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1.
Population characteristics of two seahorse species, Hippocampus coronatus and Hippocampus mohnikei, in seagrass beds in the southern coastal waters of Korea were determined based on field observations. In Zostera beds in the Yeosu area, there was a mean density of 2.9 seahorses per 1,000?m2 for H. coronatus and 1.4 seahorses per 1,000?m2 for H. mohnikei. The greatest numbers of young individuals of both species were observed in July, with numbers decreasing through November. The male:female sex ratio was 1:1.6 for H. mohnikei and 1:1.7 for H. coronatus. Breeding males of H. coronatus and H. mohnikei were observed from July to November and from July to September, respectively. Within the study site, the populations of the two seahorse species exhibited low density and patchy distributions, with variation in temporal abundance being significantly correlated with water temperature. The findings of this study provide the basis for future research on the population status of H. coronatus and H. mohnikei in seagrass beds. 相似文献
2.
Arbuscular mycorrhizal fungi (AMF) live in symbiosis with most plant species and produce underground extraradical hyphal networks functional in the uptake and translocation of mineral nutrients from the soil to host plants. This work investigated whether fungal genotype can affect patterns of interconnections and structural traits of extraradical mycelium (ERM), by comparing three Glomeraceae species growing in symbiosis with five plant hosts. An isolate of Funneliformis coronatus consistently showed low ability to form interconnected ERM and self-incompatibility that represented up to 21 % of hyphal contacts. The frequency of post-fusion self-incompatible interactions, never detected before in AMF extraradical networks, was 8.9 %. In F. coronatus ERM, the percentage of hyphal contacts leading to perfect hyphal fusions was 1.2–7.7, while it ranged from 25.8–48 to 35.6–53.6 in Rhizophagus intraradices and Funneliformis mosseae, respectively. Low interconnectedness of F. coronatus ERM resulted also from a very high number of non-interacting contacts (83.2 %). Such findings show that AMF genotypes in Glomeraceae can differ significantly in anastomosis behaviour and that ERM interconnectedness is modulated by the fungal symbiont, as F. coronatus consistently formed poorly interconnected networks when growing in symbiosis with five different host plants and in the asymbiotic stage. Structural traits, such as extent, density and hyphal self-compatibility/incompatibility, may represent key factors for the differential performance of AMF, by affecting fungal absorbing surface and foraging ability and thus nutrient flow from soil to host roots. 相似文献
3.
Andrew L. Lissner 《Journal of experimental marine biology and ecology》1980,48(2):185-193
Effects of turbulence on activity of the sea urchin Centrostephanus coronatus Verrill were studied using a new method referred to as the trip-thread method which recorded incidences of emergence from burrows during activity periods. During calm conditions, the number of C. coronatus emerging at 5 m depth was not significantly different from the number emerging at 15 m depth, representing 97% and 92% activity in the populations, respectively; however, during turbulent conditions, the number of individuals emerging at 5 m was significantly less than the number emerging at 15 m, representing 48% and 92% activity, respectively. These results suggest an inverse relationship between turbulence and activity. Although behavioral adaptations, such as reduced activity, allow urchins to occupy turbulent areas, extreme conditions may exclude them entirely. Differences in activity may affect grazing by sea urchins which can significantly affect the species composition and abundance of benthic communities. 相似文献
4.
Résumé La composition en sucres des parois de 13 souches de Conidiobolus coronatus et de 1 souche de Conidiobolus incongruus a été étudiée par chromatographie en phase gazeuse. Deux sucres principaux ont été mis en évidence: du glucose et du mannose. L'étude du rapport mannose/ glucose montre que les souches se répartissent en 3 groupes. Dans le premier groupe figurent les souches de C. coronatus ayant un rapport compris entre 0,92 et 1,3; ces souches ont été isolées de l'homme et du chimpanzé. Dans le second groupe figurent les souches de C. coronatus isolées du sol ou des lésions du cheval dont le rapport varie de 2,7 à 4,1; enfin, à part, Conidiobolus incongruus qui est caractérisé par un rapport de 0,44. La température léthale de chacune des souches étudiées ainsi que la présence éventuelle de spores villeuses est également signalée. Deux séries apparaissent donc chez Conidiobolus coronatus qui correspondent peut-être à des groupes biologiques différents.
The composition in the cell wall sugars of 13 strains of Conidiobolus coronatus and 1 strain of Conidiobolus incongruus has been determined. Glucose and mannose were found to be the main sugars. The study of the ratio mannose/glucose has shown that there are 3 groups of strains. The first group which contains the strain of C. coronatus isolated from man or chimpanzee is characterized by a ratio lying between 0.92 and 1.3. The second group containing the strains of C. coronatus isolated from horse lesion or from soil is characterized by a ratio lying between 2.7 and 4.1. The last group which contains C. incongruus whose ratio mannose/glucose is 0.44. These results suggest the existence of two groups among the strains of C. coronatus. Lethal temperature of each strain and eventual presence of villosus spores are also mentioned.相似文献
5.
From Senecio galpinii six new highly oxygenated germacrene derivatives were isolated, while S. coronatus afforded in addition to known cacalol derivatives two new ones. This species also contained a rare tricyclic sesquiterpene angelate, so far only isolated from one species. From the aerial parts of S. pleistocephalus an angelate derived from cadinene was isolated, while Lordhowea insularis (Benth.) B. Nord. afforded farnesyl angelate, which was reported previously. The structures were elucidicated mainly by high field 1H NMR spectroscopy. 相似文献
6.
Mamoru Yabe 《Ichthyological Research》1992,38(4):361-366
A new cottid species,Porocottus coronatus, is described on the basis of nine specimens from the Pacific coast of eastern Hokkaido, Japan. It differs from other species of this genus by having a group of finger-like cirri on the dorsal midline of the head, long uppermost preopercular spine, 15–16 anal fin rays and well developed cephalic sensory system with many small pores. 相似文献
7.
Female social dominance is rare in mammals, but common in lemurs. We investigated social dominance in two Eulemur species; the polygynous crowned lemur (E. coronatus) and the monogamous red‐bellied lemur (E. rubriventer), using four and two social groups, respectively. We collected data on agonistic interactions and two types of affiliative behavior (grooming and maintaining spatial proximity). We used a combination of focal watches of individuals, instantaneous scan‐sampling of groups, and all‐occurrence of some behaviors in groups. We found that overall rates of agonistic interactions were higher in E. coronatus, and they also had more decided intersexual agonistic interactions than E. rubriventer. However, in both species the females won the vast majority of these agonistic interactions. E. coronatus females were groomed more often by males than vice versa, whereas no sex differences in grooming were observed in E. rubriventer. We found that males were responsible for maintaining spatial proximity in E. coronatus whereas in E. rubriventer, females were responsible. In one group of E. coronatus, the male was overweight and dominant to the female and this is the first observation of male dominance in a lemur species typically described as female dominant. We suggest that body weights in captivity be monitored for maintaining normal dominance relationships. Overall, agonistic behaviors were consistent with clear female social dominance in both E. coronatus and E. rubriventer. The affiliative behaviors also provided clear evidence for female dominance E. coronatus, but not for E. rubriventer. Zoo Biol 0: 1–14, 2007. © 2007 Wiley‐Liss, Inc. 相似文献
8.
Tick-Borne Zoonotic Bacteria in Wild and Domestic Small Mammals in Northern Spain 总被引:2,自引:0,他引:2
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J. F. Barandika A. Hurtado C. García-Esteban H. Gil R. Escudero M. Barral I. Jado R. A. Juste P. Anda A. L. García-Prez 《Applied microbiology》2007,73(19):6166-6171
The prevalence and diversity of tick-borne zoonotic bacteria (Borrelia spp., Anaplasma phagocytophilum, Coxiella burnetii, and spotted fever group rickettsiae) infecting 253 small mammals captured in the Basque Country (Spain) were assessed using PCR and reverse line blot hybridization. Trapping sites were selected around sheep farms (study 1, 2000 to 2002) and recreational parks (study 2, 2003 to 2005). The majority of the studied mammals (162) were wood mice (Apodemus sylvaticus), but six other different species were also analyzed: yellow-necked mice (Apodemus flavicollis), shrews (Crocidura russula and Sorex coronatus), bank voles (Clethrionomys glareolus), domestic mice (Mus domesticus), and moles (Talpa europaea). The results showed an infection rate ranging from 10.7% to 68.8%, depending on the small mammal species. One C. russula shrew and one A. sylvaticus mouse gave positive reactions for A. phagocytophilum, and C. burnetii was detected in two domestic mice and one A. sylvaticus mouse in a farm. The DNA of Borrelia spp. was detected in 67 animals (26.5%), most of them presenting positive hybridization with the probe for Borrelia sp. strain R57, the new Borrelia species previously detected in small mammals in our region. Furthermore, a second PCR and reverse line blot hybridization specific for B. burgdorferi sensu lato revealed the presence of Borrelia afzelii in 6.3% of C. glareolus voles and 14.3% of S. coronatus shrews. All small mammals were negative for spotted fever group rickettsiae. These results highlight the relevance of small mammals as reservoirs of some zoonotic bacteria. 相似文献
9.
Runhua Lei Susie M. McGuire Gary D. Shore Edward E. LouisJr Rick A. Brenneman 《Conservation Genetics》2008,9(4):999-1002
The crowned sifaka (Propithecus deckeni coronatus) is found between the Mahavavy the Betsiboka Rivers in either Anjahamena or Antrema Classified Forest. The crowned sifaka
is endangered due to the loss and fragmentation of its natural habitat by deforestation. Twenty polymorphic nuclear microsatellite
loci were isolated from genomic DNA derived from a P. d. coronatus from Anjahamena, Madagascar. Population genetic parameters were estimated on 10 individuals sampled from Anjahamena, Madagascar,
to determine marker utility and preliminary baseline values to study the species’ genetic diversity and phylogeography. In
a cross-amplification test, each marker in the suite was informative in P. d. deckeni. 相似文献
10.
Hossein Barani‐Beiranvand Mansour Aliabadian Martin Irestedt Yanhua Qu Jamshid Darvish Tamás Székely René E. Van Dijk Per G. P. Ericson 《Journal of avian biology》2017,48(7):932-940
Penduline tits (Remiz spp.) are renowned for their diverse mating and parenting strategies, and are a well‐studied system by behavioural ecologists. However, the phylogenetic relationships and species delimitations within this genus are poorly understood. Here, we investigate phylogenetic relationships within the genus Remiz by examining the genetic variation in the mitochondrial cytochrome‐b gene of 64 individuals and in ten autosomal microsatellite markers from 44 individuals. The taxon sampling includes individuals from all currently recognized species (R. pendulinus, R. macronyx, R. coronatus, and R. consobrinus) and most subspecies in the Palearctic region. We showed that R. coronatus and R. consobrinus are genetically well differentiated and constitute independent evolutionary lineages, separated from each other and from R. pendulinus/macronyx. However, we found no evidence for significant differentiation among R. pendulinus/macronyx individuals in mtDNA haplotypes and only marginal differences between R. pendulinus and R. macronyx in microsatellite markers. Hence, based on present data our recommendation is to treat R. pendulinus and R. macronyx as conspecific and R. coronatus and R. consobrinus as separate species. 相似文献
11.
Distribution,occurrence and characterization of entomopathogenic fungi in agricultural soil in the Palestinian area 总被引:1,自引:0,他引:1
The occurrence of entomopathogenic fungi was investigated in irrigated vegetable fields and citrus orchards soils, over a nine-month period (April-December 1999),using the Galleria bait method (GBM). Entomopathogenic fungi were found to occur in 33.6% of the soil samples studied, with positive samples yielding 70 fungal isolates, belonging to 20 species from 13 genera. Conidiobolus coronatus was the most frequent and abundant entomopathogenic species recovered, comprising 31.4% of the total number of isolates. Soil pH, soil moisture content and the geographical location had minor or no effect on the isolation of entomopathogenic fungi in the fields studied. On the other hand, organic matter content of soil, and vegetation type were found to significantly affect the occurrence of entomopathogenic fungi in soil habitats, with orchard fields yielding larger numbers of isolates than vegetable fields. Using Koch's postulates the pathogenicity of fungal isolates to Galleria larvae was found to range from 16–100% (mortality rate). Isolates of C. coronatus proved to be the most virulent isolates recovered. The effect of media and temperature on mycelial growth rate, conidial production and conidial germination of six entomopathogenic fungal species (C. coronatus, Entomophaga grylli, Erynia castrans, Hirsutella jonesii, Paecilomyces farinosus and Sporodiniella umbellata) was also studied. Mycelial growth rate, spore production and spore germination were significantly affected by media, temperature and isolates. In view of the present results, C. coronatus appears to be a good candidate for pest control in agricultural soils, as it has a wide tolerance to agricultural practices, has frequently been isolated from both vegetable and orchard fields, and is characterized by high mycelial growth rate, conidial production and conidial germination.This revised version was published online in October 2005 with corrections to the Cover Date. 相似文献
12.
Fernando Mercado Malabet Heather Peacock Jeremi Razafitsalama Christopher Birkinshaw Ian Colquhoun 《American journal of primatology》2020,82(4):e23125
Due to the impact of anthropogenic activities on forest extent and integrity across Madagascar, it is increasingly necessary to assess how endangered lemur populations inhabiting human-dominated forest fragments can effectively sustain themselves ecologically. Our research addresses this concern by exploring how the distribution patterns of a small population of crowned lemurs (Eulemur coronatus), occupying a degraded forest fragment at Oronjia Forest New Protected Area in northern Madagascar, are impacted by the availability of key ecological and anthropogenic factors. We hypothesize that the distribution of E. coronatus within the fragment is limited by the availability of critical ecological resources and conditions and the intensity of anthropogenic features and activities. To examine this, we used MaxEnt to develop a species distribution model using presence-only occurrence records and 10 independent background covariates detailing the site's ecological and anthropogenic aspects. The results indicate that the realized distribution patterns of E. coronatus within human-dominated forest fragments are strongly associated with sections of forest that contain sparsely and sporadically distributed resources, such as freshwater and continuous hardwood vegetation. We conclude that the distribution of E. coronatus at Oronjia is shaped by their need to maximize foraging opportunities in a degraded forest landscape where they are subject to both environmental and anthropogenic stressors. 相似文献
13.
14.
15.
《Fungal Ecology》2008,1(1):33-39
A novel method is described for the extraction and presentation of mixed arthropods from litter as targets for potentially pathogenic species of Conidiobolus and Basidiobolus (Zygomycetes: Entomophthorales). All arthropods and test fungi (except C. nr. pumilus from broad leaf litter) were from the same larch (Larix) plantation. For 8 fungus species a bioassay (and repeat), were followed by survivorship comparison tests; Breslow, Logrank (Mantel-Heinszel/Peto) and Wilcoxon (Gehan/Lee-Desau). These were applied to test and control data separately for collembola and mites. Kaplan-Meier plots of Hazard Function were made. Of possible pathogenic effects the most marked was the high mortality of collembola and mites when showered with conidia of C. coronatus. Conidiobolus thromboides (collembola and mites) and C. osmodes (mites only) were associated with enhanced death in one of their two bioassays. Of the other 5 test species, C. adiaeretus and C. iuxtagenitus gave no indication of pathogenicity; nor did C. lamprauges, C. heterosporus and C. pumilus. Ecological implications are briefly discussed. 相似文献
16.
Pierre Taberlet Luca Fumagalli Jacques Hausser 《Evolution; international journal of organic evolution》1994,48(3):623-636
The shrews of the Sorex araneus group have undergone a spectacular chromosome evolution. The karyotype of Sorex granarius is generally considered ancestral to those of Sorex coronatus and S. araneus. However, a sequence of 777 base pairs of the cytochrome b gene of the mitochondrial DNA (mtDNA) produces a quite different picture: S. granarius is closely related to the populations of S. araneus from the Pyrenees and from the northwestern Alps, whereas S. coronatus and S. araneus from Italy and the southern Alps represent two well-separated lineages. It is suggested that mtDNA and chromosomal evolution are in this case largely independant processes. Whereas mtDNA haplotypes are closely linked to the geographical history of the populations, chromosomal mutations were probably transmitted from one population to another. Available data suggest that the impressive chromosome polymorphism of this group is quite a recent phenomenon. 相似文献
17.
I. Eitminaviciute 《Entomological Review》2006,86(2):S136-S146
The seasonal dynamics of microarthropods in anthropogenic soils was studied in the central lawns of roundabout junctions in the city of Vilnius. The microarthropod communities were found to suffer from the impact of automobile exhausts: their abundance was minimum at the curb and increased significantly at a distance of 10 m from it (at the center of a lawn), but it did not reach the values typical of the soil of the control plot. The dynamics of the microarthropod abundance in anthropogenically disturbed and control soils were similar, with the abundance of microarthropods increasing in the autumn-winter period (October–December). The microarthropod communities formed in the anthropogenic soils were unstable, with a high level of dominance of a few species. Oribatids Scutovertex minutus and Tectocepheus velatus, the gamasid mite Rhodacarus coronatus, and the springtail Brachystomella parvula proved to be well adapted to alkaline soils. 相似文献
18.
James K. Wetterer 《Oecologia》1995,104(4):409-415
I compare forager size and foraging ecology of the leaf-cutting ant Acromyrmex coronatus (Fabricius) with published data on three other leaf-cutter species in Costa Rica, Atta cephalotes (L.), Acromyrmex octospinosus (Reich), and Acromyrmex volcanus Wheeler. Intra-and interspecific differences in forager size in these leaf-cutting ants appear to reflect the economics of harvesting different preferred resources. Ac. coronatus colonies have relatively small foragers (mean mass=3.4±1.4 mg) that cut almost exclusively the thin, soft leaves and other parts of small herbaceous plants. Similarly, small A. cephalotes colonies have small foragers (3.3±1.0 mg) that attack the leaves of small herbaceous plants. In contrast, mature A. cephalotes colonies have a wider sizerange of foragers (7.3±4.1 mg) that primarily attack the leaves of trees, with larger foragers cutting thicker, tougher leaves. In A. cephalotes, the match of forager size to leaf type (both ontogenetically and behaviorally) increases foraging efficiency. Extreme forager polymorphism in mature A. cephalotes colonies appears to broaden the diversity of tree species that they can exploit efficiently. Ac. octospinosus and Ac. volcanus both have large, relatively monomorphic foragers (13.3±4.2 mg and 30.6±4.3 mg, respectively) that typically scavenge for pieces of fallen vegetation, such as dead leaves, fruit, and flowers, in addition to cutting herbs. The large foragers of Ac. octospinosus and Ac. volcanus appear to be well suited as generalist foragers, able to cut or collect any desirable vegetation encountered. Ac. coronatus is similar to A. cephalotes in other ways. Both Ac. coronatus and A. cephalotes establish and maintain cleared trunk trails for foraging, and both have minima workers that hitchhike on the loads carried by foragers, apparently serving to protect the larger foragers from attack by phorid flies. Trunk trails and hitchhikers are not known for Ac. octospinosus and Ac. volcanus. That A. coronatus and A. cephalotes show little overlap in geographic distribution within Costa Rica may relate both to differences in habitat requirements and to interspecific competition. 相似文献
19.
Mieczys?awa I. Bogu? Maria Czygier El?bieta K?dra Joanna Mazgajska Wioletta Wieloch 《Experimental parasitology》2010,125(4):400-1118
Eighteen fatty acids identified in the cuticle of three insect species representing differing susceptibilities to C. coronatus infection, were tested for effects on the in vitro growth and pathogenicity of the parasitic fungus. At all applied concentrations (0.1-0.0001% w/v) growth was inhibited by C16:0, C16:1, C18:0, C18:1, C18:2, C18:3, C20:0 and C20:1. At high concentrations spore germination was inhibited by C7:0, C8:0, C9:0, C10:0, C12:0, C18:2 and C18:3 and hyphal growth was merely retarded by C5:0, C6:0, C6:2, C14:0, C16:0, C16:1, C18:0, C18:1, C20:0 and C20:1. The presence of C15:0 at the 0.1% concentration stimulated growth of C. coronatus. Sporulation was inhibited by all concentrations of C16:0 and C18-20 fatty acids. Low concentrations of C5:0, C6:0, C6:2 and C7:0 enhanced sporulation. Fatty acids C5-12 as well as C18:3, C20:0 and C20:1 decreased the ability of fungal colonies to infect G. mellonella while C16:1 elevated it thus suggesting that C16:1 may stimulate production of enzymes involved in the host invasion. Toxicity of metabolites released into incubation medium decreased with varying degrees in the presence of C6:0, C6:2, C7:0, C9:0, C12:0, C16:1, C18:2, C18:3, C20:0 and C20:1; other fatty acids had no effect. Further work is needed to analyse the effects of exogenous fatty acids on the C. coronatus enzymes implicated in fungal pathogenicity as well as on the production of insecticidal metabolites. 相似文献
20.
Laboratory studies on the life-histories of four enchytraeid worms (Oligochaeta) which inhabit sewage percolating filters 总被引:5,自引:0,他引:5
M. A. LEARNER 《The Annals of applied biology》1972,70(3):251-266
The life-histories of four enchytraeid worms, Lumbricillus rivalis, Enchy-traeus coronatus, E. buchholzi, and E. albidus which occur in sewage percolating filters, were studied under laboratory conditions at 8 , 15 and 20°C. The number of ova per cocoon varied from 0 to 50 (L. rivalis), 0 to 33 (E. coronatus), 1 to 9 (E. buchholzi) and 0 to 22 (E. albidus). The mean number of ova per cocoon was highest at 15°C for all species except E. coronatus which had a highest mean value at 8°C. The number of ova in cocoons was correlated with cocoon length (P < 0.001) for all species. Cocoon production usually increased with temperature ranging from 0.8 cocoons per adult per week at 8°C to 2.0 at 20°C for L. rivalis, and from 1–4 to about 2.6 for E. coronatus and E. buchholzi. The total number of ova produced by each E. coronatus (350 at 8°C to 550 at 20°C) was similar to that produced by each L. rivalis (600 at 8°C to 350 at 20°C) and was about five times greater than the total numbers produced by the other two species. Cocoon and ova production and the number of ova per cocoon varied with the age of the adult, usually reaching a peak soon after maturity. Hatching success was low and generally 40–50 % of ova failed to develop; subsequent mortality among immature worms was about 10–20%. Growth was more rapid at the higher temperatures; L. rivalis matured in about 26 days at 20°C, the clitellum forming when the worm was 13–14 mm long; data for the other species are 13 days and 5–6 mm (E. coronatus); 16 days and 3–4 mm (E. buchholzi); 28 days and 13–14 mm (E. albidus). The maturation period at 8°C was at least twice that at 20°C. The generation period (cocoon to cocoon) was about a month at 20°C for all species except E. albidus (2 months), but as some species had longer reproductive periods than others the actual number of generations per year was highest in E. buchholzi, 7.0 per year, and lowest in E. albidus, about 3.3 per year, At 8°C all four species had between 1.4 and 2.8 generations a year. A comparison of expected and observed population densities of L. rivalis and E. coronatus in a sewage percolating filter showed that neither achieved values approaching their potential summer densities although ample food was apparently available. Of the four species studied only E. buchholzi produced viable ova without pairing. 相似文献