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1.
The Lower Permian in the central Southern Alps yields an important low-diversity fossil assemblage which was deposited in a varied continental setting, showing mainly alluvial fan to lacustrine and, locally, playa-like floodplain environments. The present study is not taxonomical and its objective is to make a first report of new invertebrate organisms and trackways discovered in the Orobic and Collio basins. Such a fossil record, which comprises freshwater jellyfishes, arthropod tracks, stromatolites, algae and other organisms, will further our knowledge about the local and regional geological history of the central-western Southern Alps and improve our understanding of Early Permian palaeoenvironments. On the whole, in both intramontane basins the ichnodiversity and fossil content decreases from a stratigraphic lower portion, mainly lacustrine and alluvial, towards an upper one, characterised by coarse alluvial deposits to floodplain fines. On the basis of both the already known palaeontological data from the two basins, mainly macroflora and tetrapod footprint associations, and the recently discovered taxa, we tried to make reliable palaeoenvironmental inferences and, possibly, hypothesise on a climatic change, which could have occurred during the Early Permian. 相似文献
2.
Lacertoid footprints are the largest component of the Upper Permian Arenaria di Val Gardena Formation ichnofauna that contains hundreds of specimens mostly referred to the ichnogenus Rhynchosauroides Maidwell 1911. In this paper, we analyzed unpublished material and re-examined the Rhynchosauroides footprints of that ichnofauna, in particular the figured specimens. Analysis of Rhynchosauroides and its type ichnospecies R. rectipes Maidwell 1911 was first necessary. This preliminary investigation highlighted several problems, including ichnospecies named on the basis of poorly preserved material and in some cases significantly different from the type ichnospecies. The study allowed for recognition of three ichnotaxa referred to Rhynchosauroides: Rhynchosauroides pallinii Conti et al., 1977, Rhynchosauroides isp.1 and Rhynchosauroides isp.2 and Ganasauripus ladinus igen. et isp. nov. Other material previously referred to Rhynchosauroides is herein regarded as unclassifiable, in the light of present ichnological knowledge and procedures. 相似文献
3.
内蒙古乌达地区早二叠世晋囊蕨属一新种 总被引:3,自引:0,他引:3
通过扫描电镜研究,建立了内蒙古中部乌达地区下二叠统山西组晋囊蕨诉一个新种Chansitheca wudaensis sp .onv.。新种的小心片Sphenopteris型,囊群椭圆形,由4~10个孢子囊组成,着生一示羽片背面,位于中脉的两侧。环带横列于孢子囊的上部,完全,单排细胞,细胞数目约为18个,这些特征表明新种属于里白科。 相似文献
4.
Dr. sc. Heinz W. Kozur Univ.-Doz. Dr. Karl Krainer Univ.-Prof. Dr. Helfried Mostler 《Facies》1996,34(1):123-150
Summary Diverse and abundant trace fossils of the deep-waterNereites ichnofacies have been found in well-dated Early Permian deep-water turbidites (Lercara Formation) of western Sicily (Italy).
Conodonts indicate a latest Artinskian to Cathedralian (late Early Permian) age. Microfossils (pelagic conodonts, albaillellid
Radiolaria, paleopsychrospheric ostracods, foraminiferal associations dominated byBathysiphon), trace fossils (deep-bathyal to abyssalNereites ichnofacies) and sedimentologic data collectively indicate a deep-water environment for the Early Permian turbidites of the
Lercara Formation. The dominance ofAgrichnium and of thePaleodictyon subichnogeneraSquamodictyon andMegadictyon suggests that this icnofauna is closely related in ichnotaxonomic composition to other late Paleozoic deep-water ichnofaunas.
The occurrence ofAcanthorhaphe. Dendrotichnium andHelicoraphe, to date only reported from Cretaceous or Tertiary flysch deposits, suggests that the entire ichnofauna corresponds well
to previously documented Silurian-Tertiary flysch ichnofaunas. Eight new ichnospecies and a new ichnosubgenus,Megadictyon, are described. 相似文献
5.
S. V. Naugolnykh 《Paleontological Journal》2008,42(5):544-553
New taxa of detached seeds are described from the Kungurian (Lower Permian) of the Middle Cis-Urals: Laevigatospermum compressum gen. et sp. nov., Hirsutospermum paniculatum gen. et sp. nov., Rugosospermum callosum gen. et sp. nov., and Craspedosperma filiferum sp. nov. The systematic position of the new taxa is discussed. 相似文献
6.
Lower Permian Bryozoan fauna of Jamal Formation, exposed in Bagh-e Vang (Shotori Mountains, northeast Iran) includes six species.
Three species – Streblotrypa (Streblascopora) marmionensis (Etheridge 1926), Rhabdomeson bispinosum (Crockford 1944) and Alternifenestella kungurensis (Stuckenberg 1898) – indicate the Lower Permian (Artinskian to Kungurian) age of the formation. Three additional taxa – Fistulipora sp. 1, Fistulipora sp. 2 and undetermined timanodictyid bryozoan ?Timanodictya sp. could not be identified at the species level. The investigated fauna refers to Uralian and Australian palaeobiogeographic
provinces. 相似文献
7.
Fossilised traces of swimming amphibians, assigned to Batrachichnus delicatulus and Serpentichnus robledoensis igen. et isp. nov., are described from the Lower Permian of the Robledo Mountains, southern New Mexico. The B. delicatulus specimen is interpreted as a trackway of a small 'amphibian' (temnospondyl, nectridean, microsaur or juvenile embolomere) swimming straight ahead. S. robledoensis consists of repeated pes imprints separated by discontinuous, L-shaped imprints (body traces). It is interpreted as a trackway of an 'amphibian' swimming in a similar manner to the motion of a side-winding snake. The producer of S. robledoensis is more distinctive than in B. delicatulus , and is suggestive of the lysorophian Brachydectes . This is the first locomotory trace to be assigned to this 'amphibian' group. 相似文献
8.
Yu. A. Arendt 《Paleontological Journal》2007,41(1):61-68
New Catillocrinidae Allocatillocrinus rarus sp. nov., with a previously unknown tegmenal structure, Paracatillocrinus shamovi sp. nov., and P. shakhtauensis sp. nov., with an unusual relative position of the crown and stem are described from the Artinskian Stage (Lower Permian) of the western slope of the Middle and Southern Ural Mountains (Boets, Krasnoufimsk, and Shakh-Tau localities). The genus Allocatillocrinus has not previously been recorded from the Permian, while Paracatillocrinus has only previously been reported from the Upper Permian of Timor Island. 相似文献
9.
Seven bryozoan species belonging to the Order Rhabdomesida and Order Cystoporida are described from the Permian deposits exposed near the small town of Deh-e Mohammad, Shotori Mountains (northeastern Iran): Rhabdomeson cf. consimile Bassler, Pamirella nitida Gorjunova, Clausotrypa conferta Bassler, Streblotrypa (Streblotrypa) elegans Sakagami, Streblotrypa (Streblascopora) supernodata nov. sp., Cystodictya sp., and Filiramoporina cf. kretaphilia Fry and Cuffey. The described fauna identifies the age of the Jamal Formation at the locality near Deh-e Mohammad as Lower Permian. It displays palaeobiogeographic connections to the Lower Permian of Pamir (Tajikistan), Indonesia, Thailand and Kansas (North America). 相似文献
10.
In the Eastern Southern Alps of northern Italy (Carnic Prealps, Friuli region), the shallow-water carbonate platform deposits
of the Dolomia Principale Fm. (Norian–Rhaetian, Upper Triassic) show best-preserved platform to basin facies transition. The
palaeontological study of an algal-rich level recovered from the platform margin facies (Mt. Pramaggiore) has displayed a
very interesting association of Dasycladales. Two new genera (Bystrickyella and Elliottporella) and four new species (Bystrickyella ottii, Elliottporella morelloae, Palaeodasycladus lorigae and Holosporella conradii) have been described. These new data suggest that the Norian represents a period of turnover in the evolutionary history
of the green algae community. This stage, placed between two extinctions, end-Ladinian and end-Norian, is here interpreted
as a re-organization period of the evolutionary schemes of Dasycladales. The new lineages originated in the Norian developed
further and characterized the Early Jurassic scenery.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
11.
A new species of Discinites is described from the Late Permian Upper Shihhotse Formation of the Weibei Coalfield, Shaanxi Province, China. D. hanchengensis sp. nov. has decurrent and disk-like sporophylls with deep-toothed apices, elliptical sporangia and rectangular epidermal cells. The spores are generally of the Calamospora type. The megaspores and microspores are 300–380 and 45–90 μm in diameter, respectively. The microspores are similar in size to those of all other species of Discinites that contain Calamospora, but the megaspores are remarkably smaller. The new species represents the first record of Discinites with Calamospora from China and from the Cathaysian flora. Finally, we summarize the associated foliages of Discinites in the Cathaysian flora and find that they are all markedly different from those found in the Euramerican flora. 相似文献
12.
13.
SANDRA E. K. SEQUEIRA 《Zoological Journal of the Linnean Society》1998,122(1-2):237-259
Five saurerpetontid temnospondyl amphibian specimens from the Lower Permian Arroyo Formation of Baylor County, Texas are redescribed under the binomenIsodectes obtususcomb. nov.The material includes the types ofIsodectes megalopsCope,Trimerorhachis conangulusCope,Acheloma?caseiBroili andEobrachyops townendaeWatson. The Arroyo Formation saurerpetontid is indistinguishable from that from the Middle Pennsylvanian of Linton, Ohio, previously known asSaurerpeton obtusumand the two taxa are synonymized here. The Saurerpetontidae is a monophyletic family comprising the generaIsodectesandAcroplousand defined by reduced strip-like tabulars, dorsal exposure of the palatine excluding lacrimal from orbit margin, parasphenoid with «winged» basal plate, rectangular dermal plates bordering medial margin of mandible, and ilium with elongate dorsal blade. Some of the resemblances described by Watson between «Eobrachyops townendae» and the later brachyopid temnospondyls appear to be artefacts of crushing of an individual specimen, and the relationship between the Saurerpetontidae and Brachyopidae requires reconsideration. 相似文献
14.
Summary A rich and diverse dasycladalean algae association is described from the Upper Triassic succession of Mt. Rotonda (Calabria-Lucania
border, Southern Italy).
This association consists of:Neoteutloporella rajkae n.sp.,Griphoporella bechst?dti n.sp.,Physoporella zamparelliae n.sp.,Spinaporella andalusica
Flügel & Flügel-Kahler, 1984,S.? granadaensis
Flügel & Flügel-Kahler, 1984,Chinianella? sp.,Gyroporella sp.,Griphoporella? sp. andPhysoporella aff.leptotheca.
Neoteutloporella rajkae n.sp. is characterised by an undulated calcareous skeleton with short acrophore primary laterals bearing a tuft of 4–6 elongate,
segmented, trichophore secondary laterals. This species allows to extend back to the Upper Triassic the stratigraphic range
of the genusNeoteutloporella, previously known only from Upper Jurassic levels.
Griphoporella bechst?dti n.sp. has a cylindrical calcareous skeleton and primary laterals only, consisting of a thin proximal part followed by a swollen
portion that pinches out distally and finally opens outward with a cup-like swelling.
Physoporella zamparelliae n.sp. is characterised by a calcareous skeleton made by partly welded thin individual sheaths enclosing the laterals. The
laterals are piriferous, vertically compressed, roughly triangular both in vertical and in verticillar section. In some specimens
they end with a spine-like thin apophysis. This species confirms that the typical Middle Triassic genusPhysoporella survived up into the Norian.
The dasycladalean algal association of the Norian of Mt. Rotonda shows some similarities with the algal association found
in the Upper Triassic of the Betic Cordillera whereas it is markedly different from the rich association occurring in the
Upper Triassic of Sicily and of the Northern Calcareous Alps. This pattern is coupled with a different composition of the
platform margin communities: microbial/serpulids bioconstructions in the Upper Triassic of the Calabria-Lucania border and
of Alpujarridevs. Dachstein-type reefs in Sicily and the Northern Calcareous Alps.
This indicates that the palaeoceanographic and palaeogeographic conditions controlled both the development of the different
platform margin and of the different algal assemblages. 相似文献
15.
Here we discuss the duration and position of Upper Rotliegend and Zechstein stratigraphic units in relation to the absolute time scale, and reinterpret a carbon isotope (δ13C) global event recorded from Late Permian (Lopingian/Guadalupian) marine deposits. Based on δ13C isotope correlation (chemostratigraphy) and of climatic evidence related to the end-Guadalupian global marine and terrestrial crisis, the Guadalupian/Lopingian boundary is proposed as the boundary between both the European Upper Rotliegend (URII)/Zechstein sediments and the parallel south-west USA Ochoan/Bell Canyon Formation units. The Zechstein deposition was strongly influenced by climatic oscillations, and the marine ingressions recorded in the North German Basin and North American Delaware Basin are presumed to have resulted from the same eustatic sea-level changes in western and northern coasts of the Northern Pangaea Supercontinent. Existing constraints on the age of the Upper Rotliegend II (UR II) deposits are imposed by the uncertainty of the chronostratigraphic boundary of the Kupferschiefer and by a time marker that is Illawarra, the boundary of the reversed polarity megachron (Kiaman) and mixed polarity megachron. Three options (A, B, C) have been discussed, which are connected with a time span comprising deposition of the UR II rocks, assuming that the time span needed for the Dethlingen/Lower Noteć formations and Hannover/Upper Noteć formations is about 6 myr. The time left for the deposition of the Parchim/Lower Drawa, Mirow/Upper Drawa deposits and the time hidden in the erosional gaps and hiatuses range from 1.6 myr to 4 myr or even 8 myr. These were based on the time interval related to the Kiaman Reversed Polarity megachron, which can contain more transient normal polarity zones than currently accepted. The presence and absolute dating of all such magnetozones is difficult to determine because they are represented in continental strata characterized by numerous, poorly time-constrained erosional gaps. The proposed option C is provisionally integrated with magnetostratigraphic results and shows an alternative stratigraphical scheme for the Upper Rotliegend. This alternate Upper Rotliegend stratigraphy helps correlate rocks (deposited in dry arid climatic conditions) in the lower part of the Upper Rotliegend II of the Southern Permian Basin (Havel and Drawa subgroups) with similar rocks in the Delaware Basin (attributed to formations within the Leonardian Regional Series). 相似文献
16.
Studies on Early Permian tetrapod ichnofauna emphasized the scarcity of forms from Italian sites. A revision work on the entire collections revealed the presence of Hyloidichnus bifurcatus Gilmore, 1927 and Limnopus heterodactylus (King, 1845). The ichnoassociation now lists seven ichnogenera: Amphisauropus, Batrachichnus, Dromopus, Erpetopus, Hyloidichnus, Limnopus, Varanopus. These new data enlarge the ichnoceonosis, adding tracks of medium-size captorhinomorphs (Hyloidichnus) and temnospondyls (Limnopus) to the Italian ichnofauna, previously characterized by scarcity of predators and amphibians. Radiometric ages give a strong age constraint to the ichnoassociation (Early Kungurian), allowing useful correlations to contemporary successions all over the world. The main difference is the absence of Ichniotherium and Dimetropus, and this could have a stratigraphic or paleoenvironmental significance. The fauna is similar in two main basins, Collio and Orobic. It differs solely in the proportions between ichnotaxa, with a predominance of areoscelid traces (Dromopus) in the Collio Basin and of captorhinomorph traces (Erpetopus, Varanopus, Hyloidichnus) in the Orobic Basin. This datum could reflect slightly different environments, seasonal in the Collio Basin (alluvial plain) and more arid in the Orobic Basin (playa-like). The lack of some forms in smaller basins of the Athesian Volcanic Complex is probably due to a bias. 相似文献
17.
2006年在秦岭西麓林区,观察到4个勺鸡巢呈典型的深碗形,开口向上,圆形或近圆形,巢深8.60±0.33cm,巢口外径为21.50±0.41cm,巢口内径为14.75±0.96cm,巢材厚度为2.5~4.0cm。巢材质主要由枯叶、枯草及勺鸡自身掉落的羽毛构成。勺鸡卵近似椭球体,卵壳呈淡黄色,并伴有紫褐色斑点,平均长径为49.85±2.48mm;平均短径为36.00±1.41mm;窝卵数4~6枚。在秦岭西部山区,勺鸡喜欢选择栖息于1861~2100m之间的阔叶林或针阔混交林生境。由于森林的过度开发与人为捕猎,勺鸡野外生存状况不容乐观,亟需制定有效的措施加以保护。 相似文献
18.
The cave bear evolution is characterized by some specific trends, including the increase in size, the progressive complication of the tooth surface and the gradual strengthening of the metapodial bones. Important indicators of the evolutionary level are the morphodynamic index of P4/4 and the plumpness index of the metapodial bones. Only recently, the morphological and morphometric analysis was complemented by genetic analysis – particularly of mtDNA. As a consequence, mainly based on genetics, new taxa have been proposed, for some of whom the exact taxonomic rank (species or subspecies?) is still under discussion. However, the new evolutionary model presents some problems because the genetic data alone are not sufficient to ensure a specific distinction and the morphodynamic and morphometric data do not support a specific distinction between the cave bear populations. The morphometric analysis performed on numerous metapodial bones belonging to some Italian (Buco dell’Orso, Covoli Velo and S. Donà di Lamon) and European populations seems to confirm, on the whole, a level of diversity not higher than that of a subspecies, allowing at most the identification of some local evolutionary trends, as assumed for the populations which have been living in the Italian peninsula. 相似文献
19.
Excavations at hearth levels at the Molare Shelter in 1985 yielded the mandible of a 3-4-year-old child. The associated lithic artifacts recovered with it are Mousterian. Its features, although quite archaic, are within the known range of variation of Neandertals. Four deciduous molars are still preserved in the mandible. They were compared with other known specimens, which date to the Middle and Upper Pleistocene. The metrical characteristics are surprisingly primitive, within the range of variation of Homo erectus, or at least within that of European Pre-Neandertals, more so than within the variability of typical Neandertal specimens. On the other hand, the morphological characteristics, except for a few that are decidedly plesiomorph, are predominantly Neandertal. 相似文献
20.
Hieracium pallidum subsp. aetnense Gottschl., Raimondo & Di Grist. is described and illustrated. H.pallidum is considered as an intermediate species between H. schmidtii and H. racemosum (“schmidtii>racemosum”) and is placed in H. sect. Grovesiana. By consequence, H.lanudae Gottschl. is transferred to H. pallidum as H. pallidum subsp. lanudae (Gottschl.) Gottschl., Raimondo & Di Grist. A key for the three recognised subspecies of H. pallidum is provided. 相似文献