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1.
This paper presents eight ephedroid palynomorphs from the Lower Cretaceous (Upper Albian) of Hokkaido, Japan. The ephedroid palynomorphs are ellipsoid and polyplicate pollen grains that show a wide range of variation in pollen size, shape, and plication. These ephedroid palynomorphs suggest a wide range of diversity in Gnetales at mid- or high-paleolatitude in the eastern side of Lauresia during the Upper Albian.  相似文献   

2.
This paper describes dispersed angiospermous pollen grains from the Maastrichtian of Sakhalin, Russia, with scanning electron microscopy. These pollen grains includeClavatipollenites, Tricolpites, andBetulaepollenites. Exine sculpture of the pollen grains are shown in detail. The palynomorphs imply a wide range of angiosperm diversity during Maastrichtian time at the mid- or high-latitudes in the eastern Eurasia.  相似文献   

3.
Fossil plants from the Upper Devonian (Frasnian) of northern Timan are studied. The sporangia contain well-preserved spores, which were studied in transmitted light using a scanning electron microscope. The genus Gutzeitia S. Snigirevsky, gen. nov. is established. Macroremains and in situ spores of G. timanica (Petros.) S. Snig., comb. nov. and ?Cephalopteris mirabilis (Nath.) Nath. are described. Microspores in Dimeripteris gracilis Schmalh. are identified, and microspores and megaspores in ?Cephalopteris mirabilis are studied for the first time.  相似文献   

4.
Summary Rudist and stromatoporid associations of the Campanian from Central Oman are nearly monospecific. They are dominated byDurania aff.nicholasi, Vaccinites vesiculosus, Torreites milanovici or phaceloid and massive stromatoporids. Several other rudist genera play a secondary role. The thickness of the associations is rarely more than one metre. Solitary corals do not occur in the associations. Colonial corals are less common, although they are up to 1 m high and show considerable diversity. There are no binders. The reef structure indicates variable hydrodynamic conditions. They are always associated with very shallow water. The pureDurania aff.nicholasi patches with large colonial corals andTorreites milanovici are presumably the most rigid structures. The near monospecific associations ofVaccinites vesiculosus are widely distributed. Although mostly preserved in situ, strong currents, presumably caused by tropical storms, have repeatedly impaired and interrupted growth. The specific growth characteristics of the shell of some rudists, especially the radiolitids, enable an estimation of the individual lifespan. Frameworks of approximately 1 metre thickness probably developed in ±100 years. The sediments of the complete sections are predominantly bioclastic.  相似文献   

5.
Airborne pollen and spores, as well as airflow directions, were continuously monitored during a cruise across the East Mediterranean from Tel Aviv, Israel, to Istanbul, Turkey. In spite of the fact that a high-altitude dust cloud moved, at that, time from North Africa, across the East Mediterranean, only a few dust particles were monitored on the boat. The numbers of counted airborne pollen along the cruise path were rather small. This is, in part, because the trip was taken after the main flowering season in the East Mediterranean region. Nevertheless, airborne pollen grains were still found, either as a result of remnant pollen releases by late-flowering plants or because of secondary lift-up of previously settled pollen. The presented pollen counts are average pollen counts /m3 air /6 h. The counts ranged between ∼5 pollen/m3 of air in mid-sea (July 16th–July 17th) or ∼6 pollen/m3 of air on the Israeli coast (July 16–July 17th), and 30 pollen/m3 of air near the coasts of Turkey and of the Greek Islands (July 18th–July 19th) and some 18 taxa of pollen were identified, most of them at the family level. Some 30 taxa of different spores were recorded. The numbers of airborne spores were relatively low in mid-sea (300–750 spores/m3 air), but were high near the coasts of Turkey (1,200–2,400 spores/m3 air) and of Israel (340–1,695 spores/m3 air).  相似文献   

6.
in situ spores, and megaspores also document the presence of Selaginellaceae and Schizaeaceae. Received 8 February 1999/ Accepted in revised form 7 April 1999  相似文献   

7.
Cunninghamia asiatica (Krassilov) comb. nov. was an early Cretaceous plant which was widely distributed over North and North-East China and Siberia. It was previously identified as Elatocladus manchurica (Yak.) or Elatides asiatica (Yak.). Present paper combines them into Cunninghamia mainly based on the similarities of the morphological and epidermal characteristics between the fossil species and living Cunninghmia (table 1 and 2), and dates the history of Cunninghamia back to Early Cretaceous.  相似文献   

8.
Middle to Late Cretaceous permineralized plants hitherto described from Hokkaido, Japan are summarized. The fossil flora comprises fungi, ferns, gymnosperms and angiosperms. Many modern fern families have been recognized including Anemiaceae, Cyatheaceae, Dennstaedtiaceae, Gleicheniaceae Loxsomaceae, Lygodiaceae and Matoniaceae. Gymnosperms are most abundant in the flora. Some recently-found materials are tentatively introduced with brief comments emphasizing their morphological and taxonomical significance. A bisporangiate flower ofCycadeoidella japonica Ogura shows fine internal anatomy and provides evidence that the cycadeoidalean ovule was a cupulate, unitegmic structure. Vascular tracheids in the synangial wall support the evolution of cycadeoidalean synangia from Paleozoic seed-fern synangia. A new gymnosperm female fructification has a thick envelope comparable to an angiosperm carpel around a large seed. The angiosperms contain various morphologies that require further extensive study.  相似文献   

9.
A new genus and species of Actinidiaceae (Parasaurauia allonensis gen. et sp. nov.) are established for fossil flowers and fruits from the early Campanian (Late Cretaceous) Buffalo Creek Member of the Gaillard Formation in central Georgia, USA. The fossil flowers, which are exquisitely preserved as charcoal, have five imbricate, quincuncially arranged sepals and petals. The androecium consists of ten stamens with anthers that are deeply sagittate proximally. The gynoecium is tricarpellate, syncarpous, and has three free styles that emerge from an apical depression in the ovary. The fruit is trilocular and contains numerous ovules on intruded axile placentae. The structure of mature fruits is unknown. Comparisons with extant taxa clearly demonstrate that the affinities of Parasaurauia allonensis are with the Ericales, and particularly with the Actinidiaceae, which have been placed among the Ericales in recent cladistic analyses. Because Parasaurauia allonensis is not identical to any one genus of Actinidiaceae, or other member of the Ericales, phylogenetic relationships of the fossil were evaluated through a cladistic analysis using morphological and anatomical characters. Results of this analysis place Parasaurauia allonensis within the Actinidiaceae as sister to the extant genera Saurauia and Actinidia. Parasaurauia allonensis differs from extant Saurauia only in having ten rather than numerous stamens.  相似文献   

10.
Lauranthus futabensis , gen. et sp. nov. is assigned to the Lauraceae based on the regular trimerous organization of the perianth and androecium, and the valvate anthers. It provides the first detailed report of lauraceous flowers from the Cretaceous of Asia and adds significantly to our knowledge of the geographic distribution of Cretaceous Lauraceae and their systematic and structural diversity. Received 11 April 2001/ Accepted in revised form 30 August 2001  相似文献   

11.
A fossil trimerous flower from the Turonian (ca. 90 MYBP, Upper Cretaceous) of New Jersey is described as a new genus in the familyLauraceae. The fossil flower is charcoalified and preserved in exceptional detail. This fossil specimen is particularly remarkable in that several pollen grains have been preserved; pollen grains ofLauraceae generally have very thin exine and are rarely preserved in the fossil record. Although the specimen is incomplete and lacks anthers, there are sufficient structural details preserved to permit an assignment to theLauraceae, as well as comparisons with the tribePerseeae. This new genus provides an important addition to our knowledge of systematic and structural diversity in CretaceousLauraceae.  相似文献   

12.
A new genus ( Protosciadopityoxylon gen nov. ) of Early Cretaceous fossil wood reported in the present paper was discovered from Liaoning Province, China, and is named as a new species:Protosciadopityoxylon liaoningense gen. et sp. nov. It is described here and this generic name, adopted by the authors, is employed for fossil wood that is believed to be nearly related to the recent genus Sciadopitys and the fossil genus Sciadopityoxylon. The new genus bears some similarities to Protophyllocladoxylon,Protocircoporoxylon and Xenoxylon in different geological ages, but it differs from them in the types of cross-field pitting.  相似文献   

13.
Aerobiological study of fungal spores from Palencia (Spain)   总被引:2,自引:2,他引:0  
A study of the concentration of fungal spores has been carried out in the atmosphere of Palencia town (NW Spain) during 1992. The volumetric method of filtration has been used. Half of the daily filter sample has been cultivated in Czapecdox-agar or Sabouraud-agar for the identification of fungal colonies, and the other half has been examined by optical microscopy. Several colonies belonging to 26 genera have been identified. Deuteromycetes (54%) and Zigomycetes (28%) are assembled in four genera, and Bacteria and Actynomycetes (18%) in three genera. The greatest concentrations occur forAspergillus (23%),Mucor (25%), followed byPenicillium (16%). The greatest diversity and abundance of fungal spores are found in September–December. The viable colonies are more abundant in Czapedox-agar culture, whereas Bacteria were more frequently found in Sabouraud medium.  相似文献   

14.
One inaperturate and 16 monosulcate pollen types are described from the latest Campanian to earliest Maastrichtian sediments of the Vilui basin, Siberia, using both light and scanning electron microscopy, and assigned systematically when possible to modern families or subfamilies. Despite their scant occurrence, the pollen grains show considerable diversity. Two new genera have been erected. Lasioideaecidites with two species, Lasioideaecidites hessei and Lasioideaecidites bogneri, represents the earliest record of the subfamily Lasioideae (Araceae). Aristolochiacidites with one species, Aristolochiacidites viluiensis, is assigned to the subfamily Aristolochioideae (Aristolochiaceae) and represents the first fossil pollen record of the family. A new species of Liliacidites, Liliacidites goldblattii, is closely similar to pollen of Isophysioideae (Iridaceae) and/or Doryanthaceae and is the first fossil evidence of the clade that includes these closely related families. A further nine new fossil species are described (Clavatipollenites timerdyakhensis, Liliacidites palaeofritillaria, Retimonocolpites longosucatus, R. microreticulatus, R. microrugulatus, R. lysichitonoides, R. chapmaniae, Monosulcites parvus and Arecipites tyungensis) and assigned to Chloranthaceae, Araceae (Orontioideae, ?Pothoideae), Liliaceae, ?Hypoxidaceae and Arecaceae. The Hydatellaceae (Nymphaeales) may also be present in the palynoflora of the Vilui Basin, represented by pollen similar to M. rivularis Braman from the Santonian to Campanian (Upper Cretaceous) Milk River Formation, Canada.  相似文献   

15.
The Coriolis δ air sampler manufactured by Bertin Technologies (France) is a continuous air sampler, dedicated to outdoor monitoring of airborne spores and pollen grains. This high-volume sampler is based on patented Coriolis technology delivering a liquid sample. The air is drawn into a conical vial in a whirling type motion using suction; particles are pulled against the wall by centrifugal force. Airborne particles are separated from the air and collected in a liquid medium. This innovative solution allows rapid analysis by several techniques including PCR assay and serological assay in order to measure the antigenicity/allergenicity of pollen grains and fungal spores. Also, traditional counting of pollen grains or taxa identification by optical microscopy can be done. A study has been carried out by the Health Protection Agency (HPA), Porton Down, UK, to measure the physical efficiency of the Coriolis air sampler. The physical efficiency of the sampler for collection of micro-organism-laden particles of various sizes has been compared with that of membrane filter samplers using the techniques described by ISO 14698-1. The Coriolis was operated simultaneously with membrane filter samplers in a controlled room where they were challenged with uniform-sized particles of different diameters containing bacterial spores. For the larger particle sizes, it was found that the physical efficiency of the Coriolis was 92% for 10-μm particles. The biological performance of the Coriolis in the collection of airborne fungal spores and pollen grains was evaluated in comparison with a Hirst spore trap (one-week tape-on-drum type sampler) which is one of the most frequently used traps in the measurement of outdoor pollen grain concentrations. The advantages and limitations of both technologies are discussed. The Coriolis was operated simultaneously with a Hirst spore trap in the sampling station of Réseau National de Surveillance Aérobiologique, France (RNSA); the pollen grain and fungal spore counts were analysed by optical microscopy. The pollen grain count m−3 collected was compared for both devices. The dispersion values were obtained and statistical analysis was carried out. This study shows that the Coriolis air sampler provided equivalent recovery of pollen grain and fungal spores compared with the volumetric trap standard method (not significantly different, W test, α = 0.05). Nowadays, the French-led project, acronym MONALISA, with financial support from the European Commission––Life-Environment (LIFE05 ENV/F/000068), is testing this innovative air sampler in order to measure the antigenicity/allergenicity of the main aeroallergen particles, i.e. Betula (birch), Poaceae (grasses), Parietaria (pellitory), Olea spp (olive tree), and Artemisia (mugwort) pollen grains, and Alternaria (fungal spores) to validate a new approach of monitoring instead of quantifying pollen grains by their morphology. The robustness and efficiency of the MONALISA system is being demonstrated at a national level throughout Europe in eight different countries with different bio-climatic and topography characteristics: France, UK, Finland, Poland, Spain, Portugal, Switzerland, and Italy.  相似文献   

16.
Study of several marine Santonian-Campanian successions from Sakhalin Island, Far East Russia, has revealed that evolution of the ammonites and inoceramid bivalves proceeded at different rates after the major faunal turnover at the (locally defined) Santonian-Campanian boundary. Sometimes changes in the inoceramid assemblages were more frequent and rapid than changes in the ammonite assemblages, and sometimes vice versa. Significant levels of inoceramid turnover and radiation events have been identified at the (locally defined) Santonian-Campanian and lower-upper Campanian boundaries. Changes in ammonite and inoceramid diversity, and in the proportions of endemic and cosmopolitan species, were investigated in the context of the local relative sea-level curve and inferred environmental changes. In Far East Russia, the main ammonite and inoceramid radiation after the local Santonian-Campanian faunal turnover occurred in the early Late Campanian Pachydiscus (P.) aff. egertoni ammonite Zone and the coeval Schmidticeramus schmidti inoceramid Zone. This condensed interval of ammonite and inoceramid maximum diversity provides a perfect stratigraphic marker that is recognizable in Sakhalin, North-East Russia and Japan. The succession of Santonian-Campanian assemblages identified in Sakhalin enabled the establishment of seven ammonite and six inoceramid zones, which correlate relatively well with those of North-East Russia and Japan. The problems of placing the Santonian-Campanian boundary in Sakhalin and in the adjacent Japanese island of Hokkaido are reviewed.  相似文献   

17.
The Lower Cretaceous Ilek Formation in Western Siberia (Russia) has yielded various vertebrate fossils, including skeletal remains of dinosaurs. Here we report on a fragmentary theropod egg from the vertebrate locality Shestakovo 3 of the Ilek Formation in Kemerovo Province. We assign the specimen to the oogenus Prismatoolithus (oofamily Prismatoolithidae) as Prismatoolithus ilekensis oosp. nov., on the basis of the following unique combination of characters: ovoid-shaped egg; thin eggshell 300–330 μm thick; angustiprismatic morphotype; eggshell with three different layers; gradual transition between mammillary layer and prismatic layer; abrupt contact between prismatic layer and external layer; mammillary layer to prismatic layer to external layer thickness ratio is 1:3:0.6; prismatic layer with ill-defined squamatic texture; angusticanaliculate pore system; and smooth outer surface. Like other Early Creataceous Prismatoolithus, the egg of Prismatoolithus ilekensis oosp. nov. was laid by a small bodied theropod dinosaur (troodontid or primitive bird) and this taxonomic attribution is supported by results of our phylogenetic analysis. Prismatoolithus ilekensis oosp. nov. is the first Early Cretaceous ootaxon from Russia.

urn:lsid:zoobank.org:act:734EAD40-86C3-488B-A61E-B5FF7378BC0E  相似文献   


18.
Summary A study of concentration of airborne pollen grains and fungal spores has been carried out in Barcelona (Spain) during 1989–90. The volumetric method of filtration, previously described for airborne pollen analysis (Suarez-Cervera and Seoane-Camba, 1983) has been used. In this case, the filters have also been cultivated in Czapecdox-agar, Sabouraud-agar and Sabouraud-agar with streptomycin for the identification of the fungal colonies. Analysis of the number of fungal spores growing on the filter shows that the maxima of colonies of spores developed in culture per m3 of air filtered, correspond to September–December. Pollen and spore concentrations start from November–December, reach a maximum in March–April and decline progressively until September–October. Therefore, in the city of Barcelona, the greatest concentration occurs in spring and the lowest in autumn.  相似文献   

19.
The applicability of p-coumaric acid and ferulic acid concentrations or ratios in (sub)fossil plant remnant as UV-B proxies relies on various aspects, which are discussed in this paper and will be illustrated with some experimental data. A newly developed THM-micropyrolysis–gas chromatography–mass spectrometry method was tested on various spores, pollen and other plant remains, which were analysed for the presence of the UV-absorbing compounds p-coumaric acid and ferulic acid. This revealed that these supposed building-blocks of sporopollenin appear to be present in pollen of many plant species but also in moss spores. The development of this micropyrolysis method paved the way for the quantitative analysis of UV-absorbing compounds in case only a small amount of analyte is available, for example for fossil pollen and spores but also other small palynomorphs and plant fossils. The use of this technique will provide a better insight in the plant responses to UV-radiation, the chemistry of pollen and spores, their fossil counterparts and furthermore the means for a further development of a proxy for the reconstruction of past UV-B radiation.  相似文献   

20.
Microfossils which matchLactoris (Lactoridaceae) pollen more closely than those of any other living angiosperm occur in Campanian to Paleogene sediments around the margins of Australia. These are referred to the fossil genus Lactoripollenites (Zavada & Benson 1987). A species belonging to the same genus occurs in older (Turonian-Santonian) deposits off southern Africa but Australian specimens represent not only the most southern, but also the youngest known (Oligocene) records to date. Our data support suggestions that theLactoridaceae were widespread across the Southern Hemisphere during the Late Cretaceous (Lammers & al. 1986,Zavada & Benson 1987). An homology between gymnosperm sacci and the saccus-like structures found in Lactoripollenites and some specimens ofLactoris pollen is contested, as is the use of (anasulcate) apertures to support the primitive position of the family.  相似文献   

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