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1.
The morphology and intraspecific structure of Triplophysa orientalis inhabiting the inland basins of Tsaidam (northeastern edge of the Tibetan Plateau) and the basin of the upper reach of the Huang He River in China were studied. Significant morphological differences between the populations from the inland basins and the Huang He River were revealed; the latter were distinguished as a separate subspecies T. o. hwanghoensis subsp. n. Intermediate character of some traits of the new subspecies between the nominative subspecies and T. hutjertjuensis was found; as a result, the status of the latter was reduced to the subspecies level. The synonymy of T. o. elongata with the nominative subspecies was confirmed. The differences between T. orientalis and T. obscura—morphologically poorly distinguishable species, sympatric in the basin of the upper reach of the Huang He River—were defined more exactly.  相似文献   

2.
The geographic distribution of the populations of a species are influenced by the spatial structure of the ecosystems, the environmental factors and the presence of geographic barriers. The Neotropical otter, Lontra longicaudis, is widely distributed throughout the Americas, where a wide range of environmental conditions and geographical features could promote genetic and morphological variation on the three currently recognized subspecies. In this study, we combined phylogeographic, morphometric and environmental niche modelling analyses to examine whether: (1) genetic variation is associated with the presence of barriers to gene flow and/or hydrography; (2) genetic and morphologic variation are associated with environmental variation; and (3) the observed variation in L. longicaudis populations corresponds to the previously defined subspecies. We found strong phylogeographic structure between the northern (L. l. annectens) and the two-southern subspecies (L. l. longicaudis and L. l. enudris), and although shallower, we also detected genetic differentiation between the two South American subspecies. Such genetic differentiation corresponds to the hydrography and to the geographical barriers characteristic of the distributional area of the species. We found a correlation between the shape of the skull and mandible with the environmental variation through the distribution of the species, and we rejected the hypothesis of niche equivalency and similarity between the three identified genetic lineages, suggesting adaptations to different environmental conditions. Our results support that the variation in environmental conditions, in concert with geographical barriers to gene flow and hydrography, have led to population divergence of L. longicaudis along the Neotropics. These results have important taxonomic implications for the species and its conservation.  相似文献   

3.
The degree of development of the mechanisms of postcopulatory isolation was evaluated on the basis of experimental hybridization of representatives of three subspecies of M. musculus (M. m. musculus, M. m. wagneri, and M. m. gansuensis) and remote populations of the subspecies M. m. musculus. Experimental crosses between the different subspecies and populations indicated the presence of initial stages of postcopulatory reproductive isolation between some forms of house mice. In a number of crosses conducted between different populations and subspecies of M. musculus, asymmetry was observed. In one variant of mating, M. m. musculus (male) × M. m. wagneri (female), a reduced intensity of breeding and nonviability of pups were observed. A decrease in the intensity of reproduction was found in all variants of crosses that used male M. m. musculus from the city of Ishim. These data are assumed to confirm the previous assumption about the hybrid origin of mice inhabiting that city. The results confirm a significant level of divergence of the subspecies M. m. musculus and M. m. wagneri. Thus, initial stages both of post- and precopulatory isolation mechanisms between M. m. wagneri and M. m. musculus were shown.  相似文献   

4.
A list of species of the staphylinid subfamily Euasthetinae from the Baikal Area and adjacent territories is given. Edaphus beszedesi Rtt. and Euasthetus mandschuricus Puthz are new records for Russia, Eu. superlatus Peyer., for Siberia, Eu. laeviusculus Mnnh., for the Baikal Area, and Eu. ruficapillus Lac., for western Siberia. [Records of Eu. bipunctatus and Eu. ruficapillus from “Kamenesch-Podolsk” in the original Russian text actually refer to the misspelled City of Kamenets-Podolskii in Western Ukraine and, thus, the records of these two species for Western Siberia are erroneous.—Ed.]  相似文献   

5.
Analysis of the control region of mitochondrial DNA (mtDNA) or D-loop of 96 house mice (Mus musculus) from Russia, Moldova, Armenia, Azerbaijan, Kazakhstan, and Turkmenistan has been used to reconstruct the phylogenetic relationships and phylogeographic patterns of intraspecific forms. New data on the phylogenetic structure of the house mouse are presented. Three phylogroups can be reliably distinguished in the eastern part of the M. musculus species range, the first one mainly comprising the haplotypes of mice from Transcaucasia (Armenia); the second one, the haplotypes of mice from Kazakhstan; and the third one, the haplotypes of mice from Siberia and some other regions. The morphological subspecies M. m. wagneri and M. m. gansuensis have proved to be genetically heterogeneous and did not form discrete phylogroups in the phylogenetic tree.  相似文献   

6.
Restriction enzyme analysis of the mitochondrial DNA (mtDNA) fragment encoding subunit 1 of the NADH dehydrogenase complex (ND-1) amplified via polymerase chain reaction (PCR) has been used to obtain data on genetic differentiation of muksun Coregonus muksun (Pallas) populations. Population polymorphism with respect to the restriction sites of 18 endonucleases has been described. It has been demonstrated that the muksun is genetically related to the pidschian C. pidschian (Gmelin), its sympatric species in Siberian waters. Analysis of the median network of mtDNA haplotypes has shown that haplotypes of muksun from various Siberian basins form a common group with haplotypes of pidschian of the Arctic Ocean basin, some frequent haplotypes been found in both forms. This raises the question as to the validity of the muksun as a species. Differences within this group of haplotypes are much smaller than those typical of species of the genus Coregonus. The possibility of a hybrid origin of the muksun from a pidschian-like ancestor and species of the cisco-peled (C. sardinella-C. peled) complex is discussed.  相似文献   

7.
Numerous termite species have been introduced outside their native ranges by human transport, and some have become invasive. The dampwood termite Zootermopsis nevadensis (Hagen), which is native to western North America, has been introduced to and become established in Kawanishi City, Hyogo Prefecture, Japan. Zootermopsis nevadensis is subdivided into two subspecies based on cuticular hydrocarbon (CHC) phenotypes: Znevadensis nevadensis and Znevadensis nuttingi (Haverty and Thorne). Here, we identified Znevadensis in Japan as hybrids between the two subspecies. Chemical analysis showed the presence of 7,15-dimethylhenicosane and 5,17-dimethylhenicosane in the CHCs of Znevadensis in Japan, corresponding to the CHC phenotype of Znnevadensis. Conversely, all mitochondrial cytochrome c oxidase subunit I sequences of Znevadensis in Japan were identical to sequences from Znnuttingi and hybrids between the two subspecies from a native hybrid zone in California, USA. In addition, phylogenetic analysis showed that Znevadensis in Japan formed a clade with Znnuttingi and hybrids between the two subspecies. Our results show discordance between the chemical and genetic features of Znevadensis in Japan, indicating that individuals of Znevadensis in Japan are hybrids between the two subspecies.  相似文献   

8.
A multivariate analysis of 11 skull measurements, along with evaluation of the shape of maxill-premaxill suture at palatine foramina, was carried out in pikas of thealpina-hyperborea group. The study provided rational for recognition of three distinct species in this group:Ochotona alpina (Pallas, 1773),O. hyperborea (Pallas, 1811), andO. turuchanensis Naumov, 1934.O. turuchanensis is a species from central Siberia differing fromO. hyperborea in the chromosome number and type of palatine foramina and fromO. alpina in size of the skull. This species is allopatric withO. alpina and partly sympatric withO. hyperborea. The subspeciessvatoshi is reportedly allocated toO. hyperborea. The taxonomic status ofmantchurica (now allocated tohyperborea) and scorodumovi (treated at present as an isolated subspecies of O. alpina) needs careful investigation.  相似文献   

9.
Eight pairs of chloroplast DNA (cpDNA) universal primers selected from 34 pairs were used to assess the genetic diversity of 132 pear accessions in Northern China. Among them, six amplified cpDNA fragments showed genetic diversity. A total of 24 variable sites, including 1 singleton variable site and 23 parsimony informative sites, as well as 21 insertion-deletion fragments, were obtained from the combined cpDNA sequences (5309–5535 bp). Two trnL-trnF-487 haplotypes, five trnL-trnF-413 haplotypes, five rbcL haplotypes, six trnS-psbC haplotypes, eight accD-psaI haplotypes and 12 rps16-trnQ haplotypes were identified among the individuals. Twenty-one haplotypes were identified based on the combined fragments. The values of nucleotide diversity (Pi), average number of nucleotide differences (k) and haplotype diversity (Hd) were 0.00070, 3.56408 and 0.7960, respectively. No statistical significance was detected in Tajima’s D test. Remarkably, the important cpDNA haplotypes and their representing accessions were identified clearly in this study. H_19 was considered as one of the ancient haplotypes and was a divergent centre. H_16 was the most common haplotype of the wild accessions. H_2 was the haplotype representing the most pear germplasm resources (46 cultivars and two wild Ussurian Pear accessions), followed by haplotype H_5 (30 cultivars, two wild Ussurian Pear accessions and four sand pears in outgroups) representing the cultivars ‘Dangshan Suli’ and ‘Yali’, which harbour the largest and the second largest cultivation areas in China. More importantly, this study demonstrated, for the first time, the supposed evolution routes of Pyrus based on cpDNA divergence in the background of pear phylogeny in Northern China.  相似文献   

10.
The burbot (Lota lota L.) is a northern freshwater fish with a circumpolar distribution. Two subspecies diverged due to isolation during glacial maxima: Lota lota lota is the Eurasian-Beringian subspecies and Lota lota maculosa the North American subspecies. We sampled burbot from the Great Slave Lake and Mackenzie River area, Canada, the only known contact zone of these two lineages. Using molecular methods (microsatellite loci and mtDNA sequence) we found that the subspecies’ distributions abut in the Mackenzie River delta, with L. l. lota in the lower delta and L. l. maculosa in all upstream rivers and lakes. Admixture between subspecies was minimal, decreased with increasing geographic distance, and was asymmetrical: mitochondrial and nuclear genetic introgression was from L. l. lota into L. l. maculosa but not the reverse. Within subspecies, there was low inter-population genetic differentiation, no isolation-by-distance, and no evidence for sex-biased dispersal. We did not identify a difference in body length between subspecies per se, though mean lengths differed among localities. Thus, genetic data demonstrate that burbot subspecies are reproductively isolated though the extent to which morphologically variability relates to local versus subspecific variation remains unclear.  相似文献   

11.
First evidence for the presence of copies of mitochondrial cytochrome b gene of the subspecies group Luscinia calliope anadyrensis–L. c. camtschatkensis in the nuclear genome of nominative L. c. calliope was obtained, which indirectly indicates the nuclear origin of the subspecies-specific mitochondrial haplotypes in Siberian rubythroat. This fact clarifies the appearance of mitochondrial haplotypes of eastern subspecies by exchange between the homologous regions of the nuclear and mitochondrial genomes followed by fixation by the founder effect. This is the first study to propose a mechanism of DNA fragment exchange between the nucleus and mitochondria (intergenomic recombination) and to show the role of nuclear copies of mtDNA as a source of new taxon-specific mitochondrial haplotypes, which implies their involvement in the microevolutionary processes and morphogenesis.  相似文献   

12.

Background

The roe deer, Capreolus sp., is one of the most widespread meso-mammals of Palearctic distribution, and includes two species, the European roe deer, C. capreolus inhabiting mainly Europe, and the Siberian roe deer, C. pygargus, distributed throughout continental Asia. Although there are a number of genetic studies concerning European roe deer, the Siberian roe deer has been studied less, and none of these studies use microsatellite markers. Natural processes have led to genetic structuring in wild populations. To understand how these factors have affected genetic structure and connectivity of Siberian roe deer, we investigated variability at 12 microsatellite loci for Siberian roe deer from ten localities in Asia.

Results

Moderate levels of genetic diversity (H E = 0.522 to 0.628) were found in all populations except in Jeju Island, South Korea, where the diversity was lowest?(H E?= 0.386). Western populations showed relatively low genetic diversity and higher degrees of genetic differentiation compared with eastern populations (mean Ar = 3.54 (east), 2.81 (west), mean F ST = 0.122). Bayesian-based clustering analysis revealed the existence of three genetically distinct groups (clusters) for Siberian roe deer, which comprise of the Southeastern group (Mainland Korea, Russian Far East, Trans-Baikal region and Northern part of Mongolia), Northwestern group (Western Siberia and Ural in Russia) and Jeju Island population. Genetic analyses including AMOVA (F RT = 0.200), Barrier and PCA also supported genetic differentiation among regions separated primarily by major mountain ridges, suggesting that mountains played a role in the genetic differentiation of Siberian roe deer. On the other hand, genetic evidence also suggests an ongoing migration that may facilitate genetic admixture at the border areas between two groups.

Conclusions

Our results reveal an apparent pattern of genetic differentiation among populations inhabiting Asia, showing moderate levels of genetic diversity with an east-west gradient. The results suggest at least three distinct management units of roe deer in continental Asia, although genetic admixture is evident in some border areas. The insights obtained from this study shed light on management of Siberian roe deer in Asia and may be applied in conservation of local populations of Siberian roe deer.
  相似文献   

13.
The results of analysis of the frequencies of t-alleles and heterozygous +/t individuals of house mice of different subspecies (musculus, bactrianus, tataricus, wagneri, and gansuensis) are presented for the natural populations inhabiting eight cities and five regions of Russia and adjacent countries of Eastern Europe and Asia. It is shown that the frequencies of t-alleles are 0.18 ± 0.03 in small samples (1–30 individuals) and 0.09 ± 0.06 in medium-sized samples (31–60 individuals). The factors that reduce the frequencies of t-alleles in natural populations and the mechanisms that prevent invasion and fixation of t-mutant alleles in the Mus musculus genome are discussed.  相似文献   

14.
Information on some ecological features of eight species of pond snails belonging to the subgenera Peregriana and Radix (Lymnaea ampla (Hartmann), L. ampullacea (Rossmässler), L. auricularia (L.), L. balthica (L.), L. fontinalis (Studer), L. lagotis (Schrank), L. ovata (Draparnaud), and L. tumida (Held)) in the waterbodies of south of Western Siberia is presented. The patterns of the species distribution and their cooccurrence in different waterbodies have been studied. An analysis of the quantitative variables (abundance and biomass) of the snails in the waterbodies of the Karasuk lake-river system and in the Novosibirsk Reservoir has been performed.  相似文献   

15.
We carried out an allozyme analysis to investigate polymorphism and genetic structure of the populations of D. incarnata and D. ochroleuca in regions of their joint growth in Russia and Belarus. We found that D. ochroleuca individuals in the populations of the Urals and Siberia, which are distant fragments from the main range of the species, do not differ significantly from individuals within the main part of the area (Belarus) on the basis of the allelic composition of eight gene loci. We revealed that D. ochroleuca and D. incarnata are differentiated by different alleles of the GDH locus. Thus, we established a genetic marker suitable to distinguish these closely related taxa. In addition to the GDH locus, D. ochroleuca and D. incarnata in the places of their joint growth, differ in the allelic structure of the PGI and NADHD loci. D. incarnata from the Urals and Siberia were polymorphic for both loci, and individuals from Belarus were polymorphic for one locus (PGI). In contrast, all D. ochroleuca individuals growing in sympatric populations with polymorphic D. incarnata were homozygous for the same alleles. Thus, comparison of the genetic structure of D. ochroleuca and D. incarnata points to the existence of a genetic isolation and a functioning isolation mechanism even under conditions of their joint growth. We found that the GDH locus in D. incarnata is polymorphic only in populations which grow together with D. ochroleuca, with exception a few examples. Thus, we conclude that variability of the GDH locus in D. incarnata is associated with hybridization with D. ochroleuca.  相似文献   

16.
The genus Zungaro contains some of the largest catfish in South America. Two valid species are currently recognized: Zungaro jahu, inhabiting the Paraná and Paraguay basins, and Zungaro zungaro, occurring in the Amazonas and Orinoco basins. Analysing Zungaro specimens from the Amazonas, Orinoco, Paraguay and Paraná basins, based on the sequencing of COI and D-loop, we found at least three MOTUs, indicating the existence of hidden diversity within this fish group. Considering the ecological and economic values of this fish, our results are surely welcomed for its conservation, disclosing new findings on its diversity and pointing out the necessity for a detailed taxonomic revision.  相似文献   

17.
Sequence polymorphism of the mitochondrial DNA cytochrome b gene fragment was analyzed in 21 specimens of subspecies Luscinia calliope calliope (Pallas, 1776) and two specimens of L. c. anadyrensis (Portenko, 1939). On sequence chromatograms, in 19 specimens of L. c. calliope, double peaks of heteroplasmy type in the taxon-specific positions were revealed. Moreover, two clone variants were identified. The first variant was the calliope mitochondrial cyt b gene and the second was the nuclear cyt b pseudogene, similar to the mitochondrial haplotype anadyrensis-camtschatkensis. In L. c. anadyrensis, four clone variants, represented by the mitochondrial calliope and anadyrensis-camtschatkensis cyt b genes and nuclear calliope and sachalinensis cyt b pseudogenes, were identified. Some nuclear cyt b pseudogenes were highly similar (98–99%) to the mitochondrial genes of the subspecies L. c. anadyrensis, L. c. camtschatkensis, and L. c. sachalinensis. In the same time, the majority of nuclear pseudogene sequences were characterized by a high level of polymorphism, caused by nonsynonymous substitutions (up to five substitutions per sequence), the presence of indels in some of the clones, and TAA and TGA stop codons. In our opinion, the mitochondrial haplotypes anadyrensis-camtschatkensis and sachalinensis occurred as a result of intergenomic homologous recombination. This finding provides a new insight into the colonization history of the northeastern part of the range by L. calliope, according to which populating the territory of Chukotka, Kamchatka, and Sakhalin took place at different times and along the independent pathways.  相似文献   

18.
The faunal composition of Diptera (Insecta) inhabiting the galleries of Polygraphus proximus over the territory of Siberia and the Russian Far East was studied. As a result, 14 species of Diptera were discovered representing 8 families. Within its secondary range, the invasive beetle P. proximus Blandford, 1894 is affected not only by the well-known introduced species Medetera penicillata Negrobov, 1970 but also by numerous other widespread predatory flies, such as Medetera excellens Frey, 1909, M. pinicola Kowarz, 1877, Xylophagus cinctus (De Geer, 1776), and Toxoneura ephippium (Zettersted, 1860). Four predatory fly species, M. penicillata, M. signaticornis Loew, 1857, Lonchaea bukowskii Czerny, 1934, and Xylophagus sachalinensis (Pleske, 1925), affect P. proximus within its native range in the Russian Far East. Data on the predation of each species of Diptera on several species of bark beetles testify to their polyphagy. Saprophagous larvae of Dicranomyia modesta (Meigen, 1818), Chalcosyrphus piger (Fabricius, 1794), Xylosciara lignicola (Winnertz, 1867), and Pseudolycoriella unispina (Mohrig et Krivosheina, 1983) were discovered in bark beetle galleries for the first time.  相似文献   

19.
Allozyme variation of a rare relict plant, birthwort Aristolochia manshuriensis Kom., was examined. The main parameters of genetic variation in natural populations of A. manshuriensis from the Anan’evka, Nezhinka, and Malaya Borisovka river basins (Primorskii Krai) were inferred from analysis of nine enzyme systems, presumably encoded by 18 loci. At 99% polymorphism criterion, 24.4% of A. manshuriensis loci were shown to be polymorphic. The mean number of alleles per locus was 1.24; the mean observed and expected heterozygosities, 0.12 and 0.10, respectively.  相似文献   

20.
This paper studies the phylogeography of Alnus alnobetula s. l. in the Asian part of the Russian range with the use of chloroplast DNA (cpDNA) sequences (intergenic spacers trnH-psbA, trnS-trnG, and psaA-trnS). Nine haplotypes were identified as a result of a combination of polymorphism of all sites in 241 plants in 20 populations of A. alnobetula. High interpopulation differentiation (GST = 0.914, NST = 0.928) and a significant phylogeographic structure (NST > GST, p < 0.05) were found. Reconstruction of genealogical relationships of green alder haplotypes revealed five highly divergent genetic lineages: one geographically widespread throughout Siberia and the Urals and several allopatric lines in the Far East of Russia, namely, the Chukotka Peninsula and the mouth of the Yana River, Magadan oblast, Primorye and the central part of Sakhalin Island, and the southern part of Sakhalin Island. Our data confirm that in the past the range of this species in the Far East was fragmented in several refugia that were isolated for a long time in various ice-free regions. This could have contributed to a high level of intraspecific polymorphism of green alder as a result of the divergence of endemic haplotypes, with almost non-overlapping distribution. However, the level of their molecular divergence does not correspond to the level of morphological differences.  相似文献   

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