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In the present paper, the phylogeographies of two monogenean species, Pseudokuhnia minor and Kuhnia scombri, on the same species of host, Scomber japonicus, were studied. Fragments of the mitochondrial cytochrome c oxidase subunit 1 gene were sequenced for 264 individuals of P. minor and 224 individuals of K. scombri collected from 10 localities along the coast of China. Genetic diversity of K. scombri was higher than that of P. minor, which may imply that P. minor has a lower evolution rate and/or is a younger species. The neighbour-joining (NJ) trees of both parasites were comprised of two clades without association to sample sites, which is the signature of remixing populations following past division. Analyses of molecular variance and pairwise fixation index revealed different genetic structures for the populations of these two closely related species along the coast of China: P. minor without significant genetic structure, while K. scombri has some genetic differentiation. Both neutrality tests and mismatch distribution suggested that the populations of these two species of parasites experienced population expansion in the late Pleistocene era due to the glacial–interglacial cycles induced by climatic oscillations. [ABSTRACT FROM AUTHOR]

In this article, we examined the influences of the polycultured potential hosts on monogenean seasonality and the possible linkage between the infestations on different species of hosts and host phylogeny. The seasonality of Diplectanum grouperi , the dominant species, on wild versus cultured groupers, Epinephelus spp., was analyzed in Daya Bay, South China Sea, between April 2008 and January 2009. The prevalence, mean intensity, abundance, and variance/mean ratio were calculated for each species of host under polycultured and wild conditions. Except for the overall prevalence, which was slightly higher in autumn than that in summer under wild conditions, the mean intensity and variance were highest in summer, decreasing slightly in autumn to lowest levels in winter or spring. The infection level (prevalence, mean intensity, and abundance) was correlated with changes in water temperature during the sampling period, with a peak in summer, with the exception of E. awoara in autumn under wild conditions. The prevalence, intensity, and mean intensity of D. grouperi on Epinephelus spp. in the wild were much lower than those in experimental (mixed species) culture ponds. The correlation between the molecular phylogeny of 5 species of Epinephelus and the dendrogram based on the susceptibility to D. grouperi was not significant, which infers that variable susceptibilities of these Epinephelus species cannot be revealed by phylogenetic relationships determined from mitochondrial 16S rDNA and Cyt b gene sequences. [ABSTRACT FROM AUTHOR]

Abstract: Population genetic structure and historical demography of grey mullet, Mugil cephalus, along the coast of China were examined with a 389-bp segment of mtDNA control region. In total, 117 samples were collected from seven locations and 77 haplotypes were obtained. No haplotype was concurrently presented in all the samples, and samples in Southern and Northern regions had distinctly different haplotypes. Sorting of the data cladistically into phylogenetic trees indicated that these haplotypes can be divided into two main clades. Analysis of molecular variance (AMOVA) indicated significant genetic differentiation among subpopulations in different regions (φ CT =0.9505, p <0.01). The average pairwise differences and φ ST values (0.8943–0.9464) between regional populations were significant. The net Tumura and Nei genetic distance (0.5577±0.1421) between the two groups was large. The deep and unique divergence between the two groups suggested that each group is likely to represent a distinct species. In contrast to the great genetic divergence on a broad scale, small but significant population subdivisions at a less spatial scale were also detected both in Southern and Northern regions, which support the conclusion that M. cephalus has limited dispersal potential. High haplotype diversity (h =0.8716±0.1462) and low nucleotide diversity (π =0.0046±0.0030) were found among the three Northern samples. Among the four Southern samples, however, extraordinarily high levels of both haplotype diversity (h =0.9886±0.0057) and nucleotide diversity (π =0.0425±0.0212) were detected. The different polymorphisms suggest an apparent distinguishing demographic history between regionally Southern and Northern populations, though mismatch distribution analyses and neutrality tests implied a late Pleistocene population expansion of both Northern and Southern populations. [Copyright &y& Elsevier]

China's Belt and Road Initiative is the world's largest infrastructure development project aimed at linking Europe and East Africa with Asia. Port infrastructure development associated with the maritime component of China's Belt and Road Initiative (mBRI) could have trans -boundary environmental impacts. These impacts are likely to affect key coastal marine habitats (coral reefs, mangroves, seagrasses and saltmarshes) and threatened marine species. We used spatial analyses to quantify the potential impacts of ports and subsequent increased shipping traffic associated with the mBRI for key habitats and species. Significant areas of individual countries coastal marine habitats could be affected by port development. Over 400 threatened marine species, including mammals, could be affected by port infrastructure, while over 200 threatened species are at risk from an increase in shipping traffic and noise pollution. A project of this magnitude provides an opportunity for a central governing body to develop and implement an overarching environmental framework and policy that mitigates risks to biodiversity. • The Belt and Road Initiative is the world's largest infrastructure development project. • Key coastal marine habitats and threatened marine species are likely to be impacted. • We assess the potential impacts of port expansion and increased shipping. • International coordination is needed to mitigate risks to biodiversity. [ABSTRACT FROM AUTHOR]

Abstract: In the present study, we examined the phylogeographical pattern of the monogenean, Mazocraeoides gonialosae, which parasitises the dotted gizzard shad (Konosirus punctatus) along the coast of China. Fragments of 756bp of the mitochondrial cytochrome c oxidase subunit I gene were sequenced for 147 individuals from seven localities along the coast of China. Phylogenetic analysis revealed no significant genealogical clades of samples corresponding to sampling localities. Analyses of molecular variance and pairwise F ST suggested a high rate of gene flow and the lack of a predictable genetic structure between different populations of this parasite. Both neutrality tests and mismatch distribution analyses indicated a recent population expansion in M. gonialosae after the last glacial maximum. Gradually decreasing genetic diversity in more northerly populations implied a historical south-to-north expansion of this parasite. Dispersal of eggs and larvae with ocean currents was considered to be associated with the genetic homogeneity of this species. The limited time to accumulate genetic variation after the last glacial maximum may also account in part for the lack of phylogeographical structure in the studied region. [Copyright &y& Elsevier]