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1.
Ammotragus europaeus: a new species of Caprini (Bovidae, Mammalia) from the Early Pleistocene site of Vallonnet (France). A new species of the genus Ammotragus is described from the assemblage III of Vallonnet cave (Roquebrune-Cap-Martin, Alpes-Maritimes, France). These remains were interpreted as Ovis, but the re-study of the dental collection from the site and a first study of a partial braincase with the basal internal region of the horn-core pedicels, the parietals, the temporals, and the basisphenoid bones, show anatomical differences with the Caprini genera Ovis, Capra, and Hemitragus and the Ovibovini genus Soergelia. At the opposite, anatomical similarities of the Vallonnet material to the extant North-African Caprini genus Ammotragus are observed. The age of Vallonnet cave is dated by palaeomagnetic techniques at about 1.0 Ma. Teeth remains similar to the Vallonnet species have been found at Fuente Nueva-3 (Orce, Andalusia, Spain). To cite this article: P.-É. Moullé et al., C. R. Palevol 3 (2004).  相似文献   

2.
A new species of Hyaenidae, Hyaenictitherium minimum, is described in the carnivore fauna of the Late Miocene layers of Toros-Menalla (Chad). Its size is similar to that of a jackal and it had probably a similar ecological niche. It is found in several fossil-bearing localities of this area. The genus Hyaenictitherium is known from the early Late Miocene in Eurasia from China to Spain; the Chadian material is, perhaps with some specimens from Sahabi and Lothagam, the earliest occurrence of the genus in Africa. It results certainly from Eurasian migration, which will have to be taken into account for the analysis of the bulk of the fauna. To cite this article: L. de Bonis et al., C. R. Palevol 4 (2005).  相似文献   

3.
Fossil teeth and bones of aardvarks are relatively common at Langebaanweg, an Early Pliocene site in western Cape Province, South Africa. The remains are compatible in size and most details of morphology to extant Orycteropus afer, and are the earliest fossils attributed to this species. Other Late Miocene to Early Pliocene localities in Africa have yielded smaller species of aardvarks, suggesting that the extant lineage evolved in southern Africa. Morphologically the genus Orycteropus has been remarkably conservative since at least the Early Miocene but it witnessed an overall increase in size through the Neogene. The species O. afer has been morphometrically stable since the Early Pliocene. These observations indicate that the evolutionary process in aardvarks is extremely bradytelic. To cite this article: M. Pickford, C. R. Palevol 4 (2005).  相似文献   

4.
This article reports a new record of the greater noctule Nyctalus lasiopterus (Schreber, 1780) in the Late Pleistocene of Europe. A fragment of a left mandible from this species was collected in Layer O (around 55 ka) from the Abric Romaní rock shelter, providing evidence of the presence of the greater noctule in north-eastern Spain during the latest Late Pleistocene. The relevance of this new record, which is geographically not reported up to now in the area, is discussed in terms of environmental changes.  相似文献   

5.
The first results of a study of dictyostelid diversity in soils of Mediterranean vegetation are presented. Surface soil samples were collected during 2003–2004 from different Mediterranean forests in Spain and Portugal and were plated out for cellular slime moulds. Isolated during this study were 14 species of dictyostelids. One species, Dictyostelium firmibasis is reported for the first time from Europe, and nine (Dictyostelium aureo-stipes, Dictyostelium sp. 1, Dictyostelium fasciculatum, Dictyostelium giganteum, Dictyostelium implicatum, Dictyostelium leptosomum, Dictyostelium sphaerocephalum, Polysphondylium candidum, Polysphondylium pallidum) are new records for the Mediterranean region. Members of the three genera Dictyostelium (ten species), Polysphondylium (three species) and Acytostelium (one species) are present in this region of the world. Comments on their diversity and distribution are included.  相似文献   

6.
We determined the faunal composition and total number of tests (#/g) of planktic foraminifera (> 125 μm) in core KH00-05 GOA 6 near Oman in order to decipher monsoon-induced variability of oceanographic productivity in the open-ocean upwelling area in the northwest Arabian Sea. The core contains a continuous record of sedimentation over the last 230 kyr, with the age model based on oxygen isotope and accelerator mass spectrometry 14C dates. We focused on species (Globigerina bulloides and Globigerinita glutinata) typical for SW monsoonal upwelling and species typical for NE monsoon conditions (Neogloboquadrina incompta, Neogloboquadrina dutertrei, Globigerinoides ruber, and Globigerinoides sacculifer). The changes in relative abundance of these monsoonal indicators suggest that the open-ocean upwelling area was dominated by the SW monsoon during interglacial periods, but by the NE monsoon during glacial periods.Increases in total test abundance during glacial periods confirmed that the NE monsoon rather than SW monsoon contributes largely to planktic foraminiferal productivity in this area. We argue that three types of circumstances resulted in high productivity, with nine high productivity events occurring at a 23-kyr frequency. The first type caused high productivity events at 102 and 199 ka (interglacial periods), characterized by the dominance of upwelling species, indicating high productivity during strong SW monsoons, correlated with high July insolation at 45° N. An exceptional high productivity event occurred at 37 ka during interglacial marine isotope stage (MIS) 3, with contributions from both SW and NE monsoons. The second type of high productivity event occurred at 61, 147, and 175 ka, during glacial periods, characterized by dominance of NE monsoon species, and correlated with low January insolation at 45° N. In addition, a high productivity event at 85 ka (interglacial period) also was induced by enhanced NE monsoons. The last two high productivity events occurred during transitional periods from glacial to interglacial (MIS 6/5.5 and 2/1), were characterized by the replacement of NE monsoon species with upwelling species, and corresponded to abrupt climate warming, suggesting that they are related to both accelerated SW monsoon systems and reduced NE monsoon systems.  相似文献   

7.
8.
Nematode-trapping fungi are ubiquitous in terrestrial habitats in dung, soils, litter and woody debris and they also occur in freshwater, but only one species has been found in marine habitats. The purpose of this study was therefore to investigate whether nematode-trapping fungi occurred in mangrove habitats. To achieve this we assessed the diversity of nematode-trapping fungi on decaying litter from mangroves, freshwater and terrestrial habitats (22 sites) in Hong Kong. Composite samples (n = 1,320) of decaying litter (wood and leaves) were examined and a total of 31 species of nematode-trapping fungi belonging to four genera, Arthrobotrys, Monacrosporium, and Dactylella were recorded. Twenty-nine species reported in this study are new records for Hong Kong and 16 species are new records from mangrove habitats worldwide. Nematode trapping fungi are therefore present in marine environments. Commonly encountered taxa were Arthrobotrys oligospora and Monacrosporium thaumasium which are abundant in all habitats. A. oligospora, M. thaumasium and Arthrobotrys musiformis were frequent (> 10%). Twenty-six species were rare (0.16–9.32%). Species richness and diversity was higher in terrestrial than in freshwater and mangrove habitats (ANOVA, < 0.001). A higher mean diversity was observed on decaying leaves as compared to decaying wood in all habitats (< 0.001). Based on Shannon diversity index, it was also observed that taxa characterized by adhesive nets were more frequent in all habitats. This can be explained by the fact that these taxa may have a better competitive saprotrophic ability which would allow them to compete favourably in nutrient limited environments. Abiotic factors that could be linked to differences in species diversity between decaying wood and leaves are also discussed.  相似文献   

9.
Abstract: All known etyid crabs (Crustacea, Decapoda) from the upper Albian – lower Cenomanian Aldoirar coralgal‐dominated patch reef (Albeniz Unit, Eguino Formation), as exposed at the disused Koskobilo quarry in Navarra, northern Spain, are described, discussed and illustrated. A new species, Xanthosia koskobiloensis, the first member of the genus on record from southern Europe, is erected, and a variety that appears closely related to this, Xanthosia cf. X. koskobiloensis, is recognised. This new taxon could be a forerunner of the early Palaeocene (Danian) Xanthosia gracilis from Fakse (Sjælland, eastern Denmark), with which it shares a morphologically closely similar carapace. On the basis of a revised overview here of all species assigned to it, the genus Xanthosia may have evolved in an environment dominated by deposition of siliciclastics, rather than chalks. In addition, Etyxanthosia fossa has been collected at Koskobilo, and as the distribution of all known specimens demonstrates, E. fossa inhabited various environments. Another new species, Caloxanthus paraornatus, is closely similar as well to a species from Fakse, Caloxanthus ornatus, and constitutes the first record of the genus for southern Europe.  相似文献   

10.
Changes in leaf mass per area (LMA), nitrogen content on a mass-basis (Nm) and on an area basis (Na) with relative irradiance were assessed in leaves of eight temperate species harvested at different depths in a canopy. Relative irradiance (GSF) at the points of leaf sampling was estimated by hemispheric photographs. There was a strong species-dependent positive relationship between LMA and GSF for all species. Shade-tolerant species such as Fagus sylvatica showed lower LMA for the same GSF than less tolerant species as Quercus pyrenaica or Quercus petraea. The only evergreen species in the study, Ilex aquifollium, had the highest LMA, independent of light environment, with minimum values much higher than the rest of the broad-leaved species studied. There was no relation between Nm and GSF for most species studied and only a very weak relation for the relative shade-intolerant species Q. pyrenaica. Within each species, the pattern of Na investment with regard to GSF was linked mainly to LMA. At the same relative irradiance, differences in Na among species were conditioned both by the LMA–GSF relationship and by the species Nm value. The lowest Nm value was measured in I. aquifollium (14.3 ± 0.6 mg g–1); intermediate values in Crataegus monogyna (16.9 ± 0.6 mg g–1) and Prunus avium (19.1 ± 0.6 mg g–1) and higher values, all in a narrow range (21.3 ± 0.6 to 23 ± 0.6 mg g–1), were measured for the other five species. Changes in LMA with the relative irradiance were linked both to lamina thickness (LT) and to palisade/spongy parenchyma ratio (PP/SP). In the second case, the LMA changes may be related to an increase in lamina density as palisade parenchyma involves higher cell packing than spongy parenchyma. However, since PP/SP ratio showed a weak species-specific relationship with LMA, the increase in LT should be the main cause of LMA variation.  相似文献   

11.
12.
Jose A. Navarro-Cano   《Flora》2008,203(8):663-668
Cistus heterophyllus Desf. is an Iberian-north African endemic plant species with only one wild population left in Spain. A sowing experiment under controlled conditions was designed to assess both the seedling emergence rate and the growth fitness of C. heterophyllus on a litter layer of Brachypodium retusum (Pers.) Beau., which forms dense carpets around the remnant population of C. heterophyllus. In order to test the physical effects of B. retusum litter on Cistus seedling recruitment, six sowing treatments in pots were compared that combined three doses of litter (0, 0.6 and 1.1 kg m−2) and different physical locations of the seeds (above, below the litter layer or within a litter–peat mixture). B. retusum litter interfered with the seedling recruitment of C. heterophyllus, negatively affecting both seedling emergence and their early growth. Such an effect was more severe when the seeds were located above a 0.6 kg m−2 litter layer, although seedlings from seeds sown under the litter showed a growth reduction ranging from 58% to 100% compared to the no-litter treatment. A significant negative effect of the litter–peat mixture on the number of leaves, leaf size and number of branches of seedlings was also inferred. These data provide experimental evidence on the serious threat that B. retusum litter represents for the conservation and regeneration of the last population of C. heterophyllus in Spain.  相似文献   

13.
A 1.9 kb nucleotide sequence of part of the mitochondrial (mt) genome covering the cox1-trnT-rrnL-trnC-rrnS region, and the order of the remaining mitochondrial protein-coding genes for S. nasale of Sri Lankan origin, has been determined for analysis of the possible placement of this species in the genus Schistosoma. The gene order of this species is similar to that of the African and Indian Schistosoma species, but strikingly different from the East Asian species. Analysis of an alignment of the 1.9 kb sequence with available sequences from other schistosomes indicated affinities with S. spindale (found in Sri Lanka) and African species (in particular S. intercalatum and S. haematobium). Phylogenetic trees inferred from the alignment including 1 kb of RNA (transfer RNA and ribosomal RNA) sequence for 8 other Schistosoma spp. and Fasciola hepatica as an out-group revealed that S. nasale is placed proximally to S. spindale, S. intercalatum, S. haematobium and S. mansoni in the African sub-group while the East Asian species are more distant. S. incognitum lies basal to the combined African/Indian clade. The mtDNA analysis strongly supports the hypothesis that S. nasale is closely affiliated with the African/Indian schistosome group rather than the East Asian Schistosoma species.  相似文献   

14.
15.
Culicoides (Diptera: Ceratopogonidae) are vectors of pathogens that affect wildlife, livestock and, occasionally, humans. Culicoides imicola (Kieffer, 1913) is considered to be the main vector of the pathogens that cause bluetongue disease (BT) and African horse sickness (AHS) in southern Europe. The study of blood‐feeding patterns in Culicoides is an essential step towards understanding the epidemiology of these pathogens. Molecular tools that increase the accuracy and sensitivity of traditional methods have been developed to identify the hosts of potential insect vectors. However, to the present group's knowledge, molecular studies that identify the hosts of C. imicola in Europe are lacking. The present study genetically characterizes the barcoding region of C. imicola trapped on farms in southern Spain and identifies its vertebrate hosts in the area. The report also reviews available information on the blood‐feeding patterns of C. imicola worldwide. Culicoides imicola from Spain feed on blood of six mammals that include species known to be hosts of the BT and AHS viruses. This study provides evidence of the importance of livestock as sources of bloodmeals for C. imicola and the relevance of this species in the transmission of BT and AHS viruses in Europe.  相似文献   

16.
In this study we have assessed the capacity of five fungal and two bacterial species to biodegrade glass fiber acrylic composite filters which are utilized in air conditioners. The strains used were Trichoderma harzianum (2 strains), Trichoderma koningii, Penicillium spp., Aspergillus niger, Pseudomonas aeruginosa and Pseudomonas fluorescens. Pre-sterilized filters were incubated in solid or liquid media at 30 °C for 21 days. Biodegradability was monitored by evaluating microbial colonization, increase in biomass and weight loss of filters coupons. Among the species under investigation, the two strains of T. harzianum (MYA198 and BCC5828) showed the best biodegradability performance and were used to analyse total carbon and esterase activity. Our results clearly indicate that cells grown in the presence of shredded filters display a hydrolytic activity and lead to a consistent removal of the organic portion of the tested filters. This study suggests that a solid state fermentation process in suitable bioreactors based on T. harzianum species could be a suitable approach to acrylic composite filter biodegradation.  相似文献   

17.
The paper presents vegetation and climate reconstructions for Eemian and Early Weichselian in Central Europe based on detailed pollen data of the Klinge section. The sediments exposed in this profile were accumulated from the Saalian termination up to the Early Weichselian glaciation. A succession of forest communities, typical for the Eemian interglacial has been recorded. Pollen data indicate some oscillations during the very end of the Eemian (biozone E7). The climatic reconstructions show the heat supply rising gradually from the beginning of the interglacial to its middle part. A long-term cooling trend in January temperature was reconstructed for the second half of the interglacial. The difference between the optimum (zone E4b) and Pinus-Picea-Abies zone (E6) amounts to 4 °C, during the Pinus zone (E7) the temperature further decreased by 8 °C. The changes in July temperature were not so dramatic (about 3 °C).  相似文献   

18.
The synthesis and characterization of the binary complex of copper(II) with the antiepileptic drug valproic acid sodium salt (Valp) and the related ternary complex with 1,10-phenanthroline (phen) are reported, as well as the anticonvulsant properties of the latter. The characterization was carried out by means of elemental analyses, infrared (IR), UV–visible (UV–vis) spectrophotometry and Electron Paramagnetic Resonance (EPR). The X-ray crystal structure of the mononuclear complex bis(2-propylpentanoate)(1,10-phenanthroline)copper(II) [Cu(Valp)2phen] is showed for the first time. It crystallized in C2/c space group with unit cell dimensions of a = 14.939(1) Å, b = 19.280(1) Å, c = 9.726(1) Å, β = 97.27(2)°, V = 2778.8(4) Å 3 and Z = 8. The carboxylates bond in an asymmetric chelating mode and the copper atom adopts a highly distorted octahedral coordination, characterized by the sum of the angles of 365.9° around Cu(II) and its nearest atoms in the CuN2O2 + O2 chromophore instead of the expected 360° for a basal square planar geometry found in most Cu(II) complexes. Molecules assemble three by three through slipped π–π stacking of the aromatic phen with respectively 3.519 and 3.527 Å distances, in a head-to-tail arrangement. Studies of the anticonvulsant properties of this bioligand chelate evidenced its lack of efficacy in preventing MES-induced seizures. Interestingly, complex 4 protected mice against the Minimal Clonic seizures at doses that do not cause Rotorod toxicity, with an ED50 documenting very potent anticonvulsant activity in this model of seizure, a particularly useful pharmacological profile of activity for the treatment of Petit Mal seizures.  相似文献   

19.
The only two species of Choiromyces collected up to now in Spain, C. venosus and C. magnusii, were studied with both morphological and molecular methods. Phylogenetic inference of nrDNA ITS and LSU sequences showed that they should be considered independent species in the genus Choiromyces. Choiromyces venosus is a hypogeous fungus, infrequent but naturally present in the Iberian Peninsula, that is imported into Spain from central Europe without any indication of its origin or proper taxonomic identification. It is usually sold as highly-prized edible species of the genus Tuber such as T. magnatum. Choiromyces magnusii is a more frequent hypogeous fungus in Spain that is commercialized in spring on a local scale together with different species in the genus Terfezia. Additionally, the Australian species Reddellomyces westraliensis, which was introduced with Eucalyptus camaldulensis plantations, is cited here for the first time in Spain and Europe.  相似文献   

20.
The latest Cretaceous (Campanian–Maastrichtian) is characterized by several global cooling and intermittent warming events. These climatic changes influenced the palaeoceanography substantially, including changes of the deep water sources and surface water currents. One of the most prominent episodes of climatic cooling occurred during the Campanian–Maastrichtian transition. This study focuses on the palaeoclimate and palaeoceanography of the Campanian–Maastrichtian transition by analysing the calcareous nannofossils of DSDP Hole 390A (139.92–126.15 mbsf; Blake Nose). For the examination of calcareous nannofossils sixty samples were processed using the settling technique. Biostratigraphical index taxa (Broinsonia parca constricta, Uniplanarius trifidus, and Tranolithus orionatus) suggest a late Campanian age for the major part of the studied section. The calcareous nannofossils are well preserved, highly abundant (6.80 billion specimens/gram sediment) and diverse (80 species/sample). The assemblages are dominated by Prediscosphaera spp. (20.5%), Watznaueria spp. (20.3%) and Retecapsa spp. (9.8%). Cool water taxa (Ahmuellerella octoradiata, Gartnerago segmentatum, and Kamptnerius magnificus), however, appear less frequently and do not exceed more than 1%. Due to their rarity these cool water taxa do not support the existence of an intense cooling phase during the Campanian–Maastrichtian transition at DSDP Hole 390A. Around 133 mbsf several nannofossil taxa, however, show a distinctive turnover. Mesotrophic species like Discorhabdus ignotus, Zeugrhabdotus bicrescenticus and Zygodiscus exmouthiensis are abundant below 133 mbsf, whereas oligotrophic taxa like Watznaueria spp., Eiffellithus spp. and Staurolithites flavus become common above this level. These changes imply a decrease in the input of nutrients, perhaps caused by a reorganization of ocean currents (Palaeo Gulf Stream) and reduced upwelling.  相似文献   

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