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1.
Jurassic and Cretaceous radiolarian faunas were discovered in bedded chert of the Dinaric and Vardar tectonic zones of Bosnia and Herzegovina. Only Triassic radiolarians have previously been described in Bosnia and Herzegovina, while the finds of Bajocian, Bathonian-Callovian, Oxfordian-Kimmeridgian, Tithonian-Berriasian, and Campanian are new. Additional localities of Triassic and Jurassic radiolarians were investigated in Serbia. By correlation with radiolarians from the previous studies within Serbia, the Late Aalenian-Bajocian and Bathonian-Callovian Serbian radiolarian beds are newly dated. The first find of Cretaceous radiolarians in Serbia is reported. The oldest Mesozoic Radiolaria-bearing formations outcropping in the Western Belt of the Vardar Zone are dated Mid-Upper Triassic. The youngest radiolarians come from the Upper Cretaceous (Campanian) of the northern part of this belt of the Vardar Zone, where they co-occur with planktonic foraminifers. The distribution of 70 radiolarian samples within sections is shown. The taxonomic composition of 39 samples is analyzed. Radiolarian species extracted from 13 samples are described and figured. The list of 72 taxa and 3 plates of Jurassic radiolarians of Bosnia and Herzegovina, 3 plates of Triassic, 1 plate of Middle Jurassic, and 1 plate of Upper Cretaceous radiolarians of Serbia are presented.  相似文献   

2.
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   

3.
This paper continues a former study (Rev. Española Micropaleontol. 14 (1982b) 401), where the author described spicular nassellarian and entactinarian Radiolaria found in the Middle Triassic samples available at that time. Based on the study of new samples bearing well preserved radiolarians collected during the 20 years that followed the former publication, samples coming from Triassic, Jurassic, Cretaceous, and Paleogene deposits, the author found that spicular Nassellaria are extremely rare in the post-Fassanian radiolarian faunas. Their fossil record is punctuated, their occurrences being separated by very long gaps. And even so, when they occur their number is usually reduced to one, two, or several specimens of a single species. Spicular Nassellaria are rare or very rare in the upper Spathian and Anisian, frequent in the upper Anisian-lower Ladinian, practically absent in the upper Ladinian and the whole upper Triassic and pre-Toarcian Lower Jurassic, rare in lower Toarcian, very rare in the Bajocian, rare in the lower Tithonian. No specimens were recorded in the other stages of the middle and upper Jurassic and in the whole Cretaceous, except for one in the Coniacian. In the Paleogene only five species belonging to four genera have been recorded in the upper Paleocene-middle Eocene. In the Neogene the only genus known so far is Neosemantis that occurs sporadically since the lower Miocene. A wider diversity is recorded in the living plankton or Recent sediments that comprise all genera and species described in the literature before 1970. It is suggested that this scarcity reflects their real scarcity in the tropical or subtropical seas of the past, but this scarcity was probably magnified by selective preservation. The idea of origination of spicular Nassellaria once or several times from shell-bearing Nassellaria by the reduction of shell during some environmental crises of the Mesozoic and Cenozoic or by hybridization is rejected because the group is rather unitary in its spicular structure and it shows a certain evolution from taxa with massive spines to taxa with three-bladed spines. Nassellarian-like spicular Radiolaria range within the boundaries of the Triassic; they seem to have disappeared by the end on the Norian.In order to give a complete inventory of these radiolarians all taxa known in the Mesozoic and lower Cenozoic are described, discussed, or just mentioned. They comprise 44 species of which 20 are new, 14 genera of which six are new (Palaeosemantis, Molzaxis, Daniplagia, Verticiplagia, Jeanpierria and Nandartia), three subfamilies of which one (Zaldacriinae) is new, and two families (Plagiacanthidae and Archaeosemantidae).  相似文献   

4.
New caddisflies, reculid and eoblattid insects from the Mesozoic of Asia are described. Caddisflies of the families Philopotamidae (Mesoviatrix paradoxa gen. et sp. nov. and Kempia piotri gen. et sp. nov.) and Polycentropodidae (Polylongevus eskovi gen. et sp. nov.) from the Upper Jurassic–Lower Cretaceous of the Kempendyai locality in Yakutia are described. A short review and comparison of fossil members in these families are provided. New Gryllones insects, Shurabia tanga sp. nov., Sauk batkenicus gen. et sp. nov. from the Sauk Tan’ga locality (Lower Jurassic of Kyrgyzstan), Say kirgizicus gen. et sp. nov. from the Shurab III locality (Reculida: Geinitziidae; Lower or Middle Jurassic of Kyrgyzstan) Griphopteron iya sp. nov. (Eoblattida: Blattogryllidae) from Iya locality (Middle Jurassic of Russia) are described.  相似文献   

5.
The trend of species diversity and spatiotemporal distribution of spherical radiolarians of the genus Entactinia Foreman, 1963 in the Permian Period is analyzed. The center of origin of Permian entactinians in the Cis-Ural Paleobasin is established in the area of the modern interfluve of the Ural River and latitudinal current of the Belaya River on the Southern Urals. It is shown that the species composition of this genus almost completely changed in certain Permian epochs. Two forefather species of each new pleiad of Early, Middle, and Late Permian are revealed: Entactinia parapycnoclada and E. tyrrelli. Two new species of the Lower Permian radiolarians from the Southern Urals and Northern Mugodzhary, E. chernykhi sp. nov. and E. subquadrata sp. nov., are described.  相似文献   

6.
The first radiolarians discovered in the Ordovician of the Argentinian Precordillera are reported. The material is associated with conodonts indicating the upper part of the Lenodus variabilis Biozone (Lower Darriwilian, Da1-2). The low diversity radiolarian fauna shows similarities with Middle Ordovician radiolarians from the Akzhal Mountains of Kazakhstan. However, a close comparison is difficult due to the poor preservation of the material, in which internal structures of the radiolarian tests are not preserved.  相似文献   

7.
Relatively well-preserved polycystine Radiolaria are here described from Lower Cambrian (Botomian) strata of the Shashkunar Formation, Altai Mountains in southern Siberia (Russia). These radiolarians display a test formed of a disorderly and three-dimensionally interwoven meshwork of numerous straight and curved bars branching from a five-rayed point-centered spicule located within the inner shell surface. The shell structure allows their assignment to the family Archeoentactiniidae, thus extending the known age range of the family down to the Lower Cambrian. The Botomian age is based essentially on trilobites (Parapagetia-Serrodiscus zone), but also on archaeocyathids identified in earlier publications. The study of the radiolarian-bearing sedimentary sequence confirms the presence of polycystine radiolaria in the external platform environments of Lower Cambrian ecosystems.  相似文献   

8.
Late Emsian-Early Eifelian radiolarians from the southern Ural Mountains are recorded and described for the first time. They come from the Kamennaya Gora section on the Tanalyk River near the town of Buribay, Bashkiria. The new Late Emsian-Early Eifelian radiolarian assemblage consists of 20 species of 11 genera of spherical, discoidal, spindle-shaped, pylomate, and spiny radiolarians. Four new species, i.e., Entactinia rostriformis sp. nov., Palaeodiscaleksus tumefactus sp. nov., Primaritripus buribayensis sp. nov., and P. chuvashovi sp. nov., are described. The diagnosis of the genus Primaritripus Afanasieva, 2000 is amended. The fact that the oryctocenosis is dominated by discoidal radiolarians suggests that, in the Late Emsian-Early Eifelian, the area under study was occupied by a relatively shallow marine basin. Based on radiolarians, a new Upper Emsian-Lower Eifelian biostraton, beds with Primaritripus buribayensis-Entactinia rostriformis, is established. The history of the study of Early Devonian radiolarians is considered.  相似文献   

9.
Podocarpophyllum Gomolitzky is studied in detail from the type locality Angren (Uzbekistan, Middle Jurassic). Emended diagnoses of the genus and its type species P. singulare Gomolitzky are provided. For the first time, members of the genus are reported from the Lower Jurassic of the Mangyshlak Peninsula (western Kazakhstan), where P. kazachstanicum sp. nov. is described, and from the Middle Jurassic of the eastern Ural Mountains, where P. mesozoicum (Kiritchkova) comb. nov. is established. The epidermal morphology of the genus Podocarpophyllum is compared with that of fossil and modern members of the Podocarpaceae.  相似文献   

10.
Two new species, Mirovia asiatica sp. nov. and Mirovia kazachstanica sp. nov., are described from the Lower Jurassic of Mangyshlak (western Kazakhstan). Representatives of Mirovia Reymanówna are for the first time found in the Lower Jurassic and for the first time in Central Asia. A new combination, M. eximia (Gordenko), comb. nov., is proposed. The morphology of stomatal guard cells is described in detail, based on examination of cross sections of leaves.  相似文献   

11.
In the present paper, we discuss the evolution of an upper Permian anagenetic lineage of polycystine radiolarians belonging to the genus Albaillella. This genus is characterized by increasing curvature of the shell during the upper Permian and the trend is reversed (proteromorphic retrogradation) in the Lower Triassic with the sudden appearance of forms that are homeomorphic to the earliest Permian representative of the genus. These primitive-looking forms are derived from their immediate ancestors by retrograde evolution, a phenomenon which has been described as proteromorphosis.  相似文献   

12.
A new specimen of the widespread Middle Jurassic to Lower Cretaceous Asian gonipholidid crocodilian genus Sunosuchus is described on the basis of a partial skeleton from the Upper Toutunhe Formation (Middle Jurassic, ?Bathonian-Callovian) of Liuhonggou, SW of Urumqi, Xinjiang Uygur Autonomous Region, People’s Republic of China. The specimen is represented by a partial mandible, teeth, vertebrae, limb and girdle bones and osteoderms. It can be distinguished from other nominal species of the genus by a unique combination of characters: slightly heterodontous dentition, strongly sculptured posteroventral part of the mandible, short fenestra mandibularis, convex dorsal surface of the retroarticular process, keeled cervical vertebral centra and ventral osteoderms with a distinctive sculpture of wide pits and narrow ridges. The heterodontous dentition is a potential autapomorphy of this form. The new specimen is closest in morphology to material described recently from the Callovian of Kirghisia as Sunosuchus sp. It represents the second Middle Jurassic record of the genus, the first crocodile from the Toutunhe Formation, the first substantial crocodile find from the Mesozoic of the Southern Junggar Basin, and the first Middle Jurassic record of Sunosuchus from China. This extends both the paleobiogeographical distribution of the genus in Asia and its stratigraphic distribution in China considerably.  相似文献   

13.
Hymenopterans Xyelula alexandri Rasnitsyn, sp. nov. (Sepulcidae) and Kotaphialtites frankmortoni Rasnitsyn, gen. et sp. nov. (Ephialtitidae) are described from the Lower or Middle Jurassic Kota Formation, Andhra Pradesh, India. These finds prove a considerable similarity between the Gondwanan and Laurasian hymenopteran faunas during the Jurassic, as well as during the Triassic and Cretaceous.  相似文献   

14.
Well-preserved Cretaceous (Albian–Turonian) radiolarians were extracted from radiolarian-bearing chert olistoliths of the Monagroulli Member within the Moni Mélange (Campanian-Maastrichtian, Southern Cyprus). Four assemblages were distinguished: Middle Albian–Lower Cenomanian (Thanarla spoletoensis Zone), Upper Albian–Lower Cenomanian (Thanarla spoletoensis Zone, Dorypyle? anisa Subzone), lowermost Turonian (base of Alievium superbum Zone) and Lower Turonian (Alievium superbum Zone). The radiolarian assemblages are diverse and have taxonomic composition similar to coeval assemblages of Italy and Spain. The sediments of the Monagroulli Member differ from coeval rocks of the Mamonia Complex (western Cyprus) by the more common presence of radiolarian cherts and may have been formed in the distal part of a continental margin with less input of clastic material. A new spicular radiolarian genus Cyprothamnus with 2 new species (C. multifurcatus and C. moniensis) is described from the Lower Turonian strata.  相似文献   

15.
The fossil history of the family Geinitziidae is reviewed. New taxa are described in the family: Shurabia hissarica, sp. nov. (Lower Jurassic of Tajikistan), Sh. shartegica, sp. nov. (Upper Jurassic of Mongolia), Sh. serrata, sp. nov. and Ginitzia sagulensis, sp. nov. (both Lower Jurassic of Kyrgyzstan). The subfamily Stegopterinae Sharov, 1961 is synonymized under Geinitziinae Handlirsch, 1906. The genera Minesedes Fujiyama, 1973 and Ominea Fujiyama, 1973 (Upper Triassic of Japan) are synonymized under Shurabia Martynov, 1937 and Geinitzia Handlirsch, 1906, respectively. Geinitzia varia Bode, 1953 (Lower Jurassic of Germany) and Fletchizia picturata Riek, 1976 (Upper Triassic of South Africa) are redescribed from their holotypes. F. kapokraalensis Wappler, 2001 and F. aleda Wappler, 2001 (both Upper Triassic of South Africa) are transferred to the genus Shurabia.  相似文献   

16.
Three new species of the Middle Jurassic stenolaemate bryozoans of the genera Reptomultisparsa d’Orbigny and Microeciella Taylor et Sequeiros are described: R. saratovensis sp. nov. and M. seltseri sp. nov. from the Lower Bathonian and the Upper Callovian of the Saratov Region, respectively, and R. stupachenkoi sp. nov. from the Middle Callovian of the Moscow Region. Some specific features of their astogeny and colonial morphology are discussed.  相似文献   

17.
The following new taxa of the family Phryganeidae are described: Proagrypnia sinitsae gen. et sp. nov. from the Upper Jurassic or Lower Cretaceous of Russia (Chernovskie Kopi locality) and Baissophryganoides popovi sp. nov. from the Lower Cretaceous of Mongolia (Anda-Khuduk locality). A larval case of Folindusia (Acrindusia) phryganoides sp. nov. from the Paleocene of Russia (Arkhara–Boguchan brown coal field) is described. A worldwide overview of the records of fossil adult insects and larval cases of Phryganeidae is presented.  相似文献   

18.
Two ammonites belonging to the genusPictonia Bayle, 1878 (subgenusPachypictonia Schneid, 1940) are described from the Lower Kimmeridgian of the Subbetic of Western Andalusia, this being the first evidence of the presence of this genus in the Mediterranean (Tethydian) Upper Jurassic.  相似文献   

19.

Background

The Middle Jurassic was a critical time in the evolutionary history of ichthyosaurs. During this time interval, the diverse, well-studied faunas of the Lower Jurassic were entirely replaced by ophthalmosaurids, a new group that arose sometime prior to the Aalenian-Bajocian boundary and by the latest middle Jurassic comprised the only surviving group of ichthyosaurs. Thus, the Middle Jurassic Aalenian-Bathonian interval (176–165 million years ago) comprises the time frame during which ophthalmosaurids not only originated but also achieved taxonomic dominance. However, diagnostic ichthyosaur remains have been described previously from only a single locality from this interval, from the Bajocian of Argentina.

Methodology/Principal Findings

In this paper, we describe a new species of ichthyosaur based on a partial articulated specimen from the Middle Jurassic of southwestern Germany. This specimen was recovered from the Opalinuston Formation (early Aalenian) and is referable to Stenopterygius aaleniensis sp. nov. reflecting features of the skull and forefin. The genus Stenopterygius is diverse and abundant in the Lower Jurassic of Europe, but its presence has not previously been confirmed in younger (Middle Jurassic) rocks from the northern hemisphere.

Conclusions/Significance

This specimen represents the only diagnostic ichthyosaur remains reported from the Aalenian. It bears numerous similarities in size and in morphology to the Lower Jurassic species of the genus Stenopterygius and provides additional evidence that the major ecological changes hypothesized to have occurred at the end of the Toarcian took place sometime after this point and most likely did not occur suddenly. There is currently no evidence for the presence of ophthalmosaurids in the northern hemisphere during the Aalenian-Bathonian interval.  相似文献   

20.
Additional material of Todites (Osmundaceae) from the Lower Jurassic Xiangshan Group in Jiangsu and Anhui Provinces, Eastern China is investigated. Five species of Todites are described based on collections (including sterile and fertile pinnae) from eight localities along the Yangtze River, including Todites denticulatus (Brongniart) Krasser, Todites cf. goeppertianus (Muenster) Krasser, Todites nanjingensis sp. nov., Todites princeps (Presl) Gothan and Todites sp. Material of T. denticulatus and T. nanjingensis sp. nov. contains further data of the fertile pinnae. The stratigraphical ranges and the geographical distribution of the genus Todites in China are discussed and reviewed. Available data show that Todites mostly occurs in the Late Triassic to Middle Jurassic of China. The genus was widely distributed in both the Northern and Southern Floristic Provinces of China, and especially abundant and diverse in the Southern Floristic Province.  相似文献   

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