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1.
A chub of previously ambiguous identity from the Boljunscica and Pazincica rivers (south-eastern Istra Peninsula) was studied and compared with geographically close Squalius squalus, Squalius zrmanja, and Squalius janae recently described from the Dragonja River drainage in the Adriatic Sea basin in Slovenia. It was shown that the chub from the south-eastern Istra Peninsula differs from all know species of Squalius but one: Squalius janae. Three samples examined from Boljunscica and Pazincica rivers and Squalius janae from its type locality, Dragonja River, show the following characters typical for the latter species: a long head (the head length 27–32% SL); a pointed conical snout with a clearly projecting upper jaw; a long straight mouth cleft, the lower jaw length (39–45% HL) exceeding the caudal peduncle depth; a large eye; commonly 9? branched anal-fin rays; commonly 44 total vertebrae (24+20 or 25+19); bright silvery colouration, scales easily lost; iris, pectoral, pelvic and anal fin pigmentation with yellow shades. The data on the distribution of Squalius chubs in the northern Adriatic basin support the assumption that the range of Squalius janae is determined by the geology of the Trieste Flysch Basin and the Pazin Flysch Basin forming the base of the Istra Peninsula. The distribution pattern of this species does not support a simple model of fish dispersal and a complete connectivity within the whole Palaeo-Po historical drainage. Indeed, it indicates a disrupted surface palaeohydrography that was heavily fragmented by karstification in the whole Dinaric area.  相似文献   

2.
The discipline taxonomy (the science of naming and classifying organisms, the original bioinformatics and a basis for all biology) is fundamentally important in ensuring the quality of life of future human generation on the earth; yet over the past few decades, the teaching and research funding in taxonomy have declined because of its classical way of practice which lead the discipline many a times to a subject of opinion, and this ultimately gave birth to several problems and challenges, and therefore the taxonomist became an endangered race in the era of genomics. Now taxonomy suddenly became fashionable again due to revolutionary approaches in taxonomy called DNA barcoding (a novel technology to provide rapid, accurate, and automated species identifications using short orthologous DNA sequences). In DNA barcoding, complete data set can be obtained from a single specimen irrespective to morphological or life stage characters. The core idea of DNA barcoding is based on the fact that the highly conserved stretches of DNA, either coding or non coding regions, vary at very minor degree during the evolution within the species. Sequences suggested to be useful in DNA barcoding include cytoplasmic mitochondrial DNA (e.g. cox1) and chloroplast DNA (e.g. rbcL, trnL-F, matK, ndhF, and atpB rbcL), and nuclear DNA (ITS, and house keeping genes e.g. gapdh). The plant DNA barcoding is now transitioning the epitome of species identification; and thus, ultimately helping in the molecularization of taxonomy, a need of the hour. The ‘DNA barcodes’ show promise in providing a practical, standardized, species-level identification tool that can be used for biodiversity assessment, life history and ecological studies, forensic analysis, and many more.  相似文献   

3.
The recent allocation of the cyprinid complex Squalius alburnoides to the genus Iberocypris in the Handbook of European Freshwater Fishes is refuted by confirming evidence of a close relationship with the genus Squalius. Squalius alburnoides is here defined as a complex based on the existence of a hybrid form with distinct genome combinations and ploidies and of a reconstituted nuclear non‐hybrid male form also with hybrid origin.  相似文献   

4.
5.
We provide a first investigation of fish species composition, sex ratios, age, length-weight relationships and growth models in Saghamo Lake located in Javakheti highland (Georgia). In total 713 specimens belonging to 8 species were collected included non-native Coregonus albula, Carassius gibelio and native Alburnoides bipunctatus, Squalius cephalus, Capoeta capoeta, Romanogobio persus, Salmo cf. caspius and Barbus lacerta, among which later two were recorded for the first time in the lake. In overall, relative abundances of all species is low while some species may not be presented with viable populations. Deviation from expected sex ratio, growth at age and age structure indicates severe anthropogenic pressure as a potential driver of fish community degradation in the lake.  相似文献   

6.
《Journal of Asia》2022,25(4):101989
DNA barcodes obtained from cytochrome c oxidase subunit 1 (cox1) offer a fast and easy way to identify a range of biological organisms. Culicoides (Diptera: Ceratopogonidae) are a group of small, blood sucking midges whose species are the vectors for some arboviruses, such as bluetongue virus, African horse sickness virus, epizootic hemorrhagic disease virus and equine encephalosis virus. Identification of these small insects is difficult so constructing DNA barcode libraries for species present in certain areas is helpful to clarify the taxonomy and assist non-specialist workers to identify species. In this study, we analysed specimens belonging to C. subgenus Hoffmania collected from 12 towns of Yunnan Province, China. Specimens were identified by morphology and processed to construct DNA barcodes. A total of 185 specimens referable to 6 morphological species were processed for cox1 and 28S rRNA sequencing. The resulting 185 cox1 sequences were assigned to 13 barcode index numbers (BINs) which include 9 novel BINs. Molecular and morphological evidence was used to support the transfer of 4 species previously assigned to C. subg. Avaritia into C. subg. Hoffmania. Molecular analysis revealed the presence of 7 potential cryptic species within C. innoxius, three within C. liui and two within C. insignipennis.  相似文献   

7.
This study represents the first comprehensive molecular assessment of freshwater fishes and lampreys from Germany. We analysed COI sequences for almost 80% of the species mentioned in the current German Red List. In total, 1056 DNA barcodes belonging to 92 species from all major drainages were used to (i) build a reliable DNA barcode reference library, (ii) test for phylogeographic patterns, (iii) check for the presence of barcode gaps between species and (iv) evaluate the performance of the barcode index number (BIN) system, available on the Barcode of Life Data Systems. For over 78% of all analysed species, DNA barcodes are a reliable means for identification, indicated by the presence of barcode gaps. An overlap between intra‐ and interspecific genetic distances was present in 19 species, six of which belong to the genus Coregonus. The Neighbour‐Joining phenogram showed 60 nonoverlapping species clusters and three singleton species, which were related to 63 separate BIN numbers. Furthermore, Barbatula barbatula, Leucaspius delineatus, Phoxinus phoxinus and Squalius cephalus exhibited remarkable levels of cryptic diversity. In contrast, 11 clusters showed haplotype sharing, or low levels of divergence between species, hindering reliable identification. The analysis of our barcode library together with public data resulted in 89 BINs, of which 56% showed taxonomic conflicts. Most of these conflicts were caused by the use of synonymies, inadequate taxonomy or misidentifications. Moreover, our study increased the number of potential alien species in Germany from 14 to 21 and is therefore a valuable groundwork for further faunistic investigations.  相似文献   

8.
9.
Stenotaenia is one of the largest and most widespread genera of geophilid centipedes in the Western Palearctic, with a very uniform morphology and about fifteen species provisionally recognized. For a better understanding of Stenotaenia species-level taxonomy, we have explored the possibility of using molecular data. As a preliminary assay, we sampled twelve populations, mainly from the Italian region, and analyzed partial sequences of the two genes COI and 28S. We employed a DNA-barcoding approach, complemented by a phylogenetic analysis coupled with divergence time estimation. Assuming a barcoding gap of 10–16% K2P pairwise distances, we found evidence for the presence of at least six Stenotaenia species in the Italian region, which started diverging about 50 million years ago, only partially matching with previously recognized species. We found that small-sized oligopodous species belong to a single clade that originated about 33 million years ago, and obtained some preliminary evidence of the related genus Tuoba being nested within Stenotaenia.  相似文献   

10.
Type E botulinum toxin (BoNT/E)-producing Clostridium butyricum strains isolated from botulism cases or soil specimens in Italy and China were analyzed by using nucleotide sequencing of the bont/E gene, random amplified polymorphic DNA (RAPD) assay, pulsed-field gel electrophoresis (PFGE), and Southern blot hybridization for the bont/E gene. Nucleotide sequences of the bont/E genes of 11 Chinese isolates and of the Italian strain BL 6340 were determined. The nucleotide sequences of the bont/E genes of 11 C. butyricum isolates from China were identical. The deduced amino acid sequence of BoNT/E from the Chinese isolates showed 95.0 and 96.9% identity with those of BoNT/E from C. butyricum BL 6340 and Clostridium botulinum type E, respectively. The BoNT/E-producing C. butyricum strains were divided into the following three clusters based on the results of RAPD assay, PFGE profiles of genomic DNA digested with SmaI or XhoI, and Southern blot hybridization: strains associated with infant botulism in Italy, strains associated with food-borne botulism in China, and isolates from soil specimens of the Weishan lake area in China. A DNA probe for the bont/E gene hybridized with the nondigested chromosomal DNA of all toxigenic strains tested, indicating chromosomal localization of the bont/E gene in C. butyricum. The present results suggest that BoNT/E-producing C. butyricum is clonally distributed over a vast area.  相似文献   

11.
The genus Aseptis McDunnough (Lepidoptera, Noctuidae, Noctuinae, Xylenini, Xylenina) is revised to include 15 species based on morphological and molecular data. Several new synonymies are introduced. In addition, two genera are described because of significant morphological differences from Aseptis: Paraseptis gen. n., and Viridiseptis gen. n., resulting in the new combinations Paraseptis adnixa (Grote), comb. n., and Viridiseptis marina (Grote), comb. n. Although this work is primarily based on morphological data, DNA sequence data for the 658-base pair “barcode” segment of the mitochondrial gene for subunit 1 of cytochrome c oxidase was used as a secondary support for taxonomic changes within Aseptis and for the two new genera. Our work should provide clarity and stability in a previously difficult genus.  相似文献   

12.
Total DNA of three species of Meloidogyne spp., including four subspecific races of M. incognita, were digested separately with EcoR I, Cla III, and Hind III and probed with ³²P-labelled total genomic DNA from M. incognita race 1 in Southern hybridizations. Short exposures of Southern blots after Hind III digestion revealed patterns that were useful for separating the species. Race differences were seen after longer exposures. The DNA fragment patterns obtained were scanned with a laser densitometer and the data were subjected to principal coordinate and cluster analyses. The likelihood of cloning species and race-specific DNA probes is discussed.  相似文献   

13.
Anatolian mountain frogs (Rana macrocnemis, Rana camerani, Rana holtzi, and Rana tavasensis) are one of the most specious amphibian groups in Turkey containing two endemic taxa (R. holtzi and R. tavasensis). The taxonomy of this group remains controversial as there are several unresolved issues.In the present study, we aimed to resolve the taxonomic uncertainty of the Anatolian mountain frogs through two mitochondrial genes (CYTB, 481 bp and COI, 743 bp) and two protein-coding nuclear genes (POMC, 401 bp and RAG1, 717 bp). The mitochondrial DNA (mtDNA) markers were found to be highly polymorphic in this group. Haplotype network analysis revealed that R. tavasensis was different for at least 33 and 52 mutational steps according to CYTB and COI gene regions, respectively. High bootstrap and posterior probability values obtained from the mtDNA genes support the idea that Anatolian mountain frogs are represented by two distinct species in Anatolia: R. macrocnemis and R. tavasensis. However, no genetic variation was detected according to nuclear DNA (nDNA) markers.The analysis of molecular variance (AMOVA) revealed no differences among the groups of R. macrocnemis, R. camerani, and R. holtzi. Despite the low genetic distance among R. macrocnemis, R. camerani, and R. holtzi species, the pairwise distances estimated from R. tavasensis were higher compared with other Anatolian mountain frog lineages.  相似文献   

14.
Entomopoxvirus (EPV) occlusion bodies were isolated from virus infected nymphs of the grasshoppers Melanoplus sanguinipes, Arphia conspirsa, and Phoetaliotes nebrascensis. Separation of the viral structural proteins by sodium dodecyl sulfate-polyacrylamide gel electrophoresis gave unique protein patterns for each of the three viruses. An occlusion body protein of approximately 100,000 MW was isolated from each virus. Cleavage of viral DNA with HinddIII and BamHI restriction endonucleases and separation of the fragments by agarose gel electrophoresis gave different DNA fragment patterns for each of the three entomopoxviruses. Molecular weight estimates of 120 × 106 for M. sanguinipes EPV DNA, 129 × 106 for A. conspirsa EPV DNA, and 125 × 106 for P. nebrascensis EPV DNA were calculated from the sizes of the viral DNA fragments. Approximately 55% base sequence homology was detected by Southern hybridization of α-32P-labeledM. sanguinipes EPV DNA with P. nebrascensis DNA. No base sequence homology was detected by Southern hybridization of labeled M. sanguinipes EPV DNA to Othnonius batesi EPV DNA (Coleoptera), Amsacta moorei EPV DNA (Lepidoptera), Euxoa auxiliaris EPV DNA (Lepidoptera), and vaccinia virus DNA fragments.  相似文献   

15.
Aquatic habitats are vulnerable to the invasion of alien species, so early warning protocols are necessary for eradication. The presence in Italy of two alien duckweeds in freshwaters has been documented: Lemna minuta, that showed high invasivity, and L. valdiviana, still confined to south Lazio. These two species may be mistaken for each other and for the domestic L. minor and L. gibba due to morphological variation. Here, we assess the applicability of DNA barcoding as a complement to morphological analysis for monitoring the spread of alien Lemna. We chose two chloroplast genome sequences for their ability to discriminate all Lemna species: the 5’ intron of the trnK gene and the matK gene. Among 48 samples of Lemna collected at 20 sites in Central Italy, 20 were identified as L. minor, 19 as L. minuta, five as L. trisulca and four as L. gibba. L. minuta was present at most sampling sites; in particular, at six locations of Lake Trasimeno, eight L. minuta samples were found. We demonstrate that DNA sequence analyses with cost-effective barcoding techniques can effectively support expert efforts in species determination for an early alert system of invasive Lemna species.  相似文献   

16.
The Mediterranean Basin has experienced extensive change in geology and climate over the past six million years. Yet, the relative importance of key geological events for the distribution and genetic structure of the Mediterranean fauna remains poorly understood. Here, we use population genomic and phylogenomic analyses to establish the evolutionary history and genetic structure of common wall lizards (Podarcis muralis). This species is particularly informative because, in contrast to other Mediterranean lizards, it is widespread across the Iberian, Italian, and Balkan Peninsulas, and in extra-Mediterranean regions. We found strong support for six major lineages within P. muralis, which were largely discordant with the phylogenetic relationship of mitochondrial DNA. The most recent common ancestor of extant P. muralis was likely distributed in the Italian Peninsula, and experienced an “Out-of-Italy” expansion following the Messinian salinity crisis (∼5 Mya), resulting in the differentiation into the extant lineages on the Iberian, Italian, and Balkan Peninsulas. Introgression analysis revealed that both inter- and intraspecific gene flows have been pervasive throughout the evolutionary history of P. muralis. For example, the Southern Italy lineage has a hybrid origin, formed through admixture between the Central Italy lineage and an ancient lineage that was the sister to all other P. muralis. More recent genetic differentiation is associated with the onset of the Quaternary glaciations, which influenced population dynamics and genetic diversity of contemporary lineages. These results demonstrate the pervasive role of Mediterranean geology and climate for the evolutionary history and population genetic structure of extant species.  相似文献   

17.
Tulasnella spp. are the main fungal symbionts of Brazilian Epidendrum orchids. The taxonomy of these fungi is largely based on ITS rDNA similarity, but culture dependent techniques are still essential to establish the true biological entity of the mycobiont. The aim of this study was to characterize morphologically and molecularly 16 Tulasnella spp. fungi isolated from three different populations of E. secundum and to test the coincidences between morphological and molecular characterization. Two uninucleate rhizoctonia fungi, obtained from Oncidium barbaceniae, and two phytopathogenic isolates were included as outgroups. Qualitative and quantitative morphological characteristics were analyzed using multivariate statistics and were able to distinguish Ceratobasidium, Tulasnella and Thanatephorus genera and separate the isolates of Tulasnella spp. into two groups. Analysis of RAPD (Random Amplified Polymorphic DNA) and ITS rDNA sequences validated the morphological data. Symbionts of O. barbaceniae presented identity to ITS sequences of Ceratobasidium genus, while E. secundum isolates presented identity to two species of Tulasnella. We observed homogeneity among Tulasnella spp. obtained from a single population and from neighboring populations, but there was higher variability among isolates obtained from populations of regions that were farther apart. Morphological data associated with multivariate statistics proved to be a useful tool in the multi-level taxonomy of these orchid-associated fungi and in estimating the diversity of orchid mycorrhizal fungi.  相似文献   

18.
19.
Length–weight relationships for Alburnus arborella, Esox cisalpinus and Scardinius hesperidicus from Trasimeno Lake are provided. A total of 4,205 specimens were collected for examination from 2008 to 2014 throughout the lake by means of electrofishing and nets. For all species the value of b ranged from 2.887 for Esox cisalpinus males to 3.115 for Scardinius hesperidicus. The study provides the first reference of length–weight relationships for the three species. A new maximum total length is also reported for E. cisalpinus.  相似文献   

20.
Individuals of jacks that were captured off the Rio de Janeiro coast were characterized using multivariate morphometrics and allozymes molecular markers. The main objectives were to determine the number of fish captured and their species. Classical taxonomic classification and multivariate morphometry indicated the existence of three species in the landings from Rio de Janeiro State (Caranx crysos, Carangoides bartholomaei and Caranx latus). The results of the genetic analyses performed were consistent with these results. However, Bayesian analysis revealed the possible presence of a fourth species, which could not be discriminated by classical taxonomy. Caranx crysos possibly comprises two different species. Other population indexes, such as unique alleles, degree of structuring and genetic identity, also pointed to different species. Therefore, based on evidences from classical taxonomy, geometric morphometric analyses together with genetic data from allozymes molecular markers it is possible to support that at least four different Carangidae species are present in fish landings from Niterói, Rio de Janeiro State, Brazil, whereas fish capture records for the same location have recorded only two species. These results are important for not only developing fisheries management strategies but also providing general information regarding the ecology and evolution of the genus.  相似文献   

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