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1.
The population of pond smelt Hypomesus olidus has been registered for the first time in the water bodies of Bering Island (Commander Islands). The spawning of this species has been observed in the Sarannoe Lake system, and the maturing breeders have been caught in the freshwater-brackish Gavanskoe Lake system. The spawning grounds, the spawning period, the environment, and the morphology of the breeders have been described. The ratio of Ca and Sr isotopes in the otoliths of the pond smelt inhabiting the Sarannoe Lake system evidenced that this species here was presented by the resident ecotype. The problem of the smelt phylogeny and resettlement in the northern Pacific Ocean is discussed.  相似文献   

2.
Nucleotide sequences of the mitochondrial DNA cytochrome b (CytB) gene fragment and the control region (D-loop) of Dolly Varden (Salvelinus malma) from the Commander Islands and the Kol River of the Kamchatka Peninsula were examined. A high level of genetic variability of island populations comparable to that of the mainland population of western Kamchatka was demonstrated. The belonging of the Commander Islands chars to the genetic lineage of northern Dolly Varden Salvelinus malma malma was confirmed.  相似文献   

3.
Habrobracon hebetor Say (Hymenoptera: Braconidae) is a cosmopolitan gregarious ectoparasitoid that attacks larvae of several species of Lepidoptera. Although there are two genetically different strains within H. hebetor, distribution of the strains has been poorly understood. In 2010, in Thailand, where H. hebetor has been known as a parasitoid of stored grain pests, it was found that H. hebetor attacked Opisina arenosella Walker (Lepidoptera: Oecophoridae), which is an invasive pest of coconut palm. For correct identification of this H. hebetor, we conducted DNA analysis and cross tests using populations collected from O. arenosella and stored grain pests in Thailand and populations in Japan known as H. hebetor. We obtained 413 bp of mitochondrial cytochrome oxidase I (COI) sequences and 414 bp of 16S rRNA gene sequences, and both indicated that there are two distinct clades within H. hebetor: one contains insects from Thailand, Spain, India, and Barbados; the other contains insects from Japan and the USA. There were no genetic differences or sexual isolation between Thai populations from different hosts. Our results also showed that populations in Thailand were sexually isolated from a H. hebetor population in Japan.  相似文献   

4.
Pelagic larval dispersal habits influence the population genetic structure of marine mollusk organisms via gene flow. The genetic information of the clam Gomphina aequilatera (short larval stage, 10 days) which is ecologically and economically important in the China coast is unknown. To determine the influence of planktonic larval duration on the genetic structure of G. aequilatera. Mitochondrial markers, cytochrome oxidase subunit i (COI) and 12S ribosomal RNA (12S rRNA), were used to investigate the population structure of wild G. aequilatera specimens from four China Sea coastal locations (Zhoushan, Nanji Island, Zhangpu and Beihai). Partial COI (685 bp) and 12S rRNA (350 bp) sequences were determined. High level and significant FST values were obtained among the different localities, based on either COI (FST?=?0.100–0.444, P?<?0.05) or 12S rRNA (FST?=?0.193–0.742, P?<?0.05), indicating a high degree of genetic differentiation among the populations. The pairwise Nm between Beihai and Zhoushan for COI was 0.626 and the other four pairwise Nm values were >?1, indicating extensive gene flow among them. The 12S rRNA showed the same pattern. AMOVA test results for COI and 12S rRNA indicated major genetic variation within the populations: 77.96% within and 22.04% among the populations for COI, 55.73% within and 44.27% among the populations for 12S rRNA. A median-joining network suggested obvious genetic differentiation between the Zhoushan and Beihai populations. This study revealed the extant population genetic structure of G. aequilatera and showed a strong population structure in a species with a short planktonic larval stage.  相似文献   

5.
Fauchea guiryi Selivanova sp. n. (Rhodymeniales, Faucheaceae) from the Commander Islands (Russian Pacific coast) is described and illustrated. The new species is compared with closely related taxa of the family Faucheaceae and the genus Fauchea, among them those from the Pacific coast of North America.  相似文献   

6.
Two smelt species that inhabit the northwest of the Sea of Japan, Hypomesus japonicus and H. nipponensis (family Osmeridae), which are both currently referred to as Japanese smelt, have been studied in order to clarify the taxonomic value of morphometric characters. Variations between individuals of these species have been revealed using a multivariate analysis of their morphometric characters and indices. The results of the analysis show that H. japonicus is distinguished from H. nipponensis both by the previously known characters (the eye diameter is smaller and the vertical through the beginning of the dorsal fin is closer to the head than that through the beginning of the pelvic fins) and by a greater height of the dorsal and adipose fins in the former species as defined in the paper. Within the species H. japonicus, the individuals sampled from Olga Bay are most similar morphologically to those from the coastal waters off the village of Terney. In contrast, the individuals of this species from the coastal waters off Russky Island and from Olga Bay manifest the greatest differences.  相似文献   

7.
A critical analysis of literature data on the distribution, morphology, and phylogeography of the Arctic lamprey (Lethenteron camtschaticum) and five species of marine and anadromous fish such as navaga (Eleginus navaga), pollock (Theragra chalcogramma), rainbow smelt (Osmerus mordax dentex), Pacific herring (Clupea pallasii), and pond smelt (Hypomesus olidus) has been performed. The results show that all these species have colonized Northern European seas, distributing along the Arctic coastline of Eurasia after the glacier retreat. The reasons that the dispersal of these species in the Atlantic Ocean may be impeded (preference for a cold environment, competition, and decrease of the evolutionary potential) are discussed.  相似文献   

8.
9.
The freshwater pearl mussel Margaritifera margaritifera L. is one of the most endangered freshwater mussels in the world. Effective conservation of threatened species requires not only ecological, but also genetic information from the target species and populations. Since low genetic diversity can reduce the ability of a species to adapt to environmental changes, maintaining genetic diversity has been identified as one of the key elements in successful conservation programs. We examined genetic variation of the freshwater pearl mussel from the River Vuokkijoki, Karelia, Russia. We sequenced a fragment of the cytochrome c oxidase subunit I gene (COI) from 22 individuals and compared the data to 32 previously published COI sequences available in GenBank. We identified 10 different COI haplotypes in the sequenced samples, three of which had not been previously reported. Our results show that the River Vuokkijoki has high genetic diversity and suggest that the colonization of this northern freshwater pearl mussel population might have occurred from multiple and even distant refugia. Therefore, the freshwater pearl mussel population of the River Vuokkijoki is valuable for the conservation of the whole species.  相似文献   

10.
Ranges of different species of medicinal leeches (Hirudo spp.) are nearly mutually exclusive with very few areas of overlapping. This biogeographical pattern suggests different ecological requirements for the two species. However, two habitats in Hungary and Ukraine where populations of H. verbana and H. medicinalis coexist were found. The aim of this research was to reveal differences in size structures and phenologies between the two species in a steppe pond with two populations. The study was conducted from March to September in 2009 and 2010 in Horila Dolyna, Kharkiv Region. Leeches were collected several times during the season, weighed and released. The abundance of H. verbana was always higher. The Mann-Whitney U-test and the Wilcoxon test were applied. Significant differences between sequential samples within the species were found. The large weight classes of H. verbana emerged by the end of summer and caused a higher variance in contrast to H. medicinalis. This suggests the higher growth rate and the more r-strategic biology of H. verbana in comparison with the largely K-strategic H. medicinalis.  相似文献   

11.
The frequency of occurrence of the COI gene of mitochondrial DNA in the Pacific flatnose Antimora microlepis and blue antimora Antimora rostrata (Moridae, Gadiformes) was analyzed in samples collected in different areas of the World Ocean. The revealed maximum haplotype diversity of COI in the blue antimora in the North Atlantics may indicate that this species emerged in this region, from which it widely distributed in the World Ocean. The Pacific flatnose Antimora microlepis originated from Antimora rostrata. Antimora might penetrate into the North Pacific by several routes: through the Panama Strait, along the coast of Antarctica, or through the Indian Ocean along the coast of Australia.  相似文献   

12.
Ting Ma  Jia Huang 《Biologia》2018,73(12):1205-1213
A new species of the genus Morellia Robineau-Desvoidy, 1830, Morellia (Morellia) trifurcata sp. n., collected from Yunnan, China is described. Four DNA sequences of the partial mitochondrial cytochrome c oxidase subunit I (mtCOI) gene of this new species are provided. In order to evaluate the availability of DNA barcoding for identifying Morellia species, 38 currently available, non-identical COI sequences of 16 Morellia species are involved in a molecular analysis using the neighbor-joining (NJ) method. The intra- and interspecific p-distances are summarized.  相似文献   

13.
Morphological variability of four characters in 13 samples of pond smelt Hypomesus olidus is investigated using three parameters: fluctuating asymmetry, geographic variability, and variability of characters. The differences in the level of fluctuating asymmetry in H. olidus from various water bodies of the Far East and, thus, in the stability of development depend on the differences in conditions of embryonic and early postembryonic development. Only one character of four (mean number of soft rays in pectoral fins) shows presence of geographic variability in smelt: the mean value of this character increase from north to south. Estimation of variability of characters demonstrates that the maximum fluctuations of the variation coefficient are characteristic of the number of infraorbital bones and the minimal fluctuations are characteristic of the number of soft rays in pectoral fins.  相似文献   

14.
The aim of this study was to investigate whether Pleistocene climatic instability influenced the phylogeographic structure and historical demography of an endemic Atlantic Forest (AF) orchid bee, Euglossa iopoecila Dressler, which shows two main patterns of integument colors over of its geographical distribution. We based our analysis on the concatenated sequence of four mtDNA segments belonging to genes 16S (357 bp), Cytb (651 bp) and COI (1206 bp), totaling 2234 bp. Samples of E. iopoecila populations were collected in 14 AF remnants along its geographic distribution. Median-Joining haplotype networks, SAMOVA and BAPS results indicated three lineages (southern, central and northern clusters) for E. iopoecila, with two important phylogeographic ruptures. We found higher genetic diversity among samples collected in the central region of the AF, which coincides with predicted areas of climatic stability, according to recent AF stability–extinction model. The demographic analysis suggests that only the southern cluster had undergone recent population expansion, which probably started after the last glacial maximum (LGM). Our data suggest that the differentiation observed in the three mitochondrial lineages of E. iopoecila is the result of past disconnections and multiple extinction/recolonization events involving climate fluctuations. In terms of conservation, we would emphasize the importance of considering: (1) the region of the central clade as the location of the highest genetic diversity of mtDNA of E. iopoecila populations; (2) the philopatric behavior of females that tends to restrict mtDNA gene flow in particular, with direct implications for the conservation of the total genetic diversity in euglossine populations.  相似文献   

15.
The pregnancy-associated glycoprotein-like family (PAG-L) is a large group of chorionic products, expressed in the pre-placental trophoblast and later in the post-implantational chorionic epithelium, and are involved in proper placenta development and embryo-maternal interaction in eutherians. This study describes identification of the PAG-L family in the genome of the Eurasian beaver (Castor fiber L.), named CfPAG-L. We identified 7657 bp of the CfPAG-L gDNA sequence (Acc. No. KX377932), encompassing nine exons (1–9) and eight introns (A–H). The length of the CfPAG-L exons (59–200 bp) was equivalently similar to the only known counterparts of bPAG1, bPAG2, and pPAG2. The length of the CfPAG-L introns ranged 288–1937 bp and was completely different from previously known PAG introns. The exonic CfPAG-L regions revealed 50.3–72.9% homology with equivalent segments of bPAG1 and pPAG2 structure. The intronic CfPAG-L regions alignments revealed a lack of homology. Within the entire CfPAG-L gene, 31 potential single nucleotide variants (SNV: 7 transversions and 24 transitions) were predicted. The identified exonic polymorphic loci did not affect the amino acid sequence of the CfPAG-L polypeptide precursor. This is the first report describing the CfPAG-L gene sequence, structural organization, and SNVs in the Eurasian beaver, one of the largest rodents.  相似文献   

16.
Hyphantria cunea (Drury) has colonized many countries outside its native range of North America and has become a model species for studies of the colonization and subsequent adaptation of agricultural pests. Molecular genetic analyses can clarify the origin and subsequent adaptations to non-native habitats. Using the mitochondrial COI gene, we examined the genetic relationships between invasive populations (China, Iran, Japan, and Korea) and native populations (i.e., the United States). The Jilin (China) and Guilan (Iran) populations showed nine previously unknown haplotypes that differed from those found in the south–central United States, suggesting multiple colonization events and different regions of invasion. A dominant mtDNA haplotype in populations in the United States was shared by all of the populations investigated, suggesting that H. cunea with that haplotype have successfully colonized China, Iran, Japan, and Korea.  相似文献   

17.
The conservation of narrow endemic species relies on accurate information regarding their population structure. Juglans hopeiensis Hu (Ma walnut), found only in Hebei province, Beijing, and Tianjin, China, is a threatened tree species valued commercially for its nut and wood. Sequences of two maternally inherited mitochondrial markers and two maternally inherited chloroplast intergenic spacers, three nuclear DNA sequences, and allele sizes from 11 microsatellites were obtained from 108 individuals of J. hopeiensis, Juglans regia, and Juglans mandshurica. Haplotype networks were constructed using NETWORK. Genetic diversity, population differentiation, and analysis of molecular variance (AMOVA) were used to determine genetic structure. MEGA was used to construct phylogenetic trees. Genetic diversity of J. hopeiensis was moderate based on nuclear DNA, but low based on uniparentally inherited mitochondrial DNA and chloroplast DNA. Haplotype networks showed that J. hopeiensis haplotypes were different than haplotypes found in J. regia and J. mandshurica. Allelic variants in nuclear genes that were shared among J. hopeiensis populations were not found in J. regia or J. mandshurica. Sampled populations of J. hopeiensis showed clear genetic structure. The maximum parsimony (MP) tree showed J. hopeiensis to be distinct from J. mandshurica but threatened by hybridization with J. regia and J. mandshurica. J. hopeiensis populations are strongly differentiated from sympatric Juglans species, but they are threatened by small population sizes and hybridization.  相似文献   

18.
Combined morphological and molecular analyses are used to characterise two new species of Haplorchoides Chen, 1949 (Digenea: Heterophyidae) from an Australian siluriform fish. Haplorchoides maiwariensis n. sp. and H. daguilarensis n. sp. are described from the intestine of the Blue salmon catfish, Neoarius graeffei (Kner & Steindachner) (Siluriformes: Ariidae) from tidal reaches of the Brisbane River and from a freshwater creek off Lake Wivenhoe, Kipper Creek, Australia. The two new species most obviously differ from all previously described species of Haplorchoides in possessing clearly and reliably tripartite seminal vesicles. The two new species differ in the size and distribution of vitelline follicles, the size of the pigment granules and the form of the ventral sucker. Previously described species of Haplorchoides have been reported from Africa and Asia, principally from bagrid, schilbeid, silurid and sisorid catfishes; these are the first species reported from an ariid catfish. Complete ITS2 and partial 28S ribosomal DNA data were generated for both new species. The two species differ from each other by eight base pairs in the ITS2 region, and by 13 bp for the 28S region. The 28S rDNA sequence of H. daguilarensis agrees with a previously reported sequence from an unidentified species of Haplorchoides collected from N. graeffei in Lake Wivenhoe, Australia; we identify this previous report as relating to H. daguilarensis.  相似文献   

19.
Mitochondrial genome fragments were examined in all species of the genus Capra (Bovidae, Artiodactyla). Phylogenetic analysis was carried out using 59 cytochrome b gene sequences (392 bp), and 22 sequences of the mtDNA variable fragment (402 bp). In the control region, two unique deletions were revealed. One of the deletions was found only in Capra cylindricornis (17 bp), while another one grouped C. caucasica with C. aegagrus (1 bp). The group of Caucasian wild goats splits into two clades, and furthermore, the sequences of C. caucasica demonstrate remarkable similarity to the sequences of C. aegagrus, while C. cylindricornis seems to have evolved independently for a long period of time. It was demonstrated that C. pyrenaica and C. ibex were extremely close to one another. Capra sibirica formed an outer group relative to the other species, and according to our data, was the most ancient species of the genus. On the contrary, genetic distance separating C. falconeri (the most independent species of the genus related to its morphology) from the other species is small.  相似文献   

20.
The genetic analysis is made on the population of the European smelt Osmerus eperlanus occasionally introduced to Lake Syamozero (Karelia) and of the vendace Coregous albula supposedly acclimatized in Solovetskie Islands as a result of fish cultural activities of the Solovetskii Monastery. They are compared with several natural populations—possible donors for both introductions. Genetic variation in a sample of smelt was estimated by means of restrictase analysis of mtDNA (fragment ND1/ND2) in samples of vendace—by means of allozyme analysis of six isoenzyme systems. The probable population for the Syamozero smelt is the population of Onega Lake in spite of the previously noted greater morphological similarity of colonizers with the smelt of Ladoga Lake. A high level of genetic variation in the Syamozero smelt in comparison with native populations indicates that, beside the introduction from Onega Lake, there were repeated introductions from neighboring water bodies. The genetic analysis of the Solovetskaya vendace does not prove that the vendace appeared on islands due to acclimatization. Frequencies of alleles of allozyme loci in the Solovetskaya population significantly differ from frequencies in continental populations. Still, it is compared with some populations of the Arkhangelsk oblast. Estimations of genetic diversity of the Solovetskaya vendace turned out to be comparable with those in native populations.  相似文献   

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