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1.
Comparative analysis of personal sequence data for the mtDNA control region (926 to 928 bp) from eight-barbel loaches inhabiting eight localities in the Amur River basin (4) and the Sea of Japan (4) and the GeneBank/NCBI data for the Lefua individuals from the other regions of the world showed that eight-barbel loaches from Primorskii krai water basins were marked by a specific group of mtDNA haplotypes. This finding is considered as supporting the species status of L. pleskei. Genetic distances within L. pleskei are small (on average 0.355) and close to those within L. nikkonis (on average 0.48%). The distances between this species pair are the least (on average 2.15%) among all other pairs compared. In MP, ML, and Bayesian trees, L. pleskei and L. nikkonis haplotypes formed a common clade with high statistically significant support. In all tree variants, L. costata mtDNA haplotypes were located out of the group of interest. A clade consisting of highly diverged lineages of Lefua sp. and L. echigonia haplotypes occupied even more independent position. The mtDNA haplotypes of L. pleskei and L. costata from the Amur River basin were evolutionary young and derived from the haplotypes found in these species from the Sea of Japan (L. pleskei) or the Yellow Sea (L. costata) basins. It is thereby suggested that both species rather recently migrated into the Amur River system. According to the molecular clock data, basal diversification of the eight-barbel loach lineages took place at the end of middle Miocene (about 11 to 12 Myr ago), while divergence of L. pleskei and L. costata ancestral forms probably occurred approximately, 5 Myr ago. Since all main lineages of eight-barbel loaches were found in the Sea of Japan basin (continental coastline and the islands), the divergence order and dispersal patterns of the Lafua species might have been largely determined by the geological development pattern of this water body and the adjacent territories. 相似文献
2.
O. V. Apalikova M. G. Eliseikina M. Yu. Kovalev Vl. A. Brykov 《Russian Journal of Genetics》2008,44(7):873-880
The distribution of the diploid and triploid forms and the correspondence between ploidy and mitochondrial DNA (mtDNA) phylogenetic lineages of the silver crucian carp have been studied in Far Eastern water bodies and the Syr Darya River. Both diploid and triploid forms have been found in large river systems (the Amur, Suifun, Tumangan, and Syr Darya river basins). Only the diploid form has been detected in lakes of Bol’shoi Pelis Island (Peter the Great Bay of the Sea of Japan), Sakhalin Island, and the Kamchatka River basin (the Kamchatka Peninsula). It has been confirmed that there are two mtDNA phylogroups in the silver crucian carp in the area studied. Both mtDNA phylogenetic lineages are present in the Suifun and Tumangan river basins. Only one mtDNA phylogroup (characteristic of the gynogenetic form) has been detected in two samples from the Amur River and in the Syr Darya population. The other mtDNA phylogroup is predominant in insular populations and in Kamchatka. The gynogenetic form carries only mtDNA phylogroup I, whereas both phylogroups have been found in diploid bisexual fish. The existence of only two mtDNA phylogroups substantially differing from each other indicates that the gynogenetic form has emerged from the diploid form only once and evolved independently for a long time after that. The absence of haplotypes transitional between the two mtDNA phylogroups suggests that the secondary contact between the gynogenetic and bisexual forms in continental populations occurred within recent historical time. The obtained data confirm that genetic (though asymmetric) exchange between the two forms is possible, which explains the high morphological and, probably, genetic similarity between them. 相似文献
3.
The distribution of the diploid and triploid forms and the correspondence between ploidy and mitochondrial DNA (mtDNA) phylogenetic lineages of the silver crucian carp have been studied in Far Eastern water bodies and the Syr Darya River. Both diploid and triploid forms have been found in large river systems (the Amur, Suifun, Tumangan, and Syr Darya river basins). Only the diploid form has been detected in lakes of Bol'shoi Pelis Island (Peter the Great Bay of the Sea of Japan), Sakhalin Island, and the Kamchatka River basin (the Kamchatka Peninsula). It has been confirmed that there are two mtDNA phylogroups in the silver crucian carp in the area studied. Both mtDNA phylogenetic lineages are present in the Suifun and Tumangan river basins. Only one mtDNA phylogroup (characteristic of the gynogenetic form) has been detected in two samples from the Amur River and in the Syr Darya population. The other mtDNA phylogroup is predominant in insular populations and in Kamchatka. The gynogenetic form carries only mtDNA phylogroup I, whereas both phylogroups have been found in diploid bisexual fish. The existence of only two mtDNA phylogroups substantially differing from each other indicates that the gynogenetic form has emerged from the diploid form only once and evolved independently for a long time after that. The absence of haplotypes transitional between the two mtDNA phylogroups suggests that the secondary contact between the gynogenetic and bisexual forms in continental populations occurred within recent historical time. The obtained data confirm that genetic (though asymmetric) exchange between the two forms is possible, which explains the high morphological and, probably, genetic similarity between them. 相似文献
4.
Morphological and genetic characteristics are used for the analysis of the origin of charrs from the lakes of the Kolyma basin (Chuk, Gek, Gulyaevskoe-4, Gulyaevskoe-6, and Lenkovoe) and the Sea of Okhotsk basin (Lake Chistoe). In addition to these samples, the fragments of the control region of mitochondrial DNA (CR mtDNA, 550-bp) and exon 2 of recombination activating gene 1 (RAG1, 899-bp) are sequenced in the charrs from lakes Dzhul’etta and Cherechen’ (Kolyma basin) and lakes Elikchanskie, Bol’shoi Mak-Mak, Ueginskoe (Sea of Okhotsk basin), Ulakhan-Silyan-Kyuel’ (Yana River basin) as well as in northern Dolly Varden from the Kamchatka River. The charr from Lake Chistoe is represented by northern Dolly Varden. In the charrs from lakes Chuk, Gek, Gulyaevskoe-4, Gulyaevskoe-6, Lenkovoe, Cherechen’, Elikchanskie, Bol’shoi Mak-Mak, and Ueginskoe, the haplotypes of mtDNA of the Bering group (a haplogroup of northern Dolly Varden) are revealed. Based on the morphological and RAG1 data, populations of charrs from these lakes belong to the Salvelinus alpinus complex. A transfer of mtDNA of northern Dolly Varden to the charrs from the Kolyma and Sea of Okhotsk basins occurred during the last postglacial expansion and subsequent hybridization. Based on the results of morphological and genetic analysis, the charrs from the Kolyma and Sea of Okhotsk basins cannot be unambiguously referred to the phylogenetic groups of Eurasian Arctic charr or Taranets charr. The presence of mtDNA haplotypes of the Arctic group (a haplogroup of Taranets charr) in the populations of lakes Dzhul’etta, Maksi, and Ueginskoe shows a possibility of their belonging to the group of Taranets charr. 相似文献
5.
In the loach Misgurnus anguillicaudatue, the asexual lineage, which produces unreduced clonal diploid eggs, has been identified. Among 833 specimens collected from
54 localities in Japan and two localities in China, 82 candidates of other lineage(s) of cryptic clones were screened by examining
RFLP (restriction fragment length polymorphism)-PCR haplotypes in the control region of mtDNA. This analysis was performed
because triploid loaches arise from the accidental incorporation of the sperm nucleus into unreduced diploid eggs of a clone.
The categorization of members belonging to three newly identified lineages (clones 2–4) and the previously identified clonal
lineage (clone 1) was verified by evaluating the genetic identity between two or more individuals from each clonal lineage
based on RAPD (random amplified polymorphic DNA)-PCR and multilocus DNA fingerprints. We detected 75 haplotypes by observing
the nucleotide status at variable sites from the control region of mtDNA. Phylogenic trees constructed from such sequences
showed two highly diversified clades, A and B, that were beyond the level common for interspecific genetic differentiation.
That result suggests that M. anguillicaudatus in Japan is not a single species entity. Two clone-specific mtDNA sequences were included in clade A, and the loaches with
such sequences may be the maternal origin of the clones.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
6.
Mitochondrial DNA (mtDNA) sequences were used to infer the phylogenetic relationships of Prochilodus species in the Paraná, Amazonas, Orinoco, and Magdalena basins. Sequences of ATPase subunits 6 and 8 (total 840 bp) were obtained for 21 Prochilodus specimens from the four river systems. Using Semaprochilodus as an outgroup, phylogenetic analyses showed that: (i) each river basin contains a monophyletic group of mtDNA lineages; and (ii) the branching order places Magdalena in a basal position with subsequent branching of Orinoco, Amazon and Paraná. The mitochondrial control region was sequenced for 26 P. lineatus (from the Paraná basin) and six other Prochilodus specimens from the Magdalena, Orinoco and Amazon. All 26 control region haplotypes were unique with sequence divergence ranging from 0.3 to 3.6%. The control region phylogeny is well resolved but phylogenetic structure is not associated with geography. For example, mtDNA haplotypes from the upper Paraná (Mogui Guassú) and the upper Bermejo, separated by at least 2600 km, have close genealogical ties. Phylogeographic analyses, including nested clade analysis, suggest high levels of gene flow within this basin. 相似文献
7.
S. V. Shedko L. K. Ginatulina I. L. Miroshnichenko G. A. Nemkova 《Russian Journal of Genetics》2007,43(2):165-176
In 41 individuals of South Asian Dolly Varden char Salvelinus curilus, nucleotide sequences of tRNA-Pro gene fragment (27 bp) and mtDNA control region (483–484 bp) were analyzed. The fish were collected in 20 localities covering virtually the whole range of the species: Kuril Islands, Sakhalin Island, and Primorye. In addition, six individuals of three other char species (S. albus, S. malma, and S. leucomaenis), which are closely related to S. curilus and inhabit the Russian Far East, were examined. In all, we detected 12 different variants of mtDNA haplotypes that formed three distinct groups differing in 14–20 nucleotide positions. The first group consisted of six haplotypes found in S. curilus in Kuril Islands, Sakhalin, and Primorye (mtDNA phylogroup OKHOTSKIA). The second group comprised four haplotypes representing the mtDNA phylogroup BERING, which had been described earlier (Brunner et al, 2001); they were found in S. curilus in Kuril Islands and Sakhalin, as well as in S. albus and S. malma in Kamchatka and northern Kurils. The third group included two haplotypes detected in S. leucomaenis. The existence of two mtDNA lineages (OKHOTSKIA and BERING) in S. curilus from Kurils and Sakhalin was explained by hybridization and mtDNA transfer from S. malma to S. curilus. The absence of the BERING haplotypes in S. curilus from Primorye water reservoirs is related to the physical isolation of the Sea of Okhotsk and Sea of Japan basins in past epochs. On the basis of comparing phylogenetic trees, constructed from the data on allozyme and mtDNA variation, we suggest that in this case, a mediated transfer of mtDNA in Alpinoid chars → S. malma → S. curilus chain could occur. 相似文献
8.
Huahua Fang Junli Zhang Na Song Long Qian Tianxiang Gao 《Russian Journal of Genetics》2013,49(10):1047-1056
The burbot (Lota lota Linnaeus, 1758) is the only freshwater species of the family Gadidae. There is a longstanding controversy about taxonomic status of the burbot from the Amur River basin. It is necessary to investigate population genetic structure and geographical differentiation among burbot populations from the Irtysh River basin and Amur River basin by mitochondrial DNA nucleotide sequence analysis. A 572 bp segment of cytochrome b and 425 bp segment of control region gene were sequenced from 4 populations. The results showed that there was lower genetic diversity of burbot in China and highly significant genetic difference between populations in the Amur River basin (P < 0.01). Demographic analysis indicated that the burbot from the Amur River basin experienced population expansion (Cytb: F S = ? 0.912 (P = 0.287), D = ? 0.399 (P = 0.375); CR: F S = ?4.771 (P = 0.015), D = ?1.523 (P = 0.03)). The data of 4 populations in China combining with the published data representing the Eurasian and North American burbot, revealed three distinct phylogenetic lineages (labelled EB, NA, Amur). 相似文献
9.
Akira Ooyagi Daniel F. Mokodongan Javier Montenegro Ixchel F. Mandagi Noriyuki Koizumi Yoshiyasu Machida Nobuyuki Inomata Sergey V. Shedko Arief A. Hutama Renny K. Hadiaty Kazunori Yamahira 《Ichthyological Research》2018,65(1):115-126
Many straits in the Japanese archipelago have been proposed as biogeographical boundaries, but there is disagreement regarding their importance as historic barriers against dispersal of terrestrial and freshwater taxa. Mitochondrial DNA haplotype and phylogenetic analyses of Lefua nikkonis, a primary freshwater fish inhabiting northern Japan and descendent from Siberia, revealed that the species is genetically structured within its geographic range, but that two major haplotypes are widely distributed across the Ishikari Lowland of Hokkaido Island as well as across the Tsugaru Strait between Hokkaido and Honshu Islands, two well-known biogeographical boundaries of northern Japan. The two major haplotypes were separated from each other by only one mutational step, and many other haplotypes, including those endemic to the region south of these barriers, have diverged from the major haplotypes, suggesting rapid range expansion and local differentiation. Divergence-time estimates, based on vicariance of the Honshu endemic congener L. echigonia via uplift of the Central Highlands, demonstrated that the southward dispersal of L. nikkonis from Hokkaido Island to Honshu Island occurred less than 0.08–0.19 Mya, suggesting that a land bridge emerged at the Tsugaru Strait during the Riss glaciation. Given that other freshwater taxa crossed the strait earlier (during the Middle Pleistocene), it is likely that land bridges in the strait have repeatedly emerged. The fact that L. nikkonis invaded only the northern part of Honshu, and that many other freshwater species also have the limit of their distribution ranges in this area as well, indicates that a faunal transition zone might persist even without the Tsugaru Strait. Thus, straits and lowlands in northern Japan are likely to have been less important as dispersal barriers to freshwater taxa than is currently thought. 相似文献
10.
This paper studies the species composition and quantitative distribution of diatoms that belong to the genus Pseudo-nitzschia in the Russian waters of the Sea of Japan and the Sea of Okhotsk. In total, 11 species of this genus were found in the area, including 7 that are known as being potentially toxic. The highest concentrations of Pseudo-nitzschia microalgae (1.4 × 106–2.7 × 106 cells/L) were found in the summer and autumn in the Peter the Great Bay of the Sea of Japan and the lowest concentrations (2.5 × 102–1 × 104 cells/L) were found in the Sakhalinsky and Akademiya bays of the Sea of Okhotsk. The species diversity of potentially toxic diatoms was greatest (seven species) and the cell concentrations highest (over 6 × 105 cells/L) in the Peter the Great Bay, Sea of Japan, and in the Aniva Bay, Sea of Okhotsk. The density of potentially toxic species was highest near the northeastern coast of Sakhalin Island, in the Amur River estuary, and in adjacent waters. This paper also presents geographical distribution maps of Pseudo-nitzschia species and maps of the density distribution of potentially toxic microalgae over the studied area and identifies potential amnesic shellfish poisoning areas. 相似文献
11.
A. V. Semina N. E. Polyakova M. A. Makhotkin V. A. Brykov 《Russian Journal of Marine Biology》2007,33(3):187-192
Three Mugilid species: Mugil cephalus (Linnaeus, 1758) and Liza haematocheila (Temminck et Schlegel, 1845; syn. Mugil soiuy, M. haematocheilus, L. soiuy, Chelon haematocheilus) from the Sea of Japan, as well as M. cephalus and Liza aurata (Risso, 1810) from the Sea of Azov were investigated on the basis of PCR-RFLP analysis of mitochondrial DNA (mtDNA) fragments, which included 12S/16S rRNA, and ND3/ND4L/ND4 genes. Among 61 individuals of three Mugilid species thirteen different haplotypes were detected. Eight and thirteen restriction endonucleases were found to be species-specific in 12S/16SrRNA and ND3/ND4L/ND4 respectively. This method may be useful for species identification. M. cephalus showed the largest genetic divergence while L. haematocheila and L. aurata were closely related and clustered together. The level of mtDNA differentiation between the two M. cephalus samples from the Sea of Japan and the Sea of Azov, i.e., nucleotide substitutions of approximately 3%, appeared to be relatively high. 相似文献
12.
I. Hashemzadeh Segherloo H. Farahmand A. Abdoli L. Bernatchez C. R. Primmer A. Swatdipong M. Karami B. Khalili 《Journal of fish biology》2012,81(5):1479-1500
Interrelationships, origin and phylogenetic affinities of brown trout Salmo trutta populations from the southern Caspian Sea basin, Orumieh and Namak Lake basins in Iran were analysed from complete mtDNA control region sequences, 12 microsatellite loci and morphological characters. Among 129 specimens from six populations, seven haplotypes were observed. Based on mtDNA haplotype data, the Orumieh and southern Caspian populations did not differ significantly, but the Namak basin–Karaj population presented a unique haplotype closely related to the haplotypes of the other populations (0·1% Kimura two‐parameter, K2P divergence). All Iranian haplotypes clustered as a distinct group within the Danube phylogenetic grouping, with an average K2P distance of 0·41% relative to other Danubian haplotypes. The Karaj haplotype in the Namak basin was related to a haplotype (Da26) formerly identified in the Tigris basin in Turkey, to a Salmo trutta oxianus haplotype from the Aral Sea basin, and to haplotype Da1a with two mutational steps, as well as to other Iranian haplotypes with one to two mutational steps, which may indicate a centre of origin in the Caspian basin. In contrast to results of the mtDNA analysis, more pronounced differentiation was observed among the populations studied in the morphological and microsatellite DNA data, except for the two populations from the Orumieh basin, which were similar, possibly due to anthropogenic causes. 相似文献
13.
Sexual size dimorphism,growth, and maturity of the fluvial eight-barbel loach in the Kako River,Japan 总被引:1,自引:0,他引:1
Shigeru Aoyama 《Ichthyological Research》2007,54(3):268-276
The maturation and growth pattern of the fluvial eight-barbel loach Lefua sp. (Japanese name: nagare-hotoke-dojo), an endangered species, was investigated using an individual identification-recapture
method from 1995 to 1998 in an upper reach of a headwater tributary of the Kako River, Hyogo Prefecture, Japan. Based on observations
of the gonads through the abdominal skin, the loach was estimated to breed mostly from May to July. All the males matured
by age 1+, and all the females matured by age 2+. Gamete release in all individuals of both males and females was predicted from recaptured loaches during each breeding season.
The standard length of mature females was significantly larger than that of males, showing sexual size dimorphism (SSD). The
maximum sizes recorded were 75.4 mm SL for females and 61.2 mm SL for males. Both males and females of immature specimens
grew mainly from May to November, including the breeding season, with no significant differences in growth rates between them.
After sexual maturity, both males and females grew mainly from July to October (or November), after the breeding season, and
the females exhibited higher growth rates than males. Therefore, SSD of the species seems to be attributable to the different
growth rates after maturity. The longevity of the loach was estimated to exceed ten years based on individual growth patterns
of various sizes during the survey period. It is likely that the loach has an iteroparous life history, breeding every year,
and moderate growth rates after maturity. 相似文献
14.
Aim Hidden diversity within an invasive ‘species’ can mask both invasion pathways and confound management goals. We assessed taxonomic status and population structure of the monkey goby Neogobius fluviatilis across Eurasia, comparing genetic variation across its native and invasive ranges. Location Native populations were analysed within the Black and Caspian Sea basins, including major river drainages (Dnieper, Dniester, Danube, Don and Volga rivers), along with introduced locations within the upper Danube and Vistula river systems. Methods DNA sequences and 10 nuclear microsatellite loci were analysed to test genetic diversity and divergence patterns of native and introduced populations; phylogenetic analysis of mtDNA cytochrome b and nuclear RAG‐1 sequences assessed taxonomic status of Black and Caspian Sea lineages. Multivariate analysis of morphology was used to corroborate phylogenetic patterns. Population genetic structure within each basin was evaluated with mtDNA and microsatellite data using FST analogues and Bayesian assignment tests. Results Phylogenetic analysis of mitochondrial and nuclear sequences discerned a pronounced genetic break between monkey gobies in the Black and Caspian Seas, indicating a long‐term species‐level separation dating to c. 3 million years. This pronounced separation further was confirmed from morphological and population genetic divergence. Bayesian inference showed congruent patterns of population structure within the Black Sea basin. Introduced populations in the Danube and Vistula River basins traced to north‐west Black Sea origins, a genetic expansion pattern matching that of other introduced Ponto‐Caspian gobiids. Main conclusions Both genetic and morphological data strongly supported two species of monkey gobies that were formerly identified as subspecies: N. fluviatilis in the Black Sea basin, Don and Volga Rivers, and the Kumo‐Manych Depression, and Neogobius pallasi in the Caspian Sea and Volga River delta. Genetic origins of introduced N. fluviatilis populations indicated a common invasion pathway shared with other introduced Ponto‐Caspian fishes and invertebrates. 相似文献
15.
We examined the genetic population structure of Lefua echigonia (Japanese name, hotoke-dojo) using polymerase chain reaction restriction-fragment length polymorphisms (PCR-RFLPs) of the mitochondrial cytochrome b gene and two allozymic loci. The phylogenetic relationships of L. echigonia and those among L. echigonia, Lefua sp. (nagare hotoke-dojo), and L. nikkonis (ezo hotoke-dojo) were also investigated based on the nucleotide sequences of the cytochrome b gene. PCR-RFLP analysis revealed 18 mitotypes in L. echigonia, 2 in Lefua sp., and 1 in L. nikkonis. Phylogenetic trees based on the cytochrome b sequences indicated that the 18 mitotypes in L. echigonia were divided into five distinct groups (South-Kanto, North-Kanto, Tohoku, Echigo, and Tokai-Kinki clades) that differed by 8.5–15.3%, reflecting region-specific geographic distributions. The distributions of alleles in two allozymic loci roughly corresponded to those of the mitotype groups. The divergence times of the five groups were estimated to be about 3.4–7.7 million years ago by applying a general rate for mitochondrial DNA, suggesting that the divergence among them might have occurred in the late Tertiary. It can be inferred that the regional differentiation of each group was mainly due to geographic isolation and that this has been maintained, because the boundaries among the groups corresponded to geological features. The trees also supported the existence of three taxa, L. echigonia, Lefua sp., and L. nikkonis. We concluded that Lefua sp. was distinguished from other species in Lefua by morphological and ecological characters and also by genetic divergences of the cytochrome b gene. Our study also demonstrated the superior efficacy and simplicity of PCR-RFLP analysis as a method for detecting genetic variation in L. echigonia. 相似文献
16.
Andrey P. Shmigirilov Anastassia A. Mednikova Joshua A. Israel 《Environmental Biology of Fishes》2007,79(3-4):383-395
Three Acipenseridae species live in the rivers and marine waters of the Khabarovsk Territory, Russia: Sakhalin sturgeon, Acipenser mikadoi, Amur sturgeon, A. schrenckii, and kaluga, Huso dauricus. We review the general biology and life history of each species, including their historic and current distributions, and
examine current paleogeographic theories to outline the possible origin and evolution of these three species in the Amur River,
Sea of Okhotsk, and Sea of Japan biogeographic province. Apparently, these species have evolved during distinct geologic time
periods, which has reinforced the reproductive isolation of these species although hybridization does occur. They have convergently
adapted to the unique environmental conditions of the Amur River and Russian Maritime regions, and yet developed behavioral
adaptations to reduce competition between species. Sakhalin sturgeon is the least studied species among anadromous sturgeon
in the world. This species is highly migratory and spends the majority of its life in the ocean only returning to natal rivers
to spawn. Amur sturgeon and kaluga are distributed throughout the Amur River basin and the estuary and share many life history
traits. They are both represented by distinct morphs. Additionally, we present size and weight relationships to estimate the
growth of Amur sturgeon and kaluga. All three species have suffered declines in abundance due to over fishing and their contemporary
distributions have contracted compared to their historic ranges. We identify gaps in knowledge and suggest further research
useful for guiding management of each species. 相似文献
17.
Background
The marginal seas of northwestern Pacific are characterized by unique topography and intricate hydrology. Two hypotheses have been proposed to explain genetic patterns of marine species inhabiting the region: the historical glaciations hypothesis suggests population genetic divergence between sea basins, whereas the Changjiang River outflow hypothesis suggests genetic break in line with the Changjiang Estuary. Here the phylogeography of bivalve Cyclina sinensis was investigated to test the validity of these two hypotheses for intertidal species in three marginal seas—the East China Sea (ECS), the South China Sea (SCS), and the Japan Sea (JPS).Methodology/Principal Findings
Fragments of two markers (mitochondrial COI and nuclear ITS-1) were sequenced for 335 individuals collected from 21 populations. Significant pairwise ΦST were observed between different marginal sea populations. Network analyses illustrated restricted distribution of haplogroups/sub-haplogroups to sea basins, with a narrow secondary contact zone between the ECS and SCS. Demographic expansion was inferred for ECS and SCS lineages using mismatch distributions, neutral tests, and extended Bayesian Skyline Plots. Based on a molecular clock method, the divergence times among COI lineages were estimated dating from the Pleistocene.Conclusions
The phylogeographical break revealed for C. sinensis populations is congruent with the historical isolation of sea basins rather than the putative Changjiang River outflow barrier. The large land bridges extending between seas during glaciation allowed accumulation of mutations and subsequently gave rise to deep divergent lineages. The low-dispersal capacity of the clam and coastal oceanography may facilitate the maintenance of the historical patterns as barriers shift. Our study supports the historical glaciations hypothesis for interpreting present-day phylogeographical patterns of C. sinensis, and highlights the importance of historical glaciations for generating genetic structure of marine coastal species especially those with low-dispersal abilities in northwestern Pacific. 相似文献18.
Steven Weiss Giulia Secci-Petretto Alexander Antonov Elsa Froufe 《Zoologica scripta》2020,49(1):117-128
Large-scale phenotypic and genetic studies of the salmonid genus Thymallus (grayling) in the Palaearctic suggest that most major phylogeographic lineages represent good biological species. Evaluating such a premise in areas involved in palaeo-hydrological dynamics where multiple species are found in sympatry should serve to assess the level of reproductive isolation, the traditional sine qua non of species recognition. Molecular sequence (mtDNA) and microsatellite (nDNA, seven loci) analysis of grayling in the upper Bureya River watershed support the occurrence of three distinctive species of grayling living in sympatry in this large oligotrophic tributary of the Amur River. One of these lineages is primarily found throughout the Lena River basin and is recognized as Baikal-Lena grayling Thymallus baicalolenensis; the second, the upper Amur grayling Thymallus grubii is found over large areas of the Amur catchment including the entire headwater region; and the third, the Bureya grayling Thymallus burejensis is endemic to the study area. A limited number of hybrids were identified, primarily between Baikal-Lena grayling T. baicalolenensis and Bureya grayling T. burejensis with little to no signs of introgression among non-hybrid individuals. Morphological distinctiveness among populations of these species living in sympatry was greater than between populations living in allopatry, suggesting character displacement. Divergence estimates among taxa range up to 6.2 MY, and allopatric origins for all three species’ is suggested. To our knowledge, this is the first data-based confirmation of three species of grayling living in sympatry. 相似文献
19.
Spined loaches from the Veleka River (Black Sea coast of Bulgaria), earlier confirmed to represent a separate evolution lineage within a 50-chromosome morph occurring in the Black Sea basin, are described as a new species. This species has the karyotype (2n = 50, NF = 90) similar to one from earlier described C. taurica occurring in the Crimean Peninsula, but differs from it by larger and less numerous spots in the fourth Gambetta’s zone of pigmentation and more anterior position of suborbital spine. 相似文献
20.
Analysis of the mtDNA control region in six individual brown trout Salmo trutta from the Catak Cay River (Tigris basin) revealed a single, new, haplotype, 1·0 to 1·5% divergent from five other Da lineage haplotypes analysed, that groups with the Danubian clade with low bootstrap support. This highly divergent haplotype combined with unique phenotypic characteristics underscores the novelty and native status of this population, which has probably been isolated from other brown trout lineages for at least several hundred thousand years. 相似文献