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1.
Junggar is one of the most important areas in the study of the Upper Devonian and Lower Carboniferous in the Junggar-Hinggan Stratigraphic Region. Nevertheless, abundant benthic fossils await modern taxonomic studies. In this paper, six genera and eight species of Famennian spiriferide brachiopods are described from the Duguer Member and its equivalents of the Hongguleleng Formation in western Junggar, adding new data to the Rugaltarostrum Subassemblage of the “Palaeospirifer”–Megalopterorhynchus Brachiopod Assemblage of this area. Five previously recognized species within this subassemblage are revised, including: Cyrtospirifer junggarensis F.M. Zhang [now Ulbospirifer? junggarensis (F.M. Zhang)]; Tenticospirifer tenticulum transversus F.M. Zhang [now Cyrtospirifer transversus (F.M. Zhang)]; Tenticospirifer koketekensis F.M. Zhang [now Cyrtospirifer koketekensis (F.M. Zhang)]; Mucrospirifer quadratus F.M. Zhang (now “Mucrospiriferquadratus F.M. Zhang); and Mucrospirifer bouchadi (Muir-Wood) (now Tylothyris cf. novamexicana Stainbrook). Three additional species, Cyrtiorina houi n. sp., Goungjunspirifer sinicus F.M. Zhang, and Cyrtospirifer procumbens Simorin in Litvinovich et al., are described. Ulbospirifer? junggarensis and Goungjunspirifer sinicus are characterized by a prismatic layer. Cyrtiorina houi shows a moderately high and triangular ventral interarea, with delthyrium covered by pseudodeltidium with a rounded foramen. Cyrtospirifer procumbens can be distinguished from other species of this genus by its shallow, clearly limited sulcus with prominent primary plications, and high ventral interarea. Cyrtospirifer transversus has an alate to subpentagonal outline. Cyrtospirifer koketekensis has rounded and distinct flank plications. The ventral delthyrium of “Mucrospiriferquadratus is covered by a pseudodeltidium. Tylothyris cf. novamexicana develops an angular sulcus in cross-section. Comparisons with the coeval brachiopod faunas from various regions indicate that, biogeographically, western Junggar has a close relationship with the Tarbagatai Mountain Range, northeastern Kazakhstan, central Kazakhstan, and Karaganda Basin, and a certain affinity with North America.  相似文献   

2.
Trends in generic diversity of successive conodont communities are analysed in sections of different environmental settings across the Frasnian–Famennian (F–F) boundary in the stratotype area, Montagne Noire, France. The evolution of conodont biofacies and abundances matches the overall pattern already observed in many sections elsewhere in the world and supports the interpretation of an important eustatic sea-level fall during the Upper Kellwasser event. The change from late Frasnian deep-water palmatolepid–polygnathid biofacies to shallower-water polygnathid-icriodid biofacies during the Upper Kellwasser event occurred in all sections studied. The shallowing trend culminated at the end of the Kellwasser Event as indicated by the substantial increase of formerly poorly represented icriodids, whereas palmatolepids concomi-tantly diminished. This event occurred earlier on oxygenated outer platform submarine rises than in oxygen-depleted depressions. The sudden sea-level fall prior to the Frasnian–Famennian boundary was followed, at the beginning of the Famennian, by a deepening trend when palmatolepids dominated again. These changes in conodont generic associations and abundances occurred rapidly and synchronously. As a result, the stratigraphic resolution obtained with the evolution of biofacies is higher: it permits not only a more accurate location of the base of the Upper Kellwasser event in environments where it cannot be distinguished lithologically, but it also allows the recognition of intrazonal gaps.  相似文献   

3.
New bryozoans from the Upper Devonian (Famennian) of the borderlands of the Kuznetsk Coal Basin are described: Orthopora tomensis sp. nov. and Minussina incrustata sp. nov.  相似文献   

4.
The gastropod fauna of the Upper Devonian Baggy and Pilton formations in south‐west England is revised and includes some 30 taxa. The topmost part of the Upper Famennian succession in Devon is represented by clastic near‐shore and shallow shelf sediments, indicating a short‐term transgressive phase (‘Strunian Transgression’). The sequence yields a highly diverse fauna dominated by brachiopods and ostracodes, locally supplemented by crinoids, bryozoans, trilobites and molluscs. The taxa ‘Patellostiumbritannicum sp. nov., Angyomphalus (Angyomphalus) junius sp. nov. and Dictyotomaria eurocapillaria sp. nov. are erected; a junior homonym is replaced by Macrochilina? piltonensis nom. nov. The gastropod fauna displays an independent character, where latest Devonian faunal elements overlap with Late Palaeozoic taxa expressing a transition similar to that of the bivalves, brachiopods, echinoderms and corals, without a sharp faunal break at the Devonian/Carboniferous boundary. Apart from the Caenogastropoda, all subclasses of gastropods are represented. Members of the bellerophontoids, pleurotomarioids and loxonematoids are most abundant, followed by murchisonioids, naticimorphs, euomphalomorphs and platyceratoids. The various gastropod groups represent different ecological demands and trophic categories, and together with the accompanying fauna indicate that nearly all habitats and niches were occupied in the shallow South Laurussian Shelf.  相似文献   

5.
《Palaeoworld》2021,30(4):649-658
A recent study of conodonts from the Wuxiahe Formation (lower to middle part) in the Ziyang-Langao region suggested its age of middle Telychian (Llandovery) to lower Sheinwoodian (Wenlock), contradicted by subsequent graptolite studies indicating an age of late Telychian for the same interval. New samples from the Qiaoxi section for conodonts to re-access the age of the Wuxiahe Formation collected in this study show that the lower to middle part of the formation belongs to the Pterospathodus amorphognathoides amorphognathoides Biozone, suggesting the age of late Telychian; thus, the Llandovery–Wenlock boundary in the section is most probably higher than previously estimated, but its precise position is not determined since the identification of the Wenlock graptolite Cyrtograptus cf. lundgreni in the section is to be further confirmed. Based on the conodont faunas recognized in the Qiaoxi and Tianwancun sections, the base of the Wuxiahe Formation in the Ziyang-Langao region is diachronous, i.e., not higher than the upper Telychian Pterospathodus amorphognathoides amorphognathoides Biozone at Qiaoxi, but not lower than the lower Sheinwoodian Kockelella ranuliformis Biozone at the Tianwancun setion.  相似文献   

6.
A new conodont species, Antognathus vjatsheslavi sp. nov., is described from the Famennian shallow-water carbonate deposits of the Bolshoi (Greater) Karatau Range in southern Kazakhstan.  相似文献   

7.
Summary Microbial reefs, together with stromatolitic mounds and ooid shoals, constitute massive limestones in Famennian platform marginal strata in Guilin, in sharp contrast to the well-known coral-stromatoporoid reefs in the Givetian and Frasnian. Microbes played a significant and important role as stabilizers in the Famennian carbonate deposits of Guilin. A reef at Zhaijiang was constructed byEpiphyton andRenalcis, and is representative of such carbonate buildups. The reef is situated 10 km west of Guilin and corresponds to a microbe-dominated platform margin carbonate complex. Organisms in the Zhaijiang microbial reef are low diversity and dominated by ostracods and two genera of microbes,Epiphyton andRenalcis. Other microbial genera such asSphaerocodium andWetheredella occur in most of reef facies in Guilin, but their role as reef builder is doubtful because they occur only in minor amounts. The same four genera occur in volumetrically significant amounts in the upper Devonian carbonate complexes of Alberta. Canada and Western Australia. However.Epiphyton is more abundant in the Guilin reefs. The Zhaijiang microbial reef developed above Famennian proximal slope faices, as suggested by reef architecture and paleogeographic setting. The facies sequence of the microbial reef can be divided into three parts. The lower part is composed of medium-bedded bioclastic grainstones with a few microbial framestone lithoclasts, representing a proximal slope facies. The middle part consists of thin-bedded mudstone and shale with limestone lenses that are thought to be low stand deposits. In some cross sections, mudstone and shale infilled tidal channels that developed in the bioclastic grainstones.Renalcis-Epiphyton framestone constitutes the upper part with massive stacking patterns. The reef is 35 m thick and over 50 m in width. Nine litho- and biofacies are recognized. Zhaijiang reef provides an example of a binder guild-dominated buildup in the almost vacant reef ecosystem of the Famennian and represents a characteristic kind of reef after the Frasnian/Famennian extinction.  相似文献   

8.
鄂西地区中–晚奥陶世之交的庙坡组由数米厚的页岩夹少量薄层灰岩构成,沉积于扬子陆表海区凹陷带中,深度位于最大浪基面下,含有多样性、丰度高的化石组合。宜昌北部的陈家河剖面以及远安真金剖面庙坡组中–上部页岩属晚奥陶世桑比期Nemagraptus gracilis笔石带。笔者在该层位首次采获30余枚海林檎化石,经系统古生物学鉴定均为Cheirocrinus penniger (Eichwald, 1842)。远安真金剖面产出的C. penniger标本多以萼部区数个不同类型压扁的骨板形式保存, 1枚标本保存有完整的茎部;宜昌陈家河剖面的C. penniger标本均以单个萼部骨板形式保存。奥陶纪的Cheirocrinus广泛分布于多个板块,本文描记庙坡组的Cheirocrinus化石记录实例,扩展了该属在华南板块的时空分布,它可以从黔南三都早奥陶世斜坡相的同高组延续到晚奥陶世台内凹陷带的庙坡组。  相似文献   

9.
Immo Schülke  Adrian Popp 《Facies》2005,50(3-4):647-664
High resolutional microfacies data from the Beringhauser Tunnel section in the northern part of the Rheinisches Schiefergebirge allow the reconstruction of a relative sea-level curve. Distinctive sedimentological signals in this cephalopod limestone section indicate the positions of sea-level lowstands that correlate well with pre-existing sea-level curves. Only slight differences in some lowstand positions have been observed by means of conodont biostratigraphy. The basal Famennian portion of the succession at the Beringhauser Tunnel section exposes microbial sedimentary structures reported from the Rheinisches Schiefergebirge for the first time that are indicative of initial mud-mound formation or mud-mound flanks. Further mud-mound growth with the development of a synsedimentary relief was stopped, probably due to drowning.  相似文献   

10.
《Palaeoworld》2021,30(4):659-676
The lower/upper Emsian boundary witnessed prominent diversification of biostratigraphically important genera Polygnathus Hinde, Caudicriodus Bultynck, and Latericriodus Müller. In contrast, conodonts previously reported around this boundary from the South China Block were characterized by relatively low species or subspecies diversity, and only a few widely distributed and extensively studied zone-defining taxa were recorded. In this paper, conodonts from the Daliantang Formation at the Daliantang section (Guangnan, southeastern Yunnan), one of the representative sections of the transitional facies between the benthic Xiangzhou facies and the pelagic Nandan facies, are investigated. The conodont fauna shows a remarkably high species or subspecies diversity, with fourteen taxa that are assignable to the notoperbonus Zone and inversus Zone. Five polygnathid species are described: P. gronbergi Klapper and Jonson, P. inversus Klapper and Jonson, Polygnathus sp. B, P. luciae Martínez-Pérez and Valenzuela-Ríos, and P. mashkovae Bardashev. The latter two are reported for the first time from the South China Block. Additionally, three icriodontid taxa are also described, of which L. guangnanensis n. sp. is characterized by distinctly chevron-shaped transverse rows in the anterior part and a well-developed process branching off to the outer side. The new conodont record increases our understanding of the diversification and faunal composition around the lower/upper Emsian boundary in the South China Block. It contributes to the regional and inter-regional biostratigraphical correlation between shallower- and deeper-water facies and also furnishes important South China material for future discussion and deliberation on the position of the lower/upper Emsian boundary.  相似文献   

11.
12.
New Lower-Middle Frasnian conodonts of the genus Palmatolepis Ulrich et Bassler, 1926 are described from the Kalagach and Kulyali formations of the Sishkat key section of Central Tajikistan. Palmatolepis manzuri sp. nov. descends from Pa. punctata (Hinde) and is an ancestor of Pa. kireevae Ovnatanova, Pa. salibaevi sp. nov., and also of the Pa. rhenana Bischoff branch.  相似文献   

13.
准噶尔盆地中侏罗世晚期到晚侏罗世早期沉积的石树沟组产出过包括多种兽脚类恐龙在内的大量脊椎动物化石。描述了一件新的采自准噶尔盆地东北缘五彩湾地区石树沟组上部的兽脚类恐龙左第四跖骨标本(IVPPV18060)。通过与其他兽脚类恐龙第四跖骨对比,该标本可归入异特龙超科(Allosauroidea)。它与其他异特龙超科第四跖骨的相似性包括:近端关节面三角形并有一向后方延伸的舌状突出,向外侧轻微弯曲的骨干,位于骨干后方靠近外侧边的半月形肌肉凹陷,三角形骨干横截面。在异特龙超科当中,V18060与准噶尔盆地将军庙地区石树沟组中发现的董氏中华盗龙(Sinraptordongi)最为相似(除了以上相似性,V18060和董氏中华盗龙的相似性还包括远端关节轮廓呈近梯形,骨干后部肌肉凹陷与周围边界呈半开放状态)。但是,V18060和董氏中华盗龙也存在着一些明显的区别:V18060明显比董氏中华盗龙的第四跖骨粗壮,远端内外两髁大小差异相反。这些形态差异可能是由于个体发育或者性双形造成的,也可能代表分类学差异。对比研究和基于第四跖骨形态信息进行的分支系统学分析结果更偏向后一种解释:V18060代表一个不同于董氏中华盗龙但与后者亲缘关系很近的新的兽脚类恐龙。新材料的发现增加了中晚侏罗世石树沟动物群兽脚类恐龙的分异度。在五彩湾和将军庙地区发现不同的中华盗龙类恐龙指示了晚侏罗世早期准噶尔盆地中相邻地区可能存在着一定的生态分异性或者地理隔离。  相似文献   

14.
A new eucryptodiran turtle, Xinjiangchelys qiguensis sp. nov. from the Upper Jurassic (Oxfordian — ?Kimmeridgian) Qigu Formation of the southern Junggar Basin (north‐west China) is described. The type material consists of a partial skeleton, including the complete carapace, plastron, nearly all cervical vertebrae, both scapulae, the pelvis and one ulna. It is clearly identifiable as a basal eucryptodire since it lacks the mesoplastron. It is distinguished from other species of Xinjiangchelys by several autapomorphies of the carapace and plastron, such as the first and fifth vertebrals extending on the peripherals, the plastron with three pairs of gulars, and an intergular which does not contact the hyoplastron. In the postcranium, the scapula with a long acromial and a small scapular process, the pelvis with a short ilial shaft and the elongated cervical vertebrae are characteristic. A new phylogenetic analysis of the in‐group phylogeny of the Xinjiangchelyidae is proposed and discussed, resulting in a new classification of the family. Xinjiangchelys (Toxocheloides) narynensis is regarded as a nomen dubium. Shartegemys is referred to Xinjiangchelys, whereas the holotypes of ‘Plesiochelyschungkingensis and ‘P’. latimarginalis are excluded from the genus Xinjiangchelys but included in the Xinjiangchelyidae.  相似文献   

15.
The Anjihaihe Formation in the southern edge of the Junggar Basin was previously considered a series of freshwater lacustrine depositions. However, abundant marine dinoflagellate cysts were recently recovered from the middle to upper part of the middle member of the formation. Two new genera, six new species and one new subspecies among the abundant dinoflagellate cysts are described and illustrated, i.e. Circulodinium? laeve sp. nov., Kaiwaradinium abbreviatum sp. nov., Spiniferites adnatus subsp. latispinus subsp. nov., Oligosphaeropsis accreta gen. et. sp. nov., Oligosphaeropsis complex gen. et. sp. nov., Oligosphaeropsis megaprocessa gen. et. sp. nov. and Tianshandinium biconicum gen. et. sp. nov. They are rare to common constituents of the dinoflagellate assemblage in the Anjihaihe Formation and may prove useful for regional biostratigraphic correlation and palaeoenvironment re-establishment.  相似文献   

16.
Remains of two large sarcopterygians are described from Famennian deposits in Belgium. One of them is referred to Eusthenodon wängsjöi Jarvik; it is the first occurrence of this genus in Belgium. The other, much larger one, appears to be a tristichopterid. It has a postspiracular; size and shape of the mandible similar to those of Platycephalichthys skuenicus and P. bischoffi ; snout and cheek patterns close to those of Eusthenodon ; unusual shape of the supratemporal resembling that of Hyneria , Mandageria and Platycephalichthys skuenicus ; and tooth histology quite similar to that of Eusthenodon and Platycephalichthys .  相似文献   

17.
Representatives of nine bryozoan genera of four orders are identified for the first time from the carbonate deposits of the stratotype section of the Upper Kazanian Substage of the Middle Permian. Among them four new species are established and described: Permopora volgensis sp. nov., Stellahexaformis burovi sp. nov., Alternifenestella esaulovae sp. nov., and Wjatkella definita sp. nov. A brief lithological characterization is provided of the carbonate deposits that contain the remains of these bryozoans and were formed under the conditions of transgression-regression cycles of the Late Kazanian marine basin. Some questions concerning the taphonomy, ecology, and morphology of the bryozoans studied are considered.  相似文献   

18.
The first evidence of an ankylosaur from the Late Jurassic Qigu Formation of the southern Junggar Basin (Xinjiang, northwestern China) is described, based on an isolated caudal vertebra that was discovered together with fragmentary remains of other dinosaurs, including stegosaurs, sauropods, and theropods. The caudal vertebra is characterized by the following features: (i) elliptical morphology of the centrum, being wider than high; (ii) short antero-posterior length of the centrum; (iii) pronounced transversely extending ventral groove; (iv) massive transverse process, that is longer than the centrum diameter; (v) transverse process meeting the centrum high at the dorsal half and at a relatively flat angle; (vi) transverse process making a broad contact with the neural arch without forming a proximo-dorsal projection; and (vii) notochordal prominence present in the centre of the anterior articular surface. The study specimen represents only the second record of an ankylosaur from the Jurassic of Asia — aside from the slightly older Tianchisaurus from the early Upper Jurassic Toutunhe Formation, equally from the Junggar Basin. It helps to fill a gap in our knowledge of the early evolution of these armoured dinosaurs. Additionally, this discovery highlights the potential of the southern Junggar Basin to yield a rich vertebrate fauna and thus to provide an important insight into Late Jurassic ecosystems of Central Asia.  相似文献   

19.
20.
《Palaeoworld》2015,24(3):263-276
This paper documents smaller foraminifers from the Maokou Formation (Guadalupian) at the Tieqiao section in Laibin area, South China. The assemblage of smaller foraminifers reported herein consists of 69 species of 42 genera. Although the Maokou Formation of this section was deposited in a relatively deep-water environment, smaller foraminifers are diverse and abundant, especially in debris flow deposits and thin turbidite beds. This fauna bears most similarity with coeval foraminiferal assemblages from the other Palaeotethyan regions. There is a sharp decrease in the diversity and abundance of smaller foraminifers at the lithological boundary between the Maokou and Heshan formations. An overwhelming majority of genera of smaller foraminifers that occur in the Maokou Formation at this section can be found in the Lopingian strata of South China. The study of smaller foraminiferal fauna of the Guadalupian at the Tieqiao section indicates a much less pronounced effect of the pre-Lopingian crisis on smaller foraminifers.  相似文献   

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