Abstract
The taxonomic status of the keeled back mullets (Teleostei: Mugilidae) has been reinvest... more Abstract The taxonomic status of the keeled back mullets (Teleostei: Mugilidae) has been reinvestigated. Two nominal mugilid species having keeled backs from East Asia: Mugil lauvergnii Eydoux & Souleyet, 1850 and Mugil affinis Günther, 1861 have been re-evaluated through examination of the holotypes and fresh specimens. Comparison of morphomeristic characters of the holotypes shows that both species are identical. Phylogenetic analysis based on mitochondrial cytochrome c oxidase 1 (CO1) confirmed morphological data by highlighting presence of a single clade from East Asia. Mugil lauvergnii (=Planiliza lauvergnii) is thus the sole keeled back mullet from East Asia and a senior synonym of Mugil affinis (=Planiliza affinis). The taxonomic status of two other keeled back mullets, Planiliza carinata and P. klunzingeri, is also contentious due to their similar morphology. Meristic and morphometric variation as well as sequence divergence between the two species are limited but phylogenetic analyses delineate well-supported clades consistent with biogeography and currently accepted taxonomy. Planiliza carinata and P. klunzingeri share a recent common ancestor in a Maximum Likelihood tree, with separate distribution ranges while P. lauvergnii formed a paraphyletic lineage. Based on present findings, we suggest maintenance of the taxonomic distinction of P. klunzingeri and P. carinata and discuss its evolutionary significance.
The phylogenetic relationships of cyprinid species from the Middle East and neighboring biogeogra... more The phylogenetic relationships of cyprinid species from the Middle East and neighboring biogeographical areas were investigated using cytochrome b sequence variation in order to test hypotheses that consider the Middle Eastern area as an important interchange area or a center of speciation for the freshwater fauna. A total of 62 cyprinid species were analyzed over the complete cytochrome b fragment (1140 bp); 28 belong to the Leuciscinae subfamily and 34 to the Cyprininae. All the Leuciscinae lineage fish recorded in the Middle East are also found in Europe, which was interpreted as an important Palearctic influence in the Middle Eastern ichthyofauna consistent with the Lago Mare dispersion. However, it has also been suggested that several Danube species have their origins in the Middle East. In contrast, the Cyprininae subfamily showed three highly divergent lineages, one shared with the Euro-Mediterranean area (Barbus/Luciobarbus genus) relict of the Lago Mare dispersion, one shared with Africa (Carasobarbus/Varicorhinus subgenus), and the third shared with Asia (Garra genus). Furthermore, clades observed in the phylogenetic reconstructions are not consistent with morphometric or karyological data and disagree with previous taxonomic assumptions. Lastly, the dispersion history in the Middle East of this subfamily appears much more complicated and ancient than that of the Leuciscinae. However, taking into account Cyprininae and Leuciscinae distribution, the Middle East appears more like an important interchange area for the freshwater ichtyofauna than a center of speciation.
FIGURE 11. Acanthopagrus datnia, synonymised specimens— A. BMNH 1858.8.15.3, 118 mm SL, Chrysophr... more FIGURE 11. Acanthopagrus datnia, synonymised specimens— A. BMNH 1858.8.15.3, 118 mm SL, Chrysophrys hasta of Günther (1859), one of the syntype, Bay of Bengal; Rightside, reversed (Photo: NHM, London). B. Uncatalogued specimen, 173 mm SL, Calcutta (= Kolkata), India, Bay of Bengal (as Acanthopagrus longispinnis in Iwatsuki 2013: 67) (Photo: S. K. Sen).
FIGURE 3. Maximum likelihood tree constructed using mitochondrial CO1 depicting phylogenetic rela... more FIGURE 3. Maximum likelihood tree constructed using mitochondrial CO1 depicting phylogenetic relationship among selected Acanthopagrus spp. including Acanthopagrus datnia and A. berda from Bay of Bengal, and Sparidentex hasta. Details of specimen data and GenBank accession numbers are provided in Table 1. Check images of some specimen in Fig. 8. Note—all Acanthopagrus datnia specimens with variable body shape (■, slender SL/BD>2.4, or O, deeper<2.4), and variable length of 2AS (above or below 21% SL) in one single clade.
American Scientific Research Journal for Engineering, Technology, and Sciences, 2016
On the purpose to study the genetic ecotoxicology of Sarotherodon melanotheron, the degree of con... more On the purpose to study the genetic ecotoxicology of Sarotherodon melanotheron, the degree of contamination due to two micropollutants (Polychlorinated biphenyls (PCBs) and Polybrominateddiphenyl ethers (PBDE)) on seven sites (Foundiougne, Kaolack, Missirah, Koular, HannBay and Niayes (1 and 2) was evaluated. Seven systems (ADH, AAT, IDHP, MDH, PGM, GPI and EST) were analyzed through the technical of enzymatic electrophoresis. The specimens and sediments used for the proportioning pollutants were sampled into 2009.The analysis of indicator PCBs was carried out by gaseous chromatography coupled to a detector with capture of electrons (GC-DCE). The analysis of the PBDE, was done by gaseous chromatography coupled to mass spectrometry high resolution (GC-MSHR). Highest concentrations of pollutants PCBs (19 ng/g) and PBDE (5 ng/g) were observed in Hann Bay. The analysis of allelic variability revealed an adaptive polymorphism at locus EST-14 and PGM at S. m. heudelotii; PGM at S. m. pal...
The flathead grey mullet species (Mugil cephalus L.) Vietnam is an euryhaline fish whose distribu... more The flathead grey mullet species (Mugil cephalus L.) Vietnam is an euryhaline fish whose distribution ranges from the North to the South. Currently, M. cephalus is facing the threat of overexploitation, and the number of individuals in most populations is declining fast. In order to conserve the species in Vietnam, it is necessary to evaluate its genetic diversity. Therefore, this study was carried out in Vietnam from August 2012 to June 2015. The results of our study provided the analysis for 12 locus microsatellites (SSR) from 70 mature individuals (standard length > 25 cm). The study also identified a total of 35 alleles for all loci studied, among which 10 loci were polymorphic. Average value of polymorphic information content (PIC) for each polymorphic marker was 0.2889 (0.0289 to 0.5918). Coefficient heterozygous gene Ho = 0.942; He = 0.517; Fst = 0.216; Fis = - 0.8211 (Fis < 0). The genetic relationship of 70 specimens or M. cephalus in Vietnam were divided in three mai...
Phylogenetic relationships among Greek populations of the chub, Leuciscus cephalus, were investig... more Phylogenetic relationships among Greek populations of the chub, Leuciscus cephalus, were investigated using 600 bp of the cytochrome b gene. The aim of this study was to test the assumption that the main difference in ichthyological composition between both sides of the Balkan Peninsula is directly linked to differences in the dispersion mechanisms used by fish in order to extend their distribution range. Phylogenetic and nested clade analyses clearly showed that populations in Greece are significantly differentiated. Greek populations were found to descend from three lineages in three geographical provinces: Western, Central, and Eastern Greece. The chub reached Western Greece at the beginning of the Pleistocene and Eastern Greece during the mid-Pleistocene. Chub dispersion occurred mainly by river confluence due to sea level lowering and river capture in Western Greece and sea dispersal with low-salinity conditions within the Aegean Sea in Eastern Greece. However, in Central Greece, the original mtDNA lineage has presumably been lost owing to a genetic introgression following a second invasion from the Danube during the final stage of the last glaciation. This study provides new elements for a better understanding of the composition of the contemporary ichthyofauna in Greece and highlights possible evolutionary mechanisms responsible for the high endemism rate in the Western Greek biogeographic province. 1999 Academic Press
The taxonomic status of the Bay of Bengal nominal sparid species Coius datnia Hamilton, 1822 and ... more The taxonomic status of the Bay of Bengal nominal sparid species Coius datnia Hamilton, 1822 and Acanthopagrus longispinnis (Valenciennes, 1830) are reviewed and investigated both morphologically and genetically. Because of inadequate description and no type specimen, Coius datnia has recently been considered to belong to Sparidentex, a genus without molarifom teeth. Critical examination of the original description and examination of specimens from the type locality and adjacent areas reveal that Coius datnia belongs to Acanthopagrus, a genus with an inner series of molars. Furthermore, examination of specimens previously recognized as Acanthopagrus longispinnis (Valenciennes 1830), and recent collection of fresh specimens from lower Ganges estuary in Bangladesh, show that morphological differences between Acanthopagrus datnia and A. longispinnis are minor, and they are genetically identical. The longer second anal-fin spine in A. longispinnis (>21% SL) is, in fact, a feature of ...
Mugil cephalus sensu lato is a globally distributed complex of cryptic species whose distribution... more Mugil cephalus sensu lato is a globally distributed complex of cryptic species whose distribution range and evolutionary history remains largely unknown. In the North West (NW) Pacific three species have been identified genetically among fish described morphologically as M. cephalus. Their distribution ranges are largely parapatric and has been proposed to mirror different thermal preferences. To date, few samples have been analyzed from South China Sea, which limits inferences on the evolutionary history of the species complex. We sampled fish identified morphologically as M. cephalus along Vietnamese shores and characterized them using the sequence polymorphism of two mitochondrial genes, the cytochrome oxidase I and cytochrome b. This demonstrated that all three species described in the NW Pacific are present in both northern and southern Vietnamese waters. Although the difference in species abundance reflects those observed in the NW Pacific, no phylogeographic pattern was revealed. In addition, no population structure was observed whatever the species or the distribution range considered, which indicates a significant level of gene flow that maintains genetic homogeneity of the three species. It is also conceivable that each species experienced a recent population expansion from a single ancestral population. Finally we suggest that if the cold waters of the NW Pacific present a physiologic challenge leading to the almost parapatric distribution of the three species, then it is likely that the warm surface temperatures of the South China Sea negate this barrier.
The interrelationships among mugilids (Mugiliformes: Mugilidae) remain highly debated. Using a mi... more The interrelationships among mugilids (Mugiliformes: Mugilidae) remain highly debated. Using a mitochondrial gene-based phylogeny as criterion, a revised classification with 25 genera in the Mugilidae has recently been proposed. However, phylogenetic relationships of major mitochondrial lineages remain unresolved and to gain a general acceptance the classification requires confirmation based on multilocus evidence and diagnostic morphological characters. Here, we construct a species-tree using twelve nuclear and three mitochondrial loci and infer the evolution of 71 morphological characters. Our multilocus phylogeny does not agree with previous morphology-based hypotheses for the relationships within Mugilidae, confirms the revised classification with 25 genera and further resolves their phylogenetic relationships. Using the well-resolved multilocus phylogeny as the criterion, we reclassify Mugilidae genera into three new subfamilies (Myxinae, Rhinomugilinae, and Cheloninae) and one...
Two new species and two new basin records of mahseers in the genera Tor and Neolissochilus are de... more Two new species and two new basin records of mahseers in the genera Tor and Neolissochilus are described from the upper Krong No and middle Đồng Nai drainages of the Langbiang Plateau in southern Vietnam. These new species and new records are known from streams and rivers in montane mixed pine and evergreen forests between 140 and 1112 m. Their populations are isolated in the Sre Pok River of the Mekong basin, the middle of the Đồng Nai basin, and the An Lão River. Both new species are differentiated from their congeners by a combination of the following characters: 23-24 lateral scales, 9-10 predorsal scales, 2/7 or 1/8 pelvic-fin rays, mouth position, median lobe of lower lip, rostral hood, colour in life and by divergent mitochondrial DNA. Tor mekongensis sp. nov. is differentiated from Tor dongnaiensis sp. nov. by the number of transverse scale rows (3/1/2 vs. 4/1/2), number of pelvic-fin rays (2/7 vs. 1/8), a blunt rostral hood vs. pointed, caudal-fin lobes that are equal vs. unequal, and by mitochondrial DNA (0.7% sequence divergence). Molecular evidence identifies both species as members of the genus Tor and distinct from all congeners sampled (uncorrected sequence divergences &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;1.9% for all Tor species for which homologous COI sequences are available). Tor sinensis is recorded in the Krong No and the Sre Pok rivers, further south of its known distribution. Polymorphism is described in Neolissochilus stracheyi with a Tor-like morph and a Neolissochilus-like morph.
Abstract
The taxonomic status of the keeled back mullets (Teleostei: Mugilidae) has been reinvest... more Abstract The taxonomic status of the keeled back mullets (Teleostei: Mugilidae) has been reinvestigated. Two nominal mugilid species having keeled backs from East Asia: Mugil lauvergnii Eydoux & Souleyet, 1850 and Mugil affinis Günther, 1861 have been re-evaluated through examination of the holotypes and fresh specimens. Comparison of morphomeristic characters of the holotypes shows that both species are identical. Phylogenetic analysis based on mitochondrial cytochrome c oxidase 1 (CO1) confirmed morphological data by highlighting presence of a single clade from East Asia. Mugil lauvergnii (=Planiliza lauvergnii) is thus the sole keeled back mullet from East Asia and a senior synonym of Mugil affinis (=Planiliza affinis). The taxonomic status of two other keeled back mullets, Planiliza carinata and P. klunzingeri, is also contentious due to their similar morphology. Meristic and morphometric variation as well as sequence divergence between the two species are limited but phylogenetic analyses delineate well-supported clades consistent with biogeography and currently accepted taxonomy. Planiliza carinata and P. klunzingeri share a recent common ancestor in a Maximum Likelihood tree, with separate distribution ranges while P. lauvergnii formed a paraphyletic lineage. Based on present findings, we suggest maintenance of the taxonomic distinction of P. klunzingeri and P. carinata and discuss its evolutionary significance.
The phylogenetic relationships of cyprinid species from the Middle East and neighboring biogeogra... more The phylogenetic relationships of cyprinid species from the Middle East and neighboring biogeographical areas were investigated using cytochrome b sequence variation in order to test hypotheses that consider the Middle Eastern area as an important interchange area or a center of speciation for the freshwater fauna. A total of 62 cyprinid species were analyzed over the complete cytochrome b fragment (1140 bp); 28 belong to the Leuciscinae subfamily and 34 to the Cyprininae. All the Leuciscinae lineage fish recorded in the Middle East are also found in Europe, which was interpreted as an important Palearctic influence in the Middle Eastern ichthyofauna consistent with the Lago Mare dispersion. However, it has also been suggested that several Danube species have their origins in the Middle East. In contrast, the Cyprininae subfamily showed three highly divergent lineages, one shared with the Euro-Mediterranean area (Barbus/Luciobarbus genus) relict of the Lago Mare dispersion, one shared with Africa (Carasobarbus/Varicorhinus subgenus), and the third shared with Asia (Garra genus). Furthermore, clades observed in the phylogenetic reconstructions are not consistent with morphometric or karyological data and disagree with previous taxonomic assumptions. Lastly, the dispersion history in the Middle East of this subfamily appears much more complicated and ancient than that of the Leuciscinae. However, taking into account Cyprininae and Leuciscinae distribution, the Middle East appears more like an important interchange area for the freshwater ichtyofauna than a center of speciation.
FIGURE 11. Acanthopagrus datnia, synonymised specimens— A. BMNH 1858.8.15.3, 118 mm SL, Chrysophr... more FIGURE 11. Acanthopagrus datnia, synonymised specimens— A. BMNH 1858.8.15.3, 118 mm SL, Chrysophrys hasta of Günther (1859), one of the syntype, Bay of Bengal; Rightside, reversed (Photo: NHM, London). B. Uncatalogued specimen, 173 mm SL, Calcutta (= Kolkata), India, Bay of Bengal (as Acanthopagrus longispinnis in Iwatsuki 2013: 67) (Photo: S. K. Sen).
FIGURE 3. Maximum likelihood tree constructed using mitochondrial CO1 depicting phylogenetic rela... more FIGURE 3. Maximum likelihood tree constructed using mitochondrial CO1 depicting phylogenetic relationship among selected Acanthopagrus spp. including Acanthopagrus datnia and A. berda from Bay of Bengal, and Sparidentex hasta. Details of specimen data and GenBank accession numbers are provided in Table 1. Check images of some specimen in Fig. 8. Note—all Acanthopagrus datnia specimens with variable body shape (■, slender SL/BD>2.4, or O, deeper<2.4), and variable length of 2AS (above or below 21% SL) in one single clade.
American Scientific Research Journal for Engineering, Technology, and Sciences, 2016
On the purpose to study the genetic ecotoxicology of Sarotherodon melanotheron, the degree of con... more On the purpose to study the genetic ecotoxicology of Sarotherodon melanotheron, the degree of contamination due to two micropollutants (Polychlorinated biphenyls (PCBs) and Polybrominateddiphenyl ethers (PBDE)) on seven sites (Foundiougne, Kaolack, Missirah, Koular, HannBay and Niayes (1 and 2) was evaluated. Seven systems (ADH, AAT, IDHP, MDH, PGM, GPI and EST) were analyzed through the technical of enzymatic electrophoresis. The specimens and sediments used for the proportioning pollutants were sampled into 2009.The analysis of indicator PCBs was carried out by gaseous chromatography coupled to a detector with capture of electrons (GC-DCE). The analysis of the PBDE, was done by gaseous chromatography coupled to mass spectrometry high resolution (GC-MSHR). Highest concentrations of pollutants PCBs (19 ng/g) and PBDE (5 ng/g) were observed in Hann Bay. The analysis of allelic variability revealed an adaptive polymorphism at locus EST-14 and PGM at S. m. heudelotii; PGM at S. m. pal...
The flathead grey mullet species (Mugil cephalus L.) Vietnam is an euryhaline fish whose distribu... more The flathead grey mullet species (Mugil cephalus L.) Vietnam is an euryhaline fish whose distribution ranges from the North to the South. Currently, M. cephalus is facing the threat of overexploitation, and the number of individuals in most populations is declining fast. In order to conserve the species in Vietnam, it is necessary to evaluate its genetic diversity. Therefore, this study was carried out in Vietnam from August 2012 to June 2015. The results of our study provided the analysis for 12 locus microsatellites (SSR) from 70 mature individuals (standard length > 25 cm). The study also identified a total of 35 alleles for all loci studied, among which 10 loci were polymorphic. Average value of polymorphic information content (PIC) for each polymorphic marker was 0.2889 (0.0289 to 0.5918). Coefficient heterozygous gene Ho = 0.942; He = 0.517; Fst = 0.216; Fis = - 0.8211 (Fis < 0). The genetic relationship of 70 specimens or M. cephalus in Vietnam were divided in three mai...
Phylogenetic relationships among Greek populations of the chub, Leuciscus cephalus, were investig... more Phylogenetic relationships among Greek populations of the chub, Leuciscus cephalus, were investigated using 600 bp of the cytochrome b gene. The aim of this study was to test the assumption that the main difference in ichthyological composition between both sides of the Balkan Peninsula is directly linked to differences in the dispersion mechanisms used by fish in order to extend their distribution range. Phylogenetic and nested clade analyses clearly showed that populations in Greece are significantly differentiated. Greek populations were found to descend from three lineages in three geographical provinces: Western, Central, and Eastern Greece. The chub reached Western Greece at the beginning of the Pleistocene and Eastern Greece during the mid-Pleistocene. Chub dispersion occurred mainly by river confluence due to sea level lowering and river capture in Western Greece and sea dispersal with low-salinity conditions within the Aegean Sea in Eastern Greece. However, in Central Greece, the original mtDNA lineage has presumably been lost owing to a genetic introgression following a second invasion from the Danube during the final stage of the last glaciation. This study provides new elements for a better understanding of the composition of the contemporary ichthyofauna in Greece and highlights possible evolutionary mechanisms responsible for the high endemism rate in the Western Greek biogeographic province. 1999 Academic Press
The taxonomic status of the Bay of Bengal nominal sparid species Coius datnia Hamilton, 1822 and ... more The taxonomic status of the Bay of Bengal nominal sparid species Coius datnia Hamilton, 1822 and Acanthopagrus longispinnis (Valenciennes, 1830) are reviewed and investigated both morphologically and genetically. Because of inadequate description and no type specimen, Coius datnia has recently been considered to belong to Sparidentex, a genus without molarifom teeth. Critical examination of the original description and examination of specimens from the type locality and adjacent areas reveal that Coius datnia belongs to Acanthopagrus, a genus with an inner series of molars. Furthermore, examination of specimens previously recognized as Acanthopagrus longispinnis (Valenciennes 1830), and recent collection of fresh specimens from lower Ganges estuary in Bangladesh, show that morphological differences between Acanthopagrus datnia and A. longispinnis are minor, and they are genetically identical. The longer second anal-fin spine in A. longispinnis (>21% SL) is, in fact, a feature of ...
Mugil cephalus sensu lato is a globally distributed complex of cryptic species whose distribution... more Mugil cephalus sensu lato is a globally distributed complex of cryptic species whose distribution range and evolutionary history remains largely unknown. In the North West (NW) Pacific three species have been identified genetically among fish described morphologically as M. cephalus. Their distribution ranges are largely parapatric and has been proposed to mirror different thermal preferences. To date, few samples have been analyzed from South China Sea, which limits inferences on the evolutionary history of the species complex. We sampled fish identified morphologically as M. cephalus along Vietnamese shores and characterized them using the sequence polymorphism of two mitochondrial genes, the cytochrome oxidase I and cytochrome b. This demonstrated that all three species described in the NW Pacific are present in both northern and southern Vietnamese waters. Although the difference in species abundance reflects those observed in the NW Pacific, no phylogeographic pattern was revealed. In addition, no population structure was observed whatever the species or the distribution range considered, which indicates a significant level of gene flow that maintains genetic homogeneity of the three species. It is also conceivable that each species experienced a recent population expansion from a single ancestral population. Finally we suggest that if the cold waters of the NW Pacific present a physiologic challenge leading to the almost parapatric distribution of the three species, then it is likely that the warm surface temperatures of the South China Sea negate this barrier.
The interrelationships among mugilids (Mugiliformes: Mugilidae) remain highly debated. Using a mi... more The interrelationships among mugilids (Mugiliformes: Mugilidae) remain highly debated. Using a mitochondrial gene-based phylogeny as criterion, a revised classification with 25 genera in the Mugilidae has recently been proposed. However, phylogenetic relationships of major mitochondrial lineages remain unresolved and to gain a general acceptance the classification requires confirmation based on multilocus evidence and diagnostic morphological characters. Here, we construct a species-tree using twelve nuclear and three mitochondrial loci and infer the evolution of 71 morphological characters. Our multilocus phylogeny does not agree with previous morphology-based hypotheses for the relationships within Mugilidae, confirms the revised classification with 25 genera and further resolves their phylogenetic relationships. Using the well-resolved multilocus phylogeny as the criterion, we reclassify Mugilidae genera into three new subfamilies (Myxinae, Rhinomugilinae, and Cheloninae) and one...
Two new species and two new basin records of mahseers in the genera Tor and Neolissochilus are de... more Two new species and two new basin records of mahseers in the genera Tor and Neolissochilus are described from the upper Krong No and middle Đồng Nai drainages of the Langbiang Plateau in southern Vietnam. These new species and new records are known from streams and rivers in montane mixed pine and evergreen forests between 140 and 1112 m. Their populations are isolated in the Sre Pok River of the Mekong basin, the middle of the Đồng Nai basin, and the An Lão River. Both new species are differentiated from their congeners by a combination of the following characters: 23-24 lateral scales, 9-10 predorsal scales, 2/7 or 1/8 pelvic-fin rays, mouth position, median lobe of lower lip, rostral hood, colour in life and by divergent mitochondrial DNA. Tor mekongensis sp. nov. is differentiated from Tor dongnaiensis sp. nov. by the number of transverse scale rows (3/1/2 vs. 4/1/2), number of pelvic-fin rays (2/7 vs. 1/8), a blunt rostral hood vs. pointed, caudal-fin lobes that are equal vs. unequal, and by mitochondrial DNA (0.7% sequence divergence). Molecular evidence identifies both species as members of the genus Tor and distinct from all congeners sampled (uncorrected sequence divergences &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;1.9% for all Tor species for which homologous COI sequences are available). Tor sinensis is recorded in the Krong No and the Sre Pok rivers, further south of its known distribution. Polymorphism is described in Neolissochilus stracheyi with a Tor-like morph and a Neolissochilus-like morph.
Pelagic fish that are distributed circumtropically are characterised by a low population structur... more Pelagic fish that are distributed circumtropically are characterised by a low population structure level as a result of a high capacity for dispersion and large population sizes. Nevertheless, historical and contemporary processes, including past demographic and/or range expansions, secondary contact, dispersal, gene flow, and the achievement of large effective population sizes, may play a part in the detection of divergence signals, especially in the case of tropical pelagic species, whose distribution range depends strongly on the sea surface temperature. The connectivity and historical demography of Atlantic, Indian, Pacific and Mediterranean populations of dolphinfish (Coryphaena hippurus) was studied using partial sequences of the mitochondrial DNA NADH dehydrogenase subunit 1 (ND1). AMOVA analyses revealed significant inter-oceanic divergence with three phylogroups located in the Indo-Pacific, Eastern Atlantic, and Mediterranean Sea, the last one being the most divergent. However, it was not possible to clearly observe any genetic differentiation between the Indo-Pacific and Atlantic populations, as has been reported for most tropical pelagic species of tuna and billfishes. This supports the assumption of recent dispersal among basins facilitated by the actual continuous distribution of dolphinfish populations. Moreover, the lack of a divergence signal for populations separated by the Panamanian Isthmus reveals that genetic drift does not exert a strong influence on tropical pelagic species with large effective population sizes.► Dolphinfish populations around the world harbour a set of widely distributed mtDNA haplotypes. ► The Mediterranean population was isolated by a vicariant event and a demographic crash. ► Dolphinfish have experimented recent dispersal among basins facilitated by range expansions. ► Isolated populations with large Ne, require a significant number of generations to display genetic divergence.
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Papers by Jean-Dominique Durand
The taxonomic status of the keeled back mullets (Teleostei: Mugilidae) has been reinvestigated. Two nominal mugilid species having keeled backs from East Asia: Mugil lauvergnii Eydoux & Souleyet, 1850 and Mugil affinis Günther, 1861 have been re-evaluated through examination of the holotypes and fresh specimens. Comparison of morphomeristic characters of the holotypes shows that both species are identical. Phylogenetic analysis based on mitochondrial cytochrome c oxidase 1 (CO1) confirmed morphological data by highlighting presence of a single clade from East Asia. Mugil lauvergnii (=Planiliza lauvergnii) is thus the sole keeled back mullet from East Asia and a senior synonym of Mugil affinis (=Planiliza affinis). The taxonomic status of two other keeled back mullets, Planiliza carinata and P. klunzingeri, is also contentious due to their similar morphology. Meristic and morphometric variation as well as sequence divergence between the two species are limited but phylogenetic analyses delineate well-supported clades consistent with
biogeography and currently accepted taxonomy. Planiliza carinata and P. klunzingeri share a recent common ancestor in a Maximum Likelihood tree, with separate distribution ranges while P. lauvergnii formed a paraphyletic lineage. Based on present findings, we suggest maintenance of the taxonomic distinction of P. klunzingeri and P. carinata and discuss its evolutionary significance.
The taxonomic status of the keeled back mullets (Teleostei: Mugilidae) has been reinvestigated. Two nominal mugilid species having keeled backs from East Asia: Mugil lauvergnii Eydoux & Souleyet, 1850 and Mugil affinis Günther, 1861 have been re-evaluated through examination of the holotypes and fresh specimens. Comparison of morphomeristic characters of the holotypes shows that both species are identical. Phylogenetic analysis based on mitochondrial cytochrome c oxidase 1 (CO1) confirmed morphological data by highlighting presence of a single clade from East Asia. Mugil lauvergnii (=Planiliza lauvergnii) is thus the sole keeled back mullet from East Asia and a senior synonym of Mugil affinis (=Planiliza affinis). The taxonomic status of two other keeled back mullets, Planiliza carinata and P. klunzingeri, is also contentious due to their similar morphology. Meristic and morphometric variation as well as sequence divergence between the two species are limited but phylogenetic analyses delineate well-supported clades consistent with
biogeography and currently accepted taxonomy. Planiliza carinata and P. klunzingeri share a recent common ancestor in a Maximum Likelihood tree, with separate distribution ranges while P. lauvergnii formed a paraphyletic lineage. Based on present findings, we suggest maintenance of the taxonomic distinction of P. klunzingeri and P. carinata and discuss its evolutionary significance.