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1.
The Palaeozoic–Mesozoic transition is characterized not only by the most massive Phanerozoic mass extinction at the end of the Permian period, but also its extensive aftermath and a prolonged period of major biotal recovery during the succeeding Middle to Late Triassic. Particularly, Anisian insect species from units of the Lower to Middle Muschelkalk from the Central European Basin are rare. The specimens described here originated from the Anisian Wellenkalk facies (Lower Muschelkalk), Vossenveld Formation of the Winterswijk quarry, The Netherlands, and from the orbicularis Member (lowermost Middle Muschelkalk, Anisian) of Esperstedt near Querfurt (Saxony-Anhalt). Thus, the described insect remains from Winterwijk and Esperstedt expand our knowledge about Middle Triassic terrestrial arthropod communities and their palaeodiversity. A new species of Chauliodites (C. esperstedti sp. nov) is introduced.  相似文献   

2.
Zoophycos is a well-known trace fossil common throughout the Phanerozoic. Paleozoic forms show important differences in morphology and habitat distribution with respect to the Jurassic, Cretaceous, and Cenozoic ones. Therefore, Early–Middle Triassic is considered a crucial time-span for the understanding of the evolution of this trace fossil. So far, Early Triassic Zoophycos is unknown and Middle Triassic forms were recorded only in deposits from Thuringia. The morphology and paleoenvironment of Zoophycos from the middle–upper Muschelkalk of the Iberian Range is herein described. The best-preserved trace fossils occur in a dolomicritic bed Ladinian in age, and are represented by small forms with a subcircular, slightly lobed outline and very little penetration depth. They were deposited in a very shallow, quiet-water environment with transition to supratidal/emerged areas. The low diversity of both trace fossils and skeletal remains point to stressful conditions related to strong salinity variations and/or poor water circulation. A comparison was made with Zoophycos from Anisian deposits of the Muschelkalk in Germany. This showed that both forms are quite simple and penetrate only the shallowest tiers, although they are different in whorl outline and lobe shape. This confirms that, notwithstanding the morphological variability of this group, Zoophycos still maintained a quite simple structure in the Triassic. A shallow-water environment was deduced for both localities, confirming that at least until the Early Jurassic Zoophycos had not definitively migrated toward deep-water areas.  相似文献   

3.
Until recently, Tholodus, a rare ichthyosaur with spherical tooth crowns of the pressing–crushing type, has only been known from the Middle Triassic (Anisian) beds of Western Europe. A record of Tholodus remains in the Karazin Formation (Middle Anisian) of southern Primorye (Russian Far East) significantly expands the range of these reptiles.  相似文献   

4.
The first Mesozoic representative of the extinct archostematan beetle family Permocupedidae, Frankencupes ultimus, gen. et sp. nov., is described based on two isolated elytra from the Lower Anisian (Middle Triassic) Röt Formation of Lower Franconia, Germany. The new fossil occurrence extends the range of the family from the Lower Wuchiapingian (Upper Permian) up to the Anisian, and represents a fine example of a Lazarus taxon in the fossil record of beetles.  相似文献   

5.
The trend of species diversity and spatiotemporal distribution of spherical radiolarians of the genus Entactinia Foreman, 1963 in the Permian Period is analyzed. The center of origin of Permian entactinians in the Cis-Ural Paleobasin is established in the area of the modern interfluve of the Ural River and latitudinal current of the Belaya River on the Southern Urals. It is shown that the species composition of this genus almost completely changed in certain Permian epochs. Two forefather species of each new pleiad of Early, Middle, and Late Permian are revealed: Entactinia parapycnoclada and E. tyrrelli. Two new species of the Lower Permian radiolarians from the Southern Urals and Northern Mugodzhary, E. chernykhi sp. nov. and E. subquadrata sp. nov., are described.  相似文献   

6.
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   

7.
Middle Permian Inoceramus-like bivalves of the genera Kolymia Licharew and Cyrtokolymia Astafieva endemic to the East Boreal Biogeographic Realm are considered. Cyrtokolymia, previously regarded by the author as endemics of the Verkhoyansk–Okhotsk Province and including only the type species, are also recorded in the Kolyma–Omolon Province, where they are represented by the endemic species C. bobini sp. nov. An emended diagnosis of the genus Cyrtokolymia is provided. The genus Kolymia comprises about 30 species. The greatest diversity of Kolymia (24 species, 13 of which are endemic) is known from the Verkhoyansk–Okhotsk Province, which is the center of diversification of this genus. The Kolyma–Omolon Province is characterized by 12 species, only three of which are endemic. In other provinces of the East Boreal Realm, only individual members of Kolymia are known. From the Middle Permian of the Omolon Massif, northern Verkhoyansk Region, and Penzhinsky Ridge, the following new species are described: Kolymia posneri Muromzeva, Kusnezov et Biakov, sp. nov., K. pontoneica Biakov, sp. nov., K. simkiniformis Biakov, sp. nov., and Cyrtokolymia bobini Biakov, sp. nov.  相似文献   

8.
Fossil remains of beetles are described from two Lower Triassic localities: Entala (Induan) and Tikhvinskoe (Olenekian). Only one beetle fossil was previously known from the Lower Triassic of Tikhvinskoe. The fossils are rather few and poorly preserved, but they are worth describing as finds rare for the Lower Triassic. Five fossils from Entala most probably belong to beetles of the same species of the formal genus Pseudochrysomelites. Beetles of this genus are especially abundant in deposits close to the Permian–Triassic boundary and can be considered “disaster taxa.” There are no known cases, either in the Permian or in the Middle–Upper Triassic, of a random sample of five specimens belonging to a single species. This suggests that in the Entala oryctocenosis the species diversity of beetles is extremely low. All three beetle fossils found in Tikhvinskoe belong to beetles of different species, showing that diversity had already started to increase. However, it remained low, and all fossils belong to the formal family Schizocoleidae, and two of the three belong to the same genus, Pseudochrysomelites. The Khei-Yaga locality, which immediately follows Tikhvinskoe in time (topmost Olenekian or early Anisian), already contains beetles of the families Asiocoleidae and Permosynidae. In the Lower Anisian of the Buntsandstein, such typical Mesozoic beetles as Cupedidae and Coptoclavidae have been recorded. The appearance of such advanced beetles as early as the Lower Anisian suggests that the famous Permian–Triassic crisis was not as deep as it is usually believed, and many beetles survived it, disappearing, however, from the fossil record in the Early Triassic.  相似文献   

9.
Locustoblattina segmentata gen. et sp. nov. and L. marginata gen. et sp. nov., new members of the family Mesorthopteridae (Eoblattida) are described from the Middle Triassic of the Madygen locality (Ladinian Stage of the Kyrgyzstan). New members of the Alexarasniidae (Embiida), Alexarasnia limbata Aristov, sp. nov. and Nestorembia shcherbakovi sp. nov., are described from the Upper Permian Isady locality in the Vologda Region and the Madygen locality, respectively. Parastenaropodites fluxa Storozhenko, 1996 (Mesorthopteridae) is redescribed from Madygen. The origin of webspinners from within the Permian eoblattids and the composition of the superorder Blattidea are discussed.  相似文献   

10.
A new genus, Tologuica, with two species (T. aurorae sp. nov. and T. karhui sp. nov.), from the Middle Miocene of the Sharga locality (western Mongolia) is described. The new genus shares some characters with the extinct genera Palaeocryptonyx, Palaeortyx, and Plioperdix and with extant Coturnix. The foot structure suggests that Tologuica resembled in ecology the European genus Palaeortyx and was probably adapted to an arboreal mode of life, in contrast to the terrestrial Coturnix and Plioperdix.  相似文献   

11.
A late Changhsingian bivalve complex including species from the genera Palaeonucula, Dacryomya, Malletia ?, Sarepta ?, Myalina, Pteria, Maitaia, and Unionites is discovered in northeastern Asia for the first time. The transition from the Permian to the Triassic in high-boreal basins has been shown to include two extinction episodes similar to those observed in the low-boreal basins and apparently evoked by trap volcanism activation in Siberia. Changes in benthic foraminifera diversity and vertical distribution of ammonoidea of the genus Otoceras in transitional Permian–Triassic deposits also are considered. Images of bivalves from the most typical taxa are presented.  相似文献   

12.
Beetle remains from the Triassic Khey-Yaga locality, Nenets National District, Korotaikha Basin, Nyadeita Formation, Olenekian-Anisian are described. Only isolated elytra have been found. Tetracoleus tshalyshevi gen. et sp. nov. and T. minimus sp. nov. are described and assigned to Tricoleidae, and six new species are described in formal taxa. Tetracoleus is close to Permian tricoleids just found in the Newcastle Group of Australia and the Vyatkian Aristovo locality of northern European Russia. The composition of elytra in the locality is closer to that of Lower Triassic localities than other Middle Triassic localities and characterizes the beginning of a recovery after the Permian-Triassic ecological crisis. Longxianocupes Hong in Liu, Liu et Hong, 1985 is shown to be a junior synonym of Sogdelytron Ponomarenko, 1969. The species Palademosyne ovum Ponomarenko, 2004, P. elongatum Ponomarenko, 2004, and P. latum Ponomarenko, 2004 are transferred to the genus Pseudochrysomelites Handlirsch, 1906.  相似文献   

13.
New concepts of systematics and phylogeny of the Permian Inoceramus-like bivalve mollusks of the eastern part of the Boreal zone are discussed based on analysis of the group’s historical development. All taxa studied are referred to the family Kolymiidae Kusnezov, which is divided into two subfamilies, Kolymiinae and Atomodesmatinae. In the subfamily Kolymiinae, two new genera are described: Praekolymia with the type species P. archboldi sp. nov. and P. urbajtisae sp. nov., and Taimyrokolymia with the type species T. ustritskyi sp. nov. In the subfamily Atomodesmatinae, two new genera, Costatoaphanaia and Okhotodesma, are described. The development of the group is shown to be generally autochthonous with some invasions (genus Atomodesma and, probably, Trabeculatia) from extraboreal regions.  相似文献   

14.
Representatives of the genus Trochammina are widespread in the Middle Jurassic of Arctic, Boreal, and Subboreal paleobasins. This group is important for stratigraphic and biofacial investigations. Foraminifers of the genus Trochammina, including T. praesquamata Mjatliuk and T. jakovlevae sp. nov. are described in detail.  相似文献   

15.
Trichasteropsis Eck, from the Muschelkalk of Germany is the only Triassic asteroid known from more than fragmentary material. Most spécimens representT. weissmanni (Münster) whereasT. senfti ECK,T. bielertorum n. sp., andBerckhemeraster charistikos n. gen. et n. sp., are each known from few individuals.Parsimony analysis hère treats the füll Ordovician to Récent history of the Asteroidea using a somasteroid (a pre-asteroid stelleroid) outgroup. Ambulacral évolution is critical in echinoderm history; the ambulacral arrangement of crown-group asteroids first appears in Paleozoic sister groups, and the subclass Ambuloasteroidea n. subcl. is proposed for Paleozoic and younger taxa with critical ambulacral apomorphies. Muschelkalk asteroids are assigned to the family Trichasteropsiidae n. fam., superorder Forcipulatacea. The recently described Triassic genusNoriaster belongs to the extant family Poraniidae, superorder Valvatacea.Trichasteropsis andNoriaster represent separate major phylogenetic branches of the post-Paleozoic infraclass Neoasteroidea, and together they indicate that diversification of modern-type asteroids was under-way during the Triassic, although the Mesozoic marine révolution largely was a Jurassic and later event. Post-Paleozoic asteroids appear to hâve returned to Paleozoic life modes in spite of new morphological expressions. Trichasteropsis is skeletally robust, suggesting protection from wave impact or predators. It is found in sédiments associated with shell banks but not from within the banks.Trichasteropsis senfti commonly occurs with brachiopods whereasT. weissmanni does not, although brachiopods are found in associated strata. Aspects of morphology of both species are similar to those of récent predatory Asteriidae suggesting similar behavior, but feeding habits ofTrichasteropsis are unverified.  相似文献   

16.
Dicroidium bandelii sp. nov. (Corystospermales) is described from the Um Irna Formation (Permian) of the Dead Sea Region, Jordan. The type and only specimen is a compressed frond fragment with cuticle. The new species is unique in showing pinnate frond architecture with elongate, lanceolate pinnae with a dense, near-parallel venation. In situ epifluorescence-microscopic analysis of the cuticle revealed evenly distributed, superficial stomata with differentiated lateral subsidiary cells typical of the genus. Epidermal and cuticular features readily distinguish D. bandelii from some superficially similar species of Ptilozamites or Thinnfeldia. Our report demonstrates that the diversity of Corystospermales in the unusual ‘mixed flora’ of the Permian palaeotropics is still greater than previously thought, and that the Um Irna Formation in particular holds a great potential for future palaeontological research.  相似文献   

17.
Two new coexisting species of crustacean copepods (Poecilostomatoida) belonging to the echinoid-specific genera Mecomerinx Humes, 1977 (Pseudanthessiidae) and Clavisodalis Humes, 1970 (Taeniacanthidae) found associated with the venomous flower urchin Toxopneustes pileolus (Lamarck) (Echinodermata: Echinoidea: Toxopneustidae) in the South China Sea (Vietnam) are described. The diagnostic features of Mecomerinx ohtsukai n. sp. are: (i) three setae and one aesthetasc on the first segment of antennules; (ii) relatively long caudal ramus; (iii) elongated terminal segment of the antenna; and (iv) two claws on the terminal segment of antenna slightly unequal in length. The taeniacanthid copepod Clavisodalis toxopneusti n. sp. is distinguished from all seven known congeners by having two-segmented endopod of the legs 2–4 and four setae on the distal endopodal segment of the leg 1. This is the first report on copepods associated with echinoids of the genus Toxopneustes Agassiz and the first finding of Mecomerinx as well as taeniacanthid copepods in the South China Sea associated with echinoids.  相似文献   

18.
The ammonoid family Sirenitidae from the Upper Carnian yakutensis Zone of northern Middle Siberia and Northeastern Asia is revised. A new genus Orientosirenites gen. nov. with the type species O. bytschkovi sp. nov. is established based on the study of the main morphological characters of the shell. The new genus and the species O. bytschkovi are described and the species O. yakutensis (Kiparisova) is redescribed. The new data allow the taxonomic composition and the distribution of the Carnian ammonoids of the Boreal Realm to be updated.  相似文献   

19.
Re-examination of the late Permian Tunguskagyrus planus Yan, Beutel et Lawrence, 2018 has shown that it does not belong to the family Gyrinidae (Adephaga) but should be placed in the family Triaplidae sensu n. (Archostemata) as a congener to “Triaplussibiricus Volkov, 2013 (Tunguskagyrus sibiricus (Volkov, 2013), comb. n.). Both these Palaeozoic species, in contrast to the Triassic members of Triaplus Ponomarenko, 1977, have no large metacoxal femoral plates and, therefore, would be better placed apart from the Mesozoic representatives of Triaplus (in a different genus). The synonymy of the family names Triaplidae Ponomarenko, 1977 (= Catiniidae Ponomarenko, 1968, syn. n., nom. praeocc., non Catiniidae Bocquet et Stock, 1957 (Crustacaea, Copepoda), = Coleocatiniidae Ponomarenko et Prokin, 2015, syn. n.) is established. Thus, the family now comprises Avocatinus Ponomarenko, 1969, Catinius Ponomarenko, 1968, Catinoides Ponomarenko, 1969, Macrocatinius Ponomarenko, 1969, Triaplus Ponomarenko, 1977, Triassocatinius Ponomarenko, 1969 and Tunguskagyrus Yan, Beutel et Lawrence, 2018.  相似文献   

20.
Two new genera (monotypic Samarabatrachus gen. nov. (S. bjerringi sp. nov.) and Syrtosuchus gen. nov. (including S. samarensis (Sennikov, 1981) and S. morkovini sp. nov) and a new species of the genus Selenocara Bjerring (S. rossica sp. nov.) are described based on revision of the original material of the form previously known as Wetlugasaurus samarensis. The genera Selenocara and Samarabatrachus gen. nov. positioned at the base of radiation of Triassic capitosaurids are combined into a new subfamily, Selenocarinae subfam. nov. The genus Syrtosuchus gen. nov., which is undoubtedly a derivative of early capitosaurids (Selenocara or a closely related genus), shows some typical benthosuchid features and is assigned to a separate benthosuchid subfamily, Syrtosuchinae subfam. nov. The diagnoses of the genera Wetlugasaurus Riabinin and Selenocara are amended. For the territory of the Obschii Syrt Highland, the genera Selenocara, Samarabatrachus gen. nov., and Syrtosuchus gen. nov. are regarded as key members of a separate Early Triassic tetrapod assemblage (Selenocara–Syrtosuchus Fauna), which is intermediate between the Tupilakosaurus and Benthosuchus faunas and dated Late Induan (Dienerian).  相似文献   

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