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1.
New Late Permian fishes combining features characteristic of several classes are analyzed and redescribed. They were assigned to the family Discordichthyidae of the order Discordichthyiformes comprising three genera and four species: Mutovinia stella Minich, Geryonichthys longus A. Minich, G. burchardi A. Minich, and Discordichthys spinifer A. Minich (Minikh, 1998). A new species, Mutovinia sennikovi sp. nov., is described. Due to rapid evolutionary replacement, discordichthyids are rather useful stratigraphically. The photographs of the skeleton and membrane bones of these fishes are published for the first time.  相似文献   

2.
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   

3.
Reinvestigation of Nystroemia pectiniformis Halle from the Upper Shihhotze Formation of Shanxi Province, China, has led to the identification of new and important features of this enigmatic Late Permian seed plant, permitting its typification and diagnosis. After reassembling several of the previously studied specimens to form a single articulated branching system comprising at least four orders of branching, previously unknown features of its branching pattern and morphology have been characterized. First–order axes are wide and branch to one side only, bearing second–order branches either singly or in pairs and of two kinds: one fertile and bearing characteristic ovulate branching systems and the other presumably vegetative. Ovulate second–order axes are narrow and branch to one side only, producing numerous, closely spaced lateral branches in two alternate to sub–opposite rows. Lateral branches are slender and produce numerous ovulate branching systems to one side of the axis only. Ovulate branching systems divide unequally to produce 3–15 ultimate axes of different lengths that are planated. Each ultimate axis bears a single terminal ovule with 180 degree rotational symmetry and two horn–like integumentary projections distally. The other kind of second–order axes are distinct from those bearing ovules; they are wider and longer and branches occur on both sides of the secondary axis, lacking divisions in close proximity to the first–order axis. These have only been observed incomplete although their distinct morphology indicates they are unlikely to be ovulate branches from which ovules/seeds have been shed. Additional organs of the Nystroemia plant are considered, including pollen organs previously assigned by Halle to the same species (displaying its characteristic branching style), and also leaves of Chiropteris reniformis Halle that were probably borne on the larger kind of second–order branches. Implications of Nystroemia on seed plant evolution and distribution are discussed, and it is concluded that this most likely represents a late stratigraphic occurrence of a plesiomorphic hydrasperman–type seed plant with affinities closely allied to members of the Lyginopteridales.  相似文献   

4.
The family Palaeolithocycliidae Kozur and Mostler was formerly thought to be ranging from Devonian to Carboniferous. However, a lot of radiolarians assignable to this family were discovered in the late Changhsingian (Latest Permian) of South China. Six species, including Palaeolithocyclia pilata n. sp., Palaeolithocyclia platta n. sp., Paramphibrachium woni n. sp., Klaengspongus spinosus Sashida, Klaengspongus formosus n. sp. and Klaengspongus umbilicatus n. sp., have been identified. In this paper, these species are illustrated and described.  相似文献   

5.
A problematic organism, Bowengriphus perphlegis gen. et sp. nov., is described based on two specimens from the Late Permian Rangal Coal Measures of eastern central Queensland. It displays a double-looped feeding apparatus bearing small conical elements, considered homologous with that of the supposed lophophorate Odontogriphus omalus Conway Morris, 1976, from the Middle Cambrian Burgess Shale of British Columbia, Canada. Odontogriphids are thus interpreted as a group that survived through the Palaeozoic and made the transition from marine to freshwater environments. Recent proposals that odontogriphids are stem-group chordates are not well established.  相似文献   

6.
Exceptionally well-preserved specimens of Mizzia yabei (Karpinsky) were discovered in bituminous packstone intercalations of the early Upper Permian Maokou Formation of Anxian County (Sichuan, China). Staining techniques and x-ray diffraction reveal that the organic encrustation around the central stem and the lateral branches consists of aragonite. Average aragonite contents range between 27% and 40%. The bulk of the remaining 60–73% calcite represents cement. The total Sr-content is 3, 400 ppm, indicating 8,000–10,000 ppm for the aragonite fraction. The organically precipitated aragonite was deposited as closely packed fibres, 10–20 μm long and 0.5–1 μm wide. The fibres are arranged in clinogonal (water-jet) fascicles, which diverge towards the central (spar-filled) stem. This microstructure shows that the mineralization of the mucilage started at the periphery of the extracellular encrustation and progressed toward its interior. Diagenetic alterations of the original aragonite include various stages of breakdown of the fibres into 0.5–1 μm large granules (micritization), minor syntaxial growth of the fibres and local transformation of acicular aragonite into neomorphic calcite. The dasycladaleans from the Permian of Sichuan appear to be by far the oldest representatives of this order with preserved aragonitic mineralogy and microstructure. Comparably well-preserved examples are only known from Eocene and younger deposits.  相似文献   

7.
A diverse and well-preserved latest Permian radiolarian fauna was obtained from bedded siliceous rocks and siliceous mudstones of the Dongpan Section, southwest Guangxi, China. All encountered specimens of the order Spumellaria and a few specimens of the order Entactinaria were selected for the taxonomic study of this paper. Thirty-three species, 15 of which are new species, were identified. They belong to 15 genera, three of which (Paracopicyntra, Copiconulus, and Yujingella) are new. The most interesting result of our study is that eight typical Middle Triassic spumellarian genera (Paroertlispongus Kozur and Mostler, Tetrapaurinella Kozur and Mostler, Paurinella Kozur and Mostler, Lithelius Haeckel, Archaeospongoprunum Pessagno, Tamonella Dumitrica, Kozur and Mostler, Bistarkum Yeh, and Tetraspongodiscus Kozur and Mostler) were discovered in the upper Changhsingian strata studied herein. Therefore, the most important and characteristic spumellarian families of the Middle Triassic were already present in the Late Permian of South China.  相似文献   

8.
Sinoagetopanorpa permiana n. gen., n. sp., first Chinese Permian Agetopanorpinae, is described and compared to the other genera of this group.  相似文献   

9.
Gorochov AV 《ZooKeys》2011,(130):131-136
Alexarasniidaefam. n. and Alexarasnia rossicagen. et sp. n. are described from the Upper Permian of European Russia. Systematic position of this enigmatic family within the infraclass Polyneoptera is unclear.  相似文献   

10.
Two new genera (Sinosphaera and Trigonosphaera), including two new species and another left in open nomenclature, are described from the Changxingian (upper Permian) of southern Guangxi, southern China. They are characterized by a single spherical, subspherical or rounded triangular cortical shell composed of two spongy layers and the likely absence of both a medullary shell and internal spicule. They are tentatively grouped within the family Xiphostylidae Haeckel, 1881 and are considered as the most primitive representatives of this family.  相似文献   

11.
《Palaeoworld》2022,31(3):402-418
Sphenophyllum Brongniart constitutes a common and important element in the Carboniferous and Permian floras around the world, but its records in the Devonian Period are limited and remain to be investigated with respect to their morphology, anatomy, and distribution. Diversity of Sphenophyllum during Late Devonian in South China was significant with the presence of the well-known species including S. lungtanense Gothan and Sze, S. pseudotenerrimum Sze, and S. changxingense Huang et al. In this article, we describe a new species of the genus, S. fanwanense n. sp., from the Fanwan section of Changxing County, Zhejiang Province, characterized by having at least two orders of axes, with six spoon-shaped leaves attached at the node. A comprehensive review of previous records of Sphenophyllum from the Upper Devonian of South China shows that at least four species (S. fanwanense, S. lungtanense, S. pseudotenerrimum and S. changxingense), each with distinct leaf morphology, occur in South China in the Late Devonian, mostly from the Wutong Formation (Famennian). Given the lack of concrete evidence for anisophylly or heterophylly among the Devonian Sphenophyllum species (and more broadly, the Devonian sphenopsids), we suggest that the development of these features later in the Carboniferous and Permian periods was likely related to an increase in complexity of forest communities through time.  相似文献   

12.
Specimens of the platform element of Neogondolella from the Upper Permian of the Meishan section show well-developed polygonal microsculpture on their oral surfaces, attributable to the imprints of secreting cells. In all populations studied, there is a small but significant increase of mean polygon size with element size, but no variation in polygon size related to position on the element. There is a difference in mean polygon size between the two species N. changxingensis and N. deflecta , but this appears merely to reflect the larger mean size of elements of the latter species. No evidence for periodicity of polygon size during ontogeny is detected. The population of N. changxingensis in Bed 24e is dominated by small specimens with a mean polygon size smaller than on equivalent-sized elements in the normal population of Bed 24d; this suggests that the 'dwarf' population reflects a combination of high juvenile mortality and retarded cell growth.  相似文献   

13.
Microfacies analyses performed on the latest Permian Wujiaping Formation at Laren (Guangxi Province, South China) show that the bioclastic-rich limestones of Late Permian age contain a rich and well-diversified foraminiferal fauna. This fauna is here revised in order to be compared with time-equivalent levels of southern Iran and southern Turkey. Some new and unexpected phylogenetic trends are highlighted among the biseriamminoids. The new or poorly known genera Retroseptellina, Septoglobivalvulina, Paraglobivalvulinoides, Dagmarita?, Bidagmarita nov. gen., Louisettita, Paradagmaritopsis nov. gen. and Paradagmarita? are concerned. Nevertheless, these newly appeared biseriamminoids are subordinate to abundant Tetrataxis and Climacammina, ultimate survivors of the families Palaeotextulariidae and Tetrataxidae, appeared as old as the Early Carboniferous (“Mississippian”). Algae, miliolids, and nodosarioids are poorly represented. Two genera and four species are here newly described: Globivalvulina curiosa nov. sp., Louisettita ultima nov. sp., Bidagmarita nov. gen., Bidagmarita sinica nov. gen. nov. sp., Paradagmaritopsis nov. gen., Paradagmaritopsis kobayashii nov. gen. nov. sp. The palaeogeographic distribution of these foraminifers is interpreted to be typically of Neo-Tethyan regions, ranging from southern Turkey (Hazro) to South China (Laren) and up to Japan for some species (i.e., Paradagmaritopsis). At Laren, Late Permian strata are generally characterized by Reichelina ex gr. simplex Sheng. Isolated samples of packstones, collected in Tsoteng region (Guangxi Province, South China), contain Sphaerulina sp. together with various smaller foraminifers and numerous representatives of the new species G. curiosa nov. sp. In this study we demonstrate that the regions of Zagros (Iran), Taurus (Turkey), South China and even Japan shared similar foraminiferal assemblages and represented intermittently connected palaeobiogeographic provinces during Late Permian times.  相似文献   

14.
A new dicynodont genus and species, Idelesaurus tataricus sp. nov. (Cryptodontidae), from the Semin Ovrag locality (Tatarstan, Tetyushinskii District; Upper Permian, Upper Tatarian Substage, Severodvinian Horizon) is described. The skull patterns of the East European and South African Cryptodontidae and Aulocephalodontidae are compared from the morphofunctional point of view.  相似文献   

15.
Studies in the past decade have proven the Shanita fauna to be an excellent marker of the northern peri-Gondwana tectonic blocks.Thus,a study of the Shanita fauna from the Baoshan area in western Yunnan Province,China,could provide pivotal paleontological evidence for the paleogeographic reconstruction of the Baoshan block.We systematically analyzed the composition and the age of the Shanita fauna from the Permian Da'aozi Formation in Woniusi Section of the Baoshan area.Results suggested that the characteristic genera Shanita and Hemigordiopsis in this fauna comprised eight species (including two new species),and ten genera of other nonfusulinid foraminifera were also recognized from this fauna.Further comparative study showed that the Shanita fauna from the Baoshan area were probably late Maokouan (Lengwuan)to Wuchiapingian in age.In general composition,this fauna is comparable to those Shanita faunas from Shan State of Burma,Peninsular Thailand,and Nagri of Tibet,China.However,the relatively low generic diversity and occurrence of some endemic species,as well as the absence of fusulinids,indicate certain regional features of the Shanita fauna from the Baoshan area.  相似文献   

16.
Patranomodon nyaphulii , known from a nearly complete skull, lower jaw and partial postcranial skeleton, is morphologically the most primitive anomodont therapsid yet discovered. It is from the Eodicynodon Assemblage Zone, the lowest biozone of the Beaufort Group of South Africa, which has a primitive therapsid fauna comparable with that of the Russian Zone I. Patranaomodon is primitive with respect to other anomodonts in having short palatal exposure of the premaxilla, an unreduced tabular, a slit-like interpterygoidal vacuity, a screw-shaped jaw articulation (which precludes fore-aft sliding of the lower jaw), and only three sacral vertebrae. The poorly-known Galechirus and Galepus from the younger Cistecephalus Assemblage Zone appear to be at a comparably primitive evolutionary grade, and the three genera are tentatively united in the family Galechiridae. The taxon Dromasauria is shown to be paraphyletic and therefore should be discarded.  相似文献   

17.
Late Permian terrestrial faunas of South Africa and Russia are dominated taxonomically and ecologically by therapsid synapsids. On the basis of a single specimen from the Upper Permian of South Africa, the varanopseid Elliotsmithia longiceps is the sole basal synapsid ('pelycosaur') known from Gondwana. Recent fieldwork in the Upper Permian of South Africa has produced a second varanopseid specimen that is referrable to Elliotsmithia . Data from both this specimen and the holotype suggest that Elliotsmithia forms a clade with Mycterosaurus from the Lower Permian of North America and Mesenosaurus from the Upper Permian of Eastern Europe. That postulate is supported by the three most parsimonious trees discovered in a new analysis of varanopseid phylogeny. However, the available data cannot resolve the interrelationships of these three genera. The new phylogenetic results contrast with earlier work identifying Elliotsmithia as the basal member of a clade that includes the North American taxa Aerosaurus , Varanops , and Varanodon . The new trees reduce the stratigraphic debt required by the latter scenario, and the one with the least stratigraphic debt identifies Elliotsmithia and Mesenosaurus as sister taxa. Two new taxa are erected, Mycterosaurinae and Varanodontinae, for the two varanopseid subclades.  相似文献   

18.
The skull of a small anomodont therapsid, from the Tapinocephalus Assemblage Zone (Abrahamskraal Formation, Beaufort Group, Upper Permian) in Northern Cape Province, South Africa, represents a new basal dicynodont and is described in detail. Colobodectes cluveri gen. et sp. nov. is distinguished from other dicynodonts by an anteroposteriorly extensive caniniform process, parietals that were broadly overlapped posterolaterally by posterodorsal processes of the postorbitals, diverging anterior palatal ridges, and a dorsoventrally low foramen magnum. A phylogenetic analysis indicates that Colobodectes is the basalmost member of a dicynodont clade that excludes Eodicynodon . This position is not particularly strong, as two additional steps are needed to make Colobodectes and Eodicynodon oosthuizeni exchange places on the most parsimonious tree. Another discovery of the phylogenetic analysis is that there is little basis for recognizing Eodicynodon oelofseni as the closest relative of E. oosthuizeni . The former species is identified as the sister taxon of a clade that includes the latter and all other dicynodonts.  相似文献   

19.
A study of both silicified and nonsilicified specimens of Permian reticularioid brachiopods from South China suggests thatPermophricodothyris, a genus previously rarely reported from China, is actually very common and abundant in the Middle and especially Upper Permian of South China. This study also clarifies, for the first time, that many of the reticularioid brachiopod species previously described asSquamularia in fact belong toPermophricodothyris. The new data presented in this paper also allows a critical evaluation ofPermophricodothyris in relation to its closest allies:Phricodothyris, Squamularia, Bullarina andNeophricodothyris. The revision reveals that a total of 18Permophricodothyris species are present in the Middle and Upper Permian of South China, with only one species,P. squamularioides, having survived the Permian-Triassic mass extinction. Two species,P. grandis (Chao) andP. guangxiensis Han, Zhou & Wang, are redescribed here, providing critical new information on the morphology and taxonomy of these species.  相似文献   

20.
A new genus and species of stick insect is described and figured from Mount Halcon, on the Philippine island of Mindoro. Conlephasma enigma gen. et sp. n. is a stout, flightless, and apparently ground-dwelling species with vivid integumental colors. When disturbed, specimens spray a defensive secretion from the prothoracic exocrine glands. The systematic position of Conlephasma within Euphasmatodea is unclear. The elongated galealobulus and the trichome area located laterally in the galea, represent unusual apomorphic characters of the maxilla that could indicate affinities with Necrosciinae or Pseudophasmatinae. All tibiae exhibit the anareolate condition. Euplantulae are of two types: those of tarsomeres I–IV feature a nubby microstructure, whilst the one on the ventral side of the pretarsus is smooth. Males are characterized by the presence of a well-developed vomer on the tenth abdominal segment. A distinctive and apomorphic trait of female terminalia is represented by the elongated tenth abdominal tergum. Conlephasma can represent an interesting taxon for studies on the evolution of the stick and leaf insects.  相似文献   

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