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1.
María Jos Salas 《Geological Journal》2011,46(6):637-650
The ostracod fauna from the Floian (Lower Ordovician) strata of the Cordillera Oriental, Argentina (Acoite Formation) are documented. One new genus Acoitella and four species are recognized, two of which are new (Nanopsis victoria sp. nov. and Conchoprimitia frequens sp. nov.). The diversity of the Early Ordovician ostracod faunas of the Central Andean Basin is evaluated. Compared with other regions, the ostracod diversity, at generic and specific level, of the Cordillera Oriental was comparatively high during the Tremadocian (nine species recorded) and comparatively low during the Floian (four species recorded). The taxonomic composition of the fauna is similar during the entire Early Ordovician of the Cordillera Oriental, where it displays a high percentage of soanellids. The Floian assemblages are characterized by the dominance of the eridostracan C. frequens sp. nov. with a high percentage of nondimorphic palaeocopids: Nanopsis and two genera of the Soanellidae family (Saltite and Acoitella gen nov.). An ostracod shell bed is described and interpreted to be a parautochthonous assemblage, as a result of transport within the same habitat. The composition of the fauna, with the presence of Saltite and Nanopsis, shows significant affinities with East Gondwana. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
2.
Middle Tremadocian cephalopods from the Sierra de Mojotoro, Cordillera Oriental, NW Argentina, are assigned to Saloceras cf. sericeum (Salter) based on the siphuncle morphology and general shape of the conch. Saloceras sericeum (Salter) is known from the Upper Tremadocian and Floian of England and Wales, a region that formed part of eastern Avalonia during the Early Ordovician, located at a high southern latitude to the north of the Gondwanan margin. This is the oldest record of this genus and of the family Eothinoceratidae, and extends the geographical range of Saloceras, being the first positive record of its presence in Argentina and the Central Andean Basin. These remains are amongst the oldest cephalopods described from NW Argentina. They represent the third mid Tremadocian record of nautiloids at relatively high palaeolatitudes and away from the low latitude carbonate platform palaeoenvironments where the bulk of the earliest cephalopods resided. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
3.
Ostracod from the upper Lower to Middle Devonian rocks of the Argentine Precordillera Basin (Talacasto and Punta Negra formations) are studied. One new genus Pircawayra nov. gen., and five species (including three new: Pircawayra gigantea nov. gen. and sp., Lapazites trinodis nov. sp. and Keslingiella? teresae nov. sp.) are defined. The recorded ostracod fauna closely resembles that coeval from Bolivia and South Africa, exhibiting a remarkable endemism, not only at the genus level, but also at the species level. In addition to its low-diversity, the Malvinokaffric ostracod association is also characterized by having large, thick, coarsely ornamented and swollen valves. The similar ostracod composition from the Andean and South African basins suggests faunal exchange between these two areas. Based on the ostracod faunas, the Malvinokaffric Realm is clearly recognizable at least up to the Middle Devonian. 相似文献
4.
《Journal of Asian Earth Sciences》2011,40(6):760-769
The leaves of Gangamopteris McCoy are the dominant constituent of Glossopteris flora in Lower Permian sequences of Gondwana. Morphologically leaves are similar with Glossopteris Brongniart in having reticulate venation pattern but differ in the absence of midrib. Large number of plant fossils collected from the carbonaceous shale samples of Barakar coal seams (Lower Gondwana) of Satpura Gondwana Basin, India indicates the presence of number of specimens of Gangamopteris belonging to sixteen species including two new species viz., Gangamopteris sethiaensis sp. nov. and Gangamopteris satpuraensis sp. nov.The morphological diversity, stratigraphical distribution and character affiliation of Gangamopteris demonstrate its organizational involvement towards the development of Glossopteris and signify the evolutionary lineage in Glossopteridales. 相似文献
5.
Twenty-nine megaspore species including six new taxa (Bacutriletes otwayensis sp. nov.,Erlansonisporites cerebrus sp. nov., Erlansonisporites decisum sp. nov., Hughesisporites coronatus sp. nov., Hughesisporites dettmanniae sp. nov., and Verrutriletes depressus sp. nov.) are documented from Aptian and Albian strata of the Gippsland and Otway basins, southeastern Australia. Together with six taxa known only from underlying Neocomian strata, these megaspores are used to establish four provisional biozones for the Lower Cretaceous that complement existing biostratigraphic schemes based on miospores and plant macrofossils. Megaspores are best represented in silty floodbasin facies and it is likely that the parent plants predominantly occupied moist understorey to fully aquatic habitats on the floodplain. Megaspores are sparsely represented in most other fluvial facies chiefly due to reworking of floodbasin sediments into higher energy channel and crevasse deposits. The relatively high diversity of lycophyte and fern megaspores contrasts with the scarcity of these plant groups in macrofossil assemblages. The megaspore record suggests that heterosporous cryptogams may have been significantly more prominent in the vegetation of this region than previously suggested. Several megaspores from southeastern Australia are closely comparable to forms from India and Argentina indicating broad similarities between Early Cretaceous heterosporous fern and lycophyte communities across Gondwana. These similarities also suggest that megaspores may be useful for inter-continental biostratigraphic correlation. 相似文献
6.
First Late Triassic Record of a Paleoentomofauna from South America(Malargüe Basin,Mendoza Province,Argentina) 总被引：1，自引：0，他引：1
Carsten BRAUCKMANN Oscar F. GALLEGO Norbert HAUSCHKE Rafael G. MARTINS-NETO Elke GROENING Jan-M. ILGER María B. LARA 《《地质学报》英文版》2010,84(4):915-924
<正>Late Middle Triassic to early Late Triassic insects from Argentina have been previously described from the Bermejo and Cuyana Basins where they have been recovered from the Ischichuca-Los Rastros and Potrerillos-Cacheuta Formations,respectively.The insect fauna discussed herein was collected during field studies in 1986/1987 from the Llantenes section(Norian to Rhaetian? Late Triassic),which is situated in the Malargue Basin in southern Mendoza province.The insect remains were found in the upper part of the Llantenes section (Llantenes Formation),which is built up of two coarsening-upwards cycles reflecting a deltaic progradation of a fluvial into a lacustrine environment(lower part),succeeded by repeated progradations into a floodplain-dominated environment(upper part;with finds of insects,conchostracans,fish remains,plant fragments,and drifted logs).The new finds represent the youngest Triassic insect records described from Argentina and even from South America in its entirety.There is only one contemporaneous fossil assemblage in Gondwana:in the Clarence/Moreton Basin(Aberdare Conglomerate;Late Norian)in Australia.The new Triassic insects include an impression of an isolated Mecopterida-like wing(Mendozachorista volkheimeri gen.et sp.nov.; Mendozachoristidae fam.nov.),coleopteran elytra of the Permosynidae(Ademosyne rosenfeldi sp.nov.and Ademosyne llantenesensis sp.nov.)and other isolated body fragments.This new Late Triassic entomofauna from Argentina is of considerable importance in the reconstruction of the biotic recovery of continental environments in Gondwana after the catastrophic mass extinction at the P/T boundary. 相似文献
7.
T. V. Filimonova 《Stratigraphy and Geological Correlation》2010,18(7):687-811
Among the smaller foraminifers from the Lower Permian of Western Tethys (Pamir, Northern Afghanistan, Central and Eastern
Iran, Armenia, and Turkey), foraminiferal assemblages characteristic of the Asselian, Sakmarian, Yakhtashian, Bolorian, and
Kubergandian stages are distinguished. The first stratigraphic scheme based on smaller foraminifers is elaborated for the
Lower Permian (Cisuralian Series) of Western Tethys. Eight biostratigraphic units distinguished in the Lower Permian and one
in the Kubergandian Stage are ranked as beds with characteristic foraminiferal assemblages. At particular stratigraphic levels,
the beds are recognizable in different paleogeographic provinces of the Tethyan Realm, which enables correlation between deposits
concurrently accumulated under dissimilar climatic and facies conditions to be carried. Some of the distinguished beds are
recognizable beyond the Tethyan Realm, for instance in the Donetsk basin, Cis-Urals, Pechora coal basin, and Spitsbergen.
Among foraminifers that have been studied, 264 species and subspecies, including 16 new taxa, are identified. The following
species and subspecies are identified and described for the first time: Hemigordius permicus beitepicus subsp. nov., H. pamiricus sp. nov., Neohemigordius afganicus sp. nov., N. carnicus sp. nov., N. bangi sp. nov., N. zulumarticus sp. nov., N. kubergandinicus sp. nov., Geinitzina grandella sp. nov., G. dentiformis sp. nov., G. bella sp. nov., Pachyphloia paraovata minima sp. nov., P. aucta sp. nov., Frondicularia porrecta sp. nov., Globivalvulina gigantea sp. nov., G. compacta sp. nov., and G. explicata sp. nov. 相似文献
8.
The Cretaceous witnessed the greatest diversity of Gondwanan notosuchian crocodyliforms, which displayed high levels of diversity and a notable array of specialized forms that developed in different ecological niches. Among this diversity, the advanced notosuchians are a clade of mid body sized forms which displays a remarkable abundance but is restricted to two lithological units from the Late Cretaceous of South America, the Adamantina Formation in southeastern Brazil and the Bajo de la Carpa Formation in Patagonia (Argentina). The only exceptions known so far were the Late Cretaceous Labidiosuchus from the Marilia Formation in Brazil and Yacarerani from the Cajones Formation in Bolivia. Herein we report a new Cretaceous crocodyliform, Llanosuchus tamaensis gen. nov. et sp. nov., found in the Los Llanos Formation (Campanian?) in northwestern Argentina (La Rioja Province). The small specimen includes well preserved fragments of the cranium and mandible with an estimated skull size of about 9 cm lengths. This crocodyliform shares several derived characters with Notosuchus terrestris from the Bajo de la Carpa Formation (Patagonia) and it was found in a weakly developed sandy paleosol profile formed in wet local conditions but in a region characterized by semi-arid climate and active eolian sedimentation. The presence of a new advanced notosuchian in the Cretaceous of western Gondwana, and its intermediate geographical region between the known South American species (Brazil, Argentina and Bolivia), has interesting implications, and adds another record of an advanced notosuchian in deposits with inferred warm climates and semi-arid paleoenvironments. Finally, Llanosuchus tamaensis supports a Late Cretaceous age for Los Llanos Formation with important geological implications for La Rioja Province. 相似文献
9.
A Wordian (Middle Permian) cephalopod fauna consisting of four ammonoid species, Tauroceras aff. scrobiculatum (Gemmellaro), Agathiceras sp., Bamyaniceras orientale n. sp. and Pronoritidae gen. and sp. indet., and two nautiloid species, Tainoceras sp. and Orthocerida fam. indet., were recovered from the Bera South area, southern Pahang, Peninsular Malaysia. The outcrop represents the southernmost extent of the Bera Formation. Bamyaniceras and Tainoceras are recorded in Malaysia for the first time. The presence of T. aff. scrobiculatum suggests a regional correlation with an ammonoid-bearing bed of Sungai Cheroh, western Pahang, and permits global correlations with strata of northeastern Iraq, northern Oman and Sicily (Italy). A possible eastwards faunal migration through the southern Tethys is suggested. 相似文献
10.
《Gondwana Research》2014,25(1):420-437
A new assemblage of early Cambrian bivalved arthropods (Bradoriida) is described from the Arrowie Syncline in the northern Flinders Ranges, South Australia. The well preserved, largely endemic fauna comprises a total of six taxa (including five new species): Jiucunella phaseloa sp. nov., Jixinlingella daimonikoa sp. nov., Mongolitubulus anthelios sp. nov., Neokunmingella moroensis sp. nov., Phasoia cf. spicata (Öpik, 1968), and Sinskolutella cuspidata sp. nov. This assemblage is derived from a carbonate sedimentary package representing a high energy, shallow water archaeocyath-Renalcis biohermal facies of Terreneuvian, Stage 2 age which transitions up-section to a more restricted, low energy, intra-shelf lagoonal environment that correlates with a Cambrian Series 2, Stage 3 age. The new taxon J. phaseloa sp. nov., has a first appearance datum (FAD) in shallow water biohermal facies of the Hideaway Well Member of the Wilkawillina Limestone at a level 47 m below the FAD of Pelagiella subangulata which is taken to approximate the base of Series 2, Stage 3 in South Australia. Along with Liangshanella circumbolina, this makes J. phaseloa sp. nov. amongst the oldest bivalved arthropods in South Australia and potentially greater Gondwana. The presence of 25 bradoriid taxa from the early Cambrian of South Australia suggests East Gondwana represents a major centre of origin for the Bradoriida. 相似文献
11.
A diverse fauna of wasps of the extinct parasitoid family Stigmaphronidae (Ceraphronoidea) are recorded in Early Cretaceous (Lower Albian) amber from Spain. Seven new species in five genera are described and figured based on 51 specimens, representing more material than in all the world’s other amber deposits combined. New species include: Elasmophron mari sp. nov., Libanophron sugaar sp. nov., Hippocoon basajauni sp. nov., Burmaphron jentilak sp. nov., B. sorginak sp. nov., B. iratxoak sp. nov., and Tagsmiphron olentzero sp. nov. The significance of the fauna is discussed and compared with that of other Cretaceous amber deposits, in particular the tremendous richness of the Spanish fauna is contrasted with the complete absence of stigmaphronids in the slightly younger and nearby French amber. Whether this stark difference represents particularly favorable conditions for these parasitoids, or their hosts, in the Cretaceous Spanish archipelago, or whether it is owing to taphonomic factors is discussed. 相似文献
12.
The following new fossil trichopteran insects are described or revised from the Purbeck Limestone Group and Wealden Supergroup of southern England: Pteromixanum inviolatum gen. et sp. nov., P. ruderatum gen. et sp. nov., P. purbeckianum (Handlirsch) gen. et comb. nov. and P. poxwellense gen. et sp. nov. (Necrotauliidae);Purbimodus minor gen. et sp. nov., P. medius gen. et sp. nov., P. rasnitsyni gen. et sp. nov. and P. saxosus gen. et sp. nov. (Vitimotauliidae);Palaeoludus popovi gen. et sp. nov. (Dysoneuridae);Palaeotarsus desertus gen. et sp. nov. (Plectrotarsidae);Eucrunoecia ridicula gen. et sp. nov. (Lepidostomatidae);Palaeocentropus placidus gen. et sp. nov. (Calamoceratidae) and Helicophidae gen. et sp. incertae sedis. The general composition of the fauna is compared with Early Cretaceous faunas of Asia. The early appearance of several living families is noted. 相似文献
13.
14.
A new large theropod, Orkoraptor burkei nov. gen. et nov. sp., from the Upper Cretaceous (Maastrichtian) Pari Aike Formation of southern Patagonia is based on a postorbital, quadratojugal, coronoid?, several teeth, an atlantal intercentrum and neurapophysis, two caudal vertebrae, and the proximal half of tibia. This new theropod exhibits characteristics of maniraptorans (i.e., coelurosaurians more derived than tyrannosaurids) including an upturned rostral process of the postorbital, the caudoventral corner of which is widely concave. Furthermore, teeth without denticles and carina in the mesial margin resemble the condition of the maniraptoran clades Compsognathidae and Deinonychosauria. The new Patagonian theropod differs from other coelurosaurians (Ornithomimosauria, Compsognathidae, Alvarezsauridae, Dromaeosauridae, Aves) in having caudal vertebrae with a single pair of small pleurocoels on each side, and in having a median depression flanked by two longitudinal and narrow furrows on each tooth. Orkoraptor represents one of the southernmost carnivorous dinosaurs yet found in South America and adds valuable information about the diversification of tetanuran theropods in Gondwana. 相似文献
15.
16.
David H. Evans 《Geological Journal》2007,42(1):25-36
A small cephalopod assemblage collected during the 1930s by J. A. Douglas from the Middle Ordovician San José Formation of Cuzco Province is redescribed. Although small in number (four taxa) and poorly preserved, this assemblage contains a representative of the ellesmerocerid family Eothinoceratidae and a probable member of the Arionoceratidae (Orthocerida). One taxon may be closely related to Protocycloceras harringtoni Cecioni from northern Argentina. The presence of a particular group of eothinoceratids, here and elsewhere in South America indicate a link with western Gondwana. The relatively diminutive size of the arionoceratids suggests homeomorphy with those Silurian forms associated with a pelagic habitat and indicates a relatively offshore site for this assemblage. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
17.
Situated at the easternmost area of the Late Mesozoic Jehol Biota, China, abundant fossils, including invertebrates, vertebrates and plants, were collected from the Early Cretaceous Yingzuilazi Formation of the Baishan Basin, southeastern Jilin. The faunal remains from this formation distinctly belong to the Early Cretaceous Lycoptera–Ephemeropsis–Eosestheria assemblage of the Jehol Biota. Based on the gross leaf morphology and epidermal structures, two new species and one indeterminate species of genus Solenites(Czekanowskiales), S. baishanensis sp. nov., S. gracilis sp. nov. and S. sp. are described in this paper. This is the first fossil plant of Czekanowskiales reported from this new fossil locality of the easternmost area of the Late Mesozoic Jehol Biota, China. The new discovery contributes to improve our knowledge for understanding of leaf morphology, epidermal characters and diversity of this genus during the Early Cretaceous time, and extends geologic and geographic distribution of Solenites in northern China and Eurasia. Along with consideration of associated plant and faunal assemblages and sedimentology, we suggest that the regional climate was warm and moderately humid with seasonal temperature and precipitation variations in warm–temperate zone during the Early Cretaceous. 相似文献
18.
A. P. Ippolitov 《Stratigraphy and Geological Correlation》2018,26(3):298-332
A representative early Bajocian belemnite assemblage containing four genera and 11 species (two identified in open nomenclature and five new: Eocylindroteuthis weisi sp. nov., E. mariottii sp. nov., E. yarkovi sp. nov., Homaloteuthis volgogradensis sp. nov., and Hastites orphana sp. nov.) is described from a section near the Dubovoi hamlet in the Greater Don Bend area (southern termination of the Don-Medveditsa dislocations). Some members of this assemblage were previously known from the Caucasus; however, it is possible to state the discovery of a Euroboreal belemnite fauna completely new for Russia, previously described only from Central Europe and almost unknown for Eastern Europe. The age of the studied assemblage collected from the lower part of the section, traditionally considered to be Upper Bajocian, corresponds to the Laeviuscula ammonite Chronozone and is the first reliable evidence of marine settings in the Volga Region for the early Bajocian. Two new biostratigraphic units, Beds with Eocylindroteuthis weisi and Beds with H. orphana, are introduced. The former, judging from the occurrences of its characteristic species in Western Europe, has a broad correlative potential. On the basis of datings obtained, the scheme of the formational subdivision of the Middle Jurassic of the Volga Region near Volgograd is revised, and the formerly abandoned Bakhtemir Formation is reinstated as a valid unit. Its total range is reestablished as corresponding to the upper part of the Discites (?)/Laeviuscula Chronozone (lower Bajocian)–Garantiana Chronozone (upper Bajocian). 相似文献
19.
Plant fossils collected from the Bijori Formation of Satpura Gondwana Basin are described in detail from the type locality
as well as from other exposures. The assemblage is dominated by glossopterid remains with few specimens of pteridophyte of
Glossopteris flora viz. Santhalea bansloiensis, Neomariopteris sp., Trizygia speciosa and 20 species of Glossopteris viz., G. angustifolia, G. searsoliensis, G. tenuifolia, G. surangei, G. kamthiensis, G. utkalensis, G. syaldiensis, G. sp. cf G. zeilleri, G. stricta, G. bosei, G. intermittens, G. stenoneura, G. gopadensis, G. wilkinsonii, G. retifera, G. conspicua,
G. mohudaensis, G. browniana, G. communis, G. indica, Vertebraria indica, dispersed seeds of Cordaicarpustype and equisetalean axes with or without nodes and internodes. 相似文献
20.
The brachiopod fauna from the base of the Bryn Siltstone Formation (middle Caradoc), Glyn Ceiriog, north Berwyn Hills, North Wales, consists of Platystrophia elevata sp. nov., Salopia abbreviata sp. nov., Kiaeromena ungula (M'Coy) and unnamed species of Hesperorthis?, Reuschella and Bicuspina. The dominant brachiopod species, Leptaena (Leptagonia) ungula M'Coy, 1851 is revised and its current assignment to the leptaenid genus Kiaeromena confirmed, based on the examination of type and topotype material from the Bryn Siltstone Formation. Kiaeromena spjeldnaesi nom. nov. is proposed to replace the junior homonym K. ungula Spjeldnæs, 1957 for that congeneric species from the upper Caradoc rocks of Ringerike, southern Norway. The fauna as a whole is unusual within the context of the Anglo-Welsh province and may represent a rare preserved nearshore community. 相似文献