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1.
Vet Parasitol ; 302: 109646, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34999317

RESUMO

The discovery of hybrids between Ascaris lumbricoides and Ascaris suum has complicated our understanding of the relationship between the two species. We examined the same Ascaris specimens (48 from humans and 48 from pigs) using two methods: microsatellite markers combined with Bayesian clustering and PCR-RFLP of the nuclear internal transcribed spacer region. The results obtained by the two methods were inconsistent but showed that hybrid Ascaris identified through both approaches could infect pigs. The results of this study suggest that PCR-RFLP of ITS alone is not suitable for molecular identification of human-type and pig-type Ascaris hybrids. Use of multiple SSR markers combined with Bayesian analysis was the most reliable method in our study. Our results indicate that, in addition to host-specific Ascaris types, there may be some that do not show host specificity. Our results show for the first time that hybrid individuals can infect pigs as well as humans. This study has important theoretical and practical implications, including suggesting the need to re-evaluate long-term ascariasis control strategies.

2.
Mitochondrial DNA B Resour ; 6(9): 2575-2577, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34377833

RESUMO

The genus Cuneopsis Simpson, 1900 comprises seven valid species, and Cuneopsis celtiformis (Heude, 1874) is the type species of this genus. Previous phylogenetic studies using complete mitochondrial genomes showed that Cuneopsis was not monophyletic, but the result was hampered by incomplete species sampling and lack of the type species of this genus. In this study, we collected C. celtiformis from the type locality and determined its complete maternal mitochondrial genome. This mitogenome is 15,922 bp in length and contains 14 protein-coding genes (including one F-orf), two rRNA genes, 22 tRNA genes, and 1 putative control region. Our mitochondrial phylogenomic analysis confirms that currently recognized genus Cuneopsis is polyphyletic, and C. celtiformis is the closest to C. heudei with high maximum likelihood bootstrap support value. Comprehensive sampling of all Cuneopsis species is needed for phylogenetic analysis to erect new genera in future studies.

3.
Zookeys ; 1054: 85-93, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34393564

RESUMO

We diagnose and describe a new freshwater mussel species of the genus Inversidens, I.rentianensis sp. nov. from Jiangxi Province, China based on morphological characters and molecular data. This paper includes a morphological description and photograph of the holotype, and partial sequences of mitochondrial COI as DNA barcode data.

4.
Mitochondrial DNA B Resour ; 6(5): 1627-1629, 2021 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-34027076

RESUMO

Clausiliidae snails have been of great interest to conchologists for their unique clausilium structure and rich species diversity. We described the complete mitochondrial genome of Euphaedusa planostriata (Heude, 1882). The mitogenome is 15,041bp in length, with a total of 37 genes, including 13 protein-coding genes, 2 rRNA genes, and 22 tRNA genes. It is consistent with the basic characteristics of the known stylommatophoran mitochondrial genome. Phylogenetic analysis using mitogenomes showed that Euphaedusa planostriata is clustered with Albinaria caerulea, supporting the monophyly of this family. Our study provides valuable information that can be used toward the conservation genetics, taxonomy and evolution of clausiliid snails.

5.
Ecol Evol ; 11(24): 17885-17900, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35003645

RESUMO

Anthropogenic habitat alteration interferes the natural aquatic habitats and the system's hydrodynamics in the Yangtze River floodplain lakes, resulting in a serious decline in freshwater biodiversity. Zooplankton communities possess major position in freshwater ecosystems, which play essential parts in maintaining biological balance of freshwater habitats. Knowledge of processes and mechanisms for affecting variations in abundance, biomass, and diversity of zooplankton is important for maintaining biological balance of freshwater ecosystems. Here, we analyzed that the temporal and spatial changes in the structure of zooplankton community and their temporal and spatial variations respond to changes in environmental factors in the middle reach of Yangtze River floodplain lakes. The results showed that zooplankton samples were classified into 128 species, and Rotifera was the most common taxa. Significant seasonal differences were found among the abundance and diversity of zooplankton. Similarly, we also found significant seasonal differences among the biomass of zooplankton functional groups. The spatial turnover component was the main contributor to the ß diversity pattern, which indicated that study areas should establish habitat restoration areas to restore regional biodiversity. The NMDS plot showed that the structure of zooplankton community exhibited significant seasonal changes, where the community structure was correlated with pH, water temperature, water depth, salinity, total nitrogen, chlorophyll-a, and total phosphorus based on RDA. This study highlights that it is very important to ensure the floodplain ecosystem's original state of functionality for maintaining the regional diversity of the ecosystem as a whole.

6.
Ecol Evol ; 10(21): 12015-12023, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33209266

RESUMO

Freshwater mussels are both among the most diverse and endangered faunas worldwide. The gut microbiota of species plays a key role in nutrition and immunity, such as preventing it from pathogen invasion, synthesizing beneficial secondary metabolites, and contributing to the digestion of complex nutrients. Information on the gut microbiota could have significant implications for conservation biology, especially for threatened or endangered species. However, there is relatively little study into the gut microbiota of freshwater mussels. Here, the gut microbiota diversity was analyzed in endangered (Solenaia carinata), economical (Sinohyriopsis cumingii), and common (Sinanodonta woodiana) freshwater mussels using 16S rRNA gene sequencing. This study represents the first to compare the gut microbiota diversity of endangered, economical, and common Chinese freshwater mussels. The results showed that 13,535 OTUs were found in S. carinata, 12,985 OTUs in S. cumingii, and 9,365 OTUs in S. woodiana. The dominant phylum in S. carinata and S. cumingii was Fusobacteria, and was Firmicutes in S. woodiana. Alpha diversity indices indicated that S. carinata and S. cumingii had a higher abundance and diversity of gut microbiota than S. woodiana. The composition of gut microbiota was different among three freshwater mussels, but their composition variation was not significant. This study provides insight for the conservation of freshwater mussel biodiversity, which will not only help conserve these vulnerable groups but also, will offer wider benefits to freshwater ecosystems.

7.
Vet Parasitol ; 287: 109256, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-33053491

RESUMO

Ascaris lumbricoides and Ascaris suum are parasitic nematodes in human and pig intestines. The two species can cross infect and produce hybrids, which contribute to the controversy concerning the taxonomy of A. lumbricoides and A. suum. The purpose of this study was to investigate the microevolutionary process and evolutionary history of human-type Ascaris, pig-type Ascaris, and hybrid Ascaris and provide a theoretical basis for the prevention and control of human and animal ascariasis. The mitochondrial phylogenomics of human-type Ascaris (n = 5), pig-type Ascaris (n = 6), and hybrid Ascaris (n = 6) populations were analyzed using high-throughput sequencing technology. The mitochondrial genomes of human-type Ascaris, pig-type Ascaris, and hybrid Ascaris contained 36 genes (atp8 was missing), including 12 protein-coding genes, 2 rRNA genes, and 22 tRNA genes. All genes were located on the heavy chain. The initiation codons used for protein-coding genes were ATT and TTG and the termination codons were TAA and TAG. The base distribution showed obvious AT preference. The phylogenetic tree based on the Ascaris mitochondrial genomes showed three main clusters (A, B, and C). The Ascaris populations sequenced in this study were all gathered in cluster B. The human-type and hybrid Ascaris populations belonged to different sub-clusters, but the pig-type Ascaris population was more scattered. The mitochondrial genome sequences of the 17 Ascaris individuals in this study did not differ much. The results of this study indicate that Ascaris populations were geographically isolated before host shift. In addition, the data show that there are differences between hybrid Ascaris, human-type Ascaris, and pig-type Ascaris. The information has important theoretical significance and application value.

8.
PeerJ ; 8: e9657, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32953257

RESUMO

The freshwater clam Corbicula fluminea s.l. is an edible freshwater bivalve of economic value in Asia. The species has been particularly well studied in the invaded range. However, there is a lack of knowledge in its native range where it supports an increasing commercial harvest pressure. Among Asiatic countries, China accounts for 70% of known commercial harvest and aquaculture production. We aim to characterize here wild C. fluminea s.l populations exposed to commercial harvest pressure in Poyang Lake Basin. We found higher biomass, density and genetic diversity in lake populations compared to peripheral populations (i.e., lake tributaries). Given that lake habitats support more intense harvest pressure than peripheral habitats, we suggest that demographic and genetic differentiation among subpopulations may be influenced in some degree by different harvest pressure. In this regard, additional demographic and/or genetic changes related to increasing harvest pressure may place population at a higher risk of extirpation. Altogether, these results are especially relevant for maintaining populations at or above viable levels and must be considered in order to ensure the sustainability of the resource.

9.
Hypertension ; 76(3): 827-838, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32683902

RESUMO

NOX5 (NADPH oxidase 5) is a homolog of the gp91phox subunit of the phagocyte NOX, which generates reactive oxygen species. NOX5 is involved in sperm motility and vascular contraction and has been implicated in diabetic nephropathy, atherosclerosis, and stroke. The function of NOX5 in the cardiac hypertrophy is unknown. Because NOX5 is a Ca2+-sensitive, procontractile NOX isoform, we questioned whether it plays a role in cardiac hypertrophy. Studies were performed in (1) cardiac tissue from patients undergoing heart transplant for cardiomyopathy and heart failure, (2) NOX5-expressing rat cardiomyocytes, and (3) mice expressing human NOX5 in a cardiomyocyte-specific manner. Cardiac hypertrophy was induced in mice by transverse aorta coarctation and Ang II (angiotensin II) infusion. NOX5 expression was increased in human failing hearts. Rat cardiomyocytes infected with adenoviral vector encoding human NOX5 cDNA exhibited elevated reactive oxygen species levels with significant enlargement and associated increased expression of ANP (atrial natriuretic peptides) and ß-MHC (ß-myosin heavy chain) and prohypertrophic genes (Nppa, Nppb, and Myh7) under Ang II stimulation. These effects were reduced by N-acetylcysteine and diltiazem. Pressure overload and Ang II infusion induced left ventricular hypertrophy, interstitial fibrosis, and contractile dysfunction, responses that were exaggerated in cardiac-specific NOX5 trangenic mice. These phenomena were associated with increased reactive oxygen species levels and activation of redox-sensitive MAPK (mitogen-activated protein kinase). N-acetylcysteine treatment reduced cardiac oxidative stress and attenuated cardiac hypertrophy in NOX5 trangenic. Our study defines Ca2+-regulated NOX5 as an important NOX isoform involved in oxidative stress- and MAPK-mediated cardiac hypertrophy and contractile dysfunction.


Assuntos
Acetilcisteína/farmacologia , Cardiomegalia , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , NADPH Oxidase 5/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Angiotensina II/farmacologia , Animais , Cardiomegalia/tratamento farmacológico , Cardiomegalia/metabolismo , Sequestradores de Radicais Livres/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Isoenzimas/metabolismo , Camundongos , Camundongos Transgênicos , Miócitos Cardíacos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fagócitos/enzimologia , Ratos , Transdução de Sinais/efeitos dos fármacos , Vasoconstritores/farmacologia , Miosinas Ventriculares/metabolismo
10.
Hepatology ; 72(2): 389-398, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32359177

RESUMO

BACKGROUND AND AIMS: Coronavirus disease 2019 (COVID-19) is a new infectious disease. To reveal the hepatic injury related to this disease and its clinical significance, we conducted a multicenter retrospective cohort study that included 5,771 adult patients with COVID-19 pneumonia in Hubei Province. APPROACH AND RESULTS: We reported the distributional and temporal patterns of liver injury indicators in these patients and determined their associated factors and death risk. Longitudinal liver function tests were retrospectively analyzed and correlated with the risk factors and death. Liver injury dynamic patterns differed in alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), and total bilirubin (TBIL). AST elevated first, followed by ALT, in severe patients. ALP modestly increased during hospitalization and largely remained in the normal range. The fluctuation in TBIL levels was mild in the non-severe and the severe groups. AST abnormality was associated with the highest mortality risk compared with the other indicators of liver injury during hospitalization. Common factors associated with elevated liver injury indicators were lymphocyte count decrease, neutrophil count increase, and male gender. CONCLUSION: The dynamic patterns of liver injury indicators and their potential risk factors may provide an important explanation for the COVID-19-associated liver injury. Because elevated liver injury indicators, particularly AST, are strongly associated with the mortality risk, our study indicates that these parameters should be monitored during hospitalization.


Assuntos
Betacoronavirus , Infecções por Coronavirus/mortalidade , Infecções por Coronavirus/fisiopatologia , Fígado/fisiopatologia , Pneumonia Viral/mortalidade , Pneumonia Viral/fisiopatologia , Adulto , Idoso , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Aspartato Aminotransferases/sangue , Bilirrubina/sangue , Biomarcadores , COVID-19 , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Pandemias , Estudos Retrospectivos , SARS-CoV-2
11.
Vet Parasitol ; 279: 109062, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32126343

RESUMO

Ascaris lumbricoides and Ascaris suum are parasitic nematodes that mainly parasitize the small intestines of people and pigs, respectively. Ascariasis seriously endangers human health and causes huge economic losses in the pig industry. A. lumbricoides and A. suum have similar morphologies and genetic structures, and occasionally these organisms cross-infect the alternate host. Therefore, their taxonomies are controversial. In this study, the whole genomes of A. lumbricoides (n = 6) and A. suum (n = 6) were resequenced using a HiSeq X Ten sequencing platform. Phylogenetic, principal component, and population structure analyses showed clear genetic differentiation between the two Ascaris populations. Linkage disequilibrium analysis indicated that the A. lumbricoides population was more primitive than the A. suum population. In the selective elimination analysis, 160 and 139 candidate regions were screened in A. lumbricoides and A. suum, respectively, and the selected regions were analyzed by Gene Ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses. The A. lumbricoides population had no significant enrichment in GO terms, but two KEGG pathways, the RNA degradation and tyrosine metabolism pathways, were significantly enriched. Five GO entries and one KEGG pathway, the alanine, aspartate, and glutamate metabolism signaling pathway, were significantly enriched in the A. suum population. An analysis of the demographic histories of Ascaris populations revealed that A. lumbricoides and A. suum had similar trends in effective population size in different historical periods. Ascaris populations peaked about 1 million years ago and then began to decline. In the last glacial period, they dropped to a historical low and continued at this level until the last glacial maximum. This phenomenon may be associated with the cold climate at that time. This study provides new information on the genetic differentiation, evolutionary relationships, gene functional enrichment, and population dynamics of Ascaris populations, with implications for host differences, evolution, and classification of A. lumbricoides and A. suum.


Assuntos
Ascaris lumbricoides/genética , Ascaris suum/genética , Genoma Helmíntico , Animais , Sequenciamento Completo do Genoma/veterinária
12.
Ecol Evol ; 9(20): 11672-11683, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31695877

RESUMO

Poyang Lake Basin is of great importance to maintain regional ecological balance. However, fish biodiversity in this basin has rapidly declined as the result of anthropogenic habitat alteration, such as dam construction, sand mining, and water pollution. Here, we aimed to analyze the temporal and spatial changes in biodiversity patterns of fish in Poyang Lake Basin over the last 37 years. The number of fish species underwent a significant decrease in the current period. In particular, 36.7% of the migration of fish was extirpated. Twenty-seven fish species have been formally assessed using the Chinese Red List were currently listed as Critically Endangered (9), Endangered (3), Vulnerable (10), and Near Threatened (5). Alpha and gamma diversity revealed that fish diversity had also decreased, and beta diversity showed significant composition dissimilarity in two periods. PCoA showed that the historical fish composition dissimilarity was significantly different from that of the current period. We found a significant effect of the geographical distance on the spatial turnover component for the historical and current periods. In addition, the nestedness component was the main contributor to beta diversity, which indicated one large protected area should be established in Poyang Lake and the Ganjiang River Basin with higher species richness. These results indicated that fish biodiversity declined in the current period likely caused by anthropogenic habitat alteration and other threatened factors. Therefore, we suggest that the habitat reconstruction and biodiversity conservation for fish have become imperative in this basin, and a complete management plan should be carried out.

13.
Ecol Evol ; 9(11): 6353-6365, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31236226

RESUMO

Poyang Lake plays a significant role in maintaining and replenishing the macrozoobenthos biodiversity in the middle Yangtze River. However, due to human activities and natural factors, the habitat of Poyang Lake has been seriously degraded, resulting in a decline in macrozoobenthos biodiversity. Here, we analyzed the effect of human activity and environmental elements change on the diversity of macrozoobenthos based on a systematic investigation of Poyang Lake Basin in 2016-2017. The current species richness, density, and biomass of macrozoobenthos were lower than those in the historical period. At the same time, the community structure of the macrozoobenthos assemblage exhibits significant temporal and spatial differences. In addition, the spatial turnover component was the main contribution to beta diversity, which indicated that a number of protected areas would be necessary to conserve the biodiversity of macrozoobenthos. Water depth, dissolved oxygen, water velocity, and chlorophyll-a were significantly correlated with macrozoobenthos distributions and assemblage structure based on RDA. These results indicated that human activities have seriously destroyed the macrozoobenthos habitat and led to the decline in macrozoobenthos diversity. Therefore, habitat restoration and the conservation of macrozoobenthos have become urgent in Poyang Lake Basin, and an integrated management plan should be developed and effectively implemented.

14.
Int J Biol Macromol ; 133: 522-528, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31009691

RESUMO

Herein, we described the complete mitochondrial genome ('mitogenome') of the Chinese land snail Cyclophorus martensianus, which is the first published mitogenome for the caenogastropod family Cyclophoridae. This mitogenome is 15,308 bp long consisting of 37 genes: 13 protein-coding genes (PCGs), 22 tRNA genes and two rRNA genes. The A + T content (69.6%) is distinctly higher than the GC content (30.4%). Most PCGs start with ATN as initiation codons, and all PCGs have the conventional stop codons TAA and TAG. Overall, the biochemical properties and gene order of the cyclophorid mitogenome are very similar to those of other documented caenogastropod mitogenomes. We corroborate the findings of earlier studies that mitochondrial gene order is rather conserved among caenogastropods. Caenogastropoda are the taxonomically, morpho-anatomically and ecologically most diverse group of living gastropods comprising lineages inhabiting marine, freshwater, and terrestrial environments. Traditionally, the three most speciose groups of non-marine caenogastropods have all been placed in a single group, the Architaenioglossa. This group contains two freshwater lineages, the Viviparoidea and Ampullaroidea, and the terrestrial Cyclophoroidea. However, architaenioglossan relationships have remained controversial with several morphology-based on molecular phylogenetic analyses supporting contradicting phylogenetic hypotheses. In order to more robustly resolve the relationships among the Architaenioglossa, we have performed phylogenetic analyses of caenogastropod mitogenomes including the new mitogenome of Cyclophorus martensianus. Our phylogenetic reconstructions are based on the amino acid sequences of all protein-coding genes and consistently recovered Architaenioglossa as non-monophyletic.


Assuntos
Genoma Mitocondrial/genética , Filogenia , Caramujos/genética , Animais , Sequência de Bases , Evolução Molecular , Ordem dos Genes/genética , RNA Ribossômico/genética , RNA de Transferência/genética , Análise de Sequência
15.
Mol Phylogenet Evol ; 135: 177-184, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30858078

RESUMO

Stylommatophora is a main clade of Gastropoda that encompasses approximately 112 gastropod families and may exceed a total of 30,000 species. Twenty-four complete stylommatophoran mitogenomes have been sequenced to date, yet our understanding of mitochondrial evolution in stylommatophorans is still in its infancy. To further expand the set of available mitogenomes, we sequenced the mitogenome of Meghimatium bilineatum (Arionoidea: Philomycidae), a widespread land slug in East Asia. This is the first report on a mitogenome of the superfamily Arionoidea, and indeed on a terrestrial slug. The mitogenome of Meghimatium bilineatum comprises 13,972 bp and exhibits a novel, highly distinctive gene arrangement among the Stylommatophora. Phylogenetic reconstructions based on the sequences of all protein-coding genes consistently recovered Meghimatium bilineatum as sister-group of the Succineidae. A phylogenetic reconstruction based on gene order, however, suggested a highly divergent tree topology, which is less credible when taking into account prior knowledge of stylommatophoran relationships. Our CREx (Common interval Rearrangement Explorer) analysis suggested that three successive events of tandem duplication random loss (TDRL) best explain the evolutionary process of gene order rearrangement in Meghimatium bilineatum from an ancestral stylommatophoran mitogenome. The present example offers new insights into the mechanisms of mitogenome rearrangements in gastropods at large and into the usefulness of mitogenomic gene order as a phylogenetic marker.


Assuntos
Gastrópodes/genética , Rearranjo Gênico , Genoma Mitocondrial , Animais , Sequência de Bases , Mapeamento Cromossômico , Extremo Oriente , Ordem dos Genes , Mitocôndrias/genética , Filogenia
16.
Zookeys ; (817): 73-93, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30686923

RESUMO

The Luoxiao Mountains play an important role in maintaining and supplementing the fish diversity of the Yangtze River Basin, which is also a biodiversity hotspot in China. However, fish biodiversity has declined rapidly in this area as the result of human activities and the consequent environmental changes. Beta diversity was a key concept for understanding the ecosystem function and biodiversity conservation. Beta diversity patterns are evaluated and important information provided for protection and management of fish biodiversity in the Luoxiao Mountains. The results showed that the spatial turnover component was the main contributor to beta diversity of Hemiramphidae, Amblycipitidae, Catostomidae, Clariidae, Balitoridae and Percichthyidae in the Luoxiao Mountains, which indicated that a number of protected areas would be necessary to conserve fish biodiversity and that these families would need conservation measures. Most protected areas are currently limited to some regions; therefore, in order to protect fish diversity, conservation efforts must target an increase in the number of protected areas which should be spread across each of the regions.

17.
Zookeys ; (812): 23-46, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30636909

RESUMO

The Yangtze River basin is one of the most species-rich regions for freshwater mussels on Earth, but is gravely threatened by anthropogenic activities. However, conservation planning and management of mussel species has been hindered by a number of taxonomic uncertainties. In order to clarify the taxonomic status and phylogenetic position of these species, mitochondrial genomes of four species (Acuticostachinensis, Schistodesmuslampreyanus, Cuneopsisheudei and Cuneopsiscapitatus) were generated and analyzed along with data from 43 other mitogenomes. The complete F-type mitogenomes of A.chinensis, S.lampreyanus, C.heudei, and C.capitatus are 15652 bp, 15855 bp, 15892 bp, and 15844 bp, respectively, and all four F-type mitogenomes have the same pattern of gene arrangement. ML and BI trees based on the mitogenome dataset are completely congruent, and indicate that the included Unionidae belong to three subfamilies with high bootstrap and posterior probabilities, i.e., Unioninae (Aculamprotula, Cuneopsis, Nodularia, and Schistodesmus), Anodontinae (Cristaria, Arconaia, Acuticosta, Lanceolaria, Anemina, and Sinoanodonta), and Gonideinae (Ptychorhynchus, Solenaia, Lamprotula, and Sinohyriopsis). Results also indicate that A.chinensis has affinities with Arconaialanceolata and Lanceolariagrayii and is a member of the subfamily Anodontinae.

18.
Ecol Evol ; 9(24): 14142-14153, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31938509

RESUMO

Freshwater mussels provide important functions and services for aquatic ecosystems, but populations of many species have been extirpated. Information on biodiversity plays an important role in the conservation and management of freshwater mussels. The Xin River Basin is a biodiversity hotspot for freshwater mussels in China, with more than 43 species known, but populations of which are decreasing. Here, we quantify the diversity of freshwater mussels in the middle and lower reaches of the Xin River Basin and study the correlation of habitat characteristics and freshwater mussel diversity. Compared to the historical period, the number of species, density, and biomass of freshwater mussels decreased 33%, 83%, and 82% in the current period, respectively. Fifty two percent of recorded species were empty shells, and 14 native freshwater mussels were not found in the study area. Four species are currently listed as vulnerable species using IUCN criteria and their global status. The assemblage structure of freshwater mussels exhibits significant spatial differences, and there was a correlation with substrate and physicochemical parameters. The main tributary of the Xin River with higher freshwater mussel diversity should be established as one large protected area because the nestedness component was the main pattern of beta diversity. These results indicated freshwater mussel diversity was declining rapidly, which can help focus conservation effort for freshwater mussel biodiversity.

19.
Mitochondrial DNA B Resour ; 4(2): 2861-2862, 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-33365763

RESUMO

Radix plicatula is broadly distributed in China, as well as Russia. It is one of the intermediate hosts of Fasciola species which leads to the spread of fascioliasis. Here, we first described the complete mitochondrial genome of R. plicatula. The mitogenome is 13,751 bp in length, containing 13 protein-coding genes, 22 tRNA genes, and 2 rRNA genes. The contents of each base are 30.7% A, 39.6% T, 15.7% G, and 13.9% C. The sequence is AT rich (70.3%). Mitochondrial phylogenomic analysis showed that R. plicatula is close to R. auricularia.

20.
Mol Phylogenet Evol ; 130: 45-59, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30308278

RESUMO

The Yangtze River Basin in China is one of the global hotspots of freshwater mussel (order Unionida) diversity with 68 nominal species. Few studies have tested the validity of these nominal species. Some taxa from the Yangtze unionid fauna have not been adequately examined using molecular data and well-positioned phylogenetically with respect to the global Unionida. We evaluated species boundaries of Chinese freshwater mussels, and disentangled their phylogenetic relationships within the context of the global freshwater mussels based on the multi-locus data and complete mitochondrial genomes. Moreover, we produced the time-calibrated phylogeny of Unionida and explored patterns of diversification. COI barcode data suggested the existence of 41 phylogenetic distinct species from our sampled 40 nominal taxa inhabiting the middle and lower reaches of the Yangtze River. Maximum likelihood and Bayesian inference analyses on three loci (COI, 16S, and 28S) and complete mitochondrial genomes showed that the subfamily Unioninae sensu stricto was paraphyletic, and the subfamily Anodontinae should be subsumed under Unioninae. In addition, we described two new tribes (Aculamprotulini tribe nov. and Lepidodesmini tribe nov.) in the subfamily Unioninae and one new genus (Parvasolenaiagen. nov.) in the subfamily Gonideinae. Molecular dating analysis suggested freshwater mussels diversified at 346.1 Mya (HPD = 286.6-409.9). The global diversification rate for Unionida was estimated to be 0.025 species/Myr. Our study found only a single well-supported rate shift in Unionida diversification, occurring at the base of the subfamily Ambleminae. The evolution of active host-attraction may have triggered the burst of speciation in Ambleminae, and the environment and geography of the Mississippi River Basin likely sustained this radiation.


Assuntos
Bivalves/classificação , Filogenia , Animais , Teorema de Bayes , Bivalves/genética , China , Complexo IV da Cadeia de Transporte de Elétrons/genética , Água Doce , Variação Genética , Genoma Mitocondrial/genética , RNA Ribossômico/genética , Especificidade da Espécie
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