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1.
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   

2.
《Palaeoworld》2015,24(4):454-459
The extensive Devonian marine deposits of South China have yielded few articulated crinoid cups or theca. Two Eifelian specimens, from the Gupa Member, are the first ones reported from the Yingtang Formation, Eifelian, from the Ma’anshan section, Guangxi, South China. The new taxon Guangxicrinus xiangzhouensis n. gen. n. sp. is the first report of a marsupiocrinid in China, extending the paleogeographic range of the family into the Paleotethys and the stratigraphic range of the family upward from the upper Silurian into the lower Middle Devonian, Eifelian. The occurrence of Halocrinites sp. is the third occurrence of a cupressocrinitid in China and extends the paleogeographic range from Yunnan to Guangxi.  相似文献   

3.
JAN BOHATÝ 《Palaeontology》2011,54(5):1177-1197
Abstract: The discovery of new specimens and the restudy of known collections result in revision of the diagnosis and the stratigraphic distribution of the disparid crinoid genus Stylocrinus, from the Middle and Upper Devonian of Europe, Asia and Australia. The consistent development of three basal plates, the atomous arms with internally inclined edges adjoining laterally with adjacent brachials in an interlocking network and an apparently rudimentary pinnulation is recognised. The high ecophenotypic plasticity of the common species S. tabulatus negates the validity of several former subspecies and demonstrates the general morphologic variability of the aboral cup proportions. This contrasts with the low morphological spectrum of rarer stylocrinid species. With exclusion of ‘S. elimatus’ (Silurian) from Stylocrinus, the genus is limited to the Devonian. A neotype is proposed for the lost holotype of S. tabulatus. Stylocrinus prescheri sp. nov. is described from the Eifelian to Givetian of Europe and Asia. The first evidence of the gastropod grazing trace fossil Radulichnus on a crinoid aboral cup (S. tabulatus), the post‐mortem incurred ossicular‐boring of radial and basal plates as well as the post‐mortem encrusting by a rugose coral are further observations on Stylocrinus aboral cups.  相似文献   

4.
A juvenile cup, disarticulated arm plates, and columnals of the crinoid Arachnocrinus sarizensis n. sp. are described from the Eastern Taurus Mountains of central Turkey. This is the first Paleozoic crinoid based on a cup and arm plates reported from Turkey. Suggested revision of the Gasterocomidae includes transfer of Arachnocrinus and Ancyrocrinus to the family and rejection of Kopficrinus from the family. The stratigraphic range of Arachnocrinus is extended upward into the Middle Devonian from the Early Devonian. The Devonian of Turkey is of special interest because it includes Laurasian and Gondwanan components on different tectonic blocks. The paleogeographic range of Arachnocrinus is extended from the North American plate onto the Anatolian block, which would have been located on the southern edge of the Paleotethys Sea in the Middle Devonian in a shelf basin off the northern coast of Gondwana at approximately 42° south latitude.  相似文献   

5.
The Early/Middle Miocene (European Land Mammal Zone MN5) localities of Sandelzhausen and Rothenstein 13 in southern Germany have yielded remains of about 13 ophidian taxa: Eoanilius sp. (Aniliidae), Bavarioboa ultima (Boidae), “Coluber” sp., ?Telescopus sp., Natrix sp., cf. Natrix sp., cf. “Neonatrix” sp., unidentified “colubrines” and “natricines” (Colubridae), Naja sp., an unidentified elapid (Elapidae), Vipera sp. (“Oriental viper”), Vipera sp. (“aspis complex”) (Viperidae). Both faunas document a transitional phase from those reported from several late Early and Middle Miocene sites of Central and Western Europe. The climates of Sandelzhausen and Rothenstein 13, as indicated by ophidian fossils, were warm, although not tropical or subtropical.  相似文献   

6.
The generic diagnosis of the Mid–Late Devonian zosterophyll Serrulacaulis Hueber and Banks is emended based on morphological study on specimens from New York State (USA), Belgium and Venezuela, and new materials of S. spineus n. sp. from the Middle Devonian Hujiersite Formation of Xinjiang, Northwest China. The new species S. spineus has bilateral obdeltoid emergences and sparsely arranged spines on the axis surface, alternately arranged, reniform sporangia with unequal valves. A variety of the axial emergence appearances of Serrulacaulis is noted, which further indicates easily recognizable features of the genus.  相似文献   

7.
New coelenterate taxa of the subclass Rugosa from the Middle Devonian of the western slope of the Subpolar Urals, the genus Syvjuphyllum (with the type species S. sokolovi gen. et sp. nov.) and the species Cosjuvia yushkini sp. nov., are described.  相似文献   

8.
In 1930W.E. Schmidt described all known crinoids from the German Early Carboniferous, including the Etroeungt beds of Germany, which are now judged to be latest Devonian (Famennian) in age. On a global basis, Famennian camerate crinoids generally show a closer relationship to succeeding Early Carboniferous faunas than they do to older Frasnian or Middle Devonian crinoids, which also is the case for the Strunian fauna. Holdovers from older Devonian faunas include, among others,Adelocrinus, a descendant of olderArthroacantha, in England and Germany, andPetaloblastus, which is one of the youngest genera of the blastoid family Hyperoblastidae. Precursors of younger Early Carboniferous groups include platycrinoids, primitive actinocrinoids, dichocrinoids, and the blastoid genusDoryblastus, which is one of the oldest members of the family Orbitremitidae. All of these groups, which became important parts of the Early Carboniferous crinoid and blastoid radiation, give Famennian crinoid faunas much more of an Early Carboniferous than a Devonian aspect. Rhipidocrinus schmidti n. sp. is erected for specimens that originally were reported from the Etroeungt asRhodocrinus uniarticulatus. We judge that there are currently four valid species assigned toRhipidocrinus: R. crenatus, R. perloricatus, R. praecursor, and our new species,R. schmidti. Hydriocrinus ratingensis Schmidt is reassigned to ?Sostronocrinus. We note thatSchmidt (1906), notJaekel (1906) as has been reported previously, is the author ofRhipidocrinus perloricatus. Owing to the poor preservation of the Etroeungt material, we regard the namePlatycrinites wunstorfi Schmidt 1930 to be a nomen nudum.  相似文献   

9.
For a long time, the highly aberrant crinoid Scoliocrinus was known only from the Lower Givetian Eifel area (western Rhenish Massif) as a single oblique calyx with only two out of five radials having an arm facet. Several almost complete crowns of a new species in the Middle Givetian Finnentrop area (eastern Rhenish Massif) have two fan-like arms (in the A and E rays), and a horizontal large anal tube. The probable mode of life of Scoliocrinus is analysed by (a) functional morphology mainly of the arms, (b) criteria of minimised faecal recycling, (c) biostratinomic association with two new species of another aberrant, but four-armed new crinoid genus thus suggesting original syntopy with Scoliocrinus. It is concluded that the construction of Scoliocrinus is probably an adaptation to prevailing unidirectional (tidal?) currents in biostromal reef biotopes. This is supported by rather similar crinoid occurrences in a Lower Givetian biostromal reef-related region in the western Rhenish Massif, with the genotype of Scoliocrinus and a newly assigned third species of Scoliocrinus (arm and probable part of the calyx), as well as four-armed species. The new forms are described as Scoliocrinus ubaghsi nov. sp., Scoliocrinus gerolsteinensis nov. sp., Trapezocrinus scheeri nov. gen., nov. sp., and Trapezocrinus hilperti nov. gen., nov. sp.  相似文献   

10.
The first calcitic thecas of edrioasteroids from the Rheinisches Schiefergebirge are described:Timeischytes leunisseni n. sp.,Timeischytes prescheri n. sp. andRhenopyrgus sp. are from the Middle Devonian of the Eifel Hills. The morphological features ofTimeischytes lead to the assumption that in this genus paedomorphosis has been a long-lasting process.  相似文献   

11.
《Palaeoworld》2016,25(4):639-646
Additional specimens of rhynchonellide brachiopods from the marly limestones in the Yidade Formation at the Panxi section in eastern Yunnan have been ascribed to the species “Paurorhynchasquamosa Wang, 1956 and “P.depressa Wang, 1956. The two species have been used frequently as index fossils for the Frasnian (Upper Devonian), but their taxonomic assignments are problematic because their internal structures remain unknown. In this study, detailed systematical examinations on both external characters and internal structures revealed by serial sections suggest that the two species are more appropriately assigned to the genus Hadrotatorhynchus Sartenaer, 1986. Based on the stratigraphical distributions of Hadrotatorhynchus and the conodonts in the upper unit of the Yidade Formation, the Hadrotatorhynchus-bearing horizons are re-considered as the uppermost Givetian (Middle Devonian) rather than Frasnian stage, although the precise position of the Middle/Upper Devonian boundary still depends on further investigations of high-resolution biostratigraphy.  相似文献   

12.
From the Early Aptian (“Tæck”) of Heligoland (North Germany) three new species, one new genus and one new family of Teuthids are described:Mastigopbora stuehmeri n. sp.,Boreopeltis helgo landiae n. gen. n. sp. andMaioteuthis damesi n. sp. The new genusBoreopeltis n. gen. ist placed in the family Plesioteuthididae NAEF 1921. The genusMastigopbora OWEN 1856 previously attributed to the family Loligosepiidae van Regteren Altena 1949 is proposed as type genus of the new family Mastigophoridae. Two poorly preserved specimens cannot be identified specifically (?Trachyteuthis sp. andPlesioteuthis sp.).  相似文献   

13.
A new genus and species of rhabdomesine cryptostome bryozoan, Lunostoma pulchra n. gen. n. sp., is described from the Lower Givetian (Middle Devonian) of the Eifel, Germany. It differs from all previously known rhabdomesines in having crescent-shaped structures (??scuta??) on the proximal sides of the apertures. These scuta resemble the lunaria that characterise cystoporate bryozoans, providing yet another example of homeomorphy in the Bryozoa. The function of scuta is unclear as, in contrast to lunaria, they do not project sufficiently from the apertures to constrain the everting lophophores.  相似文献   

14.
The whitefly Bemisia tabaci complex contains many cryptic species, of which the Middle East-Asia Minor 1 (MEAM1) and Mediterranean (MED) are notorious invasive pests. In our field-collected whitefly samples, MEAM1 harbors an obligate primary symbiont “Candidatus Portiera aleyrodidarum” and two secondary symbionts, “Candidatus Hamiltonella defensa” and Rickettsia sp., whereas MED has only “Ca. Portiera aleyrodidarum” and “Ca. Hamiltonella defensa.” Both “Ca. Portiera aleyrodidarum” and “Ca. Hamiltonella defensa” are intracellular endosymbionts residing in the bacteriomes, whereas Rickettsia sp. has a scattered distribution throughout the host body cavity. We examined responses of these symbionts to adverse temperatures as well as survival of the host insects. After cold treatment at 5 or 10 °C or heat treatment at 35 or 40 °C for 24 h, respectively, the infection rates of all symbionts were not significantly decreased based on diagnosis PCR. However, quantitative PCR assays indicated significant reduction of “Ca. Hamiltonella defensa” at 40 °C, and the reduction became greater as the duration increased. Compared with “Ca. Hamiltonella defensa,” “Ca. Portiera aleyrodidarum” was initially less affected in the first day but then showed more rapid reduction at days 3–5. The density of Rickettsia sp. fluctuated but was not reduced significantly at 40 °C. Meanwhile, the mortality rates of the host whiteflies elevated rapidly as the duration of exposure to heat treatment increased. The differential responses of various symbionts to adverse temperatures imply complex interactions among the symbionts inside the same host insect and highlight the importance of taking the whole bacterial community into account in studies of symbioses.  相似文献   

15.
Two new eurypterid species, Adelophthalmus kamyshtensis sp. nov. and Adelophthalmus dubius sp. nov., are described from the Middle Devonian of Khakassia. The new species are among the earliest known members of the genus Adelophthalmus and the earliest members of this genus known outside Europe and North America.  相似文献   

16.
Südkamp (Paläontologische Zeitschrift 81:181–204, 2007: 198; Figs. 15A, B) described and figured the diplobathrid camerate crinoid Acanthocrinus spinosus n. sp. from the lower Devonian Hunsrück Slate of Karschheck quarry near Oberkirn, Rhineland-Palatinate, Germany. However, this name is preoccupied by Rhodocrinus (=Acanthocrinus Goldring 1926) spinosus Hall 1862 and therefore is invalid. A replacement name is proposed as Acanthocrinus multispina nom. nov.  相似文献   

17.
The newly found tetracoralAngustiphyllum cuneiforme n. gen. n. sp. from theGosseletia-Sandstein (Couvinium) of Candás/Prov. Oviedo (Northern Spain) is described and designed an ancestor of the so called “cuneate corals”Homalophyllum Simpson, 1900,Xenocyathellus Bassler, 1937 andHomalophyllites Easton, 1944 from the Devonian and Mississippian of North-America. Because of their undoubtful genetic relations the whole group of cuneate corals is joined to the subfamily Homalophyllidae n. subfam. within the family ZaphrentoididaeSchindewolf, 1938. Evidently the evolution developed in a progressive orthogenetic manner from the new genesAngustiphyllum (Middle Devonian) toXenocyathellus (higher Middle Devonian) andHomalophyllites (Mississippian), whileHomalophyllum (Middle Devonian) separated from this line in a early stage and thenceforth had its own evolution.  相似文献   

18.
HiMag tall fescue (Lolium arundinaceum (Schreb.) S.J. Darbyshire = Festuca arundinacea Schreb) was selected for high Mg concentration in the herbage to reduce grass tetany risk to ruminants; however, the mechanism of increased Mg uptake into shoots is unknown. The objective was to determine cation concentrations of roots, crowns, and leaves in plants of cv. HiMag and its parents, cv. Kentucky 31 and cv. Missouri 96, grown in nutrient solution for 42 days, and determine if cation ratios in roots, crowns, and leaves are different, indicating a difference due to translocation. Treatments were “basal” (1.5 mM K and 0.5 mM Mg), “K” (3.2 mM K), “Mg” (1 mM Mg), and “K?+?Mg” (3.2 mM K and 1 mM Mg). For HiMag, Mg was lower in roots (Trial 2 only), not different in crowns, and greater in leaves than Kentucky 31 and Missouri 96. Doubling the K and Mg of the nutrient solution from basal levels resulted in a 44% reduction of root Mg in Kentucky 31 and Missouri 96, compared to a 17% reduction in root Mg for HiMag. The K inflow rate in HiMag for the basal treatment was lower than that in Kentucky 31 and Missouri 96. These results provide evidence for a process that limits K uptake and an active Mg translocation mechanism in tall fescue. HiMag was apparently selected for traits that promote translocation of Mg from roots to shoots.  相似文献   

19.
Distribution of the Devonian conodont genus Pelekysgnathus is considered. A new species, P. jeppssoni sp. nov. from the Mosolovian Regional Stage (Middle Devonian, Eifelian) of the Voronezh Anteclise is described.  相似文献   

20.
A new pycnosteid species, Schizosteus shkurlatensis sp. nov. (Agnatha, Psammosteiformes), from the Staryi Oskol beds (Givetian, Middle Devonian) of the Voronezh Region is described. This is the first species of the genus Schizosteus Obruchev from the Central Devonian Field. The similarity between species of this genus and early species of Psammolepis is discussed.  相似文献   

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