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1.
Catfish bones from Tortonian (Miocene) freshwater beds of central Argentina are here identified as pertaining to a new species of the tropical pimelodid genus Phractocephalus. The new species differs from the other recent and fossil species of the genus in skull, pectoral girdle and spine characters. The material was found in different localities near the city of Paraná, Entre Ríos Province. The bearing horizon is the so-called “Conglomerado osífero” which constitutes the lowermost beds of the fluvial Ituzaingó Formation. The aquatic vertebrate fauna occurring in the bearing bed shows a similar generic composition to several northern South American Miocene units where Phractocephalus remains were found. This report extends the range of Phractocephalus more than 2000 km to the South. The record is in agreement with higher global temperatures and putative ample hydrographic connections of the river basins in the Paraná area with the Amazon basin until at least the early late Miocene.  相似文献   

2.
Teeth of a new species of hybodont shark Vectiselachos (Chondrichthyes: Lonchidiidae) are described from the late Aptian (Early Cretaceous) of southern England. Vectiselachos gosslingi sp. nov. has very distinctive coarse striations that form raised ridges over the occlusal surfaces of the crown.  相似文献   

3.
A new Upper Cretaceous genus and species of soldier beetles, Archaeomalthodes rosetta gen. et sp. nov., is described and illustrated from an individual preserved in Upper Cretaceous (Cenomanian, ca. 99 Ma) amber from northern Myanmar. It is undoubtedly placed in extant subfamily Malthininae based on its small-sized body, somewhat abbreviated elytra and fusiform terminal maxillary palpomere, representing the oldest documented occurrence of Malthininae. It suggests that this subfamily is an ancient group, which originated at least in the earliest Late Cretaceous. Our discovery sheds light on the palaeodiversity of Cantharidae in the Late Mesozoic. Together with other previously reported fossil cantharids, it is likely that Malthininae has been fairly diverse during the early evolution of Cantharidae. On the other hand, a morphological similarity between Archaeomalthodes and Recent malthinines and the occurrence of flowering plants in the Burmese amber implies a potential flower-visiting behaviour of this fossil species.  相似文献   

4.
A taxon of the Stenophlebiidae, Yixianstenophlebia magnifica gen. et sp. nov., is described from the Lower Cretaceous Yixian Formation at Liutiaogou, Ningcheng County, Inner Mongolia of China. Its closest relative is the Late Jurassic European genus Stenophlebia. This new discovery is helpful to understand the Jehol Biota assemblage at Liutiaogou Locality. It also confirms that the Stenophlebiidae was a very diverse and widespread family during the Early Cretaceous. The causes of its extinction in the Late Cretaceous remain enigmatic.  相似文献   

5.
A new genus and species, Similinannotanyderus lii gen. et sp. nov., is described from Myanmar amber. It differs from other genera of Tanyderidae based on special characters of wing venation and male genitalia. This new taxon broadens the diversity of Tanyderidae in the Cretaceous, and its morphological characters enhance our understanding of the development and evolution of the primitive crane flies.  相似文献   

6.
A new polypore fungus beetle is described and illustrated, under the name of Thescelostrophus cretaceus gen. et sp. nov., representing the first documented occurrence of the tribe Eustrophini. The well-preserved specimen was collected from the Upper Cretaceous (Cenomanian, ca. 99 Ma) amber near the Hukawng Valley of northern Myanmar. This fossil species can be assigned to the extant subfamily Eustrophinae based on its elongate oval and strongly narrowed posteriorly body, simple and narrow tarsi, and somewhat clubbed antennomeres. The comparison among the extinct and extant eustrophines supports the previous hypothesis that antennal morphology of early eustrophines was very diverse. Additionally, an overall similarity between Thescelostrophus and extant eustrophines suggests a potential fungivory of this fossil species. Morphological characters preserved in the Burmese amber highlight the diversity of tetratomids during the Late Mesozoic and provide data for future phylogenetic studies of Tetratomidae.  相似文献   

7.
A new genus and species of ripiphorid beetle is described based on a female specimen preserved in Upper Cretaceous (Cenomanian, ca. 99 Ma) amber from northern Myanmar, under the name of Spinotoma ruicheni gen. et sp. nov. It belongs to the extant Pelecotominae and represents the second documented occurrence of this subfamily in the Late Cretaceous. This new taxon is morphologically distinguishable in Pelecotominae by the combination of following characters: eyes oval, without incision; antennomeres V–X serrate, with XI fusiform; maxillary palpi unmodified; protarsi shorter than protibiae; tibiae sparsely provided with spines; tibial spurs formula 2-0-2. Together with other previously reported fossil ripiphorids, it highlights the species diversification of wedge-shaped beetles during their early evolution. On the other hand, a morphological similarity between Spinotoma and modern pelecotomines and the occurrence of xylophagous beetles in the Burmese amber suggest a similar host preference in wood-boring beetles for this species, shedding lights on an ancient host-parasitoid relationship in the late Mesozoic. This paper also provides a brief discussion on the taxonomy and evolution of Mesozoic wedge-shaped beetles. The wedged-shaped body form and fully-developed elytra in Recent Pelecotominae and Ptilophorinae are considered to be derived from their early ancestors rather than evolved with the onset of flowering plants during the Cretaceous as commonly thought.  相似文献   

8.
The sedimentary cycles of the Cenomanian to Maastrichtian were investigated in the Basco-Cantabrian Basin (BCB) in northern Spain (Provinces of Alava, Vizcaya and Burgos). The depositional area was a distally steepened carbonate ramp which extended from Catalonia northwestwards to the Basque country. The investigated sediments range from calciturbidites and pelagic marls to marl-limestone alternations deposited on a distal carbonate ramp. Shallow marine limestones, marls and intertidal clastics and carbonates were deposited on the proximal part of the carbonate ramp. The establishment of a regional sequence analysis is based on the investigation of seismic profiles, well logs and outcrop sections. Examples of outcrop sections are interpreted in terms of sequence stratigraphy (unconformities of third- and second-order cycles, depositional geometries, systems tracts). The sequence stratigraphic interpretation of outcrop sections is based on facies analysis, interpretation of observed depositional geometries and correlation of unconformities and marine flooding surfaces through the basin. A biostratigraphic framework is established based on ammonites, inoceramids, planktonic and benthic foraminifera. As a result, a regional sequence stratigraphic cycle chart is presented and compared with published global cycle charts. The correlation of the regional cycle chart with published cycle charts is good. In the Cenomanian and Turonian, several sequence boundaries in the BCB are shifted by up to one biozone compared with the global chart. Some type 1 boundaries of the standard chart are only type 2 in the BCB. Important type 1 boundaries in the BCB are: top Geslinianum Zone with a 100 m lowstand wedge at the basis of the sequence (sequence boundary 92.2) ; base Petrocoriense Zone with a 250 m shallowing-upwards lowstand wedge at the basis (sequence boundary 89.2); and within the Syrtale Zone (sequence boundary 85.0).The Campanian-Maastrichtian sequence record is strongly disturbed by local compressive tectonics. Several sequences are recognizable and can be correlated with the global cycle chart. Correlation is hampered by the low biostratigraphic resolution in the western basin part. Subsidence analysis of several sections of the Upper Cretaceous of the BCB and its interpretation in the regional tectonic context leads to a discussion of the causes of the observed cyclicity. A regional eustatic curve is presented for the Upper Cretaceous of the BCB. Stage and substage names were used according Code-Committee (1977). Correspondence to: K.-U. Gräfe  相似文献   

9.
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   

10.
11.
A new fossil species of Cyrtophyllitinae, Vitimoilus ovatus sp. nov., is described from the Dabeigou Formation and Yixian Formation of the Lower Cretaceous of China. It is clearly placed in Vitimoilus Gorochov, 1996 according to the following characters: R forking into RA and RP distally, M forking into MA and MP distally; CuA fused with CuPaα distal of the middle of the wing length; cross-veins in basal part of CuPb–CuPaβ area non-strongly curved.  相似文献   

12.
13.
The stratigraphic division and sequence of the Upper Cretaceous sediments in eastern Heilongjiang Province,China,have been ambiguous and controversial,mainly due to a lack of biostratigraphically useful fossils and related radiometric dating.A new species of angiospermous fossil plant.Platanus heilongjiangensis sp.nov.,from Qitaihe in eastern Heilongjiang has been found in sediments conformably above which zircons from a rhyolitic tuff has been dated by U-Pb radiometric methods as 96.2± 1.7 Ma.indicating that the Upper Houshigou Formation is of Cenomanian age.This discovery not only provides new data to improve our stratigraphic understanding of the Houshigou Formation,but also shows that Platanus flourished in the early Late Cretaceous floras of the region.This new study also indicates active volcanism taking place in the eastern Heilongjiang region during the Cenomanian of the Late Cretaceous.  相似文献   

14.
The biserial planktonic foraminiferal species Heterohelix striata (Ehrenberg)has been analyzed by morphometric techniques from six sequential late Maestrichtian core samples from southern Sweden and one sample from the Daniaquarry of Denmark. The study is based on measurements of number of chambers, size of test (length, width, and thickness),marginal angle, and chamber sizes. In addition, prolocular and apertural sizes were analyzed in the Daniaquarry sample. The study includes analyses of the ontogenetic development of the tests, stratigraphic variation in size and shape, intrasample variability, and relationship between gross morphology of the test and prolocular and apertural dimensions.  相似文献   

15.
The Family Afrograptidae is a ‘conchostracan’ group with multiple radial costae reaching to the umbo on their carapaces. It comprises four described genera: Afrograpta, Camerunograpta, Congestheriella and Graptoestheriella with a total of thirteen described species which are occasionally reported from the Jurassic and the Cretaceous in Africa, Europe and South America (i.e. Afrograpta from the Upper Cretaceous of Cameroon; Camerunograpta from the Jurassic to Cretaceous of Cameroon; Congestheriella from the Jurassic to Upper Cretaceous of the Congo Basin, Brazil, Bulgaria, Venezuela and Argentina; and Graptoestheriella from the Upper Jurassic to Lower Cretaceous of Brazil). A new genus and a new species, Surreyestheria ockleyensis gen. et sp. nov., belonging to the Family Afrograptidae from the Lower Cretaceous (lower Barremian) Upper Weald Clay Formation of Ockley Village, Surrey County, southern England is described in this paper. The new genus mainly differs from the other four genera by the special reticulate ornamentation on its carapace. It indicates that the Family Afrograptidae was more diverse and more widely distributed in the late Mesozoic than previously supposed. Afrograptidae is a special branch of Estheriellina the latter originating in the late Palaeozoic and the former in the early Mesozoic. Afrograptids, as a whole had been widespread across Pangea in the Early Jurassic.  相似文献   

16.
A third genus and species of fossil pygidicranid earwigs from Burmese amber is described and figured as Stonychopygia leptocerca Engel, Huang, Thomas, and Cai, gen. et sp. nov. (type species of Stonychopygia Engel and Huang, gen. nov.; Stonychopygiinae Engel and Huang, subfam. nov.). Stonychopygia have features similar to the subfamily Echinosomatinae such as the combination of shorter, subequal second and third flagellomeres and femora that are neither compressed or keeled. However, the new fossil species differs from echinosomatines in many details, particularly the slender form, head longer than wide, slender scape, slender and elongate forceps, and absence of stout, short bristles over the integument. The new fossil is compared with its contemporaneous and modern relatives, and comments are provided regarding the classification of Pygidicranoidea, with the genus Haplodiplatys Hincks removed from Diplatyidae to Haplodiplatyidae Engel, fam. nov.  相似文献   

17.
Abstract

Biostratigraphical data using larger foraminifera and planktonic foraminifera permitted us to establish the correlation between shallow platform sediments rich in larger foraminifera (Montsec and Serres Marginals thrust sheets) and deeper ones containing planktonic foraminifera (Boixols thrust sheet).

Consequently, the Santa Fe limestones containing Ovalveolina-Praealveolinaassemblage represent the Cenomanian. Early Turonian ( ‘IT~ archaeocretacea and P. helvetica zones) exist in both, Montsec and Boixols thrust sheets and it is constituted by Pithonella limestones. Late Turonian (M. schneegansi zone) is only present in Boixols thrust sheet (Reguard Fm.), the Montsec thrust sheet having an erosive hiatus.

Late Coniacian-Early Santonian (D. Concavata zone) is represented in the Montsec thrust sheet (Cova Limestones) and in the eastern part of the Boixols thrust sheet (St. Corneli Fm.) by two differents facies giving two different microfaunal assemblages; the firts one, characterized by Ophtalmidiidae s.l indicate a restricted lagoonal environment while the second one, characterized by diverses species of complex agglutinated, Fabulariidae, Meandropsinidae and Rotaliidae, represents an open shallow platform. In the Boixols thrust sheet (Anseroles Fm.) dominate the planktonic foraminifera and small benthic.

In the late Santonian (D. asyrnetrica zone) the sea reached as far as Serres Marginales thrust sheet where sediments (Tragó de Noguera unit) are terrigenous and deposited in a very shallow platform. In the Montsec thrust sheet (Montsec marls) the larger foraminifera indicate a platform deeper than that of the Serres Marginals thrust sheet. In the Boixols thrust sheet the sediments are deposited in an outer platform (Herbasavina Fm.) or turbiditic basin (Mascarell Mb.).

During Campanian times the transgresion reaches the maximum. In the Serres Marginals sediments are deposited in a restricted shallow environment rich in Meandropsinidae (Serres Limestones). In the Montsec thrust sheet they are deposited in a platform with patch reefs and shoals (Terradets limestones) and in the Boixols one in an outer platform, talus and/or basin.

During Early Maastrichtian times (C. falsostuarti zone) terrigenous materials arrived in the basin, the rate of sedimentation increased outstripping the subsidence rate and the retreat of the sea to the north. Late Maastrichtian (C. gansseri zone) is only present in the Boixols thrust sheet.  相似文献   

18.
In the basal interval, sedimentary cover of the Arakapas ophiolite massif (southern Cyprus) is composed of metalliferous sediments of the Perapedhi Formation that is divided into three sequences based on diverse radiolarian assemblages. These are basal umbers of the Cenomanian age presumably (2–20 m), interlayering cherts and umbers of the Turonian-Coniacian (6–10 m), and opoka-like cherts of the Coniacian-Santonian. Higher in the succession, there are olistostrome deposits of the Moni Formation, which unconformably rest on the eroded underlying strata. In this formation also divisible into three sequences, the lower one 200 to 300 m thick is composed of variegated, presumably Campanian silty clays containing olistoliths of basic, presumably Upper Triassic volcanics, Lower Cretaceous sandstones, and opoka-like cherts and cherty limestones of the Albian-lower Cenomanian. Next sequence (100–200 m) is represented by alternation of variegated silty and green bentonitic clays of the Campaian, which enclose frequent olistoliths and horizons of fine-clastic olistostrome breccias. The upper sequence of upper Campanian-lower Maastrichtian bentonitic clays (50–100 m) contains interlayers of ash tuffs and clayey cherty sediments. Carbonate deposits of the upper Maastrichtian-Paleogene, conformably overlie the Moni Formation.  相似文献   

19.
The rhagionid Lebanoleptis huangi gen. et sp. nov. is described from the Lower Cretaceous amber of Lebanon. It is characterized, illustrated, and compared with the recent and fossil genera having the same particular absence of wing vein M3. Other Mesozoic flies with similar venation and currently attributed to the Rhagionidae are briefly discussed and should be revised.  相似文献   

20.
A new fossil soldier beetle Myamalycocerus vitalii gen. et sp. nov., is described and illustrated from an inclusion in Upper Cretaceous Burmese amber (Myanmar). It differs from all extant genera that have elytra adorned with small striae by possessing raised punctation, very probably an ancient character as it is absent among current species. It differs from the fossil Ornatomalthinus Poinar et Fanti, by the long elytra and relief points which are less raised and more numerous. This new genus appears vaguely related (not necessarily phylogenetically) to the current genus Lycocerus Gorham.  相似文献   

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