopollen assemblage zones are recognized in ascending order as follows: 1. Laevigatosporites medius-Cyclogranisporites aureus (MA) zone: This assemblage corresponds to the lower part of the Yanghugou Formation, and is characterized by the predominance of pteridophyfic spores and the relative abundance of gymnospermous pollen. Azonotriletes and monoletes are dominant, while zonates are of importance. The most common species are Leiotriletes spp., Cyclogranisporites aureus Potoni6 et Kremp, Granulatisporites granulatus Ibrahim, Microreticulatisporites concavus Butterworth et Williams, M. nobilis (Welcher) Knox, Triquitrites bransonii Wilson et Hoffmeister, Dictyotriletes bireticulatus (Ibrahim) Smith et Butterworth, Ahrensisporites guerickei (Horst) Potonie et Kremp, Lycospora spp., Crassispora kosankei (Potonie et Kremp) Bharadwaj, Cirratriradites saturni (Ibrahim) Schopf, Wilson et Bentall, Laevigatosporites spp., Columinisporites ovalis Peppers, Florinites junior Potnie et Kremp and Vesicaspora wilsonii (Schemel) Wilson et Venkatachata. This assemblage is comparable with those of the Yanghugou Formation in Baiyantaohai of Inner Mongolia (Yu, 1983), the 8th zone of North China by Gao (1979), the Triquitrites sinani-Cirratriradites saturni (SS) Zone and the Microreticulatisporites nobilis-Florinites junior (NJ) Zone of West Europe, which are considered corresponding to Westphatian A-B in age. 2. Torispora seuris-Punctatisporites hians (SH) zone: This assemblage is equivalent to the upper part of the Yanghugou Formation, and is also characterized by dominance of pteridophytic spores and subdominance of gymospermous pollen. In addition to the most commen species mentioned above, the important taxas in the present assemblage comprise Punctatisporites hians Wang, Gulisporites cochlearius Imgrund, Verrucosisporites kaipingiensis Imgrund, Endosporites globiformis (Ibrahim) Schopf, Wilson et Bentall, Densosporites anulatus (Loose) Smith et Butterworth, D. reticuloides Ouyang et Li, Simozonotriletes labellatus Wang, Torispora securis Balme, Thymospora thiessenii (Kosanke) Wilson et Venkatachala, Pit yos porites west phalensis Williams and Plat ysaccus, Illinites, C ycadopites, etc. This zone compares closely with those of the upper part of the Yanghugou Formation in Hengshanbu (Wang Hui, 1984) and Ordos Basin (Geng, 1985), the Benxi Formation in Shanxi (Liao, 1987; Ouyang and Li, 1980; Gao, 1979), as welll as Torispora securis-T, laevigata (SL) Zone and Thymospora obscura-T, thiessenii (OT) Zone of West Europe. Therefore, the present SH Zone should be referred to Westphalian C-D in age. The Westphalian palynofiora in Zhongwei is dominated by Filicopsida and pteridospermopsida; Sphenopsida and lycopsida occupy the subdominant position, while Cordaitopsida and Coniferopsida do not develop well. This palynofiora indicates a tropical-subtropical warm and humid paleoclimate.  相似文献   

15.
The type specimens of the Jurassic turtles from the Sichuan Basin (China) previously referred to plesiochelyid Plesiochelys are revised, which confirm that they belong to the family Xinjiangchelyidae. The study of a large number of additional shell material shows, as the dominant group, the Xinjiangchelyidae were greatly diversified in the Late Jurassic of the Sichuan Basin. By the absence of mesoplastron and other shell characters, Chengyuchelys baenoides is moved to Xinjiangchelyidae and considered as a valid taxon. Of the xinjiangchelyids from the Late Jurassic of Sichuan Basin, four genera are recognized: Chengyuchelys, Tienfuchelys, Yanduchelys and cf. Protoxinjiangchelys. The phylogenetic analysis results in that Chengyuchelys includes C. baenoides, C. latimarginalis and C. radiplicatus, and Tienfuchelys consists of T. tzuyangensis, T. chungkingensis and T. zigongensis. All xinjiangchelyids from the Sichuan Basin are more primitive than Xinjiangchelys in the plastron sutured to the carapace.  相似文献   

16.
17.
This paper deals with a few fossil plants of the Jiuligang Formation found ill Jingmen-Dangyang Basin, western Hubei, China. Of which a few are related to paleozoic taxa, such as Compsopteris laxivenosa sp. nov. and C. xiheensis (Feng) comb. nov., Besides those, Paradrepanozamites dadaochangensis Chen, emend, nov. and P. minor sp. nov. are described. The geological age of the Jiuligang Formation is assigned to Carnic to early Noric.  相似文献   

18.
Upper Paleozoic sedimentary sequences from several localities of the northeastern Paraná Basin were sampled for paleobotanical and palynological studies. Well-preserved terrestrial assemblages from samples of Campinas, São Paulo State, from an outcrop at the 97 km mark on the Bandeirantes Highway, located at the Municipality of Campinas, São Paulo State were recorded where fertile bryophytes and megaspores were previously also found. The Campinas palynoflora is composed of 23 species of bryophytic and pteridophytic spores, 16 species of pollen grains, and one algae (Botryococcus braunii Kützing). Among the sporomorphs, Reticulatisporites asperidictyus Playford and Helby is described for the first time from the Paraná Basin. Assemblages bear diagnostic species of the Ahrensisporites cristatus Interval Zone, such as Anapiculatisporites argentinensis Azcuy, Cristatisporites inordinatus (Menéndez and Azcuy) Playford, and Psomospora detecta Playford and Helby, of Late Carboniferous age (Pennsylvanian). Palynological content suggests a glacio-deltaic/lacustrine environment of deposition. This is supported by lithological data and by the absence of marine palynomorphs.  相似文献   

19.
《Geobios》2014,47(1-2):57-74
A moderate diversity biota of foraminifers, algae and calcareous microproblematica is recorded from the Lower Carboniferous Yindagindy Formation within the intracratonic Southern Carnarvon Basin in Western Australia. Very shallow metahaline to hypersaline conditions are suggested. The palaeobotanical components are sporadic calcitarcha, tuberitinaceans, codiaceans Orthriosiphon? sp. 1, dasycladaleans? Koninckopora tenuiramosa, and algosponges Issinella devonica, Serrisinella cf. serrensis, Issinella? sp. 1, Kamaena cf. awirsi, Proninella? sp. and Stacheoides spp. The foraminiferal assemblage is dominated by a new koktjubinid taxon: Praekoktjubina yindagindyensis nov. gen., nov. sp. Subordinate associated foraminifers are more sporadic Salpingothurammina? sp. 1, Plectinopsis michelseni nov. gen., nov. sp., Rectopravina multifida nov. gen., nov. sp. (with 4 morphotypes), and scarce Endothyra spp. Despite many of these taxa being endemic, a middle Visean age is probable, based on: (1) the maximum global geographic extent of K. tenuiramosa reached during the middle Visean, (2) the disappearance of Plectinopsis nov. gen. in Palaeotethys and the Urals, and (3) the first occurrence of Praekoktjubina nov. gen. in Palaeotethys. An age no older than the middle Visean is supported by sparse conodonts from the Formation and comparison to episodes of carbonate deposition in the Bonaparte Basin, further north in the East Gondwana rift system. Absence of middle Visean archaediscoids may be due to high salinity. The following algal and foraminiferal families and superfamilies are emended: Scribroporellaceae (a lectotype is selected for Orthriosiphon saskatchewanense); Palaeospiroplectamminidae (due to the creation of Plectinopsis nov. gen.); Haplophragminoidea (due to the creation of Rectopravina nov. gen.); and Globivalvulinoidea and Koktjubinidae (due to the creation of Praekoktjubina nov. gen.).  相似文献   

20.
The phylogeny and taxonomy of the brachiopod family Linoproductidae are revised. The change in the distributional pattern of spines and distinctive structure of the median lobe of the cardinal process are shown to be the main apomorphies in the family evolution. A new subfamily, Linispininae, and the included new genera, Linispinella and Linispinus, are described. In the nominotypical subfamily Linoproductinae, a new genus Linoproductoides and two new species included in this genus are described from the Vereiskian deposits of the Moscow Region. The new species Linispinus riparius (Trautschold), L. longus sp. nov., and L. staricensis (Ivanov) are described from the Kashirskian deposits. Another new species is tentatively described as “Linoproductus” kabanovi.  相似文献   

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