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1.
The taxonomic composition of bacteria associated with two species of tetrodotoxin-bearing (TTX-bearing) (Hubrechtella juliae and Lineus alborostratus) and two species of non-TTX-bearing (Quasitetrastemma stimpsoni and Malacobdella grossa) ribbon worms collected from the Peter the Great Bay of Sea of Japan was studied. Bacterial isolates were identified using 16S rRNA gene sequencing and phenotypic characteristics. Thirty-eight strains of heterotrophic bacteria from the eight genera: Pseudoalteromonas, Shewanella, Ruegeria, Pseudomonas, Defluviicoccus, Vibrio, Alteromonas, and Bacillus, were isolated and characterized. γ-Proteobacteria dominated among the associated microflora of nemerteans (76.3% of the total number of isolates). Sensitivity analysis of 38 strains to antibiotics of various classes revealed multiple resistance to three or more antibiotics in all of the studied isolates. The 15 bacterial strains isolated in the study exhibited antimicrobial activities against at least one of five indicator microorganisms, most of which corresponded to the Pseudoalteromonas genus. Screening of the TTX-producing bacteria was performed using confocal laserscanning microscopy and polyclonal antibodies. A TTX-producing strain, Pseudoalteromonas sp., was found in the nemertean H. juliae. A correlation between the presence of TTX-positive microflora and the toxicity of nemerteans was determined.  相似文献   

2.
Pachyphlodes (Pezizaceae) is a genus of truffle-like fungi that is distributed across the Northern Hemisphere. These fungi form ectomycorrhizae primarily with trees in the Fagaceae family, and occasionally with other host plants. The genus Plicariella (= Scabropezia) is phylogenetically inferred as an ally of, or within, the Pachyphlodes lineage. Despite molecular phylogenetic analyses that show the close relationships of species in these two genera, morphological differences in ascomata shape and color, spore ornamentation, and ascus shape are profound. Here, we studied spore wall development to better understand affinities within the PachyphlodesPlicariella lineages. Electron microscopy studies indicate that the initial spore wall development is similar across six Pachyphlodes species and a Plicariella species, despite striking differences in mature spore ornamentation among species. Ultrastructural analyses reveal that differences in spore ornamentation among Pachyphlodes species are due to unique developmental events at the final stages of spore wall deposition. Septal pore ultrastructure in Pachyphlodes species is similar to other Pezizaceae that have been studied. Molecular analyses of the five species studied indicate that four of them have not been previously described. The new species Pachyphlodes annagardnerae is here described, and the ultrastructural features of species of Pachyphlodes, Plicariella, and other Pezizales are compared and discussed.  相似文献   

3.
Two species of the interstitial nemerteans from the intertidal zone of Van Phong Bay (southern Vietnam) are described. By the structure of the proboscis and statocysts, the nemertean Ototyphlonemertes ani sp. n. can be referred to the species group “Lactea” (sensu Envall, Norenburg, 2001), but it differs from other species of this group by the presence of cerebral organs and caudal cirri. The second species new for the region is very similar to O. martynovi, but differs from it in having 2 to 3 cephalic cirri in group C (instead of 4 to 6 cirri found in O. martynovi).  相似文献   

4.
5.
We assembled a dataset tabulating the weights of Thai and Indonesian mangrove trees that we measured between 1982 and 2001. We selected four Thai study sites in Phang Nga, Ranong, Satun, and Trat Provinces and one site in eastern Indonesia on Halmahera Island in Maluku Province. The stands in Ranong Province and on Halmahera Island were in primary forests with data collected in the 1980s and the remaining stands were in secondary forests with data collected later. We collected 124 tree samples from ten species (Avicennia alba, Bruguiera cylindrica, B. gymnorrhiza, Ceriops tagal, Rhizophora apiculata, R. mucronata, Sonneratia alba, S. caseolaris, Xylocarpus granatum, and X. moluccensis) and measured the root weights of 32 individuals of nine species (A. alba, B. cylindrica, B. gymnorrhiza, C. tagal, R. apiculata, R. mucronata, S. alba, S. caseolaris, and X. granatum). All sampled trees were subjected to a standardized protocol to obtain aboveground weights. The trunks were divided into horizontal segments from which the leaves and branches were collected separately. Roots were collected by winching them out of the ground, by trench digging, or by complete excavation. Thus, we were able to compile the weights of the trunk, branches, leaves, and roots of each tree sampled. Aerial roots were included in root weight measurements, although they were collected above ground. We compiled separate lists of trunk diameters, trunk heights, heights of the lowest living branches, and the heights of aerial roots on the trunks of trees in different size categories. Our dataset includes a wide range of tree sizes (maximum trunk diameter 48.9 cm), geographical locations (1°10′N–12°24′N, 98°32′E–123°49′E) and organ weights (trunks, branches, leaves, and roots), and therefore should prove useful in future biomass studies of mangrove forests.  相似文献   

6.
7.
Morphological traits are useful to investigate insect sex-related differences in body size and to reveal differences in resource use. It has been suggested that as the resource increases, so does the body size of organisms interacting with the resource, highlighting the crucial role of resource quality and quantity in determining the morphological traits of organisms interacting with the resource. Here, we describe morphological traits of two species of Bruchinae, Merobruchus terani (Kingsolver 1980) and Stator maculatopygus (Pic 1930), consuming seeds of Senegalia tenuifolia (Fabaceae: Mimosoideae). We evaluated the influence of monthly sample and sampling sites on tibia and femur length and biomass. In addition, we tested two predictions in which body size related to resource amount and body size related to longevity. Males of M. terani were heavier than females, whereas the two sexes of S. maculatopygus did not differ in biomass. Both species had larger body sizes in the late ripe-fruit stage. With respect to sampling sites, biomass of M. terani did not differ, whereas S. maculatopygus did differ in biomass. Merobruchus terani showed a positive relationship with seed traits, whereas S. maculatopygus showed no relationship. At the same time, fruit traits showed a negative effect on morphological traits for both beetle species. The longevity experiment, performed using only M. terani, showed an equal longevity and seed consumption rate for both sexes. Our study indicates that different species, interacting in the same system and performing similar functional behaviors, respond differently to the same resource.  相似文献   

8.
Based on a complex approach including morphological and molecular genetic methods, the taxonomic position of two casebearer moth species Coleophora tsherkesi Falkovitsh, 1970 and C. isabellina Falkovitsh, 1970 (Lepidoptera, Coleophoridae) is discussed. On the phylogenetic tree based on the cytochrome oxidase subunit I gene (COI), two species form a common cluster with species of the genera Ionescumia, Carpochena, and Goniodoma. Data on the molecular phylogeny and morphology justify the placement of Coleophora tsherkesi and C. isabellina in a separate genus Falkmisa Anikin et Dyomin, gen. n. Thus, the tribe Carpochenini includes three genera: Ionescumia, Carpochena, and Falkmisa.  相似文献   

9.
One of the most enigmatic and unusual groups in the passionflower genus, Passiflora section Dysosmia (Passifloraceae), stands out as a group that is notoriously taxonomically complicated. Phenetic and cladistic analyses of Dysosmia were carried out with representatives from all 21 species currently recognized in the section, in order to delineate morphological groups above the species level. The study was based mainly on vegetative morphological characters and included principal coordinates, non-metric multidimensional scaling, cluster, and cladistic analyses. Results from each analysis reveals that three major species assemblages exist within Dysosmia, corresponding largely to vegetative pubescence and fruit color. The results presented here set the stage for future systematic and phylogenetic studies in Passiflora sect. Dysosmia.  相似文献   

10.
Karyotypic features as well as larval and imaginal morphology have been studied in five species of the black fly genus Wilhelmia, viz. W. equina (Linnaeus, 1758), W. pseudequina (Seguy, 1921), W. lineata (Meigen, 1804), W. veltistshevi (Rubzov, 1940), and W. salopiensis (Edwards, 1927). Photomaps of polytene chromosomes are given for all species (those for W. pseudequina and W. veltistshevi, for the first time). Species-specific karyological and morphological characters have been revealed. According to principal karyological features, the species examined are divided into the equina and salopiensis groups. The validity of the species rank is confirmed for all species. Clear karyological and morphological distinctions between W. salopiensis and W. lineata give evidence that synonymization of W. salopiensis with W. lineata was erroneous.  相似文献   

11.
A new species of Phellinus sensu stricto was isolated from diseased Vitis vinifera in the Northern Cape and Limpopo provinces of South Africa. Phellinus resupinatus is described here based on fruit body morphology, internal transcribed spacer (ITS) and large subunit (LSU) phylogenies. Phellinus resupinatus forms a well-supported clade closely related to Phellinus bicuspidatus, a species associated with white rot in oak trees in the United States. Morphologically, P. resupinatus is characterised by its resupinate fruit body shape, straight, ventricose hymenial setae and broadly ellipsoid hyaline basidiospores. It has been isolated from esca-diseased grapevines in the summer rainfall regions of South Africa and is found on the uppermost trunks of declining vines showing symptoms of white rot.  相似文献   

12.
Three species currently addressed to Protohydnum (Auriculariales) are studied with morphological and DNA methods. The genus Protohydnum is retained for the type species only, P. cartilagineum, recently re-collected in Brazil. The European species, P. piceicola, is not congeneric with P. cartilagineum and, therefore, placed in its own genus, Hyalodon, gen. nov. Another Hyalodon species, H. antui, is described from East Asia. The third member of Protohydnum sensu lato, P. sclerodontium from South-East Asia, is transferred to Elmerina.  相似文献   

13.
An annotated list of larvae (metacestodes) of gryporhynchid tapeworms (Cestoda: Cyclophyllidea) from freshwater fishes in Africa is provided with numerous new host and geographical records. Newly collected materials from Burundi, Democratic Republic of the Congo, Kenya, Madagascar, Namibia, Senegal, South Africa, Sudan and Zimbabwe practically double the total number of species reported from African fish so far. We confirm the occurrence of 16 species (five unidentified to the species level and most likely representing new taxa) belonging to the genera Amirthalingamia Bray, 1974 (1 species), Cyclustera Fuhrmann, 1901 (2 species), Dendrouterina Fuhrmann, 1912 (1 species), Neogryporhynchus Baer & Bona, 1960 (1 species), Paradilepis Hsü, 1935 (4 species), Parvitaenia Burt, 1940 (5 species), and Valipora Linton, 1927 (2 species). Additionally, metacestodes of four unidentified species of Paradilepis and Parvitaenia are reported from fish for the first time. Rostellar hooks of all species are illustrated and their measurements are provided together with a host-parasite list. The molecular phylogenetic analysis based on partial LSU rDNA sequences offers the first insight into the internal phylogenetic relationships within the family. Together with the morphological observations, the present study provides a taxonomic baseline for future studies on this largely neglected, but widely distributed and relatively frequent, group of parasites of African fishes, including economically important cichlids like tilapias and cyprinids.  相似文献   

14.
In connection with the problems of identification of certain species of the genus Ponticola, and especially their juveniles, morphological and genetic studies of gobies collected in the northwestern part of the Black Sea basin were carried out using literature data and museum collections. Karyological data indicate a distinct species status of western (P. odessicus) and eastern (P. eurycephalus) mushroom gobies; the range of the latter includes not only the Sea of Azov but also waters of the Black Sea coast of the Crimean Peninsula; these conclusions are supported by preliminary molecular genetic studies. Based on the obtained results of intraspecific morphological variability of species, we propose morphological characteristics for identification of adult P. syrman and P. odessicus, as well as a specific set of characteristics to identify juvenile (body length less than 50 mm) P. syrman, P. kessleri, and P. odessicus. We reveal differences in the karyotype structure of P. syrman from populations of the Sasyk Lake and the Don River, which do not differ in terms of external morphological characteristics and variability of cytochrome b haplotypes. The need for further research of phylogeography and morphological and karyological variability of P. syrman sensu lato is assumed.  相似文献   

15.
The faunas living in the vast deep sea regions around the Antarctic are very poorly known. This is especially true for the biodiversity of polychaetes inhabiting these remote areas. Therefore, we report new morphological data of Glyceriformia from the ANDEEP cruises to the South Atlantic Ocean and the Southern Ocean. Based on benthos samples from three expeditions aboard R/V POLARSTERN, two species of Glyceridae (Glycera capitata, G. diva) and four species of Goniadidae (Bathyglycinde sibogana, B. stepaniantsae, Goniada maculata, Progoniada regularis) were studied. Furthermore, new morphological details (especially for the previously unknown tail) for the rarely found taxon B. stepaniantsae are given. The distribution patterns of the different taxa demonstrated that some species have a high dispersal capability and show an extended level of eurybathy, whereas other species are restricted to the deep sea.  相似文献   

16.
The study of the cell wall structure was performed for ten species of Euastrum: E. ansatum (Ehrenb.) Ralfs, E. bidentatum Näg., E. binale (Turp.) Ehrenb. ex Ralfs, E. dubium Näg., E. elegans (Bréb.) Kütz. ex Ralfs, E. germanicum (Schmidle) W. Krieger, E. oblongum (Grev.) Ralfs ex Ralfs, E. pectinatum Bréb. ex Bréb. in Ralfs, E. validum West et G.S.West, E. verrucosum (Ehrenb.) ex Ralfs. The investigation of the cell wall ultrastructure has established for the first time that the pore canal in 6 of 10 species always has a coiled form to some degree. Three species (E. germanicum, E. pectinatum, and E. verrucosum) have both coiled and straight canals, and E. ansatum has only straight ones. A new type of pores (P7), typical only for representatives of the genus Euastrum, was also noted. In addition, a simple and effective method of preparing desmidium algal cells for investigation with transmission electron microscope has been developed.  相似文献   

17.
In Brazil, although a large number of animals are used in traditional medicine (at least 354 species), information about their biological activities is scarce. In this context, the objective of this study was to evaluate the bactericidal potential of zootherapeutic by-products from animals used in Brazilian traditional medicine and discuss the ecological and cultural consequences of such practices. The species analyzed were: Tupinambis merianae (skin), Iguana iguana (skin and body fat), Crotalus durissus (skin and body fat), Boa constrictor (skin), Euphractus sexcinctus (body fat) and Coendou prehensilis (quills). Experiments were performed with standard clinical strains of Escherichia coli (EC-ATCC10536) and Staphylococcus aureus (SA-ATCC 25923). For the microbiological assay, the zootherapeutics were evaluated using serial microdilutions. The results indicate that none of the samples possess inhibitory activity against standard bacterial strains. The in vitro ineffectiveness of the analyzed products demonstrate a necessity for new pharmacological research that encompass a large number of species of medicinal animals as well as highlight the importance of zootherapy in the context of plans for animal conservation.  相似文献   

18.
During investigation of the mycobiota in the Sea of Okhotsk, three new Penicillium species were isolated from subaqueous soils collected in the Sakhalin Gulf and in the northeastern part of the Sakhalin shelf, near the Piltun Bay. According to Raper and Thom’s classification, the newly described species P. piltunense, P. ochotense, and P. attenuatum belong to subsection Divaricata. Two analyses were performed to reveal the phylogenetic relationships of the putative new species with other Penicillium species. Phylogenetically, the new species are related to the members of the P. canescens group and share some morphological and physiological features with them. However, they differ in having a larger colony diameter that makes them similar to P. atrovenetum, P. coralligerum, and P. antarcticum. A detailed analysis based on ITS, combined β-tubulin and calmodulin datasets, and morphological features revealed that the new species formed a distinct group inside the P. atrovenetum subclade. Moreover, P. attenuatum differs from the other two species macro- and micromorphologically and may represent a distinct phylogenetic lineage.  相似文献   

19.
Fungi associated with black point were isolated from three highly susceptible wheat genotypes in the North China Plain. The 21 isolates represented 11 fungal genera. The most prevalent genera were Alternaria (isolation frequency of 56.7%), Bipolaris (16.1%), and Fusarium (6.0%). The other eight genera were Curvularia, Aspergillus, Cladosporium, Exserohilum, Epicoccum, Nigrospora, Penicillium, and Ulocladium; their isolation frequencies ranged from 0.8 to 4.8%. The pathogenicity of the isolates was individually assessed in the greenhouse by inoculating wheat plants with spore suspensions. Ten of the 21 isolates caused significantly higher incidences of black point than that the controls. These isolates belonged to eight fungal species (A. alternata, B. sorokiniana, B. crotonis, B. cynodontis, C. spicifera, F. equiseti, E. rostratum, and E. sorghinum) based on morphological traits and phylogenetic analysis. The average incidences of black point in the eight fungal species were 32.4, 54.3, 43.0, 41.9, 37.2, 38.8, 50.1, and 34.1%, respectively. B. sorokiniana and A. alternata were determined to be the most important pathogens in the North China Plain based on fungal prevalence and symptom severity. This study is the first to identify E. rostratum as a major pathogen causing black point in wheat.  相似文献   

20.
Based on a morphological approach, five species of cyclocoelids (Digenea: Cyclocoelidae) are revised based on material from birds in Mexico. The species studied are: Cyclocoelum cf. leidyi Harrah, 1922 from the black-necked stilt Himantopus mexicanus Müller (Recurvirostridae); Cyclocoelum mutabile (Zeder, 1800) from the northern jacana Jacana spinosa L. (Jacanidae) and the willet Tringa semipalmata Gmelin (Scolopacidae); Cyclocoelum pseudomicrostomum Harrah, 1922 from the American coot Fulica americana Gmelin (Rallidae); Selfcoelum lamothei Blend & Dronen, 2008, from the long-billed curlew Numenius americanus Bechstein (Scolopacidae); and Neohaematotrephus arayae Zamparo, Brooks, Causey & Rodriguez, 2003 from J. spinosa. New morphological data, illustrations and measurements are presented for these trematodes. Three species, insufficiently described, i.e. C. cf. leidyi, C. mutabile and C. pseudomicrostomum, are redescribed in detail. Our results indicate morphological variation in some important features used in the diagnosis of Cyclocoelum Brandes, 1892 (i.e. the presence or absence of oral sucker, the position of the genital pore relative to the pharynx, and the posterior extension of the uterus) and Selfcoelum Dronen, Gardner & Jiménez, 2006 (i.e. anterior extension of vitelline follicles). Finally, this study provides the first molecular data for the large subunit of the ribosomal RNA (28S rRNA) gene for N. arayae.  相似文献   

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