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1.
For the first time, fossils of unquestionable eurypterid origin are documented from the renowned Lower Devonian Hunsrück Slate Lagerstätte in southwestern Germany. The gnathobase of a coxal plate and a body segment can be attributed to pterygotid eurypterids, probably to Jaekelopterus rhenaniae. These body parts from the Hunsrück Slate once more confirm the extraordinary large size that could be attained by this Rhenish eurypterid. Based on the usual occurrence in marine–terrestrial transitional facies elsewhere in the Rhenish Devonian, rareness in the Hunsrück Slate, and poor preservation, the Hunsrück Slate pterygotid remains are most probably allochthonous, and eurypterids are considered nongenuine elements of the ‘Hunsrück Slate biota.  相似文献   

2.
Altenglanerpeton schroederi n. sp. is documented by a skeleton preserved in dorsal view from the Altenglan Formation of the Saar?CNahe Basin. The only known species of this new genus has a massive skull that is slightly longer than wide with a more or less triangular outline, without traces of lateral-line canals, with a small round orbit, very wide interorbital region, and the jugal extending far in front of the orbit. The long, undifferentiated trunk region comprises at least 30 lepospondylous presacral vertebrae. The pelvic girdle, hind limbs, and tail are not preserved. The forelimb is small and poorly ossified. The cladogram supports placement of Altenglanerpeton in the Recumbirostra. The new genus seems closest to Tambaroter, the Goniorhynchidae, and Brachystelechidae, with the largest number of morphological similarities shared with the Ostodolepidae, particularly with Micraroter and Pelodosotis.  相似文献   

3.
Nanogomphodon wildi n. gen., n. sp. is based on a tiny lower postcanine tooth from the lower Lettenkeuper (Lower Keuper or Erfurt Formation; Ladinian) of Michelbach an der Bilz (Baden-Württemberg). It represents the first record of a traversodont cynodont from the Middle Triassic of Europe and exhibits a distinctive combination of dental features. Along with recent discoveries of other traversodont taxa from the Upper Triassic of eastern North America,Nanogomphodon indicates the existence of a distinct lineage of these cynodonts in the Northern Hemisphere.   相似文献   

4.
Two recently collected slabs from the Lower Devonian Hunsrück Slate of Bundenbach, Hunsrück region, Germany, with spines of the acanthodianMachaeracanthus hunsrueckianum n. sp. are described. Both are associations of large and small spines and are the first to show groupings of symmetrical pairs; the spines are not homologous with those of other acanthodians. A pair of small spines ofMachaeracanthus peracutus Newberry, 1857 from the Karschheck quarry near Oberkirn, Hunsrück region, Germany, is articulated with the pectoral girdle and is the first such complex to be described. The only spines whichMachaeracanthus appears to have had were a pair of large and small pectoral spines on each side of the body. These spines could have helped to prevent the fish from sinking into the mud while resting on the sea floor.  相似文献   

5.
《Annales de Paléontologie》2017,103(2):141-147
A small bird with a shorebird-like beak and a very long hind toe is described from the Early Eocene of Messel in Germany. Vanolimicola longihallucis, gen. et sp. nov. is one of the few candidate species for a “wading bird” from Messel, that is, a bird that may have foraged along the shoreline of the ancient lake. A few features indicate a relationship to charadriiform birds and Jacanidae (jacanas) in particular, but charadriiform affinities are only weakly supported. In the preserved skeletal elements, V. longihallucis also resembles the taxon Songzia from the Early Eocene of China, which is considered to be a representative of the Ralloidea (rails and allies). A potential biogeographic significance of the new Messel fossil is strengthened by similar fossils from the North American Green River Formation.  相似文献   

6.
A new genus and species of a basal testudinoid turtle of the family “Lindholmemydidae,” Paramongolemys khosatzkyi gen. et sp. nov., is described based on shell material from the Naranbulak Formation (Upper Paleocene) of the Naran Bulak and Khaychin-Ula IE localities (Mongolia). Material of this species includes some specimens previously described as Mongolemys tatarinovi.  相似文献   

7.
From the Silberberg Quarry, type locality of the Silberberg Formation (Martini &Ritzkowski 1968), some planktonic foraminifera are described:Globigerina officinalis Subbotina, Globigerina ouachitaensisHowe &Wallace,G. praebulloides leroyi Blow &Banner, G.praebulloides occlusa Blow &Banner which taxa are here suggested to form intergrading morphotypes within the range of variation of a population dominated byG. officinalis. In addition,G. cf.danvillensis Howe &Wallace is found. The planktonic fauna, together with some elements in the benthonic fauna, suggests a possible correlation with the Danville Landing Member of the Jackson Formation, Louisiana, traditionally ascribed to the Upper Eocene. There is some similarity with European Uppermost Eocene — Lower Oligocene faunas described by various authors. The Silberberg Formation was suggested to be a Neostratotype for the Latdorfian Stage of the Lower Oligocene byMartini &Ritzkowski (1968). It is suggested that the Silberberg Formation may well be coeval with the Upper Priabonian as proposed byCita 1969.  相似文献   

8.
《Mycoscience》2014,55(2):108-112
Powdery mildew Phyllactinia (Ovulariopsis cf. insolita) is reported on Funastrum clausum and Fcynanchoides in Sinaloa, Mexico. The fungus was reported as Oidium insolitum on Lycium chilense in Argentina, later as Phyllactinia chubutiana (anamorph Ovulariopsis insolita). This fungus was studied by light microscopy and molecular techniques. Fungal mycelium was smooth, effuse, with septate hyphae; appressoria distinct, or ramified; conidiophores pseudoidium type; mature conidium cingulum-like, subcylindric with sub-apical and sub-terminal protuberances. Two rDNA ITS nucleotide sequences were 99% homolog with P. chubutiana's sequence.  相似文献   

9.
Summary The Carboniferous of N?tsch (Austria), divided into Erlachgraben, Badstub and N?tsch Formations, is composed of a thick sequence of dominantly siliciclastic deepsea sediments. Intercalated marly and silty limestones in the upper Erlachgraben Formation consist of bioclastic wackestones and algal wackestones/packstones which contain a diverse fossil assemblage of formainifers, algae and pseudo-algae. These microfossils are accurately described and documented, and three species of algae are established:Principia fluegeli n. sp.,Paraepimastopora noetschensis n. sp., andNanopora pseudofragilissima n. sp. Based on the occurrence of both important species of the foraminifers Lasiodiscoidea (Howchinia gibba andEolasiodiscus dilatatus), and also on the presence ofEndothyranopsis plana, of the lastEarlandia ex. gr.vulgaris and of the firstEostaffella exp gr.postmosquensis, the upper Erlachgraben Formation is dated as late Serpukhovian (goniatite biozone E 2 of the Namurian A; Arnsbergian stage, corresponding to the Zapaltyubinsky of the standard Russian sequence; foraminiferal biozones 18 or Cf 7 of Belgium, or Cf 16 of the Donbass). Compared to the Pyrenees and the Donbass region, the algal flora of the Carboniferous of N?tsch seems to be relatively endemic. Algae and foraminifers originally inhabited a shallow carbonate ramp and were transported and redeposited in a deep-water environment by gravity flows. The formainifers most probably migrated from the Donbass region along the shelf of a narrow seaway to N?tsch.  相似文献   

10.
Two specimens of Valenciennea helsdingenii (Bleeker, 1858) were collected off Punnakayal coast, from Gulf of Mannar, southeast coast of India in November 2012. The morphometric and meristic characters of the recorded specimens are described and discussed. This is the first record of the species from the Indian waters that is a range extension of its known range within the Indian Ocean.  相似文献   

11.
Summary Anin situ Oxfordian patch reef from the Süntel hills (florigemma-Bank, Korallenoolith, NW-Germany) is described. It is composed of an autochthonous reef core overlain by a ‘parautochthonous’ biostrome. The exposed reefal area amounts to about 20 m in lateral and up to 4 m in vertical direction. Nearly all major marine reefal fossil associations from the Tethyal realm are present. In the reef core two facies can be distinguished: (1)Thamnasteria dendroidea thicket facies and (2) thrombolite facies. The first facies is composed of a thin branched autochthonous coral thicket mainly constructed ofTh. dendroidea colonies with only a minor portion ofStylosmilia. Frequently, theTh. dendroidea branches laterally coalesce bridge-like forming a delicate initial framework which was subsequently reinforced by thick microbial coatings, that make up approximately 80% of the rock volume. This facies is an excellent example for microbialite binding in reefal architecture. Additionally, several generations of micromorphic and partly cryptic encrusting organisms settled on theTh. dendroidea branches and microbialite crusts. They successively overgrow each other and fill the space between the coral branches in the thicket forming a characteristic community replacement sequence. Initial colonization of theThamnasteria dendroidea took place on an oncoidic/bioclastic hardground. During this early phase of reefal development, microbialites also played an important role in stabilizing and binding the reef body. The thrombolite facies (2) occupying nearly the same volume of the reef body as facies type (1) consists of a thrombolitic microbialitic limestone which fills the interstice between the coral colonies. It shows a considerably lower faunal diversity than theTh. dendroidea facies. Numerous cavities are interspersed in the thrombolithe and are almost completely filled with dolomitized allomicrite. In contrast, microbialite and allomicrite adjacent to the reef core rarely reveal any dolomitized areas. Above the reef core, mostly toppledSolenopora jurassica thalli occur together with a few massiveIsastrea colonies forming a parautochthnous biostrome. They are inhabited by a low diverse assemblage of encrusting organisms. Microbialites are only rarely present in this biostromal unit. The patch reef is developed within a lagoonal limemud facies both separated by a sharp interface. In contrast, continuous facies transition exists between theSolenopora biostrome and adjacent deposits which are characterized by micritic to pelmicritic limestone sometimes with lenses of oncoids. Debris derived from the patch reef is only sporadically intercalated in the reef surrounding lagoonal sediments. Gastropods, bivalves, and dasycladalean algae dominate the lagoonal biota. Up-section following theSolenopora biostrome nerinean gastropods become the most abundant species amounting to a ‘Nerinea-bed’. This horizon moderately elevates above the patch reef indicating, that is arose above the surrounding sea floor forming a relief. The patch reef established on a secondary hardground probably released by a minor transgression and a nondepositional regime. It grew up on a well-illuminated sea floor only a few meters below sea level. Only a low background sedimentation rate and modest water circulation are assumed during reefal growth. These features characterize an open marine lagoon. A subsequent shallowing upwards trend caused emergence of the early lithifiedflorigemma-Bank sediments. In the following erosional phase the reef core,Solenopora biostrome and ‘Nerinea-bed’ were sharply cut. Paleokarst phenomena (karst solution of the rocks, selective leaching of the aragonitic corals) truncate the surface of theflorigemma-Bank. Released by a transgressive sea level, the paleokarst surface is densely inhabited by marine boring and encrusting organisms (oysters, serpulids). Karst cavities are filled with an oncoid-bearing bioclastic limestone with a large portion of siliciclastics. Theflorigemma-Bank is overlain by the reddish bioclastic sandstone of the ‘Zwischenfl?zregion’.  相似文献   

12.
The first and presently only record of a ponyfish is described from the Lower Oligocene of the Grube Unterfeld (“Frauenweiler”) clay pit at Rauenberg (S Germany) and compared with other extant and fossil representatives of the Leiognathidae. It differs from all extant (and probably also fossil) members of this family in the coalescence of the ascending and articular processes of the premaxilla and the presence of a straight maxilla with a prominent dorsal crest. It furthermore differs from most extant and probably also fossil Leiognathidae in the combination of the following characters: the presence of multiple-rowed villiform teeth on the oral jaws; the presence of three supraneurals; third and fourth dorsal as well as third anal fin spines that are smooth at their anterior margins; delicate longitudinal surface striations on the neural and haemal spines of the vertebral column as well as on the dorsal and anal fin pterygiophores and on the dorsal, anal and pelvic fin spines; small but not plate-like distal expansions on the dorsal and haemal spines of the fourth preural centrum; the presence of autogenous hypurals; and a squamation that extends anteriorly onto the occipital and otic regions but not onto the cheeks. In terms of its general morphological traits, it resembles Leiognathoides altapinna, a species that has been reported from contemporary localities in Switzerland and Russia, although there are also some deviations that may be indicative of a different species. However, with the available materials, it is difficult to decide whether these differences are of taxonomic significance, so the new record is assigned to the genus Leiognathoides as cf. L. altapinna. The Oligocene specimens from France as well as the Lower Miocene specimens from the Czech Republic clearly belong to different taxa and probably not to the genus Leiognathoides at all. With regard to the palaeoecological and palaeogeographical framework, the new record indicates a tropical to subtropical climate and a waterway connection with the eastern Paratethys.  相似文献   

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15.
A small tube-dwelling organism is interpreted as living in the sediment. This life habit is inferred from the difference between lined burrows and tubes and between soft and rigid tubes. Lamellar extensions of the body-wall may have provided irrigation for the vermiform part of the body. The gaping aperture lacks an operculum and may have been open permanently; the apertural rim was strengthened by spicules. The specimen lacks segmentation and is thus not an annelid worm. Considering the theoretical suitability of the crinoid “forest” in the Hunsrück sea for such worms, the absence of Annelida is curious.  相似文献   

16.
The author recently discovered among 16 discinid brachiopods from the Lower Devonian Hunsrück Slate, by using the X-ray technique, two specimens with mineralized soft parts and pedicle. These are truly unique finds, as previously no bodily preserved pedicle of fossil discinids has been described. Also, they prove that in the Hunsriick Slate soft parts can be pyritized. New shell observations give rise to doubts on the generic assignment ofOrbiculoidea mediorhenana Fuchs 1915. By comparing the anatomy of the related, livingLingula with the extinct discinid in question, a reconstruction of the latter is presented.  相似文献   

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20.
A detailed assessment of postcranial fossils collected at Balouk Keui (Thrace, Greece) in the mid-19th Century by the naturalist Auguste Viquesnel enabled us to identify the material as pertaining to Palaeotherium sp., cf. P. magnum, which constitutes the easternmost occurrence of the genus during the Eocene. We have constrained the geographic and stratigraphic provenance of the fossil by reassessing information about Viquesnel's itinerary and observations. Although the exact age of the fossil remains uncertain, the occurrence of a palaeothere in the Thrace Basin during the Eocene indicates a wider geographic distribution for the genus, which had previously been restricted to western and central Europe. The palaeothere of Balouk Keui confirms that the palaeogeographic range of this group included the Balkans during the middle–late Eocene. This discovery also shows that at least intermittent land connections between western Europe, Southeast Asia, and perhaps Central Iran facilitated mammalian dispersal during the middle–late Eocene, before the famous Grande Coupure.  相似文献   

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