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1.
The MHV-68 (designed as Murid herpesvirus 4 (MuHV 4) strain 68) isolated from two rodents, Myodes glareolus and Apodemus flavicollis, is considered as a natural pathogen of free-living murid rodents. Recently, the detection of MHV antibodies in the blood of animals living in the same biotope as MHV-infected mice has suggested that ticks may have a role in the transmission of this pathogen. Ixodes ricinus is one the most abundant tick species in Europe known to transmit multiple pathogens causing human and animal diseases. In this study, nymphs and larvae feeding on 116 individuals of a temperate lizard species—the green lizard Lacerta viridis captured in the Slovak Karst National Park, were examined for MHV-68. The specific sequence of virion glycoprotein 150 was amplified in DNA individually isolated from I. ricinus ticks using single-copy sensitive nested polymerase chain reaction. MHV-68 was detected in ten of 649 nymphs and in five of 150 larvae, respectively. We found that 9.6% of green lizards fed at least one MHV-68-infected immature tick. Occurrence of MHV-68 within all ticks tested was 1.8%. This study is first to show that immature I. ricinus ticks feeding on free-living lizards in a Central European region could be infected with gammaherpesvirus (MHV-68), naturally infecting free-living murid rodents. Our results provide evidence supporting the hypothesis that ticks may play a mediating role in circulation of MHV-68 in nature.  相似文献   

2.
For the first time unequivocal fossil remains of a green toad (Bufo viridis s.l.) are described in the Iberian Peninsula. The fossils come from the Cueva Victoria site, a late Early Pleistocene (ca. 1.1–1.2 Ma) karstic filling in semi-arid southeastern Spain (Murcia region). By extension, other remains from two other Early Pleistocene Spanish localities, Barranco León D (ca. 1.3 Ma) and Almenara-Casablanca 3 (ca. 1.1 Ma), are cautiously attributed to the group B. viridis. The B. viridis group was previously reported with some uncertainty to the west of its current distribution area in Western Europe (Spain and France) in the Pliocene (Bufo cf. viridis) and less probably in the Early Miocene (Bufo aff. viridis). Since no osteological differences have been established between the recently described extant species of B. viridis s.l. (e.g. Bufo balearicus, Bufo siculus, Bufo boulengeri, B. viridis sensu stricto and Bufo variabilis) no precise palaeobiogeographical relationships can be drawn for the Spanish fossils. However, the occurrence of a third species of bufonid toad during the Pleistocene in the South of the Iberian Peninsula raises some interesting ecological questions in relation to the local disappearance of the green toad, which can be hypothetically linked to the intensification of the Pleistocene glacial/interglacial climate dynamic or to probable competition with another toad, Bufo calamita.  相似文献   

3.

Lateralization is one of the specific characteristics of animals, occurring in both invertebrates and vertebrates. Lateralization exists at two levels, individual level and population level. This research is focused on the individual- and population-level lateralization of the European green lizard (Lacerta viridis) under laboratory conditions. Lateralization was observed experimentally in a modified T-maze without the possibility of visual control by lizards. Lizards were stimulated by a piston from the caudal side to simulate a predator attack from behind. The numbers of left and right choices were evaluated. Statistical analysis confirmed no statistically significant difference in lateralization at both the individual and population levels. The absence or presence of autotomy suggests that non-biased lizards have a better chance of escape from a predator than left- or right-biased individuals. In the population of L. viridis studied by us, it seems that to be non-biased could be the best strategy to survive predator attacks.

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4.
Summary Thermophilic Actinomycetes were isolated from various peat samples and examined in detail. Most of them were classified as Thermoactinomyces vulgaris, a species which frequently occurs in very different habitats.The characters which separate Thermoactinomyces thalpophilus from Thermoactinomyces vulgaris are discussed. They are unstable and not sufficiently characteristic so that the taxonomic position of Thermoact. thalpophilus now becomes doubtful. Thermomonospora viridis comb. nov. which is distinguished by a graygreen aerial mycelium and the formation of a green pigment has been particularly studied and described. Thermoactinomyces monosporus Schütze and Thermoactinomyces viridis Schuurmans are synonyma. Streptomyces strins isolated and grown at 45° C should be called thermotolerant rather than thermophilic. They differ from known nesophilic species in their temperature requirements only.  相似文献   

5.
6.
Andrej ?erňansky 《Biologia》2011,66(5):899-911
This paper deals with the squamate fauna from three Neogene localities in Slovakia. Neogene lizards and snakes have rarely been reported from this region and many aspects of their evolution and palaeodiversity are still poorly understood. Squamate remains from the Upper Miocene (MN 9) locality of Borsky Sv?ty Jur belong to at least five different taxa: Lacerta sp., Pseudopus sp., Colubroidea indet. (? Elapidae), Natricinae indet. and Colubridae indet. The ophidian assemblage from Ivanovce (Lower Pliocene; MN 15b) is dominated by colubrids, mainly Zamenis longissimus. The remainder is comprised of the species Natrix natrix. Squamate material from this locality also includes Lacerta cf. agilis, Pseudopus sp. and Ophisaurus sp., while that from Hajnáčka (Upper Pliocene; MN 16a) is extremely poor, comprising just one taxon - Natrix natrix. The Ivanovce material represents the oldest proof of the former existence of the species Zamenis longissimus and Natrix natrix in the Slovak Republic. The composition of this snake fauna indicates faunistic and palaeoecological changes at the end of the Miocene, although this was not as rapid as at similar localities in Europe. The squamate fauna of Slovakia has changed very little since the beginning of the Pliocene, and the majority of taxa are represented by species that currently occur in this region.  相似文献   

7.
A method for enzymatic isolation of protoplasts from the unicellular green alga Eremosphaera viridis for patch-clamp measurements is described. Viable protoplasts with “patch-clean” plasma membranes could only be isolated when combining high enzyme concentrations and long incubation times. In whole-cell recordings the protoplasts exhibited electrical properties similar to those measured in intact cells. Taken together with the protoplasts' ability for rapid deplasmolysis after transfer into hypotonic solution, this indicates the viability of the isolated protoplasts.  相似文献   

8.
A large number of plant macrofossils from several Middle to Upper Miocene localities from Iceland have been studied. The fossil material includes four ferns and fern allies, seven conifers, and about 40 species of flowering plants. Betula islandica and Salix gruberi are described as new species. Coniferous twigs previously ascribed to the genus Sequoia are shown to belong to Cryptomeria based on macro‐morphological and epidermal features. Fossil plants from Iceland are compared with coeval fossil taxa from Europe and North America and with living plants. The main finding is that the Miocene flora of Iceland belongs to a widespread Neogene northern hemispheric floral type including plants whose representatives are restricted to East Asia, North America and to western Eurasia at the present time. Previously inferred conspicuous similarities to North American modern equivalents appear to be misleading. The type of vegetation in four plant‐bearing sedimentary formations from the late Mid Miocene to Late Miocene, the 12 Ma Brjánslækur‐Seljá Formation, the 10 Ma Tröllatunga‐Gautshamar Formation, the 9–8 Ma Skarðsströnd‐Mókollsdalur Formation, and the 7–6 Ma Hreðavatn‐Stafholt Formation, corresponds to a humid temperate broadleaved (deciduous)–coniferous mixed forest dominated by Betulaceae, Fagaceae and Acer. Changes in species composition in the sedimentary formations reflect a shift from warm temperate (Cfa climate) to cool temperate (Cfb climate) conditions from the late Mid Miocene to the latest Miocene. This shift was connected to repeated phases of extinction and colonization. Specifically, one set of thermophilic taxa including Magnolia, Liriodendron, Sassafras and Comptonia went extinct between 12 and 10 Ma, and appears to have been replaced by another set of thermophilic taxa in the 10 Ma formation (Juglandaceae aff. Pterocarya/Cyclocarya, Rhododendron ponticum type). The 9–8 and 7–6 Ma formations are characterized by taxa that migrated to Iceland from Europe, such as Fagus gussonii, Betula cristata and Pterocarya fraxinifolia type. Although there is convincing evidence that plants colonized Iceland both from North America and Europe until 12 Ma, migration in the younger formations (9–8, 7–6 Ma) is suggested to have occurred mainly from Europe. © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society, 2005, 149 , 369–417.  相似文献   

9.
10.
Two catarrhine mandibles and five isolated teeth have been discovered from Early Miocene localities in Western Kenya. One mandible comes from the well‐known locality of Songhor whereas the other is from a newly discovered locality, Lower Kapurtay, located near Songhor. The mandibles both can clearly be assigned to the species Rangwapithecus gordoni based on molar morphology, which is unique among Early Miocene catarrhines. The isolated specimens can be assigned to Rangwapithecus based on their similarities in morphology to the homologues preserved in the two mandibles. These specimens provide important new information about the dentognathic morphology of Rangwapithecus, which is described in detail. The mandible from Songhor (KNM‐SO 22228) represents the first definitive female mandible of Rangwapithecus. The Lower Kapurtay mandible (KNM‐KT 31234) appears to be male but is much smaller than another recently described male mandible of this species (KNM‐SO 17500) and the type maxilla (KNM‐SO 700). These specimens enable a reassessment of the attributions of all other mandibles and isolated lower teeth of Rangwapithecus, and we present a complete hypodigm of the mandibular and lower dental material for the species. Finally, we provide some additions to the diagnosis of Rangwapithecus gordoni based on previously unknown morphology. Am J Phys Anthropol 153:341–352, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   

11.
12.
Under nitrogen deficiency the unicellular chlorococcalean green alga, Eremosphaera viridis De Bary, was able to synthesize secondary carotenoids (SC). Nine SC were identified as six astaxanthin esters, echinenone, canthaxanthin and a lutein ester, previously not described in green algae under nitrogen deficiency. These SC, jS-carotene and the main part of lutein were located in lipid bodies outside the chloroplasts in the cytosol. The synthesis of SC could be inhibited by the herbicides norflurazon and nicotine. This result supported the idea that SC in cells ot Eremosphaera viridis were synthesized de novo rather than derived from primary carotenoids.  相似文献   

13.
Microhabitat selection and seasonal activity of the snake-eyed skink, Ablephaus kitaibelii fitzingeri, are compared to the two lacertid lizards (Lacerta viridis and Podarcis muralis) that co-occur in many of its habitats. The food composition of A. k. fitzingeri is also described. Significant differences in microhabitat selection and seasonal activity among the three species were found. The snake-eyed skink was associated with open grasslands, and with a low level of scrub, bare soil and rock cover. The microhabitat preference of L. viridis was quite similar to that of the skink, but with a higher preference for scrub. P. muralis occurred in places with greater rock and bare soil cover, and more scrub than A. k. fitzingeri. Activity of the snake-eyed skink decreased dramatically in summer, probably because of the reduced thermal inertia originating from the extremely small size of this species, but its seasonal activity overlapped with those of the lacertids. Stomach content analysis of the snake-eyed skink suggests that it is a generalist predator of small, mainly flightless arthropod prey. Competition with juvenile lacertids and predation by adult L. viridis are conceivable for the snake-eyed skink.  相似文献   

14.
In this study, carotenoid and glycerol production in two unicellular green algae (Dunaliella salina and D. viridis) isolated from the Gave-Khooni salt marsh grown in media containing five different salt concentrations (0.17, 1, 2, 3, and 4 M NaCl) were evaluated under sterile conditions. Algae growth decreased as the medium salinity increased. Optimum growth of D. salina and D. viridis were obtained at 2 and 1 M NaCl, respectively. As salinity increased, glycerol and carotenoid production were increased in D. salina, whereas lower values for these products were produced in D. viridis under the same conditions. Furthermore, the cell color of D. salina changed from green to orange-red following accumulation of carotenoid, but the color of D. viridis was not changed. Thereby, it seems that the Iranian D. salina may be suitable for carotenoid production (betacarotene) on a large scale. In addition, since carotenoid compounds enhance the efficiency of photosynthesis and glycerol synthesis, it appears that the pathway for glycerol production and mechanisms of salt tolerance in D. viridis are unique from those of D. salina.  相似文献   

15.
Abstract

We here describe new remains of amphibians and reptiles from the early Miocene (MN 4) of two different Greek localities, Aliveri and Karydia. The newly described material consists of urodelans, alytids, indeterminate anurans, turtles, crocodylians, lacertids, indeterminate scincomorphs, anguids, colubrids, viperids, and indeterminate snakes. The presence of the frog Latonia cf. gigantea in Greece is documented for the first time. Additionally, the presence of viperids in Aliveri implies a much wider distribution for these snakes during the early Miocene of Europe. Of special interest is the presence of a peculiar colubrid that seems to possess a hitherto unknown vertebral structure, which is herein defined as the ‘paracentral ridge’. Although incomplete, the new material has important taxonomic and biogeographic implications, as it enhances our understanding of southeastern European herpetofaunas from the early Miocene, a time period that was characterised by major dispersal and extinction events and climatic change that affected the whole continent.  相似文献   

16.
Aim In this paper we investigate the evolutionary history of the Eurasian green woodpecker (Picus viridis) using molecular markers. We specifically focus on the respective roles of Pleistocene climatic oscillations and geographical barriers in shaping the current population genetics within this species. In addition, we discuss the validity of current species and subspecies limits. Location Western Palaearctic: Europe to western Russia, and Africa north of the Sahara. Methods We sequenced two mitochondrial genes and five nuclear introns for 17 Eurasian green woodpeckers. Multilocus phylogenetic analyses were conducted using maximum likelihood and Bayesian algorithms. In addition, we sequenced a fragment of the cytochrome b gene (cyt b, 427 bp) and of the Z‐linked BRM intron 15 for 113 and 85 individuals, respectively. The latter data set was analysed using population genetic methods. Results Our phylogenetic results support the monophyly of Picus viridis and suggest that this taxon comprises three allopatric/parapatric lineages distributed in North Africa, the Iberian Peninsula and Europe, respectively. The North African lineage split from the Iberian/European clade during the early Pleistocene (1.6–2.2 Ma). The divergence event between the Iberian and the European lineages occurred during the mid‐Pleistocene (0.7–1.2 Ma). Our results also support a post‐glacial range expansion of these two lineages from distinct refugia located in the Iberian Peninsula and possibly in eastern Europe or Anatolia, which led to the establishment of a secondary contact zone in southern France. Main conclusions Our results emphasize the crucial role of both Pleistocene climatic oscillations and geographical barriers (Strait of Gibraltar, Pyrenees chain) in shaping the current genetic structure of the Eurasian green woodpecker. Our molecular data, in combination with diagnosable plumage characters, suggest that the North African green woodpecker (Levaillant’s woodpecker) merits species rank as Picus vaillantii (Malherbe, 1847). The two European lineages could be distinguished by molecular and phenotypic characters over most of their respective geographical ranges, but they locally exchange genes in southern France. Consequently, we prefer to treat them as subspecies (P. viridis viridis, P. viridis sharpei) pending further studies.  相似文献   

17.
《Journal of bryology》2013,35(3):209-214
Abstract

The two species of Buxbaumia Hedw. known to occur in Europe were both originally discovered on this continent and were the earliest in the genus (as presently delimited) to be described. Already widely known, Buxbaumia aphylla Hedw., was validated by Johannes Hedwig in 1801, whereas B. viridis (DC.) Moug. & Nestl. was initially described as a variety of B. aphylla by Augustin Pyramus de Candolle in 1815. After two centuries in the bryological literature, these taxa are herein effectively typified. Lectotypes for the names B. aphylla and B. viridis are designated based on original herbarium sheets from the Hedwig-Schwägrichen and De Candolle collections in G.  相似文献   

18.
Ten populations of the green toad, Bufo viridis, from three areas having different climatic regimes were compared. Multivariate analyses of morphological characteristics revealed three distinct populations of green toads: the first group inhabiting the lowland and humid localities was characterized by a small body size, the second group occurred at higher altitudes and in desert areas had a significantly larger body size, while the third group from the Mediterranean localities was characterized by a large tympanum, a longer tarsus and short first toes. Interestingly, the specimens from Giresun Island were clustered with the second group with a similar pattern of body size. Differences in the morphological characteristics among populations were positively associated with ecological conditions, and not with geographic distance. Some characteristics previously used for taxonomic purposes in B. viridis were shown to be associated with local climatic conditions.  相似文献   

19.
R. Zetter  M. Hesse 《Grana》2013,52(5):285-294
The morphology of pollen tetrads and viscin threads is described in fossil Ericaceae pollen from various Eocene/Oligocene/Miocene localities in Europe (Germany, Austria), North America (eastern U.S.A.), and Asia (eastern China). The typical characters of the tetrad configuration, the exine ornamentation and sculpturing, and especially the viscin thread morphology are extremely similar to or even indistinguishable from that in extant members of Rhododendron. All these pollen morphological features strongly suggest that all the investigated material can be assigned to a modern taxon of the Ericaceae: either to Rhododendroideae or even to Rhododendron itself.  相似文献   

20.

Background

In spite that chemoreception is important in sexual selection for many animals, such as reptiles, the mechanisms that confer reliability to chemical signals are relatively unknown. European green lizards (Lacerta viridis) have substantial amounts of α-tocopherol ( = vitamin E) in their femoral secretions. Because vitamin E is metabolically important and can only be attained from the diet, its secretion is assumed to be costly. However, its role in intraspecific communication is unknown.

Methodology/Principal Findings

Here, we experimentally show that male European green lizards that received a dietary supplement of vitamin E increased proportions of vitamin E in their femoral secretions. Furthermore, our experiments revealed that females preferred to use areas scent marked by males with experimentally increased vitamin E levels in their secretions. Finally, female preferences were stronger when vitamin E differences between a pair of males'' secretions were larger.

Conclusions/Significance

Our results demonstrate that female green lizards are able to discriminate between males based on the vitamin E content of the males'' femoral secretions. We suggest that the possible cost of allocating vitamin E to secretions, which might be dependent on male quality, may be a mechanism that confers reliability to scent marks of green lizards and allows their evolution as sexual signals.  相似文献   

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