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1.
Exceptionally preserved ‘Burgess Shale‐type’ fossil assemblages from the Cambrian of Laurentia, South China and Australia record a diverse array of non‐biomineralizing organisms. During this time, the palaeocontinent Baltica was geographically isolated from these regions, and is conspicuously lacking in terms of comparable accessible early Cambrian Lagerstätten. Here we report a diverse assemblage of small carbonaceous fossils (SCFs) from the early Cambrian (Stage 4) File Haidar Formation of southeast Sweden and surrounding areas of the Baltoscandian Basin, including exceptionally preserved remains of Burgess Shale‐type metazoans and other organisms. Recovered SCFs include taxonomically resolvable ecdysozoan elements (priapulid and palaeoscolecid worms), lophotrochozoan elements (annelid chaetae and wiwaxiid sclerites), as well as ‘protoconodonts’, denticulate feeding structures, and a background of filamentous and spheroidal microbes. The annelids, wiwaxiids and priapulids are the first recorded from the Cambrian of Baltica. The File Haidar SCF assemblage is broadly comparable to those recovered from Cambrian basins in Laurentia and South China, though differences at lower taxonomic levels point to possible environmental or palaeogeographical controls on taxon ranges. These data reveal a fundamentally expanded picture of early Cambrian diversity on Baltica, and provide key insights into high‐latitude Cambrian faunas and patterns of SCF preservation. We establish three new taxa based on large populations of distinctive SCFs: Baltiscalida njorda gen. et sp. nov. (a priapulid), Baltichaeta jormunganda gen. et sp. nov. (an annelid) and Baltinema rana gen. et sp. nov. (a filamentous problematicum).  相似文献   

2.
We describe an assemblage of small carbonaceous fossils (SCFs) and acritarchs from cored siltstones of the Lappajärvi impact structure, west‐central Finland. Previous studies had detected a depauperate acritarch biota ascribed to a deep Proterozoic origin—this age, however, was based on recovery of long‐ranging poorly age‐diagnostic sphaeromorphs. To resolve the age and provenance of these crater sediments, we applied low‐manipulation processing techniques optimized for retrieval of larger organic‐walled microfossils. Our study revealed a previously undetected assemblage containing numerous metazoan SCFs consisting of flattened ‘protoconodonts’ (grasping spines assignable to total group Chaetognatha) and a distinctive fossilised chaeta, possibly representing the oldest known annelid remains. Phylogenetically problematic fossils include various acritarchs (large Leiosphaeridia sp., Tasmanites tenellus, smaller sphaeromorphs, Synsphaeridium, Archaeodiscina and Granomarginata) and filamentous forms (Palaeolyngbya‐ and Rugosoopsis‐like filaments, Siphonophycus), likely representing prokaryotic or protistan grades of organisation. As well as adding new diversity to an emerging SCFs record, these data substantially refine the age of these sediments by more than half a billion years, to an early Cambrian Terreneuvian age. More specifically, the assemblage is equivalent to that of the Lontova Formation from the Baltic States and northwest Russia, but is previously unreported from Finland. Identification of Lontova‐type SCFs/organic‐walled microfossils at Lappajärvi further constrains the poorly resolved extent of maximum flooding during the early Cambrian in Baltica. Renewed attention should be directed to strata that have thus far produced only biostratigraphically long‐ranging or ambiguous palynological assemblages—‘SCF‐style’ processing can reveal hitherto undetected, age‐informative microfossils that are otherwise selectively removed in conventional palynological studies.  相似文献   

3.
Animals with radial symmetry are abundant in the Cambrian Fortunian Stage of South China, but with relatively low diversity: representatives include Olivooides, Quadrapyrgites, carinachitiids, hexangulaconulariids and Pseudooides. Here, we report a new radial animal, Qinscyphus necopinus gen. et sp. nov., from the Fortunian small shelly fauna of southern Shaanxi Province, South China. Qinscyphus necopinus has a cup‐shaped profile, with slightly raised annuli and five groups of triangular thickenings in pentaradial symmetry. This organism has a comparable morphology to, and thus a close affinity with, Olivooides and Quadrapyrgites, and is interpreted as a coronate scyphozoan. This discovery adds a new crown‐group cnidarian to the Cambrian Explosion.  相似文献   

4.
Diverse assemblages of tanaidacean peracarid crustaceans from western Tethyan continental deposits suggest that the group was relatively common in or around ancient resin‐producing forests. Here we report the results of an examination of 13 tanaidacean specimens from three Cretaceous (Albian to Turonian) French amber deposits. Two new species of the fossil family Alavatanaidae are placed in the previously described Early Cretaceous genus Eurotanais: Eurotanais pyrenaensis sp. nov. from Cenomanian Pyrenean amber (Fourtou, Aude) and Eurotanais seilacheri sp. nov. from Turonian Vendean amber (La Garnache, Vendée). The remaining specimens are placed in three newly erected genera and species (but family incertae sedis): Arcantitanais turpis gen. et sp. nov. from Albian–Cenomanian Charentese amber (Archingeay, Charente‐Maritime), and Tytthotanais tenvis gen. et sp. nov. and Armadillopsis rara gen. et sp. nov. from Pyrenean amber. These are the first formally described fossils that might be related to the paratanaoidean families Nototanaidae and Paratanaidae, sharing with these some putatively derived features and providing possible evidence for the antiquity and morphological stability of these families and the suborder Tanaidomorpha. The distinctive features and character combinations of these fossil taxa are discussed in connection with possible relationships to the living lineages of tanaidaceans. Propagation phase‐contrast X‐ray synchrotron microtomography was used to obtain high‐quality 3D images for some fossils. A discussion is provided on the putative palaeobiology of tanaidaceans and the French resiniferous forest ecosystem. The discovery of these new tanaidaceans extends the palaeogeographical distribution and stratigraphical range of the family Alavatanaidae and sheds new light on the palaeoecology and diversity of tanaidaceans in pre‐angiospermous woodlands.  相似文献   

5.
本文描述古蝉科化石2新属、6新种,即Liaocossushuegen.etsp.nov.,L.beipiaoensisgen.etsp.nov,L.exiguusgen.etsp.nov,L.fengningensisgen.etsp.nov,L.Pingquanensisgen.etsp.nov.,Miracossusingentiusgen.etsp.nov.。这批化石保存有完整的虫体标本,使作者能够进一步研究古蝉类化石的虫体特征。化石采于冀北和辽西晚侏罗世义县组地层中,保存在中国地质博物馆。  相似文献   

6.
Knowledge of the Early Cretaceous ammonoids of the NW‐Himalayas was poor until recent discoveries. Intense sampling from the Giumal Formation exposed near the village of Chikkim (Spiti Valley, Himachal Pradesh, India) led to the recognition of a new Early Cretaceous ammonoid fauna. The succession consists of arenitic sandstone interbedded with shale that was deposited by turbidity currents on an unstable shelf in the Early Cretaceous. Ammonoids have been obtained only from sandstone beds in the lower one‐third and close to the top of the c. 350‐m‐thick section. Eight new ammonoid taxa (1 genus and 7 species) are described: Sinzovia franki sp. nov. (rare), Giumaliceras giumaliense gen. et sp. nov. (abundant), Giumaliceras bhargavai gen. et sp. nov. (rare), Neocomites (Eristavites) platycostatiformis sp. nov. (rare), Cleoniceras oberhauseri sp. nov. (abundant), Australiceras himalayense sp. nov. (rare) and Deshayesites fuchsi sp. nov. (rare). Sinzovia and Deshayesites are reported for the first time from the Tethyan Himalaya. According to the biostratigraphic relevance of some ammonoid taxa described here, the age of the Giumal Formation can be constrained from Berriasian (Giumaliceras assemblage) to Aptian (Cleoniceras assemblage). The discovery of the new fauna substantiates the significance of the Giumal Formation around Chikkim and facilitates comparison with faunal assemblages from other regions in the Tethys Ocean and beyond.  相似文献   

7.
Abstract: Red calcareous Middle Cambrian palaeosols from the upper Moodlatana Formation in the eastern Flinders Ranges of South Australia formed in well‐drained subhumid floodplains and include a variety of problematic fossils. The fossils are preserved like trace fossil endichnia but do not appear to be traces of burrows or other animal movement. They are here regarded as remains of sessile organisms, comparable with fungi or plants living in place, and are formally named as palaeobotanical form genera under provisions of the International Code of Botanical Nomenclature. Most common are slender (0.5–2 mm) branching filaments flanked by green‐grey reduction haloes within the red matrix of palaeosol surface horizons (Prasinema gracile gen. et sp. nov.). Other axial structures (Prasinema nodosum and P. adunatum gen. et spp. nov.) are larger and show distinctive surface irregularities (short protuberances and irregular striations, respectively). The size and form of these filaments are most like rhizines of soil‐crust lichens. Other evidence of life on land includes quilted spheroids (Erytholus globosus gen. et sp. nov.) and thallose impressions (Farghera sp. indet.), which may have been slime moulds and lichens, respectively. These distinctive fossils in Cambrian palaeosols represent communities comparable with modern biological soil crusts.  相似文献   

8.
In the past an ‘explosion’ in diversity and abundance of small shelly fossils and of trace fossils has served to mark the base of the Cambrian. However, no evidence has been presented to prove that the ‘explosions’ of the two groups were synchronous. We describe small shelly fossils and trace fossils from the same phosphatic limestone beds that indicate that the two events were separate in time. The small shelly fossils are Anabarites trisulcatus, Hyolithellus cf. H. isiticus, Microcornus? sp., Protohertzina anabarica, P. unguliformis, P. sp. A, Pseudorthotheca sp. A, Rushtonia? sp. A, four types of tuberculate plates and one type of reticulate plate. These fossils represent a restricted, ‘pre-explosion’ fauna and are assigned to the Anabarites-Circotheca-Protohertzina Assemblage Zone, an uppermost Precambrian zone in the Meishucun Stage, Yunnan Province, China. A point at the top of this zone has received strong international endorsement for future designation as the base of the Cambrian. Associated with the small shelly fossils are the trace fossils Cruziana sp. A, Cruziana? sp. B, Rusophycus sp. A, Palaeophycus rubdark and arthropod scratch marks. If found in isolation, this trace fossil assemblage would be considered as post-Precambrian because it includes large, highly organized arthropod traces that are traditionally accepted as occurring above the trace fossil ‘explosion’. We therefore conclude that the trace fossil ‘explosion’ predates the small shelly fossil ‘explosion’. If the proposed location of the base of the Cambrian in Yunnan is accepted, the small shelly fossil ‘explosion’ concept and its relationship to the boundary would not be greatly modified. The trace fossil ‘explosion’, however, would no longer indicate the base of the Cambrian and the ranges of some trace fossils would be extended into the Precambrian.  相似文献   

9.
Extensive sampling of several Barremian and Albian–Cenomanian levels across the Aguilón, Oliete and Aliaga subbasins of the Iberian Basin, north‐east Spain, yielded abundant material of new or so far poorly known neoselachians. The faunas consist of 16 different species, five of which represent new species and two new genera: Cantioscyllium brachyplicatum sp. nov. , Platypterix venustulus gen. et sp. nov. , Ptychotrygon pustulata sp. nov. , Ptychotrygon striata sp. nov. and Iberotrygon plagiolophus gen. et sp. nov. In addition, teeth of Heterodontus cf. H. carerens, Lamniformes indet., Pteroscyllium sp., Scyliorhinidae indet., Rhinobatos sp., Spathobatis sp., Belemnobatis sp., Ptychotrygon geyeri, Ptychotrygon sp. and Celtipristis herreroi are described. The new family Ptychotrygonidae is defined. The localities comprise palaeoenvironments ranging from lacustrine and shallow lake to open marine settings. Neoselachians are almost completely absent from continental settings in the Barremian, as a result of prevailing freshwater conditions, but became more abundant in marine strata. The Albian–Cenomanian selachian assemblage is the most profuse and diverse of the three assemblages studied. It is dominated by small, benthic and near‐coastal taxa, for instance Cantioscyllium and Ptychotrygon, and contains several new species, including an endemic batoid, Iberotrygon plagiolophus gen. et sp. nov. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 155 , 316–347.  相似文献   

10.
The problematic lizard family Changjiangosauridae, representatives of which inhabited Asia in the Early Paleogene, is discussed. Six new species of this group, including Acrodontopsis robustus gen. et sp. nov., Agamimus gracilis gen. et sp. nov., Graminisaurus interruptus gen. et sp. nov., Khaichinsaurus reshetovi gen. et sp. nov., Lavatisaurus elegans gen. et sp. nov., and Lentisaurus giganteus gen. et sp. nov., from the Middle Eocene of the Khaichin Uul 2 locality (southern Gobi, Mongolia) are described. It is shown that Changjiangosauridae are probably related to the Late Cretaceous Isodontosauridae and recent Uromastycidae; independent development of a number of dental features in different lineages of Acrodonta (Iguania) is corroborated.  相似文献   

11.
12.
本文描述蝎龄化石1新属4新种。新属Megabittacus2新种,即Megabittacuscolosseussp.nov.,Megabittacusbeipiaoensissp.nov,新种Sibirobittacusatalussp.nov.属于现生的蚊蝎蛉科,新种Orthophlebialiaoningensissp.nov.属于绝灭的直脉蝎蛉科。化石采于辽宁省北票市晚侏罗世义县组地层中。这些新的化石属种,其虫体特征包括触角、喙、足和翅脉特征均完整的保存。模式标本保存在中国地质博物馆。  相似文献   

13.
The morphology of two new bivalved arthropods, Loricicaris spinocaudatus gen. et sp. nov. and Nereocaris briggsi sp. nov. from the middle Cambrian (Series 3, Stage 5) Burgess Shale Formation (Collins Quarry locality on Mount Stephen, Yoho National Park, British Columbia, Canada), is described. The material was originally assigned to the genus Branchiocaris, but exhibits distinctive character combinations meriting its assignment to other taxa. Loricicaris spinocaudatus possesses an elongate and spinose abdomen comparable to the contemporaneous Perspicaris and Canadaspis, as well as chelate second head appendages and subtriangular exopods, comparable to Branchiocaris. Nereocaris briggsi possesses a laterally compressed carapace, elongate and delicate appendages and a medial eye located between a pair of lateral eyes on a rhomboidal eye stalk. Although undoubtedly congeneric with Nereocaris exilis from a slightly younger horizon of the Burgess Shale Formation, N. briggsi differs in overall proportions and segment number, warranting assignment to a new species. The newly described taxa were coded into an extensive cladistic analysis of 755 characters, and 312 extinct and extant panarthropods, including a variety of Cambrian bivalved arthropods from both the Burgess Shale and the Chengjiang Lagerstätten. Cambrian bivalved arthropods consistently resolved as a paraphyletic assemblage at the base of Arthropoda. Important innovations in arthropod history such as the specialization of the deutocerebral head appendages and a shift from a nekton‐benthic deposit feeding habit to a benthic scavenging/predatory habit, the symplesiomorphic feeding condition of Euarthropoda (crown‐group arthropods), were found to have occurred among basal bivalved arthropods.  相似文献   

14.
From the Lower Cretaceous locality Khasurty, western Transbaikalia, a new genus and species, Rasnitsyrina culonga, gen. et sp. nov. are described in the family Perlariopseidae. R. desiliens (Sinitshenkova, 1987), originally described in the genus Karanemoura Sinitshenkova, 1987, is transferred to the new genus. Two new species belonging to recent families are described: Dimoula khasurtensis sp. nov. (Nemouridae) and Jurataenionema rohdendorfi sp. nov. (Taeniopterygidae). All new species are described from fossils of adults.  相似文献   

15.
Until now, only two Psychodoidea were known from Lebanese amber. We describe two new genera and species of Phlebotomidae ( Mesophlebotomites hennigi gen. et sp. nov., Libanophlebotomus lutfallahi gen. et sp. nov.) and four new genera with six new species of Psychodidae ( Paleopsychoda solignaci gen. et sp. nov., Paleopsychoda jacquelinae sp. nov., Protopsychoda nadiae gen. et sp. nov., Protopsychoda hammanaensis sp. nov., Libanopsychoda abillamai gen. et sp. nov., Cretapsychoda inexpectata gen. et sp. nov.) from the Lower Cretaceous amber of Hammana/Mdeirij, Lebanon. These fossils are included in a phylogenetic analysis of the subfamilies of Psychodoidea. This superfamily was probably as diverse in the Early Cretaceous as now.  相似文献   

16.
Abstract Two new genera and six new species of Palaeontinidae are named and described: Liaocossus hui gen. et sp. nov., L. beipiaoensis gen. et sp. nov., L. exiguus gen. et sp. nov., L. fengningensis gen. et sp. nov., L. pingquanensis gen. et sp. nov., and Miracossus ingentius gen. et sp. nov., The entire body of these new fossils are perfectly preserved and enable us to fix accurately the body characteristics of primitive palaeontinids. All the specimens were collected from Late Jurassic Yixian Formation of Northern Hebei and Western Liaoning Provinces in China.  相似文献   

17.
New chonetid genera and species Subtilichonetes pamiricus gen. et sp. nov. (subfamily Undulellinae, family Rugosochonetidae) and Parvichonetes igrimiusensis gen. et sp. nov. (subfamily Tornquistiinae, family Anopliidae) are described from the Takhtabulak Formation, Changhsingian Stage of the Upper Permian of Southeastern Pamir.  相似文献   

18.
<正>随着中国经济的持续、稳定发展和国家政府对基础研究的日趋重视,我国科技投入力度正在逐年加大,包括古生物学在内的地球科学基础研究近十年来取得长足的进步和发展。近些年,我国的古生物学已开始在多门类起源、系统演化和环境背景研究中处于国际领先,在部分研究方向开始发挥重要国际引领作用。加之华南、华北保存的化石材料优势和若干国家重大项目的稳定、持续支持(Zhu et al.,2016a;Zhu and Li,2017),使我国在科研队伍、  相似文献   

19.
Adolfia siratschoica (Ljaschenko) and Adolfia krestovnikovi (Ljaschenko) are accepted as zonal species of the Petino and Voronezh Horizons of the Frasnian Stage of the Russian Platform. However it was established that these species do not belong to the genus Adolfia. The former species was recognized as the nomenclatural type species of Ljaschenkovia gen. nov. and the latter species was recognized as the type species of Tokmospirifer gen. nov. The comparative analysis provided of the shell structure, microornamentation, and shell interior of the type species of Ljaschenkovia gen. nov., Tokmospirifer brevis gen. et sp. nov., and Adolfia solita Ljaschenko is presented.  相似文献   

20.
Abstract: A rich, diverse Permian ostracod fauna has been recovered from the red and grey, laminated shales and quartz‐rich shales of the Triassic Lercara Formation. Forty‐seven species have been identified, 13 of which are newly described here; they belong to 26 genera of which three are new: Anahuacia lercaraensis sp. nov., Aurigerites siciliaensis sp. nov., Bairdia portellaensis sp. nov., Cristanaria? katyae sp. nov., Fabalicypris gruendeli sp. nov., Lethiersa salomonensis gen. et sp. nov., Lethiersia sinusoventralis gen. et sp. nov., Portella trapezoida gen. et sp. nov., Siciliella elongata gen. et sp. nov., Siciliella infernespinosa gen. et sp. nov., Siciliella prima gen. et sp. nov., Siciliella quadrata gen. et sp. nov., and Siciliella spinorobusta gen. et sp. nov. The assemblages contain or are composed of palaeopsychrospheric forms, which are regarded as index fossils for deep environments. The bathymetry of the different associations in life is evaluated.  相似文献   

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