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1.
Dendroid graptolites from the Middle Devonian (Givetian, middlePolygnathus varcus Biozone) of the Rheinisches Schiefergebirge are described for the first time. The fauna of the Burgberg locality south of the Brilon reef comes from a black shale layer in a succession of calcareous debris flows. The fauna includes five species ofDictyonema andRuedemannograptus described in open nomenclature. The fragmentation of the material is conside-red as an indication of post-mortem transport.   相似文献   

2.
Seven further specimens of the hitherto only known Devonian phalangiotarbid Devonotarbus Poschmann, Anderson and Dunlop, 2005 are described. Thus, the genus is recorded from four different localities of Siegenian (Hombach and Burglahr) and Lower Emsian (Willwerath and Alken) age, respectively, but the specific identity of Siegenian and Emsian specimens remains unproven. The new material suggests that this Devonian phalangiotarbid possessed more than six eye lenses, tergites five and six fused into a diplotergite, and an almost terminally situated anal operculum. It thus notably deviates morphologically from its younger Permocarboniferous relatives, and a new family, Devonotarbidae nov. fam., is proposed to accommodate Devonotarbus.  相似文献   

3.
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   

4.
A new fossil arachnid,Xenarachne willwerathensis n. gen., n. sp. is described from the Lower Devonian (upper Lower Emsian) Klerf-beds of Willwerath, Germany. This intriguing fossil has a pedicel and pygidium, indicating that it belongs to the tetrapulmonate arachnids, but cannot be referred with confidence to any particular order. It is placed as Tetrapulmonata incertae sedis, though has similarities to whip spiders (Amblypygi) and spiders (Araneae).Xenarachne could even represent a very early spider, though the Devonian arachnid fauna could have included taxa which did not belong in any currently recognised order.Xenarachne may be an example of just such a fossil.  相似文献   

5.
The few isolated reports of agelacrinitid edrioasteroids (“Timeischytes”) from the Middle Devonian of the Eifel (Rhenish Massif, Germany) are revised. In this context, a specimen-rich but low-diversity edrioasteroid association is described from the threshold of the Eisen and Latistriatus Members of the Junkerberg Formation (Eifelian, Middle Devonian) of the Blankenheim Syncline. Predominantly, the autochthonously preserved edrioasteroids settled fixosessile-epibenthically on the frequent-occurring orthid brachiopod Schizophoria schnuri blankenheimensis and represent a wide spectrum of ontogenetic growth stages. They are associated with epibenthic brachiopods, microconchids, bryozoans, and auloporids—exemplifying synecological interactions. Roundish, shallow concavities with the shape and size of preserved adjacent edrioasteroids within encrusting colonies of the bryozoan Eostenopora clivosa are of special interest. It is suggested that the depressions represent former positions of the adjacent edrioasteroids. The new Bellastrella eifeliana n. gen. n. sp. is described, and genus Krama Bell, 1976 is reported from the Middle Devonian of Germany for the first time.  相似文献   

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Placoderms (Ptyctodontida), acanthodians (incl.Atopacanthus?ambrockensis n. sp.), actinopterygians, dipnoans and crossopterygians — including the first Middle Devonian osteolepids from the Rheinisches Schiefergebirge — are described from the lower Brandenberg Group of Hagen-Ambrock and Lasbeck (northern Sauerland, Northwest Germany). The composition of the fauna is similar to that of contemporaneous Scottish and Baltic Old Red localities, even though typical marine vertebrates are present too (e.g. selachians). This indicates — like the invertebrates — rather a marginal marine deposition.  相似文献   

8.
The arthrodires of the Eifelian Brandenberg Group of Hagen-Ambrock and Lasbeck (Northwest Germany) are described. A new tuberculated holonematid arthrodire (Holonema bruehni n. sp.) is represented by plates of the trunk shield and some plates of the head region. The tuberculation is here regarded as the plesiomorphic character of the Holonematidae compared to an ornamentation of ridges in advanced genera. This agrees with the stratigraphical occurrence of the new form. Additionally, several other plates belonging to at least three different taxa of coccosteid arthrodires have been found. Despite the absence of complete skeletons, the placoderm fauna is more diverse than the fauna of the classical Scottish Eifelian localities.  相似文献   

9.
Abstract: The Devonian fenestrate bryozoan, Schischcatella Waschurova, 1964 , possessed colonies in the form of low, erect bifoliate fronds that grew from an encrusting sheet‐like base with autozooecia arranged in biserial, bifurcating rows. This growth habit is unique in fenestrates, which normally had unilaminate arborescent colonies. Originally, Schischcatella was described from the Lower Devonian of Tajikistan. This article describes a new species, S. heinorum sp. nov., from the Middle Devonian of the Eifel (western Rhenish Massif, Germany) with additional material from the Lower Devonian of the Kellerwald (eastern Rhenish Massif, Germany). External and internal morphologies of this bryozoan have been studied using abundant material. The growth habit of Schischcatella suggests a completely different pattern of feeding currents than that in the normal fenestrate colony. The outflow of the filtered water occurred only on edges of colonies between rami. In the absence of chimneys (areas of vertical water expelling), such a functional morphology may have restricted extension of the colony in a distal direction. The evolution of Schischcatella is apparently an example of paedomorphosis, the genus evolved from an unknown semicosciniid species by the early ontogenetic interruption of colony development and further changes in the mode of growth.  相似文献   

10.
The Lower Eifelian Meinerzhagener Korallenkalk (= upper Cultrijugatus Beds) at Kierspe, Sauerland, contains a rich reefal fauna. Eight bryozoan species are described, two of them are new: the cystoporate Fistuliporella kierspensis n. sp. and the trepostome Leptotrypella sophiae n. sp. The bryozoans from the Meinerzhagener Korallenkalk shows distinct similarities to the Lower–Middle Devonian of Spain (Santa Lucía Formation, Emsian–Eifelian), and to the Middle Devonian (Eifelian) of Transcaucasia. The coral fauna comprises five tabulate corals and one rugose coral that document a paleobiogeographic relationship between Central and Eastern Europe and Central Asia. The associated fauna is represented by brachiopods, ostracods, and echinoderms. The studied limestones also commonly contain calcimicrobes represented by three species. The faunal and microfacial characteristics indicate a shallow marine depositional environment just above the storm wave base, with a supposed depth of 20 m, within the photic zone. The nutrient regime was at least a mesotrophic. The upper boundary of the Cultrijugatus Beds coincides with the Chote?-Event that strongly affected brachiopods, whereas corals and bryozoans were insensitive to this event.  相似文献   

11.
In North Africa, the ammonoids constitute an important part of the Devonian marine macro-invertebrates. New material has been recently collected in the ‘Argiles de Marhouma’ Formation from several sections located near Béni-Abbès in the Saoura Valley (Ougarta Mountains, Algerian Sahara). Red nodular limestones (i.e., ‘griotte’ facies) characterize this formation rich in ammonoids. The assemblages from the Ouarourout section are composed of Goniatitida and Clymeniida constituting 30 species and 19 genera belonging to 11 families, with Cyrtoclymenia, Erfoudites, Kosmoclymenia, Planitornoceras, Platyclymenia, and Prionoceras, as the most abundant genera. The taxonomic comparison and the biostratigraphic correlations are made by considering the assemblages recorded in the Anti-Atlas of Morocco, which are very close to those observed in Algeria. In the Ouarourout area, the ‘Argiles de Marhouma’ Formation contains middle and late Famennian ammonoid assemblages and three biostratigraphic intervals can be identified: Planitornoceras, Platyclymenia and Medioclymenia.  相似文献   

12.
New thelodont scales from the type section of the Khush-Yeilagh Formation, between Shahrud and Shahpasand(Iran), are described. They are provisionally referred to as Skamolepis sp. and Turinia cf. hutkensis. Together with T. hutkensis from South-East Iran and some undescribed scales from the Givetian of Australia, these specimens are some of the youngest thelodont scales known to date, since they are of Lower Eifelian age.  相似文献   

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14.
The Couderousse Member of the Blacourt Formation in the Banc-Noir quarry, Ferques inlier, Boulonnais (Pas-de-Calais, France) has yielded a tooth plate whose morphology is similar to that of Synthetodus, which is considered a holocephalan. Its histology is made of an outer enameloid-like tissue, and an inner trabecular dentine. Its occlusal surface shows a bean-shaped bulge. This tooth plate was prepared from a limestone that is dated from the Middle–Upper varcus Conodont Zone, that is lower upper Givetian. This limestone has also yielded a Pokorninella bricae–Rothpletzella–Tentaculites assemblage, which is indicative of an environment of the inner to middle marine platform boundary. This specimen appears to be the oldest confirmed holocephalan (‘bradyodont’) tooth plate for which the name Melanodus loonesi nov. gen. et sp. is erected.  相似文献   

15.
Seven Middle Devonian (latest Givetian or earliest Frasnian) gastropod species are described from the quarry of Oetelshofen near Dornap (Bergisches Land, northwestern Rheinisches Schiefergebirge, Germany). New species areMurchisonia dornapica, Araeonema osterholzensis, Plagiothyra isekei andMacrochilina drozdzewski. Additionally, a new subspecies,Euryzone delphinuloides oetelshofensis and aNaticopsis-like species and their typical facial occurrence are discussed. The existence of predation is proved by a bore-hole inMacrochilina drozdzewski; the predator itself is not yet identified with certainty.   相似文献   

16.
Vertebrate fossils of the lower Middle Devonian Mühlenberg Formation from the western Bergisches Land (eastern Rhenish Massif) are described. The placoderms are represented by disarticulated plates of coccosteid arthrodires and the acanthodians by several ischnacanthid jaw bones and aMachaeracanthus finspine. The arthrodires are assigned to a new species; a new genus has to be erected if remains of trunk and head shield remains are conspecific.  相似文献   

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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   

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