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1.
Fossil anguine lizard specimens from several Turkish localities are described in this paper. The material comes from ten different localities, spanning a large geographic area consisting of both parts of the European Turkey and Anatolia, and ranging in age from the Oligocene to the Late Miocene. In certain cases, the generic determination was possible and, accordingly, members of Ophisaurus and Anguis were identified and described in detail. The specimens of Anguis, found in different, Middle and Late Miocene localities from Anatolia, represent two of only a few fossil occurrences of this taxon. Moreover, the material reported herein represents the oldest occurrences of anguine lizards, not only from Turkey, but from southeastern Europe and the Eastern Mediterranean basin as a whole. These rare records provide important information about the dispersal routes of anguines from Europe to Asia and significantly enhance our understanding of their biogeography.  相似文献   

2.
New remains of Eremotherium were recovered from the Pacific coast of Ecuador’s Manabi province. The Machalilla fossiliferous locality records the northernmost presence of Eremotherium along the Pacific coast of South America. Most of the fossil remains belong to the same individual, mainly its posterior half, but other individuals are represented. Among the better-preserved specimens are skull fragments, most of the hind limb bones and a number of trunk and caudal centra. These remains were compared with samples collected during the 20th century along the southern coastal regions of Ecuador and northern Peru. Many characters of the long bones and tarsals testify to a possibly different lineage despite the closeness of other Eremotherium populations. Some metric and morphological aspects suggest a different space-temporal southern Caribbean provenance. Other Eremotherium specimens, coming from other Ecuadorian localities, were studied and compared with classic Eremotherium samples. Interesting morpho-functional aspects are pointed out with regard to the tail and its importance in the bipedal stance.  相似文献   

3.
New trilobite material and the first graptolites from outcrop are described from the Am5 member of the Amdeh Formation near Al Fleij in northeast Oman. The sediments in which these faunas occur are interpreted as distal-shelf deposits with storm beds packed with brachiopods and orthoconic nautiloids. The deposits and its faunas are considered of late Darriwilian age and younger than the shallower-water Am5 deposits known from other outcrops. No palynomorphs could be recovered to confirm this due to the increased burial temperature the Al Fleij area has experienced.The trilobites are of considerable palaeo-biogeographic interest as few faunas of this age are known from the Arabian Plate, though their preservation precludes the establishment of new species. They include Isabelinia aff. glabrata, Liomegalaspides sp., Neseuretus tristani, Neseuretinus sp. and the deeper-water forms, Cyclopyge cf. C. bohemica, Arthrorhachis sp. and Brachypleura sp. The graptolites are pendent Didymograptus spp. of later Darriwilian type.Rare elements of the conodonts Nordiora, Amorphognathus and Microzarkodina have been recovered from shell beds that occur interbedded with the faunas. They too indicate a late Darriwilian age and differ from richer, restricted, shallow-water faunas known from the Am5 at other locations, and the more cosmopolitan shelf fauna from the Ayim Member of the Rann Formation of the United Arab Emirates.A coarser, 80 m-thick, terrestrial sequence containing igneous pebbles, included in the Am5 in the 1980s, is shown from the occurrence of fossil plants to be of Permian age and probably equivalent to the Basal Saiq Clastics of Jabal al Akhdar.  相似文献   

4.
New remains of Eremotherium were recovered from the Pacific coast of Ecuador’s Manabi province. The Machalilla fossiliferous locality records the northernmost presence of Eremotherium along the Pacific coast of South America. Most of the fossil remains belong to the same individual, mainly its posterior half, but other individuals are represented. Among the better-preserved specimens are skull fragments, most of the hind limb bones and a number of trunk and caudal centra. These remains were compared with samples collected during the 20th century along the southern coastal regions of Ecuador and northern Peru. Many characters of the long bones and tarsals testify to a possibly different lineage despite the closeness of other Eremotherium populations. Some metric and morphological aspects suggest a different space-temporal southern Caribbean provenance. Other Eremotherium specimens, coming from other Ecuadorian localities, were studied and compared with classic Eremotherium samples. Interesting morpho-functional aspects are pointed out with regard to the tail and its importance in the bipedal stance.  相似文献   

5.
Orthophragminids from the Bartonian Fulra Limestone in Kutch, India and the coeval units in Sulaiman Range in Pakistan suggest the establishment of a significant number of endemic species in the Indian subcontinent (Eastern Tethys). Among a total of fifteen species of Discocyclina, Orbitoclypeus and Asterocyclina, six of them appear to be confined to Indian subcontinent while seven species are common both to the peri-Mediterranean/Europe region (Western Tethys) and Indian subcontinent. Two species, Asterocyclina sireli, a four-ribbed species of possibly Indo-Pacific origin, and Orbitoclypeus haynesi that form large populations in Fulra Limestone, appear to have spread into North Africa and Turkey but not into European platforms as a response to Middle Eocene Climatic Optimum (MECO). The lack of Lutetian and Priabonian fauna in the studied sections, either due to a hiatus or unsuitable depositional environments, hampers the establishment of the actual stratigraphic ranges of the identified taxa. Our record provides us to characterize the orthophragminids in shallow benthic zone (SBZ) 17 for Eastern Tethys in detail by comparing the data from the above localities with those from the North Africa, Europe and Turkey, showing the change in diversity.  相似文献   

6.
In this paper the short snout Cenomanian enchodontids from the El Chango quarry, Chiapas, southeastern Mexico, are reviewed. Unicachichthys multidentata nov. gen. and sp. is named and identified as a new member of the Enchodontidae because it has the predorsal scute series that is the distinctive character of such family. This new genus resembles other short snout enchodontids, as Enchodus and Eurypholis; however, Unicachichthys differs from these and other members of the family because it shows characters ever observed, including a multitoothed dermopalatine, the presence of a basal sclerotic bone, and the serrations in the posterior edge of the preopercle vertical limb. The inclusion of Unicachichthys in two phylogenetic analyses, based on studies previously performed, suggests that this is a primitive representative of the family Enchodontidae. Additionally specimens of two different species of Enchodus from the El Chango quarry are also described; these specimens are so scarce and fragmentary that it is not possible to determine their specific taxonomic identity. The record of these Mexican fossils enrich the knowledge about the diversity of Cenomanian enchodontids in the North American domain of the Tethys Sea, which now contains new taxa that should be considered in future efforts to recognize the phylogenetic and biogeographic processes experienced by this fish group.  相似文献   

7.
Three species from different stratigraphical levels of the Cretaceous of the Helvetic Alps are described. (1) Rhynchonellid specimens from the upper Öhrli-Kalk (Öhrli Formation, Late Berriasian) of NE Switzerland (Alpstein) identified as Lamellaerhynchia heimi (Sulser 2008) [Rhynchonellida, Hemithiridoidea]. Its range appears to be limited to a small area of the carbonate platform of the northern Alpstein chain. Based on internal and external morphological criteria L. heimi differs from other species of Lamellaerhynchia, as well as from Burrirhynchia cf. sayni (Jacob & Fallot 1913), occurring in the younger carbonate platform of the Schrattenkalk Formation (Early Aptian). (2) Recently collected material in various localities of the Altmann Member (Tierwis Formation, Late Hauterivian to Early Barremian) in the Alpstein area identified as Oblongarcula cf. alemannica Owen 1977 [Terebratellidina, Laqueoidea]. This species is closely related or identical to O. alemannica of the North European Boreal province and gives a reference to the occurrence of the genus Oblongarcula in the Tethyan domain of the Alps. Partially silicified specimens enable in rare cases a direct access to internal structures after that they were exposed by an acid treatment. (3) Tulipina koutaisensis (Loriol 1896) [Terebratellidina, Kingenoidea], known from Aptian deposits in the central Caucasus of Georgia, has been recorded as a rare species in the Plattenwald-Bed (Selun Member of the Garschella Formation, Albian) of W Austria (Vorarlberg). The localised occurrence and the temporal gap between the Caucasian and the Helvetic T. koutaisensis suggest an east–west directed migration along the northern margin of the Tethys Ocean during the Early Cretaceous.  相似文献   

8.
Karydomys, a rare genus of cricetid rodents from the Middle Miocene of central Europe, had previously been reported only from the Swiss part of the North Alpine Foreland basin; documented evidence from the German part was lacking. This paper describes several new specimens of Karydomys from the German localities Höll and Laimering 3. A correlation of both localities to the Bavarian local biostratigraphic scale OSM F is proposed. Taxonomically, the fossils are most probably linked to K. wigharti from Hambach 6C (north-west Germany), and thus assigned to K. cf. wigharti. In spite of the scarcity of Karydomys fossils in the Upper Freshwatermolasse, the taxon is an important biostratigraphical marker because of its short stratigraphical range.  相似文献   

9.
Pollen tetrads and monads of spiny pollen grains with close affinities to palms have been found in several localities from the Lower Cretaceous (Barremian-Albian) of the Austral Basin (Magallanes), Patagonia (Argentina). When found dispersed, spiny and zonasulcate pollen grains, are commonly referred to the fossil genus Spinizonocolpites Muller, with close affinities to the extant palm Nypa. The Patagonian specimens were compared with fossil and extant members of the Arecaceae, showing close similarities in shape and sculpture with the primitive members of the subfamily Calamoideae. Nypa produces tetragonal tetrads different from the tetrahedral tetrads of the Spinizonocolpites-type recovered from Patagonia. The specimens were studied with LM and SEM. The polarity, aperture orientation and tetrad type allow segregating the Patagonian grains from the Nypoideae and relating it to the Calamoideae subfamily. These records suggest an antique origin of monocots and a probably initial diversification of calamoid palms during the Early Cretaceous in high latitudes of Gondwana. The presence of palmae during the Early Cretaceous in southern South America suggests a warm and humid climate, similar to that found in present days at tropics.  相似文献   

10.
Foraminifers representing species Kaeveria fluegeli have been found in the Zorkaradjilga Formation (Sagenites quinquepunctatus Zone) of the upper Norian (or lower Rhaetian) in the central structural-facies zone of the South-East Pamirs. Their occurrence here is an additional criterion substantiating age and correlation of host deposits and an evidence in favor of fauna migration from the southern Tethys during the respective time span not only in northwestern areas of that ocean (Northern Calcareous Alps), but also in its central part (the South-East Pamirs).  相似文献   

11.
12.
A new species, Procretevania mitis sp. nov., is described from the Early Cretaceous of Yixian Formation at the Huangbanjigou, Beipiao City, western Liaoning, China. Based on new morphological data, a key of Procretevania Zhang and Zhang, 2000 is provided. Forewing venations, body and forewing lengths, localities and horizons of various genera of Evaniidae in amber and compression fossils are summarized for comparison. Evaniidae have a high degree of venational diversity, while more complex forewing venations for Lebanevania and Mesevania suggest that they may represent the stem group of the Evaniidae. High diversity of Evaniidae in the Early Cretaceous implies that Evaniidae might have radiated before the Early Cretaceous. Furthermore, comparison of body and forewing lengths of amber and fossil genera indicate that the amber specimens have relatively smaller size.  相似文献   

13.
Actinopterygian remains have been recovered from Upper Cretaceous (lower Campanian to lower Maastrichtian) marginal marine deposits of the Adaffa Formation in northwestern Saudi Arabia. The fossils comprise gars (Lepisosteidae), pachycormids (cf. Protosphyraena sp.), indeterminate pycnodontiforms, enchodontid teleosts (cf. Enchodus sp.) and other indeterminate Teleostei. This assemblage is significant because it includes a novel occurrence for the Middle East (Pachycormidae) together with taxa (Lepisosteidae, Pycnodontiformes, Enchodontidae) that have been previously recorded from Late Cretaceous faunas elsewhere in the Mediterranean Tethyan region.  相似文献   

14.
The Neogene–Quaternary volcanic products, related to Arabian and Anatolian Plate collision along the Bitlis Suture Zone, cover wide areas on both plates. One of these volcanic exposures on the Arabian Plate is the Kepez volcanic complex (KVC). This study aims explain to petrogenesis of KVC. Although some examples display alkaline affinities, the majority of the volcanic rock is calc-alkaline and can be defined in three main groups. 40Ar/39Ar data obtained from dacite, basalt and andesite rock groups within the KVC yield ages of between 13.5 and 15.5 Ma. Geochemical and petrographical data show that the andesitic rocks are products of homogeneous mixing between basic end-member magmas and dacitic magmas which are the products of partial melting of lower crustal compositions. Basaltic products of KVC are asthenospheric mantle derived, while dacitic and andesitic volcanic rocks are crustal origin. High Sr and Nd isotope ratios may indicate that andesitic and dacitic rocks originated from continental crust. The lithospheric mantle, which is subducting underneath the Anatolian plate, must have experienced slab break-off processes 13–15 million years ago and sunk into the asthenosphere. KVC were produced with the collision between Arabian and Anatolian Plates and related uplift of the East Anatolia region.  相似文献   

15.
The left-lateral Amanos Fault follows a 200-km-long and up to 2-km-high escarpment that bounds the eastern margin of the Amanos mountain range and the western margin of the Karasu Valley in southern Turkey, just east of the northeastern corner of the Mediterranean Sea. Regional kinematic models have reached diverse conclusions as to the role of this fault in accommodating relative motion between either the African and Arabian, Turkish and African, or Turkish and Arabian plates. Local studies have tried to estimate its slip rate by K–Ar dating Quaternary basalts that erupted within the Amanos Mountains, flowed across it into the Karasu Valley, and have since become offset. However, these studies have yielded a wide range of results, ranging from 0.3 to 15 mm a−1, which do not allow the overall role and significance of this fault in accommodating crustal deformation to be determined. We have used the Cassignol K–Ar method to date nine Quaternary basalt samples from the vicinity of the southern part of the Amanos Fault. These basalts exhibit a diverse chemistry, which we interpret as a consequence varying degrees of partial melting of their source combined with variable crustal contamination. This dating allows us to constrain the Quaternary slip rate on the Amanos fault to 1.0 to 1.6 mm a−1. The dramatic discrepancies between past estimates of this slip rate are partly due to technical difficulties in K–Ar dating of young basalts by isotope dilution. In addition, previous studies at the key locality of Hacılar have unwittingly dated different, chemically distinct, flow units of different ages that are juxtaposed. This low slip rate indicates that, at present, the Amanos Fault takes up a small proportion of the relative motion between the African and Arabian plates, which is transferred southward to the Dead Sea Fault Zone. It also provides strong evidence against the long-standing view that its slip continues offshore to the southwest along a hypothetical left-lateral fault zone located south of Cyprus.  相似文献   

16.
Cervical vertebrae of elasmosaurids (Sauropterygia, Plesiosauroidea) have proven to be informative even at family level. The present paper uses a previously developed methodology based on bivariate graphic analysis that evaluates the proportion indices of cervical vertebrae in elasmosaurids, which is applied to a well-preserved postcranial specimen of this group recovered from upper Maastrichtian beds of central Chile. The plotting of such indices groups the Chilean material with other specimens from the Late Cretaceous of Argentina and Antarctica, the latter referred to the genus Aristonectes. This result allows us to identify the first relatively complete individual of the genus based on non-cranial characters. The identification of the Chilean specimen as Aristonectes sp. provides important new data on the postcranial skeleton of the genus, that has remained poorly known until now.  相似文献   

17.
The upper member of the Jafnayn Formation in Wadi Rusayl and Al Khoud, Seeb Area in north Oman contains Nemkovella stockari Less & Özcan, 2007, an Early Eocene orthophragminid recorded here for the first time from the Arabian Peninsula. N. stockari, the only orthophragminid identified in Jafnayn Formation, is quite distinct from any other species from Tethys in having spiral and orbitoidiform chambers around the isolepidine embryon developed before the onset of annular chambers. The Oman specimens exhibit equal-sized principal auxiliary chambers and symmetrical spirals and are assigned to N. stockari bejaensis Özcan, Boukhalfa & Scheibner, 2014, an advanced form of the N. stockari lineage. The associated alveolinids, revised in this study, rotaliids and other age-diagnostic foraminiferal taxa in the transgressive basal part of the upper member have enabled us to revise the age as middle Ilerdian (Early Eocene), assignable to SBZ 7/8 and 8; OZ 3/4. Integrating a new record of this species from Arabian Plate margin in Belen, S Turkey, and previous records from north Africa, N. stockari appears to be a diagnostic marker for the Early Eocene along the southern peri-Tethys platforms, facilitating the Tethyan correlation by orthophragminids. The palaeobiogeographic distribution of N. stockari is discussed.  相似文献   

18.
《Applied Geochemistry》2001,16(7-8):883-894
Total CO2 output from fumaroles, bubbling and water dissolved gases and soil gases was investigated at Pantelleria Island volcano, Italy. The preliminary results indicate an overall output of 0.39 Mt a−1 of CO2 from the island. The main contribution to the total output was from diffuse soil degassing (about 0.32 Mt a−1), followed by dissolved CO2 (0.034 Mt a−1), focussed soil degassing (0.028 Mt a−1) and bubbling CO2 (0.013 Mt a−1). The contribution of CO2 from fumarole gases was found to be negligible (1.4×10−6 Mt a−1). Carbon-13 values for CO2 coupled with those for associated He in gases from fumaroles and sites of focussed soil degassing clearly rule out any significant organic CO2 component and suggest a common mantle origin for these gas species. The inferred mantle source beneath Pantelleria would seem to have peculiar geochemical characteristics, quite distinct from those of mantle producing MORB but compatible with those of magmatic sources of central Mediterranean and central European volcanoes. These findings indicate that the Pantelleria volcanic complex is a site of active mantle degassing that is worthy of attention for future geochemical surveillance of the island.  相似文献   

19.
The Pelusium Line, which was defined by Neev (1975) off the Mediterranean coast of Israel, is suggested to form a transcontinental arcuate shear which extends along the following three segments:
1. (A) from Anatolia along the eastern Mediterranean down to the eastern limit of the Nile Delta;
2. (B) across Africa down to the Niger Delta; and
3. (C) across the Mid-Atlantic Ridge along the equatorial fracture zones.
A “Central Plate”, composed of South and East Africa and the Arabian and Sinai subplates, has been left laterally shifted along the Pelusium Line relative to the Northwest African Plate.  相似文献   

20.
Yabeinosaurus was the first lizard genus described from the Early Cretaceous Jehol Biota of China. The holotype of the type species, Y. tenuis, is an immature skeleton but it has been lost for decades. A second species, Y. youngi, was erected based on another immature skeleton and is distinguished by its longer, more gracile limbs. In 2001, a juvenile skeleton from the Jingangshan locality of Liaoning was designated as the neotype for Y. tenuis. Subsequently, several further specimens from other localities, juvenile and adult, have been attributed to this species. Here we describe a second lizard specimen from the neotype locality. In anterior tooth shape, finger-like mandibular angular process, cranial sculpture, maxilla shape, and short, robust humerus, the new specimen resembles adult and subadult material currently attributed to Y. tenuis, but it differs in having bicuspid posterior teeth and a straight rather than a hooked angular process of the mandible. We propose a new species (Y. bicuspidens sp. nov.) for this specimen which represents the first occurrence of bicuspid teeth in an Early Cretaceous lizard from China. However, the recognition of a second species at the neotype locality raises a taxonomic problem. Due to the immaturity of the designated holotype and neotype of Y. tenuis, they cannot be coded for the jaw and dental characters that distinguish the two robust-limbed species. This renders Yabeinosaurus tenuis a nomen dubium. Here we propose that Yabeinosaurus tenuis should be treated as a historic taxon, permitting retention of the generic name under ICZN rules, and erect a second new species (Y. robustus sp. nov.) for the principal robust-limbed morphotype in the Jehol Biota with monocuspid posterior teeth and a hooked angular process.  相似文献   

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