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1.
Ammonites from the Riasanites rjasanensis Zone (Ryazanian Stage of the Russian Platform) of the family Neocomitidae are considered. The new species Mazenoticeras robustum sp. nov. and M. ceccai sp. nov. are described. Other members of this genus and of the genera Malbosiceras and Pomeliceras are identified in open nomenclature.  相似文献   

2.
The ammonite genus Subalpinites is known from the Berriasian of southern and central Europe, North Africa, Mangyshlak, and Ryazanian Stage of Central Russia. New species are described: S. gruendeli sp. nov., S. faurieformis sp. nov., S. remaneiformis sp. nov. These species and also S. krischtafowitschi Mitta characterize the lower subzone of the Riasanites rjasanensis Zone in the Moscow Region. The upper subzone of this zone in the Ryazan Region contained members of Subalpinites identified in open nomenclature.  相似文献   

3.
A new ammonite genus Riasanella is described from the Ryazanian Stage of the Russian Platform (type species R. rausingi sp. nov.). The new species R. plana sp. nov., R. olorizi sp. nov., and R. riasanitoides sp. nov. are described. These species come from the lower, strongly condensed beds of the Riasanites rjasanensis Zone of the Moscow Region. The upper subzone of this zone in the Ryazan Region contains specimens of Riasanella, identified in open nomenclature. The new genus is assigned to the family Himalayitidae; one of its species is a possible ancestor of Riasanites Spath.  相似文献   

4.
The short geochronological span and wide geographic distribution of the genus Hectoroceras in the Boreal Paleogeographic Superrealm make it exceptionally important for correlation of the Volgian–Ryazanian boundary beds. The Ogarkovo Section on the Unzha River (Kostroma Region), which is essential for this correlation, is described. The revised genus Hectoroceras includes the type species H. kochi Spath, H. larwoodi Casey, H. tolijense (Nikitin), and its microconch H. pseudokochi (Mesezhnikov), the latter two previously assigned to the genus Shulginites Casey, 1973 which is here considered as a junior subjective synonym of Hectoroceras. The FAD of Hectoroceras kochi is an interregional marker for Panboreal correlation, and the coincidence of this event with the invasion of ammonites of Tethyan origin into the Central Russian ecotone improves the prospects for a Boreal – Tethyan correlation of the Jurassic–Cretaceous boundary interval.  相似文献   

5.
Ammonites of the genus Kachpurites are characteristic of the lower part of the Upper Volgian Substage of the Russian Platform. K. fulgens fulgens (Trautschold), K. fulgens tscheremkhensis Mitta et al., K. subfulgens (Nikitin) are established in the fulgens zone. The genus Kachpurites also includes ammonites previously described as Anivanovia mola Kiselev. The holotype of Volgidiscus singularis Kiselev belongs to K. mola, wheras some of its paratypes belong to Craspedites krylovi Prigorovsky. The generic name Anivanovia Kiselev, 2003 is considered as a junior subjective synonym Kachpurites Spath, 1924. The beds with Kachpurites mola are in the basal part of the Upper Volgian subditus Zone. Species of the genus Kachpurites are described, and macro- and microconchs are established within the species.  相似文献   

6.
The genus Riasanites, represented in Central Russia by two successive dimorphic species, is revised. R. swistowianus is found in the basal beds of the rjasanensis Zone. Its descendant R. rjasanensis is also found in this zone, but upwards in the section, including the beds with Surites spasskensis and Externiceras solowaticum. The representatives of Riasanites from the Crimea and Northern Caucasus are assigned to two species, R. crassicostatus and R. maikopensis, respectively. It is suggested that Riasanites evolved from Sub-Mediterranean Himalayatidae, which migrated from the Western Tethys via the Polish Passage into the Central Russian Basin, and from there to Mangyshlak, the Northern Caucasus, and the Crimea.  相似文献   

7.
Study of the shells of phylloceratids from the kochi Zone (Berriasian) of north-central Siberia (Boyarka River, basin of the Kheta River) allowed their assignment to the genus Boreophylloceras Alekseev et Repin, 1998. A new species B. densicostatum is described.  相似文献   

8.
Because of the relatively thick succession exposed in the Msila area, new bed-by-bed sampling has been carried out in order to investigate late Tithonian ammonites and the correlation between biostratigraphic scales based on ammonites and calpionellids. The outcrop begins with Lower Tithonian beds assigned to the Fallauxi Zone. Ammonites have been found that allow recognition in the same section both Fallauxi and Ponti Zones. The most significant species are: Simoceras admirandum Zittel, which is the marker of the upper subzone of the Fallauxi Zone, i.e. the Admirandum/Biruncinatum Subzone, and several species of the genus Lemencia and Burckhardticeras peroni (Roman), that characterize the Ponti Zone. Ammonites that belong to the Microcanthum Zone appear in bed 18. This zone is usually subdivided into two subzones, of which only the lower one, the Simplisphinctes Subzone, has been recognized. The upper Transitorius Subzone has been recognized on the basis of the occurrence of Moravisphinctes fischeri (Kilian). The last ammonite unit, the Durangites Zone, is easily recognizable because of the occurrence of species of the genera Durangites and Protacanthodiscus. The section ends with the beginning of the Berriasian, which is characterized by a well-exposed, ammonite-rich bed of the Jacobi Zone. Correlation of the ammonite zones with calpionellid zones has been investigated. The Chitinoidella Zone is characterized by calpionellids with microgranular tests that appear in the ammonite Admirandum/Biruncinatum Subzone with species of the Dobeni Subzone, which extends up to the Ponti Zone. Representatives of the Boneti Sub-Zone appear in bed 16, which probably correlates with the base of the ammonite Upper Tithonian Microcanthum Zone. Two horizons have been distinguished within the calpionellid Subzone A3.  相似文献   

9.
According to the present practice of Hungarian greenhouse sweet pepper production, only exotic agents are used for biological control purposes against thrips pests. The suitability for biological control of the second instars of an indigenous species, the common crab spider, Xysticus kochi Thorell (Araneae: Thomisidae) was tested on thrips species, Frankliniella occidentalis (Pergande) and Frankliniella intonsa (Trybom) (Thysanoptera: Thripidae) using a cage set-up on greenhouse sweet pepper plants. Effects of introducing second instars of X. kochi on thrips infested plants were judged by assessing the degree of aesthetical damage, the commercial value of the fruits (degree of economic loss) and the quality composition of the harvested peppers. The estimated damaged surface unit was significantly lower in control plants than in plants infested by F. occidentalis. A significant effect of the spider introduction was observed in all of the pepper quality indicators applied. We suspect that direct Xysticus predation or any other predator-induced effect resulted in reduced levels of damage on harvested peppers. However, further investigation is needed to detect the origin (e.g., predation and non-predation effects) of the suppression of thrips damage. Our results suggest that X. kochi could be an effective component of greenhouse antagonistic fauna and the application of mulch may encourage the effectiveness of spiderlings. An erratum to this article can be found at  相似文献   

10.
The ant genus Solenopsis Westwood 1840, is recorded for the first time in Saudi Arabia. The worker caste of S. saudiensis n. sp., collected in Riyadh is described and illustrated. This resembles S. cooperi Donisthorpe 1947, and S. kochi Finzi 1936. A revised key to the Arabian species is given together with ecological and biological notes. S. saudiensis n. sp. is identified by the following characters: Anterior clypeal margin with a central pair of stout projecting teeth and a lateral pair of short, broad basal blunt teeth; eyes with two minute facets; funicular segments 2–7 about twice as wide as long; propodeum short and low with the basal face making a continuous arc with the declivity; and petiole as long as broad in dorsal view.  相似文献   

11.
González  Exequiel R.  Watling  Les 《Hydrobiologia》2001,464(1-3):175-199
Hyalella is the only epigean freshwater amphipod present in Chile . H. chiloensis, H. costera and H. kochi are here described and illustrated. H. kochi is distributed in highland areas of the Andes in northern Chile; it is characterized by a short ramus on uropod 3 and a hammer-shaped gnathopod 1. H. costera and H. chiloensis are present in lowland areas, the latter restricted to the southern part of the country. These two species have a long ramus on uropod 3, but they differ in the shape and length of the palp on maxilla 1, the setation of peraeopods 3, 4, and telson. The presence in Chile of H. fossamancinii Cavalieri, 1959 is also reported here.  相似文献   

12.
This paper presents the results of the study of ammonites of the family Himalayitidae from the Surites spasskensis Zone of the Ryazanian Stage of Central Russia. The new taxa Transcaspiites tscheffkini sp. nov., T. transitionis sp. nov., and Karasyazites gen. nov., with the type species Subalpinites bajarunasi Luppov, are described. The hypothesis that Transcaspiites Luppov originated from the genus Riasanites Spath is proposed. The analysis of the taxonomic composition of ammonites allows the Neocosmoceras–Septaliphoria semenovi regional zone of Mangyshlak to be correlated with the Spasskensis zone of the standard scale of the Ryazanian Stage.  相似文献   

13.
Revision of the Siberian Middle- and Upper Volgian ammonites, which were previously identified as Craspedites mosquensis Geras. allow their re-identification as a new species C. schulginae sp. nov.  相似文献   

14.
Shu-Zhong Shen  G.R. Shi 《Palaeoworld》2009,18(2-3):152-161
A brachiopod fauna comprising nine species in eight genera from three closely spaced stratigraphic horizons of the same stratigraphic section is described for the first time from the Laibin Limestone in the uppermost part of the Maokou Formation in the Guadalupian/Lopingian (G/L) GSSP section at Penglaitan, Guangxi Autonomous Region, South China. The brachiopod assemblages are bracketed between two conodont zones: Jinogondolella xuanhanensis Zone below and Jinogondolella granti Zone above and, therefore, they can be safely assigned to the latest Capitanian in age. However, all but one of the nine brachiopod species from the Laibin Limestone carry strong early Lopingian (Wuchiapingian) aspect. Thus, the discovery of this brachiopod fauna not only suggests that some Lopingian brachiopod species had already appeared in the late Guadalupian (Capitanian); more importantly, it has also highlighted the fact that both the previously noted pre-Lopingian life crisis (or end-Guadalupian or Middle Permian mass extinction) and Lopingian recovery/radiation actually occurred in late Capitanian times, sometime before the G/L chronostratigraphic boundary. So far, the Penglaitan GSSP section provides the highest-resolution disappearance patterns of different fossil groups around the G/L boundary.  相似文献   

15.
A new genus, Boreomica gen. nov., is established; it comprises small-sized gastropods widespread in the Jurassic of the Russian Plate, the taxonomic position of which was ambiguously treated by previous authors. The new genus is assigned to the family Rissoidae. The species composition and stratigraphical and geographical distribution of the genus and its species are discussed. From the Jurassic of the Russian Plate, Callovian Boreomica exigua (Gerasimov, 1992), the type species of the genus, and Kimmeridgian–Volgian Boreomica undulata (Tullberg, 1881), and members of the genus without species status from the Bathonian and Upper Oxfordian are described. Conchological polymorphism of species connected with their eurybiontic characteristics is discussed. Based on the study of samples of the species B. exigua from different types of facies, two subspecies are recognized, B. exigua exigua and B. exigua arenosa subsp. nov. Finds of gastropods morphologically similar to Boreomica are discussed: Katosira? sp. from Mitta et al., 2004, “Procerithium?” volgense Gerasimov, 1955, “Eulima” pusilla Tullberg, 1881, and “Hudlestonella” caleptra sensu Gerasimov, 1992 are considered. It is concluded that E. pusilla and H. caleptra are unknown zygopleurids, Katosira? sp. is likely a poorly preserved Katosira, and “Procerithium?” volgense is represented by a mixture of several species belonging to different genera: several zygopleurid species, the rissoids Boreomica undulata and Bralitzia. Shells of P. volgense in the P.A. Gerasimov’s collection from the Craspedites nodiger Zone are described as Laevipleura sp.  相似文献   

16.
In this paper a magnetostratigraphically calibrated biozonation of the Miocene–Pliocene continental record of the Guadix–Baza Basin (south‐eastern Spain) is presented. This biozonation is based on a rodent succession which ranges from the latest Miocene (c. 6 Ma) to the latest Pliocene (c. 2.6 Ma). A total of nine biozones have been defined for the late Miocene and Pliocene, all of them based on the range or concurrent‐range of rodent species: Apodemus gudrunae – Apocricetus alberti Zone, Apocricetus barrierei Zone, Paraethomys aff. abaigari Zone, Trilophomys Zone, Mimomys davakosi Zone, Dolomys adroveri Zone, Mimomys hassiacus Zone, Mimomys polonicus Zone and Kislangia ischus Zone. A magnetobiostratigraphical correlation has been established between these biozones and the standard ATNTS scale, on the basis of the palaeomagnetic analysis carried out on the sections of Negratín, Botardo‐1 and Gorafe. The correlation has been completed with previous palaeomagnetic analysis in the sections of Galera and Zújar. The magnetobiostratigraphical correlation here established indicates a late Messinian age for the Apodemus gudrunae – Apocricetus alberti Zone, a Zanclean age for the Apocricetus barrierei, Paraethomys aff. abaigari, Trilophomys and Mimomys davakosi zones and a Piazencian age for the Mimomys hassiacus, Mimomys polonicus and Kislangia ischus zones. The Dolomys adroveri Zone is mostly Zanclean in age, but its uppermost part belongs to the Piazencian. Therefore, unit MN13 is correlated with the late Messinian, MN14 is correlated with the early Zanclean, most of MN15 is correlated with the late Zanclean, while the uppermost part of MN15 and MN16 are correlated with the Piazencian.  相似文献   

17.
Based on a systematic study of Tremadocian graptolites from the Early Ordovician Yehli Formation at Dayangcha, Baishan of Jilin, NE China, a revised graptolite zonation is proposed for the Tremadocian rocks in the area. In ascending order, the graptolite zones include theRhabdinopora flabelliformis parabola Zone, theAnisograptus matanensis Zone, thePsigraptus jacksoni Zone and theAorograptus victoriae Zone. The first three zones are discussed with their definitions and durations clarified, whereas the last zone is introduced for the first time as a replacement of the formerAdelograptus-Clonograptus Zone. The entire Yehli Formation is considered to be older than the late Tremadocian Hunneberg Substage of Scandinavia, the latter being represented by the carbonate-dominated basal part of the overlying Liangchiashan Formation where no graptolites have so far been discovered. The Tremadocian succession in the Dayangcha area is regarded as being representative of the North China (Sino-Korea) Palaeoplate, and a correlation of the Tremadocian graptolite sequence with those of other continents is suggested. Nine species belonging toDendrograptus, Aspidograptus, Callograptus andAirograptus of the family Dendroidae, and eight species ofPsigraptus, Adelograptus, Aorograptus andKiaerograptus of the family Anisograptidae are described and some are revised in the present paper. Among the important revisions are the reconstructed proximal development ofPsigraptus jacksoni based on partially three-dimensional specimens from the area, and the complex thecal structures ofAspidograptus.   相似文献   

18.
19.
The Aladağ Unit is one of the main tectonic units in the Tauride Belt, located in southern Turkey. It includes a continuous Paleozoic carbonate sequence encompassing the mid-Carboniferous boundary, with outcrops being especially well exposed in the Hadim region. The boundary succession lithology is mainly composed of carbonates with intercalated quartz arenitic sandstone layers. Based on foraminifers, four biostratigraphic zones have been defined in the interval from the Upper Serpukhovian to the Lower Bashkirian. These zones are, in ascending order: the Eostaffella ex gr. ikensisE. postmosquensis Zone (Zapaltyubinsky Horizon, Upper Serpukhovian); the Plectostaffella jakhensisP. bogdanovkensis Zone, and the Millerella marblensis Zone (Bogdanovsky Horizon, lower Bashkirian); and the Semistaffella sp. Zone (Syuransky Horizon, lower Bashkirian). The mid-Carboniferous boundary occurs between the Eostaffella ex gr. ikensisE. postmosquensis Zone and the Plectostaffella jakhensisP. bogdanovkensis Zone. Boundary beds are characterized by eight, repeatedly occurring microfacies types, namely: (1) coated crinoidal packstone; (2) coated bioclastic grainstone; (3) oolitic grainstone; (4) oolitic packstone-grainstone; (5) intraclastic grainstone; (6) mudstone-wackestone; (7) quartz-peloidal packstone; and 8) quartz arenitic sandstone. Based on microfacies stacking patterns, various types of shallowing-upward cycles have been recognized. Depositional sequences and sequence boundaries are correlatable with those described from North America and Russia and Carboniferous global sea-level curves. The duration of cycles has been estimated as 100 ky, suggesting that cycle periodicities correspond to the Milankovitch eccentricity band.  相似文献   

20.
The zonation of the Furongian Alum Shale in Scandinavia, based on olenid trilobites, is reviewed and revised. The current scheme is rooted in a detailed zonation introduced in the late 1950s with subzones that subsequently have been elevated to zonal rank. Ten of these zones are difficult to recognize in all Alum Shale districts, and a revised zonation is proposed, focused on unambiguous identification throughout Scandinavia. The difficulties in recognizing zones in some districts mostly relate to biofacies differentiation. Representatives of Ctenopyge are, for instance, common in palaeo-offshore areas, whereas pelturines are rare in these settings and vice versa in palaeo-inboard settings. The following modifications of the olenid zonation are proposed: the Olenus scanicus Zone is renamed the O. scanicusO. rotundatus Zone; the Ctenopyge similis and Ctenopyge spectabilis zones are replaced by the Sphaerophthalmus modestusSphaerophthalmus angustus Zone; the Ctenopyge tumida Zone is renamed the Peltura acutidensCtenopyge tumida Zone; the Peltura scarabaeoides Subzone is restored (as a zone) and replaces the Ctenopyge bisulcata and Ctenopyge linnarssoni zones. The Parabolina heres megalops (Sub)Zone is reinstated and replaces the Peltura paradoxa Zone; the Acerocarina granulata and P. costata zones are combined as the Acerocarina granulata–Peltura costata Zone. In addition, the name Proceratopyge nathorsti–Simulolenus alpha Zone is suggested for the polymerid zone corresponding to the upper Miaolingian Agnostus pisiformis Zone. The proposed changes reduce the number of Furongian Zones to 23, allocated to six superzones. No subzones are recognized, but some zones can potentially be subdivided for improved local correlation. The stratigraphical ranges of all Furongian olenid trilobites and agnostoids described from Scandinavia are summarized.  相似文献   

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