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1.
A taxonomic clarification of Petrorhagia section Kohlrauschia (Caryophyllaceae). The morphology of the inflorescence bracts and seeds in Petrorhagia glumacea and the large-flowered form of P. 'prolifera' is reported together with observations on some artificially produced hybrids. Petorhagia glumacea and large-flowered p. 'prolifera' can be distinguished on the basis of bract and seed morphology. The taxonomic status of large-flowered P. 'prolifera' is recognized as P. obcordata. Two groups of intermediate, natural populations are described from the Peloponnese and it is suggested that they are of hybrid origin. The seeds of P. obcordata are polytypic and show a geographical distribution pattern. Seed morphology, which is the most useful diagnostic character for identification, is described in P. prolifera, P. velutina and the tetraploid P. nanteuilii.  相似文献   

2.
The dynamics of bacterioplankton and protozooplankton in twomaritime Antarctic lakes (Heywood Lake and Sombre Lake, SignyIsland, South Orkneys) were studied during the phase of icebreak-out (December and early January 1994/95). The lakes aresuffering animal-induced (fur seal) eutrophication, though HeywoodLake is most severely affected. Both lakes had morphologicallydiverse bacterial communities which increased during the studyperiod, reaching maxima of 80 x 108 l–1 in Heywood Lakeand 31.8 x 108 l–1 in Sombre Lake. Heterotrophic nanoflagellates(HNAN) reached a peak in late December with maxima of 40.6 x108 l–1 in Sombre Lake and 174 x 105 l–1 in HeywoodLake. Phototrophic nanoflagellates (PNAN) peaked in late Decemberafter ice loss in Heywood Lake (63 x 105 l–1), which coincidedwith a peak in a bloom of Chroomonas acuta which reached abundancesof 1.0 x 108 l–1. In Sombre Lake, ice persisted for alonger period and here PNAN reached their highest density atthe end of the study period (around 70.0 x 105 l–1). Ciliateabundance reached high levels in Heywood Lake (>60001–1),while in Sombre Lake maximum abundance was 568l–1. Protozooplanktondiversity was greater in the less-enriched Sombre Lake. Grazingrates of ciliates averaged 70.6 bacteria indiv.–1 h–1in Heywood Lake and 119.3 bacteria indiv.–1 h–1in Sombre Lake. The difference was a reflection of the differenttaxonomic make-up of the community in the lakes. HNAN grazingrates varied between 0.51 and 0.83 bacteria indiv.–1 h–1in Sombre and Heywood Lakes, respectively. Specific growth rates(r) h–1 in Sombre Lake were 0.028 for ciliates and 0.013for HNAN, and in Heywood Lake 0.010 for ciliates and HNAN 0.012.These growth rates result in doubling times ranging between38 and 69 h for ciliates and around 55 h for HNAN.HNAN grazingon bacteria was curtailed in Heywood Lake in early January asa result of predation by microcrustacean larvae feeding on theplankton. Thus, for a short phase top-down control was apparentin the dynamics of Heywood Lake, a feature uncommon in Antarcticlake ecosystems. The impact of natural eutrophication on thesesystems is discussed in relation to other unaffected Antarcticlakes.  相似文献   

3.
The copepod Pseudoboeckella poppei (Daday) (Calanoida, Centropagidae) was sampled from Sombre and Heywood Lakes on Signy Island, Antarctica (60° S, 45° W) between January 1984 and March 1985. Sombre Lake is clear and oligotrophic with little phytoplankton and a bottom sediment low in organic content. By contrast Heywood Lake is turbid and mesotrophic; a substantial phytoplankton develops in summer and the bottom sediments are comparatively rich in organics. Both lakes freeze over for much of the year, forcing the copepods to adopt a benthic feeding strategy over winter. Adult Pseudoboeckella feed on phytoplankton when this is available, but also on detritus, diatoms and short algal filaments stirred up from the sediment. In Heywood Lake, male copepods show a smooth seasonal trend in lipid content with lipid being synthesised in early summer and utilised in late summer and winter. The summer increase in lipid content is associated with an increase in dry weight. Female lipid contents show evidence of two peaks of egg production. In Sombre Lake both male and female copepods increase in size during summer and show a wider range of lipid contents than in Heywood Lake; it is likely that this is due to the poorer winter feeding conditions which necessitate the synthesis of a much larger store of reserves during the summer. In contrast to marine calanoid copepods, lipid stores are exclusively triacylglycerol with no trace of wax ester.  相似文献   

4.
The allelopathic effects of neo-clerodane diterpenes, isolated from Teucrium chamaedrys (L.), have been evaluated on the seed germination and seedling growth of four coexisting Mediterranean species (Dactylis hispanica, Petrorhagia velutina, Phleum subulatum and Petrorhagia saxifraga) and two cosmopolitan weeds (Amaranthus retroflexus and Avena fatua). All of the structures have been elucidated on the basis of their spectroscopic features. The bioassays data, analyzed by principal component analysis, showed more negative effects on weeds respect to coexisting species. Moreover D. hispanica, P. velutina, P. subulatum showed both stimulating or inhibiting effects depending on the type of metabolite and the concentration used in the test.  相似文献   

5.
Three new species are described in Biscutella sect. Biscutella from the central-eastern mountains of the Iberian Peninsula: B. bilbilitana Mateo & M.B. Crespo, B. segurae Mateo & M.B. Crespo, and B. conquensis Mateo & M.B. Crespo. They are characterized morphologically, ecologically and chorologically. Data separating them from B. valentina (L.) Heywood, a taxon to which they sometimes have been referred, are also reported.  相似文献   

6.
Pearsonema (syn. Capillaria) plica is a nematode that resides in the urinary bladder of canids, felids and mustelids (definitive hosts) and is classified in the same class as Trichuris spp. Epidemiological and clinical data on Pearsonema plica infection in domestic animals are limited. The nematode has an indirect lifecycle that involves earthworms as intermediate hosts. A six-year-old crossbred dog from Greece, presented a history of intermittent pollakiuria and hematuria. At urine analysis, P. plica eggs were found in the urine sediment. The dog was successfully treated with a double dose of milbemycin. To the best of our knowledge this is the first case of urinary capillariasis diagnosed in a domestic animal in Greece.  相似文献   

7.
Geranium kikianum Kit Tan & G. Vold sp. nov. (Geraniaceae) is illustrated and described as a new species endemic to Greece. It occurs beside streams and other wet places in open Pinus nigra forest at the foothills of Mt Taigetos in the southern Peloponnese. It is closely related to G. macrorrhizum, a species more widely distributed in southern and central Europe, ranging from the southern Alps to the Balkan Peninsula. It differs from the latter by its smaller and narrower deflexed petal limb, slender claw and occurrence in wet habitats. The genome sizes of G. kikianum and of Greek populations of G. macrorrhizum are presented here for the first time. The nuclear DNA content (2C values) of 2.84 pg for G. kikianum and 2.83 and 2.87 pg for two G. macrorrhizum populations from Greece probably corresponds to a 2n=92 cytotype while the smaller genome size of 1.45 pg in a population of G. macrorrhizum from Mt Smolikas, Greece may correspond to a 2n=46 cytotype.  相似文献   

8.
The potential allelopathic effects of 14 stilbenoids and five flavonoids, isolated from leaves of Carex distachya Desf., were evaluated on the seed germination and seedling growth of three coexisting Mediterranean species (Dactylis hispanica, Petrorhagia velutina, and Phleum subulatum). The structures of the metabolites have been elucidated on the basis of their spectroscopic features (1D and 2D NMR experiments and EI–MS and ESI–MS data). The bioassays showed species-specific effects of the metabolites from C. distachya, specially on the plant growth (root and shoot elongation) which resulted significantly stimulated or inhibited at 10−4 M concentration. The effects on root elongation is generally greater than the shoot growth at all the tested concentrations (10−4–10−8 M). Cluster of biological data showed interesting relationships between the chemical structures of the compounds and their biological effects.  相似文献   

9.
Pollen morphology of 10 taxa from Turkey, four of them endemic, belonging to the genus Petrorhagia (Caryophyllaceae), P. alpina subsp. alpina, P. alpina subsp. olympica, P. cretica, P. dubia, P. hispidula, P. lycica, P. pamphylica, P. peroninii, P. prolifera and P. saxifraga, has been investigated using light (LM) and scanning electron (SEM) microscopy. Pollen morphology differences among these taxa have been determined. The pollen type of investigated taxa is polyporate (12–22-porate), sphaeroidal, the exine exhibits a tectate structure and a microechinate ornamentation. Petrorhagia alpina subsp. alpina has the smallest pollen grain diameter (18.57 μm) and P. dubia the largest one (37.80 μm). The number of pores ranges from 12 (in P. dubia and P. saxifraga) to 22 (in P. alpina subsp. alpina and P. alpina subsp. olympica and P. hispidula) with a minimum pore diameter of 2.37 μm in P. alpina subsp. alpina and a maximum pore diameter of 4.23 μm in P. peroninii. The exine thickness ranges from 1.73 μm in P. saxifraga to 3.78 μm in P. pamphylica. In this study, the systematic implications are discussed in the light of palynological results.  相似文献   

10.
The study of the primitive gerbil remains of Pseudomeriones, recovered from the micromammalian sites of Paliambela-B and Monasteri (Latest Miocene, Northern Greece), gives evidence for a new species, which is characterized by its large size and simple molar morphology. A cladistic analysis based on dental characters affiliates this form with P. rhodius and P. pythagorasi and enables an intrageneric phylogenetic scenario.  相似文献   

11.
The distribution and activity of communities of sulfate-reducing bacteria (SRB) and methanogenic archaea in two contrasting Antarctic sediments were investigated. Methanogenesis dominated in freshwater Lake Heywood, while sulfate reduction dominated in marine Shallow Bay. Slurry experiments indicated that 90% of the methanogenesis in Lake Heywood was acetoclastic. This finding was supported by the limited diversity of clones detected in a Lake Heywood archaeal clone library, in which most clones were closely related to the obligate acetate-utilizing Methanosaeta concilii. The Shallow Bay archaeal clone library contained clones related to the C(1)-utilizing Methanolobus and Methanococcoides and the H(2)-utilizing Methanogenium: Oligonucleotide probing of RNA extracted directly from sediment indicated that archaea represented 34% of the total prokaryotic signal in Lake Heywood and that Methanosaeta was a major component (13.2%) of this signal. Archaea represented only 0.2% of the total prokaryotic signal in RNA extracted from Shallow Bay sediments. In the Shallow Bay bacterial clone library, 10.3% of the clones were SRB-like, related to Desulfotalea/Desulforhopalus, Desulfofaba, Desulfosarcina, and Desulfobacter as well as to the sulfur and metal oxidizers comprising the Desulfuromonas cluster. Oligonucleotide probes for specific SRB clusters indicated that SRB represented 14.7% of the total prokaryotic signal, with Desulfotalea/Desulforhopalus being the dominant SRB group (10.7% of the total prokaryotic signal) in the Shallow Bay sediments; these results support previous results obtained for Arctic sediments. Methanosaeta and Desulfotalea/Desulforhopalus appear to be important in Lake Heywood and Shallow Bay, respectively, and may be globally important in permanently low-temperature sediments.  相似文献   

12.
The mammal locality of Antonios is one of the few known early-middle Miocene ones of Greece with large mammals. It is situated in Chalkidiki Peninsula (Macedonia, Greece) and includes both small and large mammals. The study of the carnivores found in Antonios indicates the presence of the following taxa: Proputorius cf. P. sansaniensis, Protictitherium gaillardi, Protictitherium cf. P. crassum, Percrocuta sp., Percrocutidae indet. and Pseusaelurus romieviensis. The material of each taxon is described, compared with other material from various Eurasian localities and determined. The species P. cf. sansaniensis and Promieviensis are traced for first time in Eastern Mediterranean, while Percrocuta for first time in Greece. The presence of the other carnivoran taxa in the Antonios fauna is also interesting as they are recognized in older stratigraphic levels enriching our knowledge about their stratigraphic distribution. The carnivores of Antonios cannot offer significant data for the dating of the fauna but its age is discussed using the data coming from the carnivores as well as those from older studies of the micromammals and suoids.  相似文献   

13.
Serpentine (ophiolithic) substrate covers large areas in the Balkans, more so than in any other part of Europe. These areas extend from north to south mainly in the mountainous central regions and represent specialized habitats for basiphilous-calcifugal plants. Biodiversity in the area is high, with a great number of interesting local and regional endemics. The high number of endemics indicates the importance of serpentine habitats as centres for floristic differentiation and speciation. The number of Balkan endemics growing on serpentine is c. 335 taxa (species and subspecies) of which 123 are obligate. Their distribution is presented in 50 × 50 km UTM squares as adopted in the Atlas Florae Europaeae project coordinated at Helsinki. The richest (in number of taxa) squares are situated in NW Greece (Epirus), the island of Evvia, N Albania together with SW Serbia, and N Greece (Vourinos). They indicate important centres of plant diversity in the Balkans, areas to be noted for conservation strategy. Features responsible for the distribution and abundance of these obligate serpentine endemics include: 1) edaphic isolation in relation to type of bedrock (lime, dolomite, marble, schist, etc.), 2) mountain island isolation (Smolikas, Vourinos, Ostrovica, etc.), 3) island isolation (Evvia) and 4) continuous long-term isolation without interruption or disturbance of speciation.  相似文献   

14.
The weight–length relationships (WLRs) for six endemic fish species of Greece are presented here. All WLRs were highly significant (P < 0.001), and reported for the first time for five of the six species. Moreover, for three of the species studied, new maximum body lengths are provided.  相似文献   

15.
Harpalus apache sp. n. is described from the eastern part of New Mexico, USA (type locality: Hwy I 40, near Santa Rosa, Guadalupe Co). The new species is very similar in appearance to H. cordatus (Le-Conte, 1853) but readily distinguished from it by the male genitalia structure. These two species constitute a natural taxon which is included as the “cordatus” group (= Opadius Casey, 1914) in the subgenus Glanodes Casey, 1914. Distinctive characters, distribution and composition of the subgenus Glanodes and two its species groups (“obliquus” and “cordatus”) are provided. Two names, H. cordatus (LeConte, 1853) (= H. tadorcus Ball, 1972) and H. puncticeps (Casey, 1914) (= H. cunctipeps Ball, 1973), rejected because of the secondary homonymy, are reinstated as valid since they are not homonyms of Ophonus cordatus (Duftschmid, 1812) and Ophonus puncticeps Stephens, 1828, respectively.  相似文献   

16.
Quercus coccifera (kermes oak) is the most common species of the Mediterranean maquis with a wide distribution across the Mediterranean Basin. This paper presents a syntaxonomic overview of the Q. coccifera plant communities in the Mediterranean zone of Greece (Quercetea ilicis) based on the classification of 221 relevés from 34 (17 continental and 17 insular) mountainous areas throughout Greece. Two associations and eight sub-associations are described and presented in a synoptic constancy table. Querco cocciferae–Pistacietum lentisci is the most widespread, is found in the entire continental Greece and most islands, and is further subdivided into five sub-associations reflecting primarily local peculiarities in the disturbance regime and the influence of local floristic elements. Rhamno lycioidis–Cocciferetum (Rivas Goday & Rivas-Martínez 1954), on the other hand, is geographically confined on the island of Crete and is further subdivided into three sub-associations, reflecting differences in the annual precipitation, and they are characterized by the presence of many phryganic and grazing-resistant species. Climate and the anthropogenic pressure have been identified to be the most important factors determining the structure and the floristic composition of Q. coccifera Mediterranean shrublands of Greece.  相似文献   

17.
Heterophyes heterophyes is reported for the first time from the snail host Pirenella conica in Greece. H. aequalis and H. dispar are reported for the first time from Greece and from Europe. The results presented, together with the available data on necropsies of dogs and cats, human infections and the biotope preference of the snail, suggest that Greece is an important focus of infection in Europe.  相似文献   

18.
In a eutrophic peat bog impregnated with mineral springs in the Carpathians, where the glacial relics Swertia perennis and Pedicularis sceptrum-carolinum have earlier been shown to occupy different microhabitats, an analysis of the relationships of these species with accompanying species has been made on the basis of numerous quadrats and a correlation method. The closest floristic associates of the two species are quite different, and the results of this analysis are broadly in agreement with subjective assignments made earlier by phytosociologists.Nomenclature follows T. G. Tutin & V. H. Heywood (eds.), Flora Europaea, Vols. I–V. Cambridge Univ. Press, Cambridge, 1964, 1968, 1972, 1976, 1980 for Cormophyta and R. van der Wijk (ed.), Index Muscorum, Vols. I, II. Utrecht, 1959, 1962 for Bryophyta.  相似文献   

19.
The distribution and activity of communities of sulfate-reducing bacteria (SRB) and methanogenic archaea in two contrasting Antarctic sediments were investigated. Methanogenesis dominated in freshwater Lake Heywood, while sulfate reduction dominated in marine Shallow Bay. Slurry experiments indicated that 90% of the methanogenesis in Lake Heywood was acetoclastic. This finding was supported by the limited diversity of clones detected in a Lake Heywood archaeal clone library, in which most clones were closely related to the obligate acetate-utilizing Methanosaeta concilii. The Shallow Bay archaeal clone library contained clones related to the C1-utilizing Methanolobus and Methanococcoides and the H2-utilizing Methanogenium. Oligonucleotide probing of RNA extracted directly from sediment indicated that archaea represented 34% of the total prokaryotic signal in Lake Heywood and that Methanosaeta was a major component (13.2%) of this signal. Archaea represented only 0.2% of the total prokaryotic signal in RNA extracted from Shallow Bay sediments. In the Shallow Bay bacterial clone library, 10.3% of the clones were SRB-like, related to Desulfotalea/Desulforhopalus, Desulfofaba, Desulfosarcina, and Desulfobacter as well as to the sulfur and metal oxidizers comprising the Desulfuromonas cluster. Oligonucleotide probes for specific SRB clusters indicated that SRB represented 14.7% of the total prokaryotic signal, with Desulfotalea/Desulforhopalus being the dominant SRB group (10.7% of the total prokaryotic signal) in the Shallow Bay sediments; these results support previous results obtained for Arctic sediments. Methanosaeta and Desulfotalea/Desulforhopalus appear to be important in Lake Heywood and Shallow Bay, respectively, and may be globally important in permanently low-temperature sediments.  相似文献   

20.
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