In metropolitan regions, the change in the strength of "flows" between a core city and surrounding cities re-flects the range of the core city's influence, while the gravity between core city and other c...In metropolitan regions, the change in the strength of "flows" between a core city and surrounding cities re-flects the range of the core city's influence, while the gravity between core city and other cities reflects the strength of potential relation between them. This article firstly attempts to delimit the boundary of metropolitan regions with the two dimensions measure combining "flows" and gravitation. The former is measured through the flow of people be-tween the core city and surrounding cities, and the latter is measured through both population and gross domestic products (GDP) of the core city and surrounding cities. The hierarchy of the cities within a metropolitan region is classified in order to emphasize the roles of the cities belonging to the metropolitan regions, different from the general way through population scale and administrative level, and is typical in China. This paper uses the Shanghai metropolitan region as a research case, determining boundary of this metropolitan region clearly and classifying hierarchy of the cities within the region. The final results are significantly different to previous work, even overthrowing the traditional system of urban hierarchy partly. It is helpful to highlight the function of cities in organizing the regional economy, the level structure of metropolitan regions, and each city's relative importance in a metropolitan region, which can be taken as scientific basis for planning integrated regions or urban systems.展开更多
Integrative data from plastid and nuclear loci are increasingly utilized to resolve species boundaries and phylogenetic relationships within major angiosperm clades.Debregeasia(Urticaceae),an economically important ge...Integrative data from plastid and nuclear loci are increasingly utilized to resolve species boundaries and phylogenetic relationships within major angiosperm clades.Debregeasia(Urticaceae),an economically important genus,presents challenges in species delimitation due to its overlapping morphological traits and unstable taxonomic assignments.Here,we analyzed 14 morphological traits and generated 12 data matrices from the plastomes and nrDNA using genome skimming from the nine recognized morphospecies to clarify species boundaries and assess barcode performance in Debregeasia.We also used a universal set of 353 nuclear genes to explore reticulate evolution and biogeographic history of Debregeasia.Plastomes of Debregeasia exhibited the typical quadripartite structure with conserved gene content and marginal independent variations in the SC/IR boundary at inter-and intra-specific levels.Three Debregeasia species were non-monophyletic and could not be discerned by any barcode;however,ultra-barcodes identified the remaining six(67%),outperforming standard barcodes(56%).Our phylogenetic analyses placed Debregeasia wallichiana outside the genus and suggested six monophyletic clades in Debregeasia,although the placement between Debregeasia hekouensis and Debregeasia libera varied.There was extensive trait overlap in key morphologically diagnostic characters,with reticulation analysis showing potentially pervasive hybridization,likely influenced by speciation patterns and overlaps between species ranges.We inferred that Debregeasia crown diversification began at ca.12.82 Ma(95%HPD:11.54-14.63 Ma)in the mid-Miocene within Australia,followed by vicariance and later longdistance dispersal,mainly out of southern China.Our findings highlight the utility of genomic data with integrative lines of evidence to refine species delimitation and explore evolutionary relationships in complex plant lineages.展开更多
The Ashy-headed Laughingthrush (Argya cinereifrons), a species endemic to Sri Lanka, has been historically considered a laughingthrush in the genus Garrulax. However, based on phylogenetic evidence, recent studies hav...The Ashy-headed Laughingthrush (Argya cinereifrons), a species endemic to Sri Lanka, has been historically considered a laughingthrush in the genus Garrulax. However, based on phylogenetic evidence, recent studies have suggested a new classification for the species under the genus Argya (true babblers). Despite the genetic signal showing affinity to true babblers Argya, as its common name suggests, the Ashy-headed Laughingthrush (AHLT) shows remarkable morphological similarities to other laughingthrushes of the Indo-Himalayan region. Here we attempted to address this incongruence in phenotypic and phylogenetic signals in this species by reconstructing the molecular phylogeny of babblers and comparing that with the key morphological, plumage, and vocal features of the two concerned groups. We hypothesized that the convergence of phenotype and vocalization of Garrulax in the wet evergreen forests of the Indian mainland and AHLT in the wet tropical rainforests of southern Sri Lanka has historically confused the taxonomists. The phylogenetic relationships were reconstructed using Bayesian inference using four mitochondrial and seven nuclear gene regions. The molecular phylogenetic tree placed the AHLT with India's Large Grey Babbler (A. malcolmi) as the sister taxon within the genus Argya. The hierarchical clustering based on body size, shape, plumage colour, and vocal properties resulted in the inconsistent placement of ALTH with babblers or laughingthrushes. Therefore, an incongruence in phenotype and genotype is observed. Our findings show that the convergent patterns of phenotypic evolution can confuse both historic and recent taxonomic delimitations in highly divergent groups such as Asian babblers.展开更多
Species are not only the fundamental units of taxonomy but also the basic units of pest management.Insects of Conogethes are important agricultural and forestry pests.However,species boundaries within Conogethes often...Species are not only the fundamental units of taxonomy but also the basic units of pest management.Insects of Conogethes are important agricultural and forestry pests.However,species boundaries within Conogethes often appear obscure.In the present study,we reevaluated the species status of Conogethes by applying three species delimitation approaches based on the mitochondrial DNA sequences,with particular emphasis on the yellow peach moth C.punctiferalis(Guenée,1854).We first optimized species delimitation and inter-species genetic divergence threshold using a DNA barcoding dataset.The results revealed that several nominal species of Conogethes species harbored deeply diverged mitochondrial lineages which were recognized as independent species by the species delimitation methods.The p-distance between the delimited putative species ranged from 0.0159 to 0.1321 with a mean of 0.0841.Then we refined the species status of C.punctiferalis using the smallest interspecific distance threshold based on a geographically comprehensive population-scale dataset.This procedure narrowed the species concept of C.punctiferalis to a genetically coherent unit.Further investigation of its intraspecific divergence in the geographic context revealed that the refined C.punctiferalis was still widely distributed with the same or highly similar mitochondrial haplotypes occurring across South and East Asia.展开更多
The genus Callistoctopus comprises 13 species,and has been reported mostly in the Western Pacific Ocean.Here,we described three new species from China,Ca.paucilamellus sp.nov.,Ca.sparsus sp.nov.,and Ca.gracilis sp.nov...The genus Callistoctopus comprises 13 species,and has been reported mostly in the Western Pacific Ocean.Here,we described three new species from China,Ca.paucilamellus sp.nov.,Ca.sparsus sp.nov.,and Ca.gracilis sp.nov.,based on morphometric and meristic characteristics.The diagnoses,descriptions and detailed morphometric data are provided for each species.The cytochrome c oxidase I(COI)genes of the three new species are sequenced,and compared with related species and analyzed for their systematic positions.Both phylogenetic trees constructed using three mitochondrial genes(12S rRNA,16S rRNA,COI)and one nuclear gene(Rhodopsin)revealed that our new species formed into two distinct clades with strong support values.One clade included Ca.gracilis sp.nov.,Ca.sp.1,Ca.xiaohongxu,Ca.tenuipes and Ca.paucilamellus sp.nov.,which clustered together.The other clade showed that Ca.sparsus sp.nov.was closely related to Ca.sp.2 and Ca.sp.3.Ca.luteus and Ca.macropus were located at the base of the Callistoctopus group.Based on our integrative studies,both morphological and molecular evidence suggested strongly that O.minor is more likely to be classified as a species of Callistoctopus.Morphological comparisons were made between the three new species and related taxa,which could be recognized based on the 7-8 gill lamellae of each demibranch,numerous small black spots on the subdermal layer of the arms,and an elongated body.展开更多
The seismic hazard of research area is evaluated by probabilistic analysis method for three different seismic statis-tical zone scenarios. The influence of uncertainty in seismic statistical zone delimiting on the eva...The seismic hazard of research area is evaluated by probabilistic analysis method for three different seismic statis-tical zone scenarios. The influence of uncertainty in seismic statistical zone delimiting on the evaluation result is discussed too. It can be seen that for those local sites along zone's border or within areas with vast change of upper bound magnitude among different scenarios the influence on seismic hazard result should not be neglected.展开更多
This paper provides an overview and a tutorial of the BPP program, which is a Bayesian MCMC program for analyzing multi-locus genomic sequence data under the multispecies coalescent model. An example dataset of five n...This paper provides an overview and a tutorial of the BPP program, which is a Bayesian MCMC program for analyzing multi-locus genomic sequence data under the multispecies coalescent model. An example dataset of five nuclear loci from the East Asian brown frogs is used to illustrate four different analyses, including estimation of species divergence times and population size parameters under the multispecies coalescent model on a fixed species phylogeny （A00）, species tree estimation when the assignment and species delimitation are fixed （A01）, species delimitation using a fixed guide tree （A10）, and joint species delimitation and species-tree estimation or unguided species delimitation （A11）. For the joint analysis （A11）, two new priors are introduced, which assign uniform probabilities for the different numbers of delimited species, which may be useful when assignment, species delimitation, and species phylogeny are all inferred in one joint analysis. The paper ends with a discussion of the assumptions, the strengths and weaknesses of the BPP analysis [Current Zoology 61 （5）： 854-865, 2015].展开更多
DNA-based approaches to systematics have changed dramatically during the last two decades with the rise of DNA barcoding methods and newer multi-locus methods for species delimitation. During the last half-decade, par...DNA-based approaches to systematics have changed dramatically during the last two decades with the rise of DNA barcoding methods and newer multi-locus methods for species delimitation. During the last half-decade, partly driven by the new sequencing technologies, the focus has shifted to multi-locus sequence data and the identification of species within the frame-work of the multi-species coalescent （MSC）. In this paper, I discuss model-based Bayesian methods for species delimitation that have been developed in recent years using the MSC. Several approximate methods for species delimitation （and their limitations） are also discussed. Explicit species delimitation models have the advantage of clarifying more precisely what is being delimited and what assumptions we are making in doing so. Moreover, the methods can be very powerful when applied to large multi-locus datasets and thus take full advantage of data generated using today＇s technologies [Current Zoology 61 （5）： 846-853,2015].展开更多
Geological anomaly is a geological body or geological body combination different from its surroundings in composition, structure, or genetic sequence. If there is a value (value interval ) that works as a valve repres...Geological anomaly is a geological body or geological body combination different from its surroundings in composition, structure, or genetic sequence. If there is a value (value interval ) that works as a valve representing the background field, exceeding or lower than the valve value,it is called a geological anomaly. Geological anomalies can be divided into high geological anomaly and low geological anomaly .The former shows the area that is more complex in composition, Structure or genetic sequence than its surroundings; while the latter just gives an opposite indication, i. e. much simpler. According to their distribution and delimitation markers, geological anomalies can be classified into (1)global geological anomaly; (2)regional geological anomaly; (3) local geological anomaly; (4) minor geological anomaly and (5)micro-geological anomaly .The methods for delimiting geological anomalies include (1)crustal elevation-subsidence coefficieat (G value ) determination; (2) geological complex coefficient (C value ) determination; (3) entropy (H value ) determination; (4) geological similarity coefficient (S value ) determination and (5 ) geological correlation coefficient (R value ) determination. As the result of the movements of Eurasian, Pacific and Indian Plates, the Chinese geological anomalies, including 11 regional ones and 32 main local ones, most Paleozoic in age, are distributed in strip on the margin or the outer and inner folded zones in the east and west arcs of the block symmetric arc tectonic system (BSATS), which controls the distribution of various minerals in China. Thus, geological anomaly theory is of great significance in searching for large, super-large and very large ore deposits.展开更多
Objective:To examine and study the morphology,epidemiology,and molecular phylogeny of Anisakis larvae in blue mackerel[Scomber australasicus(Cuvier,1832)]and Indian mackerel[Rastrelliger kanagurta(Cuvier,1816)]using l...Objective:To examine and study the morphology,epidemiology,and molecular phylogeny of Anisakis larvae in blue mackerel[Scomber australasicus(Cuvier,1832)]and Indian mackerel[Rastrelliger kanagurta(Cuvier,1816)]using light microscope,scanning electron microscope,molecular phylogeny,and species delimitation methods for confirmation and investigation of Anisakis species and their evolutionary relationship.Methods:A total of 90 fish(45 per species)were purchased from a department store in Chiang Mai,Thailand.Anisakis samples were investigated for morphological characteristics using light and scanning electron microscopes.Molecular phylogeny and species delimitation methods based on the cox2 gene were performed.Results:The prevalence,mean intensity(Mean±SEM),and mean abundance of Anisakis larvae(Mean±SEM)in blue mackerel were 77.78%,6.74±1.320,and 5.24±1.107,respectively,and in Indian mackerel,these values were 13.33%,2.50±0.764,and 0.33±0.159,respectively.Scanning electron microscopy showed the detail of morphological characteristics and provided the different shapes of mucron and excretory pores in Anisakis larvae congruent with the phylogenetic tree.The species tree was congruent with the phylogenetic tree.Conclusions:The prevalence,mean intensity,and mean abundance of Anisakis larvae were higher in blue mackerel.To the best of our knowledge,this is the first time that Anisakis pegreffii was found in blue mackerel in Thailand.The phylogenetic tree also supported the morphological data of Anisakis larvae.However,species delimitation based on cox2 revealed 1-3 possible cryptic species in this genus.Anisakis spp.contamination of fish products is unpleasant and a health concern considering human infection with larvae(anisakiasis)arises.展开更多
基金Under the auspices of Shanghai Foundation Item for Philosophy and Social Sciences (No 2005BCK004)Research Center on Metropolitan Regions of China (No RCMRC 07006)
文摘In metropolitan regions, the change in the strength of "flows" between a core city and surrounding cities re-flects the range of the core city's influence, while the gravity between core city and other cities reflects the strength of potential relation between them. This article firstly attempts to delimit the boundary of metropolitan regions with the two dimensions measure combining "flows" and gravitation. The former is measured through the flow of people be-tween the core city and surrounding cities, and the latter is measured through both population and gross domestic products (GDP) of the core city and surrounding cities. The hierarchy of the cities within a metropolitan region is classified in order to emphasize the roles of the cities belonging to the metropolitan regions, different from the general way through population scale and administrative level, and is typical in China. This paper uses the Shanghai metropolitan region as a research case, determining boundary of this metropolitan region clearly and classifying hierarchy of the cities within the region. The final results are significantly different to previous work, even overthrowing the traditional system of urban hierarchy partly. It is helpful to highlight the function of cities in organizing the regional economy, the level structure of metropolitan regions, and each city's relative importance in a metropolitan region, which can be taken as scientific basis for planning integrated regions or urban systems.
基金funded by the National Natural Science Foundation of China(42171071,42211540718)Key Research Program of Frontier Sciences,CAS(ZDBS-LY-7001)+3 种基金Yunnan Fundamental Research Projects(202401AT070190,202201BC070001)Top-notch Young Talents Project of Yunnan Provincial“Ten Thousand Talents Program”(YNWR-QNBJ-2018-146,YNWR-QNBJ-2020-293)CAS“Light of West China”Programsupported by the China Scholarship Council(202304910135 and 202304910138)for a one-year study at the University of Toronto.
文摘Integrative data from plastid and nuclear loci are increasingly utilized to resolve species boundaries and phylogenetic relationships within major angiosperm clades.Debregeasia(Urticaceae),an economically important genus,presents challenges in species delimitation due to its overlapping morphological traits and unstable taxonomic assignments.Here,we analyzed 14 morphological traits and generated 12 data matrices from the plastomes and nrDNA using genome skimming from the nine recognized morphospecies to clarify species boundaries and assess barcode performance in Debregeasia.We also used a universal set of 353 nuclear genes to explore reticulate evolution and biogeographic history of Debregeasia.Plastomes of Debregeasia exhibited the typical quadripartite structure with conserved gene content and marginal independent variations in the SC/IR boundary at inter-and intra-specific levels.Three Debregeasia species were non-monophyletic and could not be discerned by any barcode;however,ultra-barcodes identified the remaining six(67%),outperforming standard barcodes(56%).Our phylogenetic analyses placed Debregeasia wallichiana outside the genus and suggested six monophyletic clades in Debregeasia,although the placement between Debregeasia hekouensis and Debregeasia libera varied.There was extensive trait overlap in key morphologically diagnostic characters,with reticulation analysis showing potentially pervasive hybridization,likely influenced by speciation patterns and overlaps between species ranges.We inferred that Debregeasia crown diversification began at ca.12.82 Ma(95%HPD:11.54-14.63 Ma)in the mid-Miocene within Australia,followed by vicariance and later longdistance dispersal,mainly out of southern China.Our findings highlight the utility of genomic data with integrative lines of evidence to refine species delimitation and explore evolutionary relationships in complex plant lineages.
基金funded by the University of Colombo Research Grants,Sri Lanka(AP/3/2012/CG/15 and AP/3/2017/CG/27).
文摘The Ashy-headed Laughingthrush (Argya cinereifrons), a species endemic to Sri Lanka, has been historically considered a laughingthrush in the genus Garrulax. However, based on phylogenetic evidence, recent studies have suggested a new classification for the species under the genus Argya (true babblers). Despite the genetic signal showing affinity to true babblers Argya, as its common name suggests, the Ashy-headed Laughingthrush (AHLT) shows remarkable morphological similarities to other laughingthrushes of the Indo-Himalayan region. Here we attempted to address this incongruence in phenotypic and phylogenetic signals in this species by reconstructing the molecular phylogeny of babblers and comparing that with the key morphological, plumage, and vocal features of the two concerned groups. We hypothesized that the convergence of phenotype and vocalization of Garrulax in the wet evergreen forests of the Indian mainland and AHLT in the wet tropical rainforests of southern Sri Lanka has historically confused the taxonomists. The phylogenetic relationships were reconstructed using Bayesian inference using four mitochondrial and seven nuclear gene regions. The molecular phylogenetic tree placed the AHLT with India's Large Grey Babbler (A. malcolmi) as the sister taxon within the genus Argya. The hierarchical clustering based on body size, shape, plumage colour, and vocal properties resulted in the inconsistent placement of ALTH with babblers or laughingthrushes. Therefore, an incongruence in phenotype and genotype is observed. Our findings show that the convergent patterns of phenotypic evolution can confuse both historic and recent taxonomic delimitations in highly divergent groups such as Asian babblers.
基金This study was supported by a starting fund from Hebei Agricultural University and the State Key Laboratory of North China Crop Improvement and Regulation(YJ2020028).
文摘Species are not only the fundamental units of taxonomy but also the basic units of pest management.Insects of Conogethes are important agricultural and forestry pests.However,species boundaries within Conogethes often appear obscure.In the present study,we reevaluated the species status of Conogethes by applying three species delimitation approaches based on the mitochondrial DNA sequences,with particular emphasis on the yellow peach moth C.punctiferalis(Guenée,1854).We first optimized species delimitation and inter-species genetic divergence threshold using a DNA barcoding dataset.The results revealed that several nominal species of Conogethes species harbored deeply diverged mitochondrial lineages which were recognized as independent species by the species delimitation methods.The p-distance between the delimited putative species ranged from 0.0159 to 0.1321 with a mean of 0.0841.Then we refined the species status of C.punctiferalis using the smallest interspecific distance threshold based on a geographically comprehensive population-scale dataset.This procedure narrowed the species concept of C.punctiferalis to a genetically coherent unit.Further investigation of its intraspecific divergence in the geographic context revealed that the refined C.punctiferalis was still widely distributed with the same or highly similar mitochondrial haplotypes occurring across South and East Asia.
基金supported by research grants from National Natural Science Foundation of China(32170536,31672257).
文摘The genus Callistoctopus comprises 13 species,and has been reported mostly in the Western Pacific Ocean.Here,we described three new species from China,Ca.paucilamellus sp.nov.,Ca.sparsus sp.nov.,and Ca.gracilis sp.nov.,based on morphometric and meristic characteristics.The diagnoses,descriptions and detailed morphometric data are provided for each species.The cytochrome c oxidase I(COI)genes of the three new species are sequenced,and compared with related species and analyzed for their systematic positions.Both phylogenetic trees constructed using three mitochondrial genes(12S rRNA,16S rRNA,COI)and one nuclear gene(Rhodopsin)revealed that our new species formed into two distinct clades with strong support values.One clade included Ca.gracilis sp.nov.,Ca.sp.1,Ca.xiaohongxu,Ca.tenuipes and Ca.paucilamellus sp.nov.,which clustered together.The other clade showed that Ca.sparsus sp.nov.was closely related to Ca.sp.2 and Ca.sp.3.Ca.luteus and Ca.macropus were located at the base of the Callistoctopus group.Based on our integrative studies,both morphological and molecular evidence suggested strongly that O.minor is more likely to be classified as a species of Callistoctopus.Morphological comparisons were made between the three new species and related taxa,which could be recognized based on the 7-8 gill lamellae of each demibranch,numerous small black spots on the subdermal layer of the arms,and an elongated body.
基金Chinese Joint Seismological Science Foundation (100110).
文摘The seismic hazard of research area is evaluated by probabilistic analysis method for three different seismic statis-tical zone scenarios. The influence of uncertainty in seismic statistical zone delimiting on the evaluation result is discussed too. It can be seen that for those local sites along zone's border or within areas with vast change of upper bound magnitude among different scenarios the influence on seismic hazard result should not be neglected.
文摘This paper provides an overview and a tutorial of the BPP program, which is a Bayesian MCMC program for analyzing multi-locus genomic sequence data under the multispecies coalescent model. An example dataset of five nuclear loci from the East Asian brown frogs is used to illustrate four different analyses, including estimation of species divergence times and population size parameters under the multispecies coalescent model on a fixed species phylogeny （A00）, species tree estimation when the assignment and species delimitation are fixed （A01）, species delimitation using a fixed guide tree （A10）, and joint species delimitation and species-tree estimation or unguided species delimitation （A11）. For the joint analysis （A11）, two new priors are introduced, which assign uniform probabilities for the different numbers of delimited species, which may be useful when assignment, species delimitation, and species phylogeny are all inferred in one joint analysis. The paper ends with a discussion of the assumptions, the strengths and weaknesses of the BPP analysis [Current Zoology 61 （5）： 854-865, 2015].
文摘DNA-based approaches to systematics have changed dramatically during the last two decades with the rise of DNA barcoding methods and newer multi-locus methods for species delimitation. During the last half-decade, partly driven by the new sequencing technologies, the focus has shifted to multi-locus sequence data and the identification of species within the frame-work of the multi-species coalescent （MSC）. In this paper, I discuss model-based Bayesian methods for species delimitation that have been developed in recent years using the MSC. Several approximate methods for species delimitation （and their limitations） are also discussed. Explicit species delimitation models have the advantage of clarifying more precisely what is being delimited and what assumptions we are making in doing so. Moreover, the methods can be very powerful when applied to large multi-locus datasets and thus take full advantage of data generated using today＇s technologies [Current Zoology 61 （5）： 846-853,2015].
文摘Geological anomaly is a geological body or geological body combination different from its surroundings in composition, structure, or genetic sequence. If there is a value (value interval ) that works as a valve representing the background field, exceeding or lower than the valve value,it is called a geological anomaly. Geological anomalies can be divided into high geological anomaly and low geological anomaly .The former shows the area that is more complex in composition, Structure or genetic sequence than its surroundings; while the latter just gives an opposite indication, i. e. much simpler. According to their distribution and delimitation markers, geological anomalies can be classified into (1)global geological anomaly; (2)regional geological anomaly; (3) local geological anomaly; (4) minor geological anomaly and (5)micro-geological anomaly .The methods for delimiting geological anomalies include (1)crustal elevation-subsidence coefficieat (G value ) determination; (2) geological complex coefficient (C value ) determination; (3) entropy (H value ) determination; (4) geological similarity coefficient (S value ) determination and (5 ) geological correlation coefficient (R value ) determination. As the result of the movements of Eurasian, Pacific and Indian Plates, the Chinese geological anomalies, including 11 regional ones and 32 main local ones, most Paleozoic in age, are distributed in strip on the margin or the outer and inner folded zones in the east and west arcs of the block symmetric arc tectonic system (BSATS), which controls the distribution of various minerals in China. Thus, geological anomaly theory is of great significance in searching for large, super-large and very large ore deposits.
文摘Objective:To examine and study the morphology,epidemiology,and molecular phylogeny of Anisakis larvae in blue mackerel[Scomber australasicus(Cuvier,1832)]and Indian mackerel[Rastrelliger kanagurta(Cuvier,1816)]using light microscope,scanning electron microscope,molecular phylogeny,and species delimitation methods for confirmation and investigation of Anisakis species and their evolutionary relationship.Methods:A total of 90 fish(45 per species)were purchased from a department store in Chiang Mai,Thailand.Anisakis samples were investigated for morphological characteristics using light and scanning electron microscopes.Molecular phylogeny and species delimitation methods based on the cox2 gene were performed.Results:The prevalence,mean intensity(Mean±SEM),and mean abundance of Anisakis larvae(Mean±SEM)in blue mackerel were 77.78%,6.74±1.320,and 5.24±1.107,respectively,and in Indian mackerel,these values were 13.33%,2.50±0.764,and 0.33±0.159,respectively.Scanning electron microscopy showed the detail of morphological characteristics and provided the different shapes of mucron and excretory pores in Anisakis larvae congruent with the phylogenetic tree.The species tree was congruent with the phylogenetic tree.Conclusions:The prevalence,mean intensity,and mean abundance of Anisakis larvae were higher in blue mackerel.To the best of our knowledge,this is the first time that Anisakis pegreffii was found in blue mackerel in Thailand.The phylogenetic tree also supported the morphological data of Anisakis larvae.However,species delimitation based on cox2 revealed 1-3 possible cryptic species in this genus.Anisakis spp.contamination of fish products is unpleasant and a health concern considering human infection with larvae(anisakiasis)arises.
