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1.
Seven brachiopod species (including three new species) and three undetermined forms are described and figured here from an unnamed stratigraphic unit which mainly consists of argillaceous and bioclastic limestone near the stratotype of the Late Silurian Xibiehe Formation of the Xibiehe section in the Darhan Mumingan Joint Banner, north of the Bateaobao area, Inner Mongolia. Three new species, Eoschizophoria minuta, Navispira navicula and Howellella asiatica are established with transverse serial sections for their interiors. All brachiopod taxa described here show that this unnamed stratigraphic unit is higher than the Late Silurian Xibiehe Formation in the Xibiehe section and is possibly transitional between the Late Silurian and the Early Devonian. Authors temporarily regard this unit as the upper part of the Xibiehe Formation in this paper.  相似文献   

2.
New brachiopods of the suborder Delthyridina Ivanova (order Spiriferida) from the Lower and Middle Devonian of northeastern Russia, Ivanothyris costatus sp. nov. (subfamily Delthyridinae), Eoreticularia lata sp. nov., Yania gen. nov. with the type species Y. tumida sp. nov. (subfamily Eoreticulariinae), Reticulariopsis equitans Modzalevskaya, and R. (?) borealis sp. nov. (subfamily Reticulariopsinae) are described.  相似文献   

3.
Two new species, Paramesosciophilodes bellus sp. n. and Paramesosciophilodes rarissima sp. n., from the Jiulongshan Formation at Daohugou Village, Inner Mongolia, China, are described in the extinct family Mesosciophilidae. Altogether seven genera with 21 species of mesosciophilids have been described from the Jurassic of Siberia and Kazakhstan, the Lower Cretaceous of Transbaikalia, and the Middle Jurassic of Inner Mongolia. An emended generic diagnosis of Paramesosciophilodes and a list of known taxa of mesosciophilids are provided.  相似文献   

4.
Eight new species of Ostreioceratidae are described from the Lower and Upper Devonian of Novaya Zemlya, Lower Devonian of the Pechora River basin, North Ural Mountains, and the Zeravshan Range: Ostreioceras admotum, O. simile, O. abruptum, O. sobolevi, Plagiostomoceras kuzmini, P. adumbratum, P.? acerbum, and P. vinogradovi. A new family Bogoslovskyidae is established in the order Palliocerida.  相似文献   

5.
Two new species of fossil snipe flies (Rhagionidae) from the Daohugou Formation of Chifeng City in Inner Mongolia Autonomous Region (northeastern China) are described as Palaeoarthroteles jurassicus nov. sp. and P. pallidius nov. sp. They are the first record of the genus Palaeoarthroteles Kovalev and Mostovski beyond Siberia, which have implications for stratigraphic correlation of the formations in which they are found.  相似文献   

6.
Michel Melou 《Geobios》1981,14(1):69-87
Three species of Isorthidae are described in the Lower Devonian of the Armorican Massif. Two of them were hitherto badly known, being never adequately described nor figured: Isorthis (Protocortezorthis) miloni from the Gahard Formation (Gedinnian) and Isorthis (Protocortezorthis) trigeri from the Saint-Céneré Formation (Gedinnian-Siegenian). Isorthis oehlertiSolle, 1976 is considered as a synonym of Isorthis (Protocortezorthis) trigeri. The geographic distribution of these species allows to corroborate that until the top of the Lower Devonian (top of Le Faou Formation), two provinces with different faunal associations exist in the Armorican Massif.  相似文献   

7.
《Palaeoworld》2022,31(3):419-427
A new species Paraconularia abagaensis n. sp. is established, based on newly discovered conulariid fossils collected in Abaga Banner, Inner Mongolia, China. The periderm of the new species is characterized by equal faces, 12–26 transverse ribs per cm with nodes numbering from 4–6 per mm, adapertural spines in the interspaces, alternated ribs along the midline, and apical angle ranging approximately from 14° to 18°. The most similar species, P. salinensis, differs from P. abagaensis n. sp. in having a periderm with a significantly larger apical angle and a lower density of nodes. Co-occurring fossils (i.e., brachiopods, gastropods, bivalves, and plants) and U–Pb dates obtained in situ from detrital zircons suggest that the analyzed conulariid-bearing strata are Permian in age. Our study suggests that species previously established merely based on internal mold specimens may need further examination. The diagnosis of Paraconularia was revised and in the genus we identified three morphotypes, based on which we suggest that species whose midlines present ridges or grooves, and whose transverse ribs do not abruptly bend adaperturally at the edges of the corner grooves, be excluded from the genus Paraconularia.  相似文献   

8.
《Palaeoworld》2016,25(4):639-646
Additional specimens of rhynchonellide brachiopods from the marly limestones in the Yidade Formation at the Panxi section in eastern Yunnan have been ascribed to the species “Paurorhynchasquamosa Wang, 1956 and “P.depressa Wang, 1956. The two species have been used frequently as index fossils for the Frasnian (Upper Devonian), but their taxonomic assignments are problematic because their internal structures remain unknown. In this study, detailed systematical examinations on both external characters and internal structures revealed by serial sections suggest that the two species are more appropriately assigned to the genus Hadrotatorhynchus Sartenaer, 1986. Based on the stratigraphical distributions of Hadrotatorhynchus and the conodonts in the upper unit of the Yidade Formation, the Hadrotatorhynchus-bearing horizons are re-considered as the uppermost Givetian (Middle Devonian) rather than Frasnian stage, although the precise position of the Middle/Upper Devonian boundary still depends on further investigations of high-resolution biostratigraphy.  相似文献   

9.
This paper presents a review and critical analysis of the literature on Devonian floras of the Iberian Peninsula. Although the known outcrops of Devonian strata in the Iberian Peninsula are marine, in some cases, a few fragmentary remains of vascular plants are associated with faunal remains. Records include largely specimens from the Lower Devonian of Barrancos (Alentejo, Portugal) and the Upper Devonian of Sierra de Hornachos in Badajoz province, southwest Spain; the remainder consists of drifted plant fragments from scattered sites in the Iberian Peninsula ranging in age from Lochkovian to Upper Devonian-Earliest Carboniferous. The vegetation inferred for the Lower Devonian of the Iberian Peninsula is mainly based on palynological data and corresponds to herbaceous types characterised by bryophytes, rhyniophytes (Horneophyton, Cooksonia, Rhynia), trimerophytes (Psilophyton, Pertica and Hostinella), primitive lycophytes (Drepanophycus) and incertae sedis such as Nothia and Chaleuria, all flora that developed near the coast in low-lying and, at least periodically, wet areas. In the Middle Devonian, two vegetation strata can be recognised: herbaceous (Psilophyton) and semi-arboreal (Cladoxylales). Although three levels of vegetation in the Upper Devonian, have been described from outcrops worldwide, the scarce available data from the Iberian Peninsula only indicate an arborescent lycopsid vegetation and species with uncertain botanical affinity such as Sphenopteridium keilhauii Nathorst.  相似文献   

10.
New spiriferids (Brachiopoda) are described from the Lower and Middle Devonian of northeastern Russia: Tatjanaspirifer iskrensis sp. nov. and T. magnificus sp. nov. (family Reticulariidae); Cyrtina inveterata Baranov, sp. nov. and Blodgettospirifer gen. nov. with type species B. lezhoevi sp. nov. (family Cyrtinidae).  相似文献   

11.
New Lower Devonian brachiopod taxa of the family Reticulariidae (order Spiriferida) are described from northeastern Russia: Havlicekospirifer gen. nov. with the type species H. mirabilis sp. nov. (subfamily Reticulariinae) and Pavlovispirifer gen. nov. with the type species P. pelagicus sp. nov. (subfamily Rhenothyridinae).  相似文献   

12.
云南省昭通市东北郊箐门出露了一条比较完整的泥盆系浅海相地层剖面,下、中、上三个统均有出露,浅海底栖生物化石丰富,研究基础也相对较好,是研究滇东北地区泥盆纪地层的一条理想剖面。由于地层剖面比较长,沉积厚度比较大,此前我们已经描述了早泥盆世和中泥盆世早期的四射珊瑚,本文继续描述该剖面的中泥盆世晚期的地层及其四射珊瑚,讨论它们的地层划分、珊瑚群对比与古生物地理。至于晚泥盆世的珊瑚,由于篇幅的关系,我们拟另文继续描述。  相似文献   

13.
14.
Lower Devonian strata from the drill cores from Poland have yielded new Heterostraci material. One ventral shield of Toombsaspis (Traquairaspididae, Phialaspidinae) discovered in the Białopole IG-1 drill core, and a fragment of dorsal shield of cf. Paraliliaspis (Cyathaspididae, Anglaspidinae) with the impressions of internal structures from Ciepielów IG-1 are described and provide new information on paleogeographic disparity of these groups.  相似文献   

15.
Pentamerids (Brachiopoda) are described from the Lower and Middle Devonian of northeastern Asia: Antirhynchonella cherkesovae sp. nov. belonging to the family Clorindidae and Devonogypa indigirica (Sidjachenko), Vadimia gen. nov. with the type species V. gonensis sp. nov. and V. naanchanensis sp. nov., and Vladimiria gen. nov. with the type species Vl. yanensis sp. nov. all belonging to the subfamily Devonogypinae.  相似文献   

16.
The morphological variability of the genus Navifusa Combaz et al. 1967 ex Eisenack 1976 has been investigated within three populations from a Lower Devonian section at Císa?ská rokle, near Srbsko (Barrandian area, Czech Republic). All observed specimens can be attributed to the single species Navifusa bacilla. Differences in size ratio are interpreted ecologically, initiated by sea level changes. The method of cyst opening of this species is discussed, as it allows recognition of different phases of excystment.  相似文献   

17.
The stratigraphic levels most favoured for the Middle-Upper Devonian boundary fall approximately within the range of the ammonoid Pharciceras lunulicosta Zone, i.e. from the Middle varcus Subzone to the base of the Lower asymmetricus Zone of the conodont scale. Spore data that are potentially useful for recognition of the boundary within this range have been correlated with conodont zones in marine facies in the Boulonnais region of France. A vast amount of information on spores from Middle-Upper Devonian boundary strata has accumulated in the European U.S.S.R., where the boundary is taken at a somewhat lower level. Late Givetian and early Frasnian continental strata of Melville Island in the Canadian Arctic contain species present in the Boulonnais or the European U.S.S.R., as well as species common to both regions. Diatomozonotriletes spp., Rhabdosporites langii, Samarisporites triangulatus, Contagisporites optivus, Archaeoperisaccus timanicus, Chelinospora concinna and Ancyrospora langii, among others, may be useful for correlating the boundary as eventually defined. The stratigraphic ranges of most of these taxa show only limited agreement interregionally at present, probably owing at least in part to problems of spore nomenclature and taxonomy, and an insufficiency of spore reference sequences keyed to faunal zones. Nevertheless, individual species of spores, and especially assemblages of species, have much potential for delimiting and correlating the Middle-Upper Devonian boundary in both marine and continental facies.  相似文献   

18.
Gobiatherium Osborn &; Granger 1932 is a highly distinctive genus of dinoceratan known from Eocene strata in Kyrgyzstan, Kazakstan, and Nei Mongol and Henan, People’s Republic of China. Autapomorphies ofGobiatherium among uintatheriids are: skull long, narrow and shallow with a flat sagittal region; nasals strongly arched with bony septum connecting their anterior ends to the premaxillae; zygomatic arches broad and flare outward in region of glenoid fossae; lower jaw long and shallow with tall ascending ramus and without an inframandibular flange; no upper canines; lower canines greatly reduced; P2 has prominent cingular cusp on its anterolabial corner; metacarpals relatively long and slender. Two species ofGobiatherium are valid, the type speciesG. mirificum Osborn &; Granger 1932 (=G.? major Qi 1987) and the much smaller and poorly knownG. minutum Cheng &; Ma 1990. G.?monolobotum Qi 1987 is a junior subjective synonym of the coryphodontid pantodontEudinoceras mongoliensis Osborn 1924. The distribution ofGobiatherium supports recognition of an Arshantan land-mammal ‘age’ (LMA) older than the Irdinmanhan LMA. The Arshantan LMA is redefined as the time interval between the first appearance datum (FAD) of the coryphodontid pantodontEudinoceras and the FAD of the brontotheriid perissodactylProtitan. Gobiatherium is one of several index taxa that allow mammalian assemblages of Arshantan age to be identified in China, Mongolia, Kazakstan and Kyrgyzstan.  相似文献   

19.
A new taxon of ginkgophyte affinity Palaeoginkgoxylon zhoui gen. nov. et sp. nov. is described from the Guadalupian Lower Shihhotse Formation of the Hulstai coalfield, Inner Mongolia Autonomous Region (Nei Mongol), northern China, on the basis of the anatomical structures of the broad eustele and pycnoxylic secondary xylem. The anatomical structure of the new woody tree trunk resembles both the early gymnosperms of Eristophyton-Pitus types and the modern Ginkgo. Therefore, the new tree trunk is interpreted as representing a transitional stage in the evolution of Ginkgo from early arborescent lignophytes since the Early Carboniferous.  相似文献   

20.
A new linoproductid genus is described from the provincial Terrakea arguta Zone (lower part of the Upper Kazanian Substage) of the key section of the Tsagan-Temete Horizon (Kazanian Stage-Lower Tatarian Substage) of northeastern Mongolia. The type species of the new genus was found in the middle layers of the Lower Uldza Subformation, which contains numerous diverse productids from the genus Terrakea.  相似文献   

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