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1.
Eifelian ammonoids are described for the first time from the Central Kyzylkum Desert (Uzbekistan, Navoiy Region, Aristantau Mountains). The ammonoid assemblage includes the typical Eifelian genera Fidelites, Subanarcestes (a new species S. aristanensis Nikolaeva sp. nov. is described), and Cabrieroceras, found in association with brachiopods, conodonts, and dacryoconarids. The ammonoid assemblage is similar to that from the Chote? beds of Barrandien and their equivalents in the Urals, Salair, Germany, and Morocco (Subanarcestes macrocephalus Zone), suggesting a connection between the Eifelian Kyzylkum Basin, which was part of the Turkestan Paleoocean, and European, North African, Siberian, and Uralian basins. The ammonoids studied are not associated with black shale and apparently existed in normal marine environments.  相似文献   

2.
Psammosteiforms, including Tartuosteus (?) zheleznogorskensis, sp. nov. and Psammosteus cf. P. praecursor Obruchev, from the Lower Frasnian (Upper Devonian) of the Mikhailovskii Mine (Kursk Region) are described. Agnathans, placoderms, crossopterygians, and acanthodians from this locality are determined. The similarity of the Mikhailovskii Fish Assemblage to the assemblage of southern Timan suggests it be assigned to the Upper Timan Regional Stage.  相似文献   

3.
Middle-Late Devonian Radiolarians are recorded for the first time in the southern Ural Mountains in Bashkortostan, in a section of Kariukmas Mountain (Upper Eifelian) and on the southern slope of Argagan Mountain (Middle Frasnian). The new Late Eifelian assemblage is composed of 17 species of 11 genera, and Middle Frasnian radiolarians comprise 13 species of 7 genera of spherical, discoidal, pylomate, and spiny radiolarians. A new species, Primaritripus kariukmasensis, sp. nov., is described. The prevalence of discoidal forms in the oryctocenosis suggests shallow marine conditions in the Late Eifelian and Middle Frasnian basins. Two new biostratons, the Upper Eifelian beds with Primaritripus kariukmasensis and Middle Frasnian beds with Primaritripus chuvashovi, are established based on radiolarians.  相似文献   

4.
The Lower Devonian beds of the Bechasyn zone of the Northern Caucasus (Kabardino-Balkaria, middle reaches of the Malka River) contain an assemblage of the Early Emsian Ammonoids including the characteristic genera Erbenoceras, Mimosphinctes, Teicherticeras, Mimagoniatites, and Gyroceratites. The taxonomic composition of the assemblage is similar to that of synchronous assemblages of Turkey and Tian Shan, differing from the assemblage of Morocco by the presence of Teicherticeras. Different approaches to the taxonomy of the family Teicherticeratidae are discussed and it is concluded that it is in need of serious revision. A new species Teicherticeras lakhranense is described.  相似文献   

5.
The Late Viséan (Early Carboniferous) ammonoid species Goniatites sphaericus (Sowerby, 1814) is revised with the use of the type material. With respect to conch morphology, suture line and particularly shell ornament, it is regarded as a senior synonym of the species Goniatites fimbriatus (Foord and Crick, 1897) and must therefore be re-established as an important index fossil for the ammonoid stratigraphy of the Rhenohercynian and Subvariscan shelves. The Goniatites fimbriatus Zone has been re-named Goniatites sphaericus Zone on this basis. The study of ontogenetic changes in the conch parameters shows that intraspecific variation occurs within a wide range. In the whorl profile, variation is very high in small juveniles, while in the coiling rate, intermediate growth stages are more strongly affected.  相似文献   

6.
New Late Viséan and Early Serpukhovian ammonoids are described from the Verkhnyaya Kardailovka section (South Urals, Bashkortostan). The ammonoid assemblages allow the recognition of the Hypergoniatites?Ferganoceras Genozone and a correlation with the synchronous zonations of North Africa, Spain, and China. The new species Ferganoceras constrictum sp. nov., Dombarites clemens sp. nov., and Hypergoniatites kardailovkensis sp. nov. are described.  相似文献   

7.
Terrestrial gastropods occur in many North African localities in Eocene continental deposits. Here we analyse the faunal assemblage from the Hamada de Méridja Formation in southwestern Algeria, dated as Early to Middle Eocene on the basis of charophytes. The assemblage consists of three closely related species that to date have been classified either in the extant Madagascan genus Leucotaenius v. Martens, 1860, or in the SW European Eocene genera Romanella Jodot, 1957 and Vicentinia Jodot, 1957. This is rejected for shell morphological and phylogeographical reasons, and a new classification as Maghrebiola gen. nov. is proposed. Maghrebiola is tentatively placed in the South American family Strophocheilidae, as species from the Early Eocene Itaboraí Basin of Brazil, currently placed in the genus Eoborus Klappenbach and Olazarri, 1970 in the family Strophocheilidae, superfamily Acavoidea, have a very similar shell habitus. This record possibly extends the known geographical range of the Strophocheilidae into the African continent during the Eocene. Immigration of this stock into North Africa during the Cretaceous via a still existing plate connection is assumed. An attribution of Maghrebiola to the African family Achatinidae is unlikely for shell morphological reasons despite certain habitus similarities, although the Priabonian genera Arabicolaria and Pacaudiella from Oman most likely belong into this family, and not to the Vidaliellidae as originally proposed. Possible causes for the very low diversity of the assemblage are mainly unfavourable living conditions, i.e. a relatively dry climate resulting in sparse vegetation and only occasional presence of water bodies, which may have had increased salinities, accounting for the lack of freshwater mollusks. The absence of any competing large gastropods may possibly have facilitated high intraspecific variability leading to sympatric occurrence of three closely related species, due to the animals occupying a wide range of available ecological niches. As the species discussed here have also been attributed to the genera Romanella and Vicentinia in the Vidaliellidae, we provide an appendix with annotated characterisations of most genera of the Vidaliellidae and list the nominal species assigned to them. This family is tentatively placed in the South American superfamily Orthalicoidea; its stock would have similarly immigrated from South America, but have successfully colonized mainly SW Europe, with only one Eocene species [Romanella kantarensis (Jodot, 1936)] recognized in Algeria.  相似文献   

8.
This paper continues our revision of Yu.L. Pelman’s collection of the superfamily Acrotheloidea (phosphatic brachiopods) and of our own material from the Early–Middle Cambrian of the Siberian Platform. The following representatives of the superfamily Acrotheloidea (order Lingulida, class Linguliformea) are restudied and revised based on new techniques: the genus Botsfordia (family Botsfordiidae Schindewolf, 1955) and the genera Acrothele, Eothele, and Orbithele (family Acrothelidae), which are widespread on the Siberian Platform. Only one out of the three Acrothele species described by Pelman is recognized as a valid species, and one new species of this genus that comprises some part of the brachiopods that Pelman figured and placed in another taxon is described. All these species are described using data on shell microsculpture and microstructure. In addition, the genera Eothele and Orbithele are described for the first time from the Siberian Platform.  相似文献   

9.
Lower Callovian deposits (subpatruus and koenigi ammonite zones) in the Mikhailovskii Mine section (Central Russia, Kursk Region) yielded 13 ostracode species (two of them are new) belonging to ten genera. This ostracode assemblage corresponds to ostracode beds with Praeschuleridea wartae-Pleurocythere kurskensis. The stratigraphic range of these beds corresponds to three ammonite biohorizons: Chamoussetia crobyloides, Kepplerites gowerianus gowerianus, and K. indigestus. Three distinct ostracode assemblages have been defined in the section based on their taxonomy and occurrence pattern. Two new species, Pleurocythere kurskensis sp. nov. and Pseudohutsonia wienholzae sp. nov., are described.  相似文献   

10.
The Early Triassic is a critical interval for the study of recovery from the terminal Permian mass extinction, as there are small-scale extinction events, which may have contributed to the delayed recovery. The systematic measuring and sampling of a 12-m-thick section at the Mokrice locality in eastern Slovenia has resulted in the recovery of a conodont fauna from the Olenekian beds. Four conodont zones have been recognized. These zones are in ascending order as follows: the Hadrodontina aequabilis Zone, Platyvillosus corniger Zone, Platyvillosus regularis Zone, and Triassospathodus hungaricus Zone. These conodont zones confirm the proposed conodont biozonation sequence in western Slovenia and have correlation value especially for the western marginal Tethys. Multielement conodont apparatuses of Triassospathodus hungaricus and Platyvillosus regularis have been reconstructed based on conodont elements that were recently obtained from the Slovenian sections. Although the S2element was not found, the apparatus indicates that the conodont species “Spathognathodushungaricus should be assigned to the genus Triassospathodus.  相似文献   

11.
Triassic radiolarians from Kotel’nyi Island (New Siberian Islands, Arctic Region) are studied. Radiolarians occur in the Middle and Upper Triassic beds, which are well dated by ammonoids, nautiloids, and bivalves. In the Middle Triassic beds, which are composed of dark gray and black clays and claystones with interbeds of combustible schist, siltstone, clayey limestone, and many phosphatic concretions, the following two assemblages are recognized: (1) a Late Anisian assemblage, including Glomeropyle clavatum Bragin, sp. nov., G. boreale Bragin, G. manihepuaensis Aita, G. insulanum Bragin, sp. nov., Triassospongosphaera multispinosa (Kozur et Mostler), Tetraspongodiscus hibernus Bragin, sp. nov., T. borealis Bragin, sp. nov., Eptingium abditum Bragin, sp. nov., E. manfredi Dumitrica, Spongostephanidium japonicum (Nakaseko et Nishimura), and Ladinocampe vicentinensis Kozur et Mostler; (2) Late Ladinian assemblage, with Muelleritortis firma (Gorican), M. kotelnyensis Bragin, sp. nov., Tiborella nivea Bragin, sp. nov., Pseudostylosphaera goestlingensis (Kozur et Mostler), P. omolonica Bragin, Triassospongosphaera multispinosa (Kozur et Mostler), Sarla cincinnata Bragin, sp. nov., S. obscura Bragin, sp. nov., S. prava Bragin, sp. nov., and Eonapora stiriaca Bragin, sp. nov. The Upper Triassic beds, composed of gray and black clays and claystones with lenses of clayey limestones, with sideritic and phosphatic-calciferous concretions have yielded (1) an Early Carnian assemblage, with Pentactinocarpus colum Bragin, sp. nov., Glomeropyle cuneum Bragin, sp. nov., G. algidum Bragin, sp. nov., G. aculeatum Bragin, sp. nov., Kahlerosphaera isopleura Bragin, sp. nov., Stauracanthocircus folium Bragin, sp. nov., Tetraspongodiscus uncatus Bragin, sp. nov., Poulpus costatus (Kozur et Mostler), Eonapora robusta Kozur et Mostler, Planispinocyrtis kotelnyensis Bragin, sp. nov., Annulotriassocampe baldii (Kozur), and Pseudoeucyrtis annosus Bragin, sp. nov.; (2) a Middle-Late Carnian assemblage with Pseudostylosphaera glabella Bragin, sp. nov., P. gracilis Kozur et Mock, P. voluta Bragin, sp. nov., P. gelida Bragin, sp. nov., Kahlerosphaera unca Bragin, sp. nov., K. aspinosa Kozur et Mock, K. fuscinula Bragin, sp. nov., K. acris Bragin, sp. nov., Capnuchosphaera kuzmichevi Bragin, sp. nov., C. triassica De Wever, C. angusta Bragin, sp. nov., Sarla intorta Bragin, sp. nov., S. compressa Bragin, sp. nov., S. aequipeda Bragin, sp. nov., Betraccium irregulare Bragin, B. kotelnyensis Bragin, sp. nov., Spongotortilispinus carnicus Kozur et Mostler, S. subtilis Bragin, sp. nov., Dumitricasphaera simplex Tekin, D. aberrata Bragin, sp. nov., D. arbustiva Bragin, sp. nov., Zhamojdasphaera epipeda Bragin, sp. nov., Z. proceruspinosa Kozur et Mostler, Vinassaspongus subsphaericus Kozur et Mostler, Palaeosaturnalis triassicus Kozur et Mostler, Paronaella concreta Bragin, sp. nov., P. aquilonia Bragin, sp. nov., Tetraspongodiscus cincinnalis Bragin, sp. nov., Annulotriassocampe baldii (Kozur), Canoptum zetangense Wang et Yang, Whalenella speciosa (Blome), Syringocapsa turgida Blome, Droltus gelidus Bragin, sp. nov., and D. niveus Bragin, sp. nov.; (3) an Early Norian assemblage with Pseudostylosphaera glabella Bragin, sp. nov., P. gelida Bragin, sp. nov., P. voluta Bragin, sp. nov., Kahlerosphaera retunsa Bragin, sp. nov., Capnuchosphaera deweveri Kozur et Mostler, Sarla globosa Bragin, sp. nov., Palaeosaturnalis mocki Kozur et Mostler, Paronaella aquilonia Bragin, sp. nov., Syringocapsa turgida Blome, and Droltus gelidus Bragin, sp. nov.; (4) a Middle Norian assemblage with Sarla globosa Bragin, sp. nov., Sarla sp., Syringocapsa turgida Blome, Canoptum sp., and Laxtorum? sp. The fact that these assemblages include taxa that are recorded more southerly, including paleotropical localities, and support dating based on mollusks, enables the use of these data for Boreal-Tethyan correlation. The greatest similarity to Tethyan associations is observed in the Late Carnian and Early Norian, that is, the periods of the greatest penetration of thermophilic mollusks into this basin. A total of 69 radiolarian species of 3 orders, 18 families, and 29 genera are described; 44 species are newly described; the stratigraphic and geographical ranges of the majority of taxa are improved considerably.  相似文献   

12.
A new nodosariid genus Dagysina gen. nov. with the type species Dagysina novosibirica sp. nov. is described from the Norian deposits of Kotel’ny Island, New Siberian Islands. A close phylogenetic relationship between Dagysina and the Early Liassic Frondiculinita is revealed based on morphological resemblance and an identical geographic range.  相似文献   

13.
Two new genera (monotypic Samarabatrachus gen. nov. (S. bjerringi sp. nov.) and Syrtosuchus gen. nov. (including S. samarensis (Sennikov, 1981) and S. morkovini sp. nov) and a new species of the genus Selenocara Bjerring (S. rossica sp. nov.) are described based on revision of the original material of the form previously known as Wetlugasaurus samarensis. The genera Selenocara and Samarabatrachus gen. nov. positioned at the base of radiation of Triassic capitosaurids are combined into a new subfamily, Selenocarinae subfam. nov. The genus Syrtosuchus gen. nov., which is undoubtedly a derivative of early capitosaurids (Selenocara or a closely related genus), shows some typical benthosuchid features and is assigned to a separate benthosuchid subfamily, Syrtosuchinae subfam. nov. The diagnoses of the genera Wetlugasaurus Riabinin and Selenocara are amended. For the territory of the Obschii Syrt Highland, the genera Selenocara, Samarabatrachus gen. nov., and Syrtosuchus gen. nov. are regarded as key members of a separate Early Triassic tetrapod assemblage (Selenocara–Syrtosuchus Fauna), which is intermediate between the Tupilakosaurus and Benthosuchus faunas and dated Late Induan (Dienerian).  相似文献   

14.
The ammonoid family Sirenitidae from the Upper Carnian yakutensis Zone of northern Middle Siberia and Northeastern Asia is revised. A new genus Orientosirenites gen. nov. with the type species O. bytschkovi sp. nov. is established based on the study of the main morphological characters of the shell. The new genus and the species O. bytschkovi are described and the species O. yakutensis (Kiparisova) is redescribed. The new data allow the taxonomic composition and the distribution of the Carnian ammonoids of the Boreal Realm to be updated.  相似文献   

15.
Fossiliferous Quaternary sedimentary beds in the Santa Lucía Basin (southern Uruguay) are potentially useful for the study of the last occurrences of extinct taxa, as well as the environmental and climatic patterns in the late Pleistocene to the early Holocene. They have provided a chronological framework (AMS 14C and Optically Stimulated Luminescence dates), a mammalian diversity and interpretations of last occurrence, the climatic-environmental setting, and some associated biogeographic processes. The ages produced encompass the last 30 to 7 ka interval (latest Pleistocene-early Holocene). The mammalian assemblage (36 genera, 24 species) includes typical South American late Pleistocene mammals, extinct species of extant genera, and some extant species that still exist elsewhere on the continent. The preservation pattern includes articulated and semi-articulated skeletons of large and small mammals. The presence in the southern Uruguayan Pampean area of some mammals currently inhabiting Patagonia, northwest and central Argentina (Dolichotis, Galea, Microcavia, Chaetophractus, Lagostomus, and Vicugna) is explained by the predominance of open areas and cold climates associated with the Last Glacial Maximum. The mammalian record depicts local extinctions or shifting ranges occurring in latest Pleistocene or early Holocene. The sedimentary chronological framework and taphonomic features suggest the persistence into the early Holocene of Eutatus seguini, Morenelaphus brachyceros, Equus neogeus, Hemiauchenia sp., Lama sp., and Vicugna sp. Glyptodon and Glossotherium seem to persist at least to the latest Pleistocene. This pattern can substantiate the hypothesis that some megafauna and large mammals persisted for some millennia alongside people with extinction occurring before, during, and after human colonization.  相似文献   

16.
The recent recognition of the earliest Andean Tithonian ammonite fauna (Picunleufuense Zone) has allowed a balanced classification of the ataxioceratid ammonites, reflecting their phylogenetic relationships. The Picunleufuense Zone fauna, first recognized in the Neuquén Basin at the base of the Vaca Muerta Formation, is represented by numerous records of sparse ammonite faunas from Antarctica, the Austral Basin and the Tarapacá Basin (N. Chile and S. Peru). These Southeastern Pacific faunas include the Tithonian genera Indansites, Choicensisphinctes, Zapalia, Krantziceras (Tithonian–lower Berriasian) and Platydiscus. These five genera are grouped in a new subfamily established in this paper: Zapaliinae subfam. nov. (type genus: Zapalia). The origin of Indansites and Choicensisphinctes (possibly via Indanistes) from Lithacoceras is discussed. Zapalia must have been originated from Indanistes in the upper Proximus Zone. Platydiscus could have been originated from Krantziceras. The Tithonian Southeastern Pacific ataxioceratids (Zapaliinae subfam. nov.) form a group well separated from the Tithonian Indo-Madagascan Virgatosphinctinae.  相似文献   

17.
A new psammosteid, Oredezhosteus kuleshovi gen. et sp. nov., from the Amata Regional Stage (Lower Frasnian) of the Leningrad Region is described. In addition, Psammosteus livonicus Obruchev from beds of the same age from Latvia is included in the new genus. The major diagnostic characters distinguishing Oredezhosteus gen. nov. from Psammosteus Agassiz are the large rounded striated tubercles, which cover more than half width of the branchials, and the long base of the branchial plates.  相似文献   

18.
Middle Devonian conodonts from the Si Phai section in NE Vietnam are described. The section ranges from the Middle Devonian ensensis to timorensis conodont zones to the Late Devonian rhomboidea conodont Zone. A rich overall assemblage is described, including 27 taxa of species or subspecies rank and 11 taxa described in an open nomenclature. Among the dominant Polygnathus forms, four new taxa are described: Polygnathus linguiformis saharicus subsp. nov., Polygnathus linguiformis vietnamicus subsp. nov., Polygnathus rhenanus siphai subsp. nov., and Polygnathus xylus bacbo subsp. nov. Conodont assemblages are attributed to polygnathid, polygnathid-klapperinid, and klapperinid conodont biofacies representing hemipelagic to pelagic environments. The klapperinid biofacies, unreported in the previous literature, are here attributed to offshore areas of the external shelf. The taxonomic compositions of the studied conodont assemblages, as well as their CAI characteristics (CAI 4–5), suggest a palaeogeographic affinity of the studied strata to the Chinese Devonian Guangxi Basin, and the South China Terrane in general. Furthermore, the conodont biofacies and the palaeogeographic distribution of the fauna are discussed.  相似文献   

19.
Fungal endophytes are the most ubiquitous and highly diverse microorganisms that inhabit the interior of healthy plants. They are important in plant ecology and offer untapped potential to improve plant health and productivity in agroecosystems. The endophytic assemblage of avocado is poorly understood; therefore, surveys of fungal endophytes of Persea americana Mill. (Avocado) in South Florida organic and conventional orchards were conducted. A total of 17 endophytic fungal species were recovered from healthy avocado terminal branches. Endophytic fungal species were identified by rDNA sequencing of the internal transcribed spacer (ITS) region, using UNITE Species Hypotheses to reliably assign a taxon name, and determined as belonging to the genera Alternaria, Cladosporium, Colletotrichum, Corynespora, Diaporthe, Lasiodiplodia, Neofusicoccum, Neopestalotiopsis, Phyllosticta, and Strelitziana. Endophyte community assemblage differed between organic and conventional agroecosystems. This is the first report of Alternaria eichhorniae, Cladosporium tenuissimum, Corynespora cassiicola, Colletotrichum alatae, Diaporthe fraxini-angustifoliae, Lasiodiplodia gonubiensis, Neofusicoccum algeriense, Neofusicoccum andinum, Neopestalotiopsis foedans, Phyllosticta capitalensis, and Strelitziana africana as endophytes of avocado. Evaluation using pathogenicity tests on avocado leaves and terminal branches showed that endophytic fungal isolates did not cause disease symptoms.  相似文献   

20.
Six new genera and eight new species are described from South and Central Americas, South Africa, and Southeastern Asia. Illustrations of the male genitalia of the type species of the genera Duiliopsis Bergevin and Perindus Emeljanov are given. The generic name Duiliopsis is synonymized with Duilius Stål. The synonymy of the generic name Hemitropis Fieber with Duilius is supported.  相似文献   

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